ISSUE 28

May 2023 transformer-technology.com ISSN 2642-2689

ADVANCED
TRANSFORMER
TESTING AND
TECHNOLOGIES
POWER SYSTEMS TECHNOLOGY

Solid State Technology to Streamline Global Transition to Clean Energy

Root Causes of Partial Discharge
Interview with Seth Johnson, Vice President, Powerside
Better
transformers
by design.
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fluid, trusted in over 3 million transformers worldwide -
choose FR3® fluid by Cargill for higher-performing, safer,
more sustainable, and cost-effective ways to power how your
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Higher load capacity
20% more load capacity compared to
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More reliable
10x higher moisture saturation point
compared to mineral oil.

Fire safety
2x higher flash point compared to
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Better for the planet

Global Warming Potential of zero and
carbon neutral.

© 2023 Cargill, Incorporated. All rights reserved. FR3FLU ID.CO M

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transformer-technology.com
4 TABLE OF
CONTENTS

Contents 12
Interview with

Table of
Javiera
McGuiggan
Global Business
Director for Power
Systems, Cargill

Index Powering the

Local Economy
with Sustainable
Table of Contents_04
Solutions

Editors & Impressum_08

Letter of the Editor_10
Interview with Javiera McGuiggan,
Global Business Director for Power
Systems, Cargill_12
Root Causes of Partial Discharge_20
Interview with Ben Lanz, Director of
Strategy and Development, IMCORP,
Executive Board member, PDi2_28
New technologies can help
compensate for the loss of
personnel knowledge and the
increased demands on
operating equipment – Part 2_36
Interview with Ulrich Voss,
Vice President, Marketing
and Sales for Power
Transformers, SGB-SMIT;
Marcel Hilgers, Head of Sales,
Technical Customer Service,
and Communications,
thyssenkrupp; and Hossain
El Hachhouchi, Manager of
Procurement, Enexis_42
20
Root Causes of
Partial Discharge
Transformer Technology May 2023 5

Issue 28

28
Interview with
Ben Lanz
Director of Strategy and
Development, IMCORP, Executive
Board member, PDi2

Overcoming Natural
Challenges with Benefits
of Undergrounding

42
Interview with
36 Marcel Hilgers
Head of Sales, Technical Customer
Service, and Communications,
New technologies can thyssenkrupp
help compensate for
Hossain El Hachhouchi
the loss of personnel Manager of Procurement, Enexis
knowledge and the
and
increased demands on
operating equipment
Ulrich Voss
Vice President, Marketing and
PART 2 Sales for Power Transformers,
SGB-SMIT

Green Steel for

Sustainable Transformers
6 TABLE OF
CONTENTS

Contents

Table of
Index
Field Testing of Current
Transformers: Challenges and
Mitigation Techniques_50
Interview with Prabhat Jain,
CEO-CTO of Virginia Transformer
Corp_60
Looking Backward to See a Way
Forward_66
Interview with Seth Johnson, Vice
President, Powerside_72
50
Solid State Technology to
Field Testing of
Streamline Global Transition to
Current Transformers:
Challenges and
Clean Energy_80
Mitigation Techniques
Interview with Claudia Cosoreanu,
Chief Technology Officer for Grid
Automation, GE, and Claudia

60
Blanco, Innovation and Customer
Partnerships Officer, GE_86
Interview with Chip Angus,
Interview with
Reliability Account Manager, Prabhat Jain
CEO-CTO of Virginia
SDMeyers_92
Transformer Corp
Coming in June_99
Conquering the
Transformer
Shortage
Transformer Technology May 2023 7

Issue 28

66
Looking
Backward to
See a Way
Forward
72 86
Interview with
Interview with Claudia Cosoreanu
Seth Johnson Chief Technology Officer for Grid
Automation, GE
Vice President,
Powerside and
Claudia Blanco
Challenges of Innovation and Customer Partnerships
the Grid Today Officer, GE

Cooperation for the Power

Systems of the Future

92
Interview with
Chip Angus
80 Reliability Account Manager, SDMeyers

Solid State Technology Transformer Testing –

to Streamline Global a Pathway to Better Resiliency
Transition to Clean Energy
8 EDITORS &
IMPRESSUM

Impressum TAB Executive Advisor,

The Chair and Managing Editor
Alan M. Ross, CRL, CMRP
Transformer maintenance and
reliability

Technical Advisory Board (TAB)

Executive Advisors TAB Executive Advisor
Alan M. Ross, CRL, CMRP Corné Dames
The Chair and Managing Editor Independent transformer
Corné Dames consultant Transformer oils
Independent transformer consultant
Transfomer oils
Ben Lanz, IEEE PES Senior Member
Power system reliability, asset management
and diagnostics TAB Executive Advisor
Technical Advisory Board Members Ben Lanz, IEEE PES Senior Member
Diego Robalino, PhD, PMP Power system reliability,
IEEE Senior Member asset management
Tony McGrail and diagnostics
Asset management & Condition monitoring
Edward Casserly, PhD
Senior Scientist, Transformer oils TAB Member
Maria Lamorey
Diego Robalino PhD, PMP
Industrial OEM manufacturing
IEEE Senior Member
Alan Sbravati, ME, MBA
Transformer insulating materials Transformer condition
Marco Tozzi, PhD assessment and
Diagnostics and asset monitoring diagnostics
Curtus Duff
Power transformer design
Traci Hopkins, IEEE Member
Transformer Condition Assessment
Jon Trout, PE
TAB Member
Electric utility
Michael Riccio, CRL, IRT CAT-1
Tony McGrail, PhD
Reliability, Electrical safety Asset management &
Alexander Doutrelepont Condition monitoring
High voltage bushings & insulators
Ed Khan
Power Systems, Relay protection, Training
Graphic design
BE Koncept Communication Boutique TAB Member
Photo Cover Edward Casserly, PhD
Shutterstock Senior Scientist,
Transformer oils
Sales & Marketing
Rachel Linke
rachel.linke@apc.media
Kevan Sears
kevan.sears@apc.media
Sales & Marketing Americas TAB Member
Jose Mora Maria Lamorey
Jose.mora@apc.media Industrial OEM
Sales & Marketing Mexico manufacturing
Fernando Campos
fernando.campos@transformer-technology.com

Sales & Marketing Brazil

Marcelo Braga
marcelo.braga@transformer-technology.com TAB Member
Marketing Global Alan Sbravati, ME, MBA
Marin Dugandzic Transformer insulating
marin.dugandzic@apc.media materials
Transformer Technology May 2023 9

Issue 28

Editors
TAB Member
Marco Tozzi, PhD
Diagnostics and asset
monitoring

ISSN 2642-2689 (Print)

ISSN 2642-2697 (Online)
TAB Member
DIGITAL Membership Curtus Duff
Free Power transformer design
Transformer Technology magazine is a quarterly
magazine published by APC MEDIA LLC, 2152
Caper Dr., Marietta, GA 30064, USA. Published
content does not represent official position of APC
MEDIA LLC. Responsibility for the content rests TAB Member
upon the authors of the articles and advertisers, Traci Hopkins
and not on APC MEDIA LLC. APC MEDIA LLC Transformer Condition
maintains the right to keep the textual and Assessment
graphical documents submitted for publication.
Copyright and reprint permission
Abstracting is permitted with credit to the source.
Libraries are permitted to photocopy isolated
pages for private use of their patrons. TAB Member
For other copying, reprint or republication Jon Trout, PE
permission requests should be addressed to Electric utility
info@transformer-technology.com
Publisher:
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2152 Caper Dr.
Marietta, GA 30064, USA
transformer-technology.com TAB Member
Michael Riccio, CRL, IRT CAT-1
Reliability, Electrical safety

TAB Member
Alexander Doutrelepont
High voltage bushings
& insulators

TAB Member
Ed Khan
Power Systems,
Relay protection, Training
10 LETTER FROM
THE EDITOR

Dear Readers,

We are all aware that power transformers are and lightweight than conventional transformers,
critical components that play a vital role in power while still providing high levels of reliability and
delivery systems. They are used to step up or performance. Gas-insulated transformers are be
step-down voltage, depending on the needs of
the power system. They are also used to isolate coming increasingly popular in urban areas, where
circuits, provide galvanic isolation, and protect space is at a premium. They are also being used in
against surges and over-voltage conditions. Over high-voltage direct current (HVDC) transmission
the years, there have been significant advances systems, where they can provide high levels of
in transformer technology, driven by the need for insulation and reduce power losses. Even now
more efficient, reliable, and cost-effective power there is work underway to replace SF6 gas in all
delivery systems. Just a few of these advances are: applications with new gases that have similar

Over the years, there have

been significant advances in
transformer technology, driven
by the need for more efficient,
reliable, and cost-effective power
delivery systems. Here we are
naming a few of these advances.

Growth of Inverter Transformers properties but without the negative aspects of SF6.
Inverter transformers are used in high-power An interview I conducted with Marcus Heimbach
electronic circuits. They are designed to operate at of Hitachi Energy is an excellent discussion of
high frequencies and can handle very high voltages this issue.
and currents. Inverter transformers are becoming
increasingly popular in power conversion systems, Smart Transformers
such as solar power systems, wind power systems, Smart transformers incorporate advanced moni-
and hybrid electric vehicles. The development toring and control systems. They are designed to
of inverter transformers has been driven by the provide real-time monitoring of power quality,
need for more efficient and cost-effective power load conditions, and other important parameters.
conversion systems. Smart transformers can also be used to provide
real-time control of power flow, voltage levels, and
High-temperature Superconducting other key variables. Smart transformers are being
Transformers (HTS) developed for use in distributed energy systems,
HTS transformers are transformers that use su- such as microgrids and renewable energy systems.
perconducting materials to transmit electrical They are also being used in data centers, where
power. They are designed to operate at very low they can help to improve power efficiency and
temperatures, typically below -180°C. HTS trans- reliability.
formers are highly efficient and can handle very
high-power densities. They are also very compact Solid-state Transformers
and lightweight compared to conventional trans- Solid-state transformers are transformers that use
former designs. HTS transformers are being power electronics to convert power from one
developed for use in power transmission and voltage level to another. They are designed to be
distribution systems, as well as in high-power mag- more efficient and cost-effective than conventional
nets for medical imaging and particle accelerators. transformer designs. Solid-state transformers are
being developed for use in renewable energy
Gas-insulated Transformers systems, as well as in electric vehicle charging
Gas-insulated transformers are transformers that systems. They are also being used in power trans-
use sulfur hexafluoride (SF6) gas as an insulating mission and distribution systems, where they can
medium. They are designed to be more compact provide improved grid stability and reliability.
Transformer Technology May 2023 11

Issue 28

Alan M Ross
Conclusion:
In conclusion, advances in power transformer
technology have led to significant improvements
in power delivery systems. With the development
of inverter transformers, high-temperature super-
conducting transformers, gas-insulated trans-
formers, smart transformers, and solid-state
transformers, power systems can now operate
more efficiently, reliably, and cost-effectively
than ever before. These advances have been
driven by the need for more sustainable energy
systems, as well as the need for better grid
stability and reliability. As technology continues
to evolve, we can expect to see even more exciting
developments in power transformer technology.
Managing Editor
Alan M Ross

Technical Director
CRL, CMRP

APC Media
12 FEATURE
INTERVIEW

Javiera McGuiggan
 Transformer Technology May 2023 13

Issue 28

Global Business Director for Power Systems

If we do our job
right and people

at Cargill BioIndustrial
realize how good
biobased solutions
are for them,
there'll be many
others that come
Interview with Javiera F. McGuiggan
later and want to
participate in the
biodegradable
biobased products
market.
Photo: Javiera F. McGuiggan
14 FEATURE
INTERVIEW

Alan Ross: My next guest is Javiera McGuiggan. are interested in having a rapeseed version,
She is the Global Business Director for Power and other customers in this market are using
Systems at Cargill. Thank you so much for rapeseed, we don't want people to think they
joining me. cannot get that solution from Cargill, because
now they can.
There's something new on the market –
rapeseed oil. What is the rapeseed oil thing
that you're doing with FR3? AR
that.
That's excellent. I love the idea of a
localized crop; everybody would want

Javiera McGuiggan: This week, middle of

February, we are launching FR3r, which is like
FR3's little cousin made out of rapeseed oil.
Rapeseed is exactly the same as canola.
JM Helping your own economy, avoiding
moving things around too much,
saving on transportation and reducing
contamination – if we can do things locally, we

AR My next question is, why have

another product when we know FR3
works? And it works really well.
will try to do that too. That's why we have so
many plants everywhere. This will be produced
at a new European plant.

JM It works fantastic. What is mostly

driving this need is that it is pushed
by the European market. They have this crop
AR Cargill has played a major role in
decarbonization because you are
using plant-based oils as opposed to mineral
available, so they like the localized oil. That's oils. I heard recently an argument that refining
one of the drivers. It's sort of already embedded mineral oil now is a green. It's still mineral oil, a
in some people's head that soy could be carbon-based product. Why would they try to
damaging the environment. It doesn’t, but we equate mineral oil that's been repurposed to a
want to make it clear for people that this is not plant?
a better product, it's just different crops. Being
such a big agent in agriculture, we can make
the product out of anything. We know that soy
is the best combination of performance and
JM Sustainability is a super important
topic. There's no company that doesn't
want to achieve that and contribute in some
cost that is available right now. But if people way. We can argue about life cycle analysis and

We know that soy is the best combination

of performance and cost that is available right

now. But if people are interested in having

a rapeseed version, and other customers in

this market are using rapeseed, we don't want

people to think they cannot get that solution

from Cargill, because now they can.

 Transformer Technology May 2023 15

Issue 28

numbers and spreadsheets, but can you find I applaud the effort of anyone that makes
anything that would be greener or better for the something that contaminates the world and
world than a plant? No. tries to reuse it for another purpose before it's
thrown away. We can also do that with FR3, and
For an LCA analysis, life cycle analysis, where that's not the point. The point is, I don't want
you're measuring the amount of carbon that's anyone to get confused to the level of thinking
emitted to the world, mineral oil as a petroleum- that mineral oils are better than FR3, because
based solution contributes a lot to CO2 emissions, we're comparing them to a plant, so there can't
which then leads to global warming. We want to be anything greener. That's the end of the
avoid that, not only to the level of neutral, but discussion.
hopefully to the level of negative. When you start
from a plant, as the plants are alive, they have a
biogenic property where they are absorbing CO2,
so they're literally doing the opposite effect. Some
AR You're the global head of Power
Systems at Cargill, so you see the
world from a different point of view. The
LCAs take in effect, the farming and the whole world is not the same in adopting all of these
agriculture, and they ignore the fact that the things. Who's ahead, who's behind, who is really
plant was sitting there, breathing and absorbing supporting biodegradables, and who is just
CO2. Then you consider all the normal farming nascently getting into it?
processes, then the production of FR3, and you get
to a number that's much better than mineral oil,
because, again, it's a plant. Even negative, if you
add the biogenic composition of the plant.
JM The ones that are the most ahead
are linked to the most developed
economies. The United States is the largest
consumer of biodegradable biobased products.
Petroleum solutions are claiming that they can Then there's a very accelerated push in Europe.
reuse that product for something else, which, I feel Europe needed a little more of the proof
don't get me wrong, is fantastic. It's what the that it works and how it's going to affect their
world needs, less waste. Reusing mineral oil – pockets and if they can financially establish
great. Can you reuse FR3 for other things? Also it. But they have aging grids, and a bunch
true. It doesn't take away from the fact of all of other benefits that they get from these
the carbon that was emitted at the beginning to biobased solutions, so they are in a very much
produce mineral oil. accelerated pace compared to what they have
Photo: Cargill
16 FEATURE
INTERVIEW

been before. And then also Latin America has which is the best natural ester. I can raise my
been very much convinced that this is the right hand – I think I have the best one for sure. But at
solution. In countries like Brazil almost 90% least I'm not still trying to convince people that
of their distribution grid is now all in natural it works, or to trust it. It's more of a wave of “we
esters. Those are the three areas that I would say know it works”. There's just more activity in the
are driving the change. Next to that, there are market, and I think overall, for the planet, it's a
countries that are making really great efforts. good thing.
South Africa turned all their grid into natural
esters. The Philippines also established that.

Slowly but surely, all the rest are catching up. In

AR I was the president of the Electric
Power Reliability Alliance, we had a
lot of labs that we worked with, and they were
Asia, Japan, Korea, China are dipping their toes doing a lot of testing of FR3. As they began
into the water, but they'll catch up pretty quickly. to build up the data, they began to see some
Once they get into it, they'll go super fast. benefits to FR3 that weren't there in mineral oil.
Speak a little bit about those. Sell me on FR3.
I’ve always said, if we do our job right and
people realize how good this is for them, there'll
be many others that come later and want to
participate in this market. And that, to me, is in
JM If it's something related to lab analysis,
one of the easiest things you could
find is how FR3, just for the pure nature of the
general a good thing – having more competition science of how vegetable oils work, deals with
– because at least we're all trying to defend moisture and free water. The molecules of
 Transformer Technology May 2023 17

Issue 28

soybean oil absorb the water into two separate like it. But he hated it because he would see no
components, so then it's not free water that can change in the oil. It's good with heat, robust.
then get attached to your solid insulation. And
that's how FR3 extends the life of a transformer.
There is a chemical reaction with water that
stops it from attaching to the solid insulation.
AR I learned just recently that FR3 can
withstand overheating significantly
better than mineral oil. When you think about
where we are right now, the demand on the
It's hard to explain, but FR3 is good at aging. grid is growing. Everybody is having to produce
It doesn't go brown; it doesn't get burned. more. You can't get more transformers. They're
You open a transformer with FR3 that's been three years out in some cases. And we've had a
working for 15, 20 years, and it almost looks couple of transformer manufacturers here share
exactly the same with us the difficulty they're trying to ramp up.
You've got to keep the existing infrastructure
At a utility in California, I met an engineer, and working. Therefore, you're going to overheat and
he says: “I don't like your fluid, because if I open overload your transformers.
a mineral oil transformer, I look at the oil, I know
exactly what's happened to this transformer. What is the cost of retrofilling in comparison to
I know what it's been through. I know how long the value of retrofilling with FR3? We know the
it's been working. I know what could be failing. safety issues, the fire retardancy. We know that
Photo: Cargill

I open one of yours, and I can't tell anything.” if you're near water, you don't want mineral oil
And I'm like, exactly. That's why you usually to spill in water.
18 FEATURE
INTERVIEW

JM How much value you get versus what

the cost of it is a really great question,
because when you think of a new transformer,
engineers working at our plants for all the
capacity increases that that we need at our
plants. We are, thankfully, good at retaining.
the initial ratio of the price of the oil versus It's a lesson for all of us to learn – treat your
the total cost of a transformer is anywhere employees well and retain them, because it's not
between 5% to 8% of the cost of the whole unit. as easy as it used to be to just get new talent all
So maybe initially when you're buying the of a sudden.
whole unit and you have a fluid that's a bit more
expensive than your incumbent mineral oil, you
just elevate the cost of the whole unit. And you
think, do I want to spend that money when I'm
AR We did surveys as part of a group
I'm part of, and what used to be
the number one reason that people look for
already having to buy all these transformers? something new in their career was pay, benefits,
After a while, mineral oil transformers either job security. Now it is wanting to make a
need a refresh, or retrofilling, or adding a couple difference.
of additives that have maybe worn out. In the
case of FR3, that won't happen. When you just
evaluate the cost of oil versus oil, it's such an
insignificant cost compared to the labor of even
JM This generation wants to feel their
job means something. And also, after
COVID, they want the freedom that to me is a
doing this maintenance. little scary – people don't even want to go to a
work environment, to an office, or to a plant.
Another engineer in a utility in California said: They just want to work from home. I understand
“I want to just put this oil in there because then it, and I value the balance of a hybrid situation,
I know I don't have to touch it again.” Labor cost but I think the interaction between people,
for the maintenance of a transformer could be the collaboration in person, and especially for
four times more, depending on the location of newer engineering graduates, the need to gain
the transformer. You have the crew that has to that experience from the people that have
go there, the time spent on shutting it down, been there before, is important. There's got
getting it off the grid, doing this maintenance. to be an adjustment coming, hopefully soon,
Then on top of that, if you already have the of people realizing that a hybrid system and
transformer working and you can extend the a working from home situation are great, but
life, then again, you have to buy units less we also have to embrace real life, transferring
frequently, which is another economic factor knowledge, transferring information, and just
that is not easy for some people to integrate daily collaboration.
into their equations. They're just thinking
about the initial cost, but it's much, much less
significant as a maintenance operation to then
do this retrofill compared to all the benefits
AR Another thing is what people want
out of a career is community. They
want to know they're part of something that
that you would get out of it, because you get does something for society, but they also want
90% of all the same benefits that you get from a to know they're part of a community.
new Transformer with FR3.

People always ask, if there's a little mineral oil left

in there, would it still work? And yes, it does.
JM And you cannot be a part of a
community when you're sitting just on
the video screen. Especially when people don't
turn it on so many times. It's understandable,

AR Last question. Labor is an issue

now, right? You are on the steering
committee of Women in Power Systems. Getting
but it's sad because then you don't get any
connection if you don't even turn on your
camera.
more women engineers into STEM, science,
technology – you're a real champion for that, Sometimes it's hard, especially for women, to
and Cargill is a real champion of that. But now find a work life balance. You have your kids at
there's just a huge problem of getting any staff. home or you're doing something, and women
Yet, are you suffering from that same thing, is have to get all pretty to be on camera. There is
Cargill as a whole suffering from it? Or how do a lot more social pressure to look okay in front
you help industry address it? of a camera. I understand it, but when possible,
at least that minimum interaction of the video

JM We even struggle with filling some

positions in our team that are in a
being on is very valuable.

great company and exciting. But finding the

right mix of the right energy to sell something
that is changing the way people used to think
AR That's true. It has been a delight, as
always.

about something is not just sales. It's telling a

story. It is getting harder and harder to find JM Thank you so much.
 Transformer Technology May 2023 19

Issue 28

The molecules of soybean oil absorb the

water into two separate components, so then

it's not free water that can then get attached

to your solid insulation. And that's how FR3

extends the life of a transformer.

Photo: Cargill
20 PARTIAL
DISCHARGE

Root Causes
of Partial Discharge
by Corné Dames

Introduction these gas pockets might occur due to

thermal deterioration, stator winding
Power transformers are some of the movement during operation, or due to
most expensive components of any other reasons. As the deterioration of
power generation system. Reliable the insulation increases, the number
operation of all the components and magnitude of the PD will increase.
within the system is crucial to ensure The breakdown of the gas inside the
sustained power delivery. This voids creates small voltage pulses
reliability strongly depends on the that can be detected and measured,
ability of the insulation system to and therefore it is possible to monitor
withstand the impact of the continued the PD. Although the magnitude of the
electrical and mechanical stresses PD pulses cannot be directly related
on the system during its lifetime. to the remaining life of the winding
During this service time, all the insulation, the rapid increase in the PD
items forming part of the electrical activity or other indicators of insulation
system undergo deterioration to their deterioration would be a clear indication
insulation systems, this might be due that the reliability of the equipment is
to various contributing factors like compromised. The testing to determine
electrical, mechanical, thermal, and the presence of partial discharge is a
chemical stresses. Due to this normal proactive diagnostic measure to ensure
deterioration process taking place, the reliability of electrical equipment.
some “weak” areas with a decreased
capability to withstand dielectric Partial discharge is defined as an
stresses are potential sources of electrical discharge that does not
permanent partial discharge (PD) completely bridge the space between
activity. PD measurement is one of two conducting electrodes. Partial
the non-destructive methods available discharge can occur in various
which can detect local defects in locations in medium and high-voltage
complex electrical insulation systems. equipment. We can differentiate
between roughly four types of partial
What is Partial Discharge? discharge. Each of these types of
partial discharge can occur due to
For more than half a century, it different reasons and each with the
has been a known fact that partial ability to cause varying levels of
discharge is a symptom of several damage to the system. A minor defect
problems caused by thermal, or deterioration of the insulation
mechanical (vibration and shock), encapsulating the conductor might
electrical (voltage), environmental, be the cause for the phenomenon of
and chemical processes. partial discharge taking place. Partial
discharge presents as a repetitive
Partial discharges are small electrical sequence of discharges propagating
sparks that occur within the electrical within the insulation and growing
insulation of switchgear, cables, over time. Once the insulation is
transformers, and the windings in broken down sufficiently to form an
large motors and generators. Partial unrestricted path for the charge to
discharge is the small electrical flow from one conductor to the other,
sparks that occur when gas pockets it will result in an arc flash that might
exist within the high voltage insulation, be fatal to the equipment.
 May 2023 21

Corné Dames is the Managing Director of

Independent Transformer Consultants, al-
ways striving to keep on top of new devel-
opments and research. She has expertise

Once the insulation as Laboratory Manager in the analysis of

transformer oils and as diagnostician iden-
is broken down tifying problem areas in transformers, as
well as profiling of transformers accord-
sufficiently to form ing to available results thus empowering

an unrestricted path the customer to take preventative steps in

maintenance. Corné has vast practical and
for the charge to flow theoretical knowledge on reliability main-

from one conductor tenance programs. Coming from a strong

chemical background she has insight in
to the other, it will all the chemical processes that are part
of the transformer system. Coupled with
result in an arc flash technical insight, her knowledge and ex-

that might be fatal to perience help customers optimize their re-

liability maintenance and electrical asset
the equipment. lifetime.
Photo: Shutterstock
22 PARTIAL
DISCHARGE

There might be various causes for 2. PD of the sparking type

partial discharge. The discharge This will occur in liquid (oil) or
always starts as a small insignificant solid (paper) insulation. These
scenario that might escalate to are small arcs and therefore their
ultimate failure at the end of the day. temperatures are very high (more
Another definition for partial discharge than 3000° C). They produce
might be the inability of a portion mostly C2H2 (Acetylene) and H2
of the insulation to withstand the (Hydrogen) and this will damage
electrical field applied to it, or more the paper insulation (carbonized
formally, a flashover of part of the pinholes, tracking) and the oil
insulation system due to a localized will be decomposed, therefore
electric field greater than the dielectric dissolved gases would be present
withstand capability of a part where in the oil).
the overall insulation system remains
capable of withstanding the applied Defects possibly generating
electrical field. [1] Partial Discharge in
transformers. [3]
Types of Partial Discharge
In a transformer with a good
We generally differentiate between two design and manufactured to
types of partial discharge: the highest standard, it is very
unlikely for PD to initiate during the
1. PD of the corona type early life of the transformer unit.
In a transformer this type of However, some discharges might
partial discharge will present as be present as noticed during oil
gas bubbles in the oil where the sampling and PD measurement
gas is ionized in cold plasma of done during commissioning. For
low (ambient) temperature, it will these discharges to initiate the has
mostly produce Hydrogen gas to be some defects present in the
(H2) together with some Methane insulation system.
(CH4) and will not cause damage
or carbonization of the paper a) Delamination may occur when
insulation. PD of the corona type is the thinner pressboard sheets
also used to describe discharges are glued together to form thicker
into air or gas at the terminals barriers. Voids within these
of the transformer under test. If delaminations might remain for a
shielding electrodes are not used. long time.

Equipotential Lines [1]

Photo: Shutterstock 23
24 PARTIAL
DISCHARGE

b) Voids – Voids may occur in glue Fibers sticking out from the In a transformer
and Connections with enameled cellulose surface or fibers moving
thread, insufficient impregnation in the oil might initiate discharges. with a good design
of the paper with oil might Increased moisture content will and manufactured
cause voids to form. It might be also increase dielectric losses.
possible that these types of voids During a cooling cycle, moisture to the highest
disappear from one day to the
next as the gases are absorbed by
might be absorbed locally by the
pressboard. As a result, internal
standard, it is very
the oil and the cavity is filled with discharges may become prevalent unlikely for PD
oil! Voids might also be present in in the cavities within the press
bushings, a high moisture content board. to initiate during
in combination with heat and f) A bad connection of electrostatic the early life of
mechanical and electrical fields shields will give large discharges
may create a high local water because the capacitance of the transformer
vapor pressure with a resulting
"puffing" effect of boards and
the defect is large. The "bad"
connection will usually have a
unit. However,
winding insulation. Discharges in defined breakdown voltage (Ubd). some discharges
the "spongy" material may start The result is the disappearance
shortly after this occurrence. of charges on the rising flank with might be present
c) Bubbles formation might be due voltage-independent amplitudes. as noticed during
to gas formation because of the g) Static electrification – This will
discharges as well as evaporation give rise to the deposition of local oil sampling and
of water droplets. It has been
shown by field studies that a gas
charges. The enhancement of
the resulting field may initiate
PD measurement
bubble in an open oil volume will discharges. The discharge tracks done during
be ripped into smaller bubbles, due to these types of discharges
which will disappear quickly. have been noticed along commissioning.
Bubbles will therefore only exist pressboard surfaces during visual
in locations Where they are inspection.
supported by solid insulation. h) Surface tracking – This is a result
d) Free metallic particles- possibly in of discharge propagation and has
the wood or stuck to the paper in been found along barrier surfaces
the windings. and supports. Carbonized tracks
e) Moisture – This will occur due can act as conductive protrusions,
to the aging of the insulation and may over time increase in
or might be introduced into the length.
system during commissioning
or maintenance work on the Measurements of PD on
transformer. Moisture will transformers
contribute in various ways
to discharge inception and 1. Off-line testing in the laboratory
extinction. During a heating cycle This is used for quality assurance
when the transformer is in service and acceptance testing (Factory
(after re-energizing a transformer Acceptance Testing – FAT) The application of new diagnostic
that has been offline), moisture to reveal contamination, methods might be due to
might be pressed out of the manufacturing deficiencies, 1. The movement from a time
solid insulation. Due to the poor or incorrect design. to a condition-based
solubility of water in the oil, there maintenance strategy
might arise a supersaturation 2. On-site PD diagnostic 2. The early recognition of
of the oil next to the cellulose measurement insulation degradation
surface with moisture. This might This could be done online or 3. Detection of incipient faults
result in water droplet and bubble offline for Site Acceptance Testing. 4. Reduction of the cost of outages
formation (2). On-line monitoring for new or and unplanned apparatus
Evaporation of the water will aged transformers, as a condition repairs or replacement.
cause the formation of micro- assessment tool. This is an 5. Staff safety
bubbles and this will lead to on-site test for new or service- 6. The reduction of risk to the
discharges. An increase in the aged equipment. This is mainly environment
moisture content in cellulose used for the commissioning of 7. To identify bad workmanship
paper will make the paper new equipment or after repairs after final assembly
more conducive. Under these have been done, or for diagnostic 8. Fleet characterization
conditions, the cellulose fibers will purposes as part of the asset 9. Optimization of investment
start acting like metallic particles. management program. decisions
 Transformer Technology May 2023 25

Issue 28
Photo: Shutterstock
26 PARTIAL
DISCHARGE

In the past, on-site in-service PD Difference between online and On-site it is most important to
source detection involved dissolved off-line PD measurements ensure the accurate and repeatable
gas analysis based on the taking of determination of the partial discharge,
oil samples from the transformer Advantages of On-line PD to monitor the deterioration as well as
tank, using Hydrogen as the key measurements the rate of the deterioration. For this
indicator for PD activity in the active 1. Online PD measurements can be reason, it is crucial to use the same
part of a transformer. DGA as an performed while the generator is equipment for consecutive tests on
indirect measurement is slower to running. They can be performed a specific unit as different test sets
identify a rapidly evolving PD and at any time, while off-line PD might lead to a deviation in results.
is usually unable to localize the PD measurements can only be
for additional risk assessment. DGA performed when the generator is The most important test is the
interpretation requires a minimum removed from service. This makes initial partial discharge test after
amount of gas formation to declare online measurements much more commissioning to establish a baseline
a PD activity as significant [Duval cost-effective. parameter, or fingerprint, to build on
2001]. There are also several practical Online measurements also provide and for future reference. Also, the initial
examples where no increase of the possibility to monitor the PD PD reading is extremely important
combustible gases was recorded activity of the generator. to ensure that no damage has taken
despite a PD source being detected 2. The operating conditions of the place during the transport of the unit
by electric and acoustic methods generator influence its PD behavior. and the commissioning steps.
and confirmed through visual Taking the generator off-line
inspection of the transformer. It can Reference data is crucial to ensure
be stated that electric, acoustic, and Advantages of off-line PD testing reliability.
electromagnetic PD pulse-based 1. It is possible to measure the
measurements are more reliable
in determining PD activity. These
PD activity at different voltage
levels. This enables the operator
It is important to
methods can be used for the in- to determine the inception and notice that the on-
depth analysis of PD activity and the extinction voltage of PD activity
assessment of the severity of the and thereby helping him in the site testing of partial
threat of PD to the safe operation of assessment of the stator insulation discharge is a delicate
the transformer. condition.
2. Generally, off-line PD measure- science and the
In the electrical system, we have the
following measurable physical signs
ments have a higher signal-to-
noise ratio and the influence of
practical facts are that
that occur as a result of PD. disturbance signals is lower. This we are faced with a
will result in higher sensitivity,
● Electrical signals are measurable at selectivity, and resolution for the lot of “noise” – partial
the bushings of the transformer offline PD measurements. discharge in the
● Electro-magnetic transient waves
(up to GHz range) are measurable Conclusion background, generated
via antennas
● Acoustic sound waves are From this information, it is clear that
by other equipment in
measurable via acoustic sensors we only touched the tip of the iceberg. proximity of the test
on the tank of the transformer So much is left to be said about the
● The decomposition of the test methods and interpretation of object.
insulating material ( oil and partial discharge data which should be
cellulose) is detectable by analysis addressed in a follow-up article. References
of an oil sample. [1] IEEE Alberta Partial
It is important to notice that the on-site Discharge by Tim Erwin of EA
Electric, testing of partial discharge is a delicate Technologies
science and the practical facts are [2] V.G. Davydov, O.M. Roizman,
acoustic, and that we are faced with a lot of “noise” W.J. Bonwick, " Transformer

electromagnetic – partial discharge in the background,

generated by other equipment in
insulation behavior during
overload."EPRI Substation
PD pulse-based proximity of the test object. The Equipment Diagnostic
filtering of the signal when determining
measurements the partial discharge of the test object
Conference. V,TR 111282,1989,
pp II -53 to II -72
are more is the biggest challenge. [3] Cigre Brochure 226, Task
Force 15.11/33.03.02 – April
reliable in Many companies have equipment 2003, “Knowledge rules for

determining PD with the capability to filter out

the background partial discharge
Partial Discharge Diagnosis in
Service.”
activity. originating from outside sources.
 Transformer Technology May 2023 27

Issue 28
Photo: Shutterstock
28 FEATURE
INTERVIEW

Ben Lanz
 Transformer Technology May 2023 29

Issue 28

Director of Strategy and Development at IMCORP

Undergrounding has

Executive Board member at PDi 2

a societal benefit, a
long term benefit.
Investment decisions
should evaluate the
"total cost of ownership"
of overhead versus
underground over
the life of the asset.
Interview with Ben Lanz

This is how we will

get maximum societal
benefit.
Photo: Ben Lanz
30 FEATURE
INTERVIEW

Alan Ross: My next guest is a friend and a first realize. We're promoting sound decision
brother, and this is going to be fun. Ben Lanz is making based on the lifecycle cost and giving
the Director of Strategy and Development at people case studies they can use to pattern how
IMCORP. He is also an early Executive Board leading utilities make investment decisions and
member of PDi2. Ben, thank you for being here. what parameters to include in the models that
they're using to justify costs.
We're going to go on two tracks. One of them
is to talk about when you formed PDi2, who We're promoting sound decision making based
formed it and why it was formed, and what you on the lifecycle cost and giving people case
think is going to happen. studies they can use to pattern how leading
utilities make investment decisions and what
Ben Lanz: While I was very involved in building parameters to include in the models
the organization to where it is today, the original that they're using to justify costs.
group was a smaller subset. It included Dow
and Borealis as material suppliers, some wire
and cable manufacturers, and companies like
Quanta, who install overhead and underground
AR I have a son, a daughter-in-law and
a grandbaby in California. My wife
and I spend a good bit of time there. One of the
power systems. We noticed that when we visit big things in California that we deal with are
with utilities and industrials alike, there's a all of the weather-related things and fires. But
lot of myths and rules of thumb that people I understand there's a hunger within California
follow when they're making infrastructure utilities for that kind of information to make
investment decisions. Often the conversation wise decisions. Talk a little bit about California
went something like this: we thought about utilities, what's going on there, and PDi2.
underground, but overhead is cheaper, so we
went cheaper. The idea of PDi2 was to form a
team including a diversity of companies with
expertise in different areas, combine
BL There are a number of reasons why
utilities are strategically undergrounding
assets, and that varies by region.
our collective knowledge and best practices,
speak to the industry with one voice, and
help the industry make better infrastructure
investment decisions.

The idea of PDi2 was to form a team including

a diversity of companies with expertise
in different areas, combine our collective
knowledge and best practices, speak to the
industry with one voice, and help the industry
make better infrastructure investment
decisions.

There's a whole set of myths tied to

undergrounding. For example, a common myth
is that if you're in a floodplain, well, water
and cables don't mix, so you can't do that. The
facts are that four feet below the surface of
the ground, there’s 100% condensing moisture.
Cables are operating below ground in water or
moisture for their entire life and the flooding
concern is really a nonissue. People want to
make informed infrastructure investment
decisions, but myths like these get propagated
into rules of thumb which drive poor decisions.
We're agnostic as it relates to overhead versus
underground, but it is clear that much more
education about underground is needed.
Another example is related to cost. In many
cases, legacy rules of thumb drive people to say
the cost of underground is X number of times of
the cost of overhead, so the underground option
isn’t even considered. The reality is the lifecycle
analysis of underground may make more sense
in many more applications than people would
 Transformer Technology May 2023 31

Issue 28

In California, it's the wildfires that are primarily 60-foot-tall trees coming down and taking lines
driving decisions. out, even if they have trimmed the trees.
More and more, there is a recognition that no
But if you look at Florida, it's the hurricanes. matter where you go in the country, if you look
And Wisconsin, they have the emerald ash at the NOAA website, billion-dollar natural
borer and other trees. They have 40, 50, disasters are everywhere.

Source: National Centres for Environmental Information

Photo: Shutterstock
32 FEATURE
INTERVIEW

The Conversation/CC-BY-ND
Source: Krisha Rao 2021
 Transformer Technology May 2023 33

Issue 28

Again according to NOAA, every year, we Apparently, this is where people want to live.
spend something on the order of $20 billion In fact, even after the fires, according to some
on clean up and maintenance after storms. of the organizations that track this, people are
In California, they may not have the ice storms moving back into those areas in droves.
or the hurricanes, but they have the Santa Ana In that interface, the growth rate is higher than
winds, and they have the fires. many other places in the country. Also, about
30% of our population lives in the first county
There's even a term for the areas of high risk – along the coasts, so if you think about that,
the wildland urban interface, the WUI. we apparently want to live in harm's way.
It's beautiful – the oceans, the rivers, the
mountains, but that's where the danger is.
Photo: Shutterstock
34 FEATURE
INTERVIEW

List of coastline counties: http://www2.census.gov/library/stories/2018/08/coastline-countries-list.xlsx

Source: U.S: Census Bureau

Historically, man has decided to live away fault is. You can also use factory comparable
from that kind of danger. I believe, as a society, PD testing to locate and remove the defects
that we're willing to somehow take that risk, before the cable systems are energized.
because we believe it is a reasonable risk. But But even if you have a fault, and you have
all of a sudden, in California you have this large a crew who is trained to isolate and locate
population that's living on that wildland urban underground faults, you're talking about driving
interface and they are trying to figure out a minivan out there to isolate the fault instead
how best to manage a power system that can of one of these large bucket trucks and at ten
ignite fires. So California has a very interesting times lower frequency. Think about how that
situation. Right now they are taking counsel relates to operating maintenance costs. At some
from the ratepayers, utilities, consultants, and investor-owned utilities, they can spend five
they are looking for input. Usually their utility to ten times more on capital instead of O&M
rate cases are on a three-year cycle. Now they and have the same impact on their stock price.
are talking about a ten-year rate case. An If you think about T&D investment from this
opportunity to make a ten-year investment in lens, utilities want to invest in using capital to
underground. I believe California is realizing remove future O&M. So if you have a solution,
that undergrounding has a societal benefit, a albeit potentially more expensive from an
long term benefit. Investment decisions should upfront cost stand point, investor owned
evaluate the "total cost of ownership" of overhead utilities can get excited about this.
versus underground over the life of the asset.
This is how we will get maximum societal benefit.
AR I hadn't thought about that as a case for
underground, but it is. Like anything,

AR Is it more cost-effective from a testing

and maintenance standpoint for
undergrounding than overhead, or is it about
it's the total cost of ownership over the life cycle.
The whole DER thing is – we've been through the
problem of making it cheap, and suffering the
the same? consequences of not doing it right. People were
buying $13,000 transformers instead of $16,000,

BL No, it's dramatically different.

Underground is ten times more reliable
on average than overhead. That's ten times
they saved $3,000. But now you got a gassing
transformer that is significantly more costly to
replace. Anyway, it's bad decisions and myths [that
less call outs. And people will immediately say, don’t’ help], as you say.
oh, but sometimes it takes a lot longer to find
the fault. Well, that was our grandfather's grid.
There are these things called line sensors that
are a technologically advanced and low-cost
BL And it's a lack of information. So PDi2
is all about information. Anything that
we produce from our research, any case studies
way to quickly locate underground faults. that we document, we make that available to
In fact, I think you had one of the companies on the public. We want people to make their own
one of your sessions earlier this year, Sentient decisions, but based on solid information, and
Energy, that has some rather sophisticated not something that's a myth or a rule of thumb
sensors. But there's also fault indicators, very that was made on our grandfather's grid and
simple devices that can triangulate where the perhaps by a siloed group of individuals.
 Transformer Technology May 2023 35

Issue 28

AR What is your exact role with

PDi2?
society need to decide, if we are going to live
in dangerous places, are we also willing to deal
with the climate and weather as it is and tolerate

BL Well, I'm the immediate past chair,

which means I spent the last few years
in the Vice Chair and in the Chairman of the
long grid outages after storms? Also, are we
going to have predictable grid investment, or
are we going to continue to experience surprise
Board position. I am thankful to say that during rate hikes, every three years or so because we
this time we doubled our size. And most of our just had another big storm? Are we going to
growth, at least visible growth, has been in the consider the impact to gross domestic product?
vendor space including consultants, material When the GDP takes a hit, that's actually tax
suppliers, contractors, equipment suppliers, revenue. If we think of the problem from a tax
cable manufacturers, and line sensors. We're base opportunity, it is no longer an issue just for
building this consortium with the companies and the utility and the regulator, it's the legislators
individuals who know how to get it done using that see the impact. For example, Dominion
the latest technology, and even some forward- went and got a rider on a bill that's paying for
thinking technologies, like something as exciting their undergrounding because the legislators are
as using plasma torches to cut holes in rocks and convinced the program helps everybody in the
accelerate trenching, even in the most difficult state.
situations. We have some really forward-thinking
ideas, but also some value we bring is just I believe we as a society need to decide, if
knowing how to do things at scale. For example, we are going to live in dangerous places, are
some of the utilities who advise us and are we also willing to deal with the climate and
building systems at scale are Dominion, I believe weather as it is and tolerate long grid outages
they just announced that they hit 1800 miles after storms?
of undergrounding. WEC Energy Group has
installed 2000 miles. PG&E is saying that they're I would say what's exciting about this
going to install around 10,000 miles and Florida movement and this trend is that people are
Power and Light says 27,000 miles. There is a seeing infrastructure investment as a societal
trend in certain areas where people see that all benefit. It's not just a profitable business
of the benefits are lining up. For example, with scenario, there's a larger societal benefit angle
FPL, they see the gross domestic product of the to the whole conversation.
state as part of the equation.

When you start thinking about the challenge

of infrastructure investment from a societal
AR Next time we're together, I'm going to
ask you about all of that as it relates
to resilience and reliability. But our time's up.
standpoint, all of a sudden, the calculus Thank you so much. Good to see you.
changes. When several life-cycle factors line
up, you're seeing some utilities really jump on
undergrounding in a big way. I believe we as a BL Good to see you again.
Photo: Shutterstock
36 NEW MONITORING
SOLUTIONS

PART 2

NEW TECHNOLOGIES CAN HELP

COMPENSATE FOR THE LOSS
OF PERSONNEL KNOWLEDGE
AND THE INCREASED DEMANDS
ON OPERATING EQUIPMENT

In the last article (March Issue), Intelligent maintenance of power transformers through ETOS®
we described the use and inte- Asset Intelligence
gration of typical sensors with
more analysis and inside-view Monitoring and sensor systems, such as DGA systems, are often installed on
and will now expand the col- power transformers for early fault detection. These can detect operating states
lection and further analysis by and send corresponding messages when limit values are exceeded. However,
edge devices and central solu- the mere attachment of various sensors has two decisive disadvantages.
tions.
Firstly, the sensors generate a lot of data and messages which are not
centrally monitored and evaluated, and multiple events per transformer cannot
be easily monitored and interpreted. Secondly, sensor values are not used
to comprehensively assess a problem. For example, if temperature, partial
discharge and DGA sensors are all capable of detecting winding faults, their
statements are not compared with each other. Thus, contradictory statements
can occur, and a simple diagnosis is not possible.
 Transformer Technology May 2023 37

Issue 28

Transformer health models

Fault
base rates

Bayes net

Sensor false
positive rates

Sensors (e.g. DGA) ETOS® Asset Intelligence User interface

The result is a probability estimate for all known transformer problems with
the most likely problems being displayed to the customer, along with a list of
reasons for the findings. This allows the specialist to interpret the diagnostic
results in a simplified way.

The following example serves as an illustration: The Buchholz relay has trip-
ped and the hydrogen level is greatly increased. Otherwise, there are no further
limit violations. ETOS® Asset Intelligence provides the following findings:
In the central field
device (ETOS®), all
sensors present on the
power trans-former
are integrated and
considered together.
Photo: MR
38 NEW MONITORING
SOLUTIONS

Like a human doctor Due to the accurate fault description, the operator knows how to correctly
who can diagnose classify the fault, assess its criticality, and initiate the next steps. Qualified
through holistic fault diagnoses are provided based on the probability of the most common
assessment, Asset
transformer failures as well as the actual measurements and results. The more
Intelligence for power
transformers provides sensor readings available in the process, the more powerful Asset Intelligence
a guide to minimize is. Like a human doctor who can diagnose through holistic assessment, Asset
risk and take corrective Intelligence for power transformers provides a guide to minimize risk and take
action quickly. corrective action quickly.

By using ETOS® Asset Intelligence, the power system operator can compensate
for the loss of knowledge due to the departure of qualified personnel and make
the asset management of power transformers more efficient.

Global view of a transformer fleet for efficient asset management

Enterprise Asset Performance Management/APM

In times where operative costs must be considered and budget principally

shrink, we look for alternative ways of evaluating the physical health of our trans-
former fleets and adjust strategies to ensure a stable operation of the grid. But
how to manage these requirements and how to deal with a fleet of transformers
that gets older and mostly consists of different suppliers and several variations
over the last years.
We believe in a central solution that covers all online and offline data:
no matter if they are measured in real-time by sensors or if they have been
measured by hand in on-site inspections or while a maintenance. We call this
TESSA® APM and offer a comprehensive system that collects data, checks if
limit values are exceeded, use powerful artificial intelligence to recognize trends
and give recommendations for your asset- and service-management how to
act and what to plan.
We believe in a central
solution that covers all To meet your specific requirements and to match your needs, the system
online and offline data: is adjustable in its integrated functional modules like online-connectivity, oil-
no matter if they are
analysis, asset intelligence and so on – those will be described shortly.
measured in real-time
by sensors or if they
Important is, that the system also has a powerful interface setting that allows
have been measured to use TESSA® APM in combination with a existing database solution of your
by hand in on-site company to exchange necessary data instead of have separated systems in
inspections or while a parallel. That ensures a “single-point-of-truth” methodology and reduces
maintenance. efforts of the personnel.
 Transformer Technology May 2023 39

Issue 28
Photo: MR
40 NEW MONITORING
SOLUTIONS
 Transformer Technology May 2023 41

Issue 28

Condition Assessment
Reliable evaluation standards
- Combine various data sources (including offline
and online data) to gain a clear health index of
your transformer
- Configure weighted indices for condition,
risks and importance to reflect your asset
management philosophy
- Compare to reliable indices defined by MR
according to industry standards and expert
knowledge

Fleet Monitoring
24/7 online monitoring of success critical assets
- Connect sensors for continuous data transfer or
import sensor data manually
- Apply flexible analysis to sensor data
- Detect critical conditions
- Receive automated interpretation of events

Summary

Customer Statements

"We chose MR's system so we could monitor more remotely.

In this way, we save resources and ultimately money.
We also want to understand how components change over time
to better assess service life and necessary maintenance."
Customer testimonial from a power plant operator in southern Germany/Switzerland

Tobias Gruber is Automation Portfolio Mana-

ETOS® ger at Maschinenfabrik Reinhausen GmbH,

where he has worked for 10 years. He helped
develop the current automation systems, i.e.,
EMBEDDED TRANSFORMER OPERATING SYSTEM ETOS® for power transformers. He holds MSc.
in electrical engineering and is an expert for
Photo: MR

automation applications responsible for the

automation portfolio at MR.
42 FEATURE
TOPIC
INTERVIEW
MISSING

Marcel Hilgers
Hossain

Photo: thyssenkrupp
 Issue 28
Transformer Technology

El Hachhouchi
May 2023

Ulrich Voss
Interview with Ulrich Voss Vice President, Marketing and Sales for Power Transformers at SGB-SMIT
Marcel Hilgers Head of Sales, Technical Customer Service and Communications at thyssenkrupp
43

and Hossain El Hachhouchi Manager of Procurement at Enexis

44 FEATURE
INTERVIEW
 Transformer Technology May 2023 45

Issue 28

Alan Ross: I have a delight today. This is not more where I was going for. We're all moving to
your normal one-on-one because we have three try to get to a carbon neutral economy.
people here. I was looking on LinkedIn and I
saw something about a transformer that was Now you're looking at a sub-supply of a major
made by SGB-SMIT. It was made using steel from component of transformers, and you talk to
thyssenkrupp, and it was made for a company Marcel at thyssenkrupp. Marcel, tell us a little
called Enexis. So let me introduce my guests, bit about how, when you were working with
because we're going to talk about that transformer. SGB-SMIT, you came up with the idea – we've got
to do the same thing, because it's not just what
First, this is Ulrich Voss. He is from SGB-SMIT. you did in this project, it is a commitment from
Ulrich, what's your title there? the whole company to be able to decarbonize,
digitalize, and decentralize, right?
Ulrich Voss: The official title is Vice President,
Marketing and Sales for Power Transformers.
For SGB-SMIT, sustainability is really
one of our key drivers towards the
AR And this is Marcel Hilgers. He is with
thyssenkrupp. Marcel, what's your
role there?
future. And a big part of this is CO2.

Marcel Hilgers: Thank you, Alan. I'm pretty

happy about my title because it's not really
MH I think we are on the same mission
in this, the overall electricity
industry. But let's have a quick look into the
a title. I'm taking care of customers, markets steel industry. In the steel industry, we are a
and technology. I am also VP Sales for major polluter. So globally, about 8 to 9% of CO2
thyssenkrupp Electrical Steel Group. emissions are created by steel and iron making.
Therefore, we are a big part of the problem, but

AR Last, but not least, Hossain El

Hachhouchi. Hossain is with the
Enexis. What is your role there, Hossain?
also a big part of the solution. We as a
company have clearly taken commitment
right now. Our target is to decarbonize our
production completely until the year 2045. But
Hossain El Hachhouchi: I'm the manager of we are doing this in steps. Today we already
procurement, responsible for the purchase of have decarbonized the steel solutions available.
all the grid components and IT at Enexis. And for this, of course, we need customers,
transformer makers, and of course, transformer

AR I love the story about how we came

about with the transformer that you
bought. It is very unique: inspirational and
makers need customers. We are looking for
pioneering partners in this big transformation
phase. SGB is a dream partner, so to say, because
aspirational. I want to start off, first of all, with they are really looking forward to decarbonize
you, Ulrich. SGB-SMIT is a big company. You as well. Naturally, we got together about this for
make a lot of transformers and other electrical the first steel with a reduced CO2 intensity to
components. What in the world caused you be delivered to them.
all to think you'd like to be able to produce a
carbon neutral transformer? How did you get
involved in that? Globally, about 8 to 9% of CO2
emissions are created by steel and iron
making. Therefore, we are a big part
UV I would not say carbon neutral, but for
SGB-SMIT, sustainability is really one
of our key drivers towards the future. And a big
of the problem, but also a big part of
the solution. thyssenkrupp has clearly
part of this is CO2. We were thinking a lot about taken commitment right now.
how can we, as a transformer manufacturer,
reduce CO2. As a manufacturer, we can do a
limited number of things. We can produce less
waste, avoid waste, use LEDs. But the main
AR This is brilliant. If they didn't have a
customer, so if thyssenkrupp did not
have a customer, SGB, and if SGB-SMIT didn't
drivers are the customer specifications regarding have a customer, Enexis, none of this would
losses, because low losses over a lifetime make happen. As the procurement expert, you all came
a huge impact. And then there are our sub- along and when they brought the idea to you,
suppliers. One of our main sub-supplier coal- adopted it and said, yeah, we would like to work
based materials is core steel, with a portion of as partners. Talk about when you first heard
approximately 30 – 40%. Therefore, thyssenkrupp about it and your role in creating specs and then
Photo: thyssenkrupp

is with us here in this talk. ultimately saying, we will buy that transformer.

AR To get to carbon neutral, you have to

get lower CO2, so decarbonization is HE Let's begin with the credits where
they are due, because it's an idea that
46 FEATURE
INTERVIEW

actually existed between Ulrich and Marcel. We have some very, very important news
When Ulrich approached us with this idea, for our company. Earlier this year, we have
we were very enthusiastic about it. To lower commissioned the order to engineer and
our CO2 impact as a DSO, we focus mainly on construct the first direct reduction plant with
lowering the loss of energy during transport. submerged arc furnace smelters. This is an
The idea of thyssenkrupp and SGB-SMIT takes investment of more than EUR 2 billion. And
that objective a step further. That's quite here, Alan, is the answer to your question. This
interesting because as a DSO we do encourage solution needs pioneering because there is no
the sustainability production initiatives. But to market for this at the moment. But we know
make a shift, or transition from natural gas or there will be a market. Also, in the future gray
coal to hydrogen, that is a great step and you products will cost more than green products.
need you need the industry. I'm very happy
to see that these two organisations made this
step, especially thyssenkrupp, to be able not
In the future, gray product will cost
only to have a pilot, but to also invest largely in
more than green products.
hydrogen production and using hydrogen in the
process of melting steel. I hope more will follow,
because this is, I think, the only way forward. AR This is happening. It has to come
to what I call scale. But scale is
people like SGB-SMIT saying yeah, we want to

AR I always love to see where the

inspiration came from. As much
credit as we're giving to Ulrich and Marcel, the
participate in this. And you just spoke about
it, Marcel, about the corporate commitment
that you made. That's a huge commitment.
companies that they work for had to make a It also takes a lot of garbage out of the air
commitment. Kudos to your bosses and your and hydrogen in itself can be a problem, so
boss's bosses and the people at the top. you got to do it in a safe way. What is the
commitment not just to this transformer, but
Now let's get down to the basics. How did we get the commitment from SGB-SMIT to this whole
there? I want to talk about the steel first. You pioneering issue?
said you're a big polluter. We don't want people
to know that. We want them to think that steel
is made in a garden where flowers grow. Steel
is a major component to everything we do
UV In a way that we really worked with
thyssenkrupp and we agreed that they
will be the first to bring this to the market. I can
and always will be. Talk a little bit about how only return the compliment – thyssenkrupp
thyssenkrupp got there. How did you decide is the ideal partner for that. We were the first
that you wanted to make a steel that could be bringing this to the market and the question was
used in a transformer that could be purchased which power transformer customer we should
by a customer? start with. There was no doubt, we selected
Enexis. We have a partnership lasting for about

MH Thank you, Alan. We are really in

the biggest transformation of our
company since ever here. Steel has been made
20 years. We supplied so many of these power
transformers to them. Therefore, we introduced
this idea, and they immediately accepted and
for thousands of years, literally, in a blast welcomed it, and also were willing to continue.
furnace process using iron ore and coal as a
reducing agent. A lot of CO2 is created by the
process itself. To give you one figure here, 3.8
metric tons of CO2 is created, in our case, per
AR Hossain, how is the Enexis using
this opportunity to express to your
market the change and the impact on their
one ton of grain-oriented electrical steel. lives? I assume your marketing department is
getting all over this.
Our commitment is replacing all our blast
furnaces. We have four of them, and we make
around 11 million tons of steel, which creates
around 20 million tons of CO2. We want to get
HE Well, our situation differs a bit from
what is common in certain markets.
We are the only DSO in our region. This creates
rid of all of this by applying a new technology a certain responsibility and cost-consciousness.
– direct reduction technology. In the future we This means that it's is very important for us to
will use iron ore, same as before, however, we will keep the prices low. We are very thankful that
replace coaking coal with hydrogen as a reducing SGB was willing to deliver the first unit cost
agent. This means water vapor is coming out of neutral.
the furnace and we have iron sponge coming out
Photo: thyssenkrupp

of this device. Today we already have "fast track" We are absolutely committed to the
solutions, such as feeding existing blast furnaces partnership that we have with SGB, and we
with hydrogen and special scrap as raw materials. definitely embrace the steps that Marcel and
And this is what Ulrich is using with SGB. thyssenkrupp are taking towards pioneering in
Transformer Technology May 2023 47

Issue 28
 48
FEATURE
INTERVIEW

Photo: thyssenkrupp
Transformer Technology May 2023 49

Issue 28

this area, but it also needs some help from the They were saying, we are on board and we want
EU and national governments. to do this, but we need regulations, and we as
an industry need to come together to create
this, as there's too much confusion. Of course,
We are the only DSO in our region. we encourage this, because what is sometimes,
This creates a certain responsibility as a business person first, a bit hard to digest
and cost-consciousness. We are very and understand, is that in the end, it's about
thankful that SGB was willing to deliver decarbonization for our future. It's not so much
the first unit cost neutral. about now, the next business case, competing
and so on. Yes, we are pioneering this and we

AR
of dollars.
There's a price to pay at every level.
Thyssenkrupp is investing billions
will continue with this absolutely, with our
commitment. But we do see, of course, the
whole steel industry moving in Europe, as well
as elsewhere. We embrace this as well, because
We've talked about production and how you're that creates credibility for this product, for the
moving to hydrogen. You all are way ahead of industry.
everybody. You're the pioneer. And remember
what happens to the pioneer. They're the first And it's a good thing in the end, as less CO2 will
ones to get shot. So let's put some protection be emitted. That's what we need.
around you and bring some other people to
the party. SGB-SMIT, thank you for the fact that
you're actually supporting this, because you got
the pressure on costs that the consumers and
AR In the United States, we have an
organization called TMAA, the
Transformer Manufacturing Association of
government puts on an excess. America. They are a lobbying group to the
federal government. I want to give some kudos
Now it's a matter of scale. And I think scale to them, because they caused this Inflation
is coming a lot faster because I know that in Reduction Act which has nothing to do with
the United States we have a thing called the inflation. Steel is going to get some support if
Inflation Reduction Act. It's $345 billion, of they make it carbon neutral. I know we're not
which 40 billion goes to the power industry to there yet, but to get to zero, we have to start
reduce carbon. Canada has also stepped up. here. And you guys have started.
We're getting Latin America to step up. Europe
just passed something on a EUR 58 billion Thank you, Hossain, thank all of your people
approach to hydrogen economy. Ulrich, do you for what you've done. Thank you, SGB-SMIT
have any advice for them? and Ulrich and all your people for what you're
doing. And thank you, Marcel and thyssenkrupp,

UV I wanted to support the statement

about governmental support. We as a
transformer manufacturer need support from
for your commitment to this, because you're
making the world a better place for my
granddaughter.
the regulators, from the government. CO2 needs
to find a way into the specifications in a way that
it is given clear guidance from the top down.

We as a transformer manufacturer
need support from the regulators, from
the government. CO2 needs to find a
way into the specifications in a way
that it is given clear guidance from the
top down.

AR I think Marcel is the one that ought

to end this conversation about the
inspiration of what thyssenkrupp is doing.

MH I have a very fresh experience

here. I'm currently in Italy at a
trade exhibition, which is about the electricity
industry. And I gave a speech about this topic
here – CO2 reduced steel for this industry. In the
audience, there were questions coming which
exactly addressed what you just mentioned.
50 FIELD TESTING
OF CURRENT
TRANSFORMERS

Field Testing of Current Transformers:

Challenges and Mitigation
Techniques
by Dinesh Chhajer
and Ravi Raj Gupta
 Transformer Technology May 2023 51

Issue 28

Dinesh Chhajer received his Master of Sci- Ravi Raj Gupta received his Master's in Ad-
ence in Electrical Engineering from University vanced Electric Power Engineering and Electri-
of Texas at Arlington. He is the Manager of cal Engineering from Michigan Technological
Technical Support Group at Megger USA. University. He is the Substation Applications
His responsibilities include providing engine- Engineer at Megger Americas. His responsi-
ering consultation and recommendations in bility includes providing technical and engi-
relation to testing of transformers, circuit neering support for various testing equipment
breakers and other substation assets. He has manufactured at Megger. His area of focus is
presented several white papers related to testing equipment that primarily help in testing
asset maintenance and testing at various Transformers, Circuit Breakers, and other Sub-
conferences within power industry. He has station assets. He has previously worked with
previously worked as an Applications Engi- Siemens as a Lead Application Engineer and a
neer at Megger and substation and design Business Development Manager for their Volt-
engineer at Power Engineers Inc. He is cur- age Regulators product line within their Trans-
rently a licensed professional engineer in the formers division. He holds an Engineering in
state of Texas. Training certification from Michigan.

Introduction IEEE Recommendations for

Testing relaying Type CTs
Current Transformers (CT), circuit
breakers and relays are key IEEE Power Engineering Society
components of the protection and recommends certain field tests to
control systems. Reliability of a measure relaying type CTs. These tests
protection system depends on are designed to verify proper operation,
the performance of these devices. connection, and condition of the CTs.
Periodic testing of these assets IEEE Standard C57.13.1, “IEEE Guide
ensures that the protection circuit for Field Testing of Relaying Current
that will operate as needed. Transformers”, Reference [1] outlines
the intention for the designated
Bushing Current Transformers tests as well as the test procedures.
(BCTs) on power transformers and The recommended tests are: Ratio,
circuit breakers are tested as per Polarity, Insulation Resistance, Winding
IEEE recommendations to verify Resistance, Excitation, Admittance,
their performance and ensure and Burden Test.
that they meet manufacturer’s
specifications. Testing BCTs is Field Challenges of BCTs in
challenging when they are under EHV Environments
overhead energized lines, as
induced voltages on these EHV environments can compound
bushing terminals affect measure- difficulty of testing BCTs. This is
ments, this is more pronounced a result of a variety of factors, but
when testing is performed in EHV the most influential is the elevated
stations. This article recommends level of induced voltage. U.S. electric
field practices to overcome this utilities operate complex transmission
Photo: Megger

issue and guides in how to evaluate systems at voltages up to 765 kV.

the results. These EHV power lines interact with
52 FIELD TESTING
OF CURRENT
TRANSFORMERS

external objects to create capacitive,

inductive, and conductive coupling.
This results in induced voltage that
can reach several kilovolts. This
voltage can be calculated using the
equation (2) listed in reference [3]:

When testing a BCT, the bushing

terminals can be left open, effectively
insulating the tested equipment from
ground. When this occurs, the open-
circuit voltage that is induced can
be calculated using the equation (3)
listed in reference [3]:

Where,

VLL= line voltage between phases (kV)

ho = height of the object above
ground (m)
hj = mean height of phase
conductor j (j = 1, 2, 3) (m)
djo = distance between phase
conductor j and object (m)

This induced voltage makes testing

BCTs extremely difficult, especially
for verification of ratio and polarity.
The addition of stray voltage on
any floating bushing terminals will
drastically change the voltage on the
primary winding, making it impossible
to accurately measure voltages on Figure 1: Secondary winding impedance
the primary. This has been verified Connections to primary and secondary side of when referred to primary side can be
by field measurements that result in the CT for ratio and polarity test
represented by an equivalent circuit
ratio errors in excess of 10-20%. as shown in Figure 4.
Interference Suppression
Interference and Noise Methods Here,
ZP = RP + j * XP
IEEE recommended field tests on Transformer equivalent circuit, as per Zm= RC || Xm
relaying class CTs are mostly Figure 3.
N 2
performed by the secondary voltage Zs'= (___1 ) * (Rs+ j * Xs)
N2
injection method because of the Primary winding resistance RP and
ease of connections and instrument primary leakage reactance XP
portability. Measurements for tests For any transformer, magnetizing
such as excitation, winding resistance, Secondary winding resistance RS and impedance Zm is much larger than
inter core coupling and burden are secondary leakage reactance XS primary winding impedance ZP and
primarily taken on the electrically secondary winding impedance Zs’.
isolated from the primary side, Core loss component RC and
interference negligibly affects these magnetizing reactance Xm Zm >> ZP or Zs
tests, and provides acceptable results.

In Figure 1, ratio and polarity tests are

the tests where the test instrument’s
primary side leads are connected to
the bushings of the BCT under test.
Since the voltage induced in the CT
primary when using secondary test
voltage method is just a few volts, it is
challenging to measure it accurately
under the influence of external Figure 2:
electrostatic interference. Transformer exact equivalent circuit
Transformer Technology May 2023 53

Issue 28

To reduce error in the measurement,

reduce the impedance or inductance
of the circuit. Under an open circuit
condition, the impedance seen by
the measuring circuit (as viewed
from H1-H2 terminals) is primarily
magnetizing impedance as shown in
Figure 5. Under an induced voltage Figure 3:
condition on the bushing terminals, Transformer equivalent circuit as referred to primary
this can lead to an undesired voltage
drop in the measuring circuit and
can lead to a ratio error outside the
tolerances.

To reduce the impedance of the

circuit, it is recommended to short
the corresponding secondary winding
of the transformer as shown in the Figure 4:
Transformer circuit impedance under open circuit condition
diagram below.

With the secondary winding short

circuited, the impedance seen by
the measuring circuit is reduced to
the primary and secondary winding
impedance. The voltage drop across
winding impedance is much lower,
and this helps in reducing the ratio Figure 5:
and phase angle error. Transformer circuit impedance under short circuit condition

When working under high voltage

energized lines, the induced voltage of any induced stray voltage on the testing BCTs on different transformer
on the bushing terminals and high floating terminals and depending configurations:
inductance of the transformer upon the winding configuration,
winding together can create a it would further reduce the overall 1) Testing H1 BCTs of a transformer
problem. Any induced voltage would impedance of the measurement with delta winding configuration
cause leakage or stray current circuit. is shown in Figures 6 and 7.
through the circuit and with high Connection configurations for all
impedance it would create a higher The following diagrams depict the the delta winding bushings are
voltage drop, thereby affecting recommended connections for given in Table 1.
the measurements. Therefore, in
addition to shorting the secondary
winding it is recommended to ground
the bushing terminal corresponding
to the BCT under test to guard
against any induced voltage due
to coupling effect. Technicians
operating the test instrument
should be careful in implementing
smart grounding principle and Figure 6:
avoid any possibility of ground Connection diagram for testing primary side BCTs for a delta-wye configuration
loops which can create a circulating
path and influence the current
flow in the measurement circuit.
It is important to note that only
one terminal should be grounded
on high voltage bushing terminals
to suppress the interference from
overhead energized lines. It is
also recommended to connect the
unused bushing terminals to the
return path H2 lead. This serves Figure 7:
two purposes; it reduces the effect Connection diagram for testing primary side BCTs for a delta-delta configuration
54 FIELD TESTING
OF CURRENT
TRANSFORMERS

BCT under Test H1 lead H2 lead Ground Jumpers H side Jumpers X side

H1 H1 H2 H1 H2, H3 X1, X2, X3 and X0 (if available)

H2 H2 H3 H2 H3, H1 X1, X2, X3 and X0 (if available)

H3 H3 H1 H3 H1, H2 X1, X2, X3 and X0 (if available)

Table 1:
Connections for each BCT for a delta configuration winding

Figure 8:
Connection diagram for testing primary side BCTs for a wye-wye configuration

2) Testing H1 BCTs of a transformer

with wye winding configuration
is shown in Figures 8 and 9.
Connection configurations for
all the wye winding bushings are Figure 9:
given in Table 2. Connection diagram for testing primary side BCTs for a wye-delta configuration

BCT under Test H1 lead H2 lead Ground Jumpers H side Jumpers X side

H1 H1 H0 H1 H2, H3, H0 X1, X2, X3 and X0 (if available)

H2 H2 H0 H2 H3, H1, H0 X1, X2, X3 and X0 (if available)

H3 H3 H0 H3 H1, H2, H0 X1, X2, X3 and X0 (if available)

H0 H0 H1 H0 H1, H2, H3 X1, X2, X3 and X0 (if available)

Table 2:
Connections for each BCT for a wye configuration winding

3) Testing H1 BCTs of a single-phase

auto transformer with tertiary
winding is shown in Figure 10.
Connection configurations for
all the bushings of an auto
Photo: Megger

transformer with tertiary are given Figure 10:

in Table 3. Connection diagram for testing high side BCTs on an auto transformer with tertiary
Transformer Technology May 2023 55

Issue 28

BCT under Test H1 lead H2 lead Ground Jumpers Primary side Jumpers Tertiary side

H1 H1 H0 H1 X1, H0 Y1 and Y2

X1 X1 H0 X1 H1, H0 Y1 and Y2

X0 X0 H1 H0 H1, X1 Y1 and Y2

Y1 Y1 Y2 Y1 H1, X1, H0 N/A

Y2 Y2 Y1 Y2 H1, X1, H0 N/A

Table 3:
Connections for each BCT of a single-phase auto transformer with tertiary

Case Study

The company in proximity of

overhead energized lines and
inductance associated with large
windings of power transformers
were finding it impossible to test
BCTs on transformers in their 765
kV substations. The results obtained
were inconsistent and unreliable
because of copious amounts of error
in the measurements. This utility
which owns North America’s largest
transmission network and operates
numerous 500 kV and 765 kV stations,
was looking to develop a complete
and effective solution to this.

A crucial part of the commissioning

process for power transformers in
EHV substations is the testing of
BCTs. A 765/500/13.8 kV, 750 MVA Figure 11:
single phase auto transformer with Picture showing the testing under energized lines and rainy condition
seventeen BCTs was tested in an
energized EHV substation during
BCT 1 2 3 4 5 6
inclement weather conditions as
shown in Figure 11. 3000:5 3000:5 1000:5 3000:5 3000:5 1698:5
H1
C800 C800 0.15S B1.8 C800 C800 C800
As shown in Table 4, a total of 3000:5 3000:5 3000:5 3000:5
seventeen BCTs mounted on X1
C800 C800 C800 C800
different bushings of a single-phase 3000:5 3000:5
auto transformer with tertiary were X0
C800 C200
tested for all the IEEE recommended 3000:5 3000:5 4963:5
tests. Y1
C800 C800 C200
3000:5 3000:5
With cloudy and rainy weather Y2
C800 C800
conditions along with the nearby
energized lines, conditions were not Table 4:
ideal, where a small measurement BCT with different classes and ratios mounted on different bushings
error (in the mV range) of high side
voltage could have easily thrown When performing the primary to warning message. The presence
the ratio readings off. Insulation ground insulation resistance test, the of induced voltage and size of the
resistance was first performed as test instrument detected a presence transformer gave indications that
per the recommended connections of live voltage on bushing terminals test results might get influenced and
in IEEE Standard C57.13.1. and gave a “live voltage present” would pose a challenging situation.
56 FIELD TESTING
OF CURRENT
TRANSFORMERS

As shown in Figure 12, connections to

the bushings were made by bringing a
wire from top of the bushing for easy
access. The test was first carried
out by connecting the leads in a
traditional way. Connection, H1 lead
to the H1 bushing and the H2 lead
to the H0/X0 bushing. All other tests
were performed on the BCT without
any difficulty. While performing the
ratio and polarity tests, readings
would not stabilize on high side
terminals and manually recording the
results gave a ratio error of 20-23%.

To ensure that repeatable and

accurate measurements are obtained,
three actions were taken:
Figure 12:
• Reduce the effect of electrical Picture showing the location of each bushing
noise and electrostatic interference on single phase auto transformer with tertiary
from overhead energized lines by
grounding the bushing of the BCT
under test.
• Short the secondary and tertiary
winding (separately) to reduce the
circuit impedance.
• Short all the floating unused
terminals and connect to the return
path (H2 lead).

Using the connections shown in

Figure 13, testing was repeated, and
consistent results were obtained for all
the tests. The following results were on
a C800 3000:5 multi-tap CT mounted
on the H1 as shown in Figure 14.

Based on the connections applied Figure 13:

for the first BCT, the others were Connection diagram for testing BCTs on single
tested using the same procedure and phase auto transformer with tertiary
accurate results were obtained on
all the BCTs. The results obtained on
C800 5000:5 BCT mounted on tertiary
winding Y1 bushing are shown in
Figure 15.

Three other transformers in 500 kV

and 765 kV substations were tested
with the same concept and all the
CTs ratio and polarity measurements
were obtained with high accuracy
and repeatability. Overall, more than
fifty CTs were tested with the same
procedure.

It was noted when working with lower

inductance transformer windings
where there is little or no interference,
some of the recommended steps
Photo: Megger

above could be skipped and reliable

measurements are still obtainable.
Transformer Technology May 2023 57

Issue 28

Figure 14:
Ratio and Saturation results of H1 BCT

Figure 15:
Ratio and Saturation results of Y1 BCT
58 FIELD TESTING
OF CURRENT
TRANSFORMERS

Conclusion References
[1] “IEEE Guide for Field
Test cases verify effective grounding Testing of Relaying Current
and isolation techniques can be Transformers”,
used to safely obtain highly accurate IEEE C57.13.1- 2006
measurements on BCTs in less- [2] Diego M Robalino,
than-ideal environments by “A Comprehensive Approach
eliminating electrostatic build up. to Current Transformer Field
This paper outlined measurement Diagnostics”, TSDOS 2014.
techniques for various winding [3 Abdel-Salam, Mazen, Hussein
configurations to reduce noise and Anis, Ahdab El-Morshedy,
interference seen in EHV substations. and Roshdy Radwan, “High-
Reduced interference levels provided Voltage Engineering: Theory
near perfect accuracy. This allows and Practice”, 2nd ed. New
for precise testing of BCTs as York: M. Dekker, 2000.
outlined by IEEE.

Photo: Megger
Transformer Technology May 2023 59

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Issue 28

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60 FEATURE
INTERVIEW

Prabhat Jain
 Transformer Technology May 2023 61

Issue 28

CEO-CTO of Virginia
Transformer Corp
In our country, our biggest
challenge is finding people,
especially people who
have STEM backgrounds.
One of the things I have
done is hire engineers just
straight out of college and Interview with Prabhat Jain

then utilize them more on

the shop floor. That way,
they are able to get their
hands on the product.
Photo: Prabhat Jain
62 FEATURE
INTERVIEW

Alan Ross: I have a guest today is one I've had workers, and operators, I need 100 engineers
many times before. Prabhat Jain is the CEO and on the floor. It's a realization after many years
the steering influencer of Virginia Transformer, of saying, Why can't we improve our quality
Georgia Transformer. Prab, the first time we beyond where we were five years ago, three
talked, it intrigued me so much because we were years ago? We reached a plateau of what we can
in the middle of the COVID supply chain issues. do with the labor force available and how much
We also talked about a different approach to we can train them. The next level to rise would
transformer manufacturing that was needed be by engineers complementing the operators.
for all companies. It involves staffing, it involves This is my solution going forward, to continue to
technology, it involved a lot of areas that you write the increase in our quality first pass yield,
have implemented at Virginia Transformers. Tell doing it right the first time, building the product
me a little bit about how things have developed correctly, and following the prints correctly.
since then. It's a huge investment in terms of personnel
and in terms of management to oversee these
Prabhat Jain: Alan, in our country, our biggest personnel, but that is what it takes to ensure
challenge is finding people, especially people the quality of our custom-built transformers.
who have STEM backgrounds. One of the things Because not only does it give you better quality
I have done is hire engineers just straight out in the plant and a better product for the
of college and then utilize them more on the customer, but it is more satisfying for the people
shop floor. That way, they are able to get their that work in the plant. That is the bigger benefit
hands on the product. I have also transferred of this. Because they are successful, we are
people from our Mexico plant to our plant here successful. They feel happy and satisfied. We
in the US. We've hired about 100 engineers from haven't had a failure for the last hundred units.
Mexico, and they have come to the US on what I started the project last year. This year we'll be
we call the TN visa. They are electromechanical getting some output, getting some traction, and
engineers and they are working on the winding making an impact on the quality continuously.
machines. They do an assembly of 500 MVA And in the next three to five years, we will
transformers and learn about a new state-of- continue to rise up on that curve of quality. And
the-art, highly automated, and sophisticated over a period of time, I'm sure we're going to do
core-cutting machine that requires engineers even better.
to run it. We have also hired about 40 local
engineers in our three US Plants. And in our
Mexico plant, we have hired about 50 new I realized probably about two
engineers in the last six months. We are bringing or three years ago that the
more engineers onto the production floor.
demand for transformers with
At the same time, we started a program that we renewable energy battery
call EPI Three, which is Equivalent Proficiency storage and then data centers
Index Three. That means in one year, we get
the person to become proficient, equivalent to
are going to be so huge that
a three-year person. It works like this: For six the supply simply isn't there.
months out of the one year, they train full-time. And there's going to be about
We retrain them, reinforce, educate them, and
then we actually have places where we build
15 of those all over the world
a transformer in an educational function. We and of course, many others
have winding machines and actual transformers that are happening. There is so
which are used for teaching people how to build
a transformer. So they build it and we take it
much demand for transformers
apart and build it again. Hands-on crimping and and nobody is building up
torquing and sealing, on a real product. Not the more capacity. Lead times are
one that is going to be shipped to the customer,
of course, but a practice product.
growing longer and longer.
That's why I launched my plan.
There are three prongs to this. One is to bring
engineers on the floor and bring engineers The other project we launched is automation.
from Mexico, because there are plenty of I'm starting a robotic lab. We launched it last
engineers available there. They progress from year. We have hired wonderful engineers. They
there to become technical leaders of the plant go to school and do robotic engineering and
as technicians, quality engineers, process we hire them straight from out of college. And
engineers etc. I've established a goal that 20% of these young people will give you all these ideas
the personnel in the manufacturing operation and projects to do fun things. We send them to
must be engineers and technicians. If I have 500 the shop to start trying out stuff and see what
 Transformer Technology May 2023 63

Issue 28

you can automate. So it's really a lab, and it's so

exciting. I think in about two years, we would This year we'll be getting some
have some robotic applications in transformer output, getting some traction,
making, which will be the first in the world.
Very few robots are used in transformer making.
and making an impact on the
quality continuously. And in
the next three to five years, we
AR Everything you're talking about
is really cutting-edge. I know
transformer manufacturing very well, and we've
will continue to rise up on that
gotten into this old mindset in the industry curve of quality.
that that's the way we've always done it. And
maybe they make minor changes here or there
but you're talking about major changes. As an
engineer, I would love to come to work for you,
AR I couldn’t agree more. I want to go
back to the plant you opened in
Mexico, in Chihuahua, and I'm glad you said that
except I'm retired, so I can't. But we engineers it's not just a separate isolated thing but part of
have a passion for making things better. this collaborative project you have described.
Why Chihuahua? When is it opening?

PJ Yes, you certainly do. We have hired six

PhDs in the last nine months. And you
will be surprised but they are chemistry and PJ I realized probably about two or
three years ago that the demand for
physics PhDs. You would wonder why I would transformers with renewable energy battery
need chemistry and physics PhDs, but those are storage and then data centers are going to be
basic sciences. They will help me a lot, and they so huge that the supply simply isn't there. And
are solving problems. They are coming up with then I estimated one time that we're going to be
ideas on how to better cool the transformer, how falling short on the pad-mounted transformers
to better secure the transformer against oxidation in the world by 20,000 transformers a year. And
and then moisture generation. Scientists can do that's just a narrow estimate from what I could
anything. Engineers can do anything. And you gather. And then nobody is putting up plants
just have to give them a vision, let them loose, and for pad-mounted transformers, at least in North
they will go solve problems. America.
Photo: Virginia Transformer Corp
64 FEATURE
INTERVIEW

I also realized about a year ago, that we are There is nothing overhead. Cranes can run
decoupling from China and that decoupling freely everywhere. Everything is lifted by the
from China would mean that we really have to crane by robotic platforms. You can move them
do a lot of production at home. And then that with the remote control, and you can gear them
production is going to be everything. It's going anywhere you want them to go. They carry
to be steel, cement, and paper, it's going to be the transformer from one station to the other
pharmaceuticals, and then cars and batteries station for work. The plant is also fully air-
and semiconductors. So that's a huge push. conditioned. And it is only the second plant in
This 40 billion semiconductor plant that Taiwan North America that can boast that. Our Georgia
Semiconductor is putting in Arizona alone is factory is fully air-conditioned as well. That
going to require roughly $300 million worth of gives you a very dry, very reliable transformer
transformers. There's a brand-new application insulation system. There was a company in
because it wasn't there three years ago. There Mexico, that was there for 70 - 80 years, and
is the technology that is coming along on the when they closed, we hired all their engineers.
energy side where they want to electrolysis, These were shop managers and manufacturers
separate the hydrogen from water and they're with 20 - 30 years of experience and we hired all
going to combine it with carbon dioxide from of them and brought them to our plant.
the atmosphere and make synthetic fuel.
there's. The first project of this going up in Texas, In addition to this small transformer, I then
and it’s going to require $500 million worth of added a line in there for medium power. We can
transformers in the next three years. Just that build up 200 MVA in that plant now. 230 KV,
one project. And there's going to be about 15 of 100 MVA. This is important because there are
those all over the world and of course, many seven LNG terminals being built in our country
others that are happening. There is so much right now, and each one of them requires $500
demand for transformers and nobody is building million worth of transformers over a period of
up more capacity. Lead times are growing longer about seven to eight years. That is huge. Our
and longer. That's why I launched this plan. new plant went into operation in October and
the medium power line is already backlogged
Initially, this plan was only to build small for 50 weeks. In just three months, we have
transformers because I saw that 20,000 gotten so much demand. So think about one
shortage. However, I started to think about it, thing: If this plant wasn't there, where would
meet customers and listened to the energy they get those transformers from?
specials and interviews of the CEOs that they
do on Bloomberg. And I started realizing the
demand for medium power and large power
transformers in our country is going to grow
AR The lead times would grow even
longer.

because of the decoupling with China and the

energy revolution. So we are really building
the industrial infrastructure in our country to
PJ And what does this mean for the country,
Alan? As a country, we wouldn’t be able
to do these projects. They would have to be
support the new manufacturing and the new postponed by one year. That means you hold
energy demand. That is why we have launched back the progress for one year. I mean, that's the
this plan. It took somewhere around 15-16 impact. So that's why I'm doing what I’m doing.
months to build. It's amazing what they have So we can give you transformers now, so we can
been able to do in such a short time. develop synthetic fuel now, so we can build our
LNG terminals now to export the gas that we are
now flaring in the atmosphere. We can keep that
In addition to this small and convert it into liquid and then send it to
transformer, I then added a Europe. They need gas over there.
line in there for medium power.
This is important because
there are seven LNG terminals
AR Absolutely.

being built in our country right

now, and each one of them
PJ This is what I've been able to do with
these new plants. And my managers, the
leaders of the company, know that it isn’t just
requires $500 million worth of about building transformers and expanding our
transformers over a period of business. This is about helping our country to
maintain and develop our infrastructure and
about seven to eight years. become more self-reliant. That's so important.

It's all state-of-the-art: All the wiring is

underground, and the piping is underground. AR I'm with you. Now, there's another
side effect. You kind of mentioned it.
 Transformer Technology May 2023 65

Issue 28

There was the Mexican plant that closed and rapidly than we thought it was going to because
all those people lost their jobs. Now they have we've been looking at where transformers are
jobs again. What is this doing in Chihuahua? It's and not where they are going to have to be in
got to be having such a positive impact on that the future. EV charging alone is going to change
community. the demand curve. The transformer is the heart
of the power system anywhere and we've got

PJ The governor of the state, the mayor,

and the secretary of the state, they're so
energized by our design center. We have 200
heart surgery going on because we have a lot of
aging transformers that we've got to take out of
service. They're going to fail catastrophically if
engineers in the design center now over there. we don't do something.
They say this is wonderful because not only are
we giving jobs to the people who make harnesses You got life cycle planning. You've got this
because that's what most of the American plants demand curve increasing rapidly. But at the
do there, but we are building a real product there same time the need for quality. It seems to me
with real engineers. We do engineering there for you're addressing a lot of issues. When is the
us, the Mexican engineers are building products, plant officially going to have a grand opening?
and designing products for us. So the folks in

PJ
Chihuahua are so energized. The leaders are We held a ribbon cutting ceremony on
saying this gives a big status to them. We created 10 February. It was really just to mark
600 new jobs in Chihuahua in the last six, or nine the event. Basically, the plant has already
months. The standard of living in Chihuahua is produced and shipped its first transformers. But
rising so fast. They have a brand-new district on February 10, about 40 people from Virginia
now with shopping areas, cinemas, restaurants, Transformers went down there to see and feel
and so forth because the standard of living has connected and be proud of what the extension
gone up so much in such a short time. And not of Virginia Transformers is. And of course, the
only that, the education is so good. The engineers local people were there, the officials like the
have respect for the company’s process and mayor and secretary. Customers attended as
they follow it. That's one thing I think they have well as our partners across our supply chain.
an advantage over Americans. They follow

AR
the process. Because they have respect for the Make sure you get some really good
company, the managers, and the standard. I find pictures because I'm going to do a
that to be a differentiator. story on the grand opening and we're going to
publish it because I would love to promote what

We created 600 new jobs in you're doing. I think it's brilliant work.

Chihuahua in the last six, or

nine months. The standard of PJ Absolutely. I think it's going to help our
country a whole lot.

living in Chihuahua is rising

Photo: Virginia Transformer Corp

so fast. AR Prabhat, I love what you're doing.

Everything you've talked about
valuing people to create value for the

AR Everything that you said today you

are completely right about. It's no
marketplace. You are doing outstanding work.

longer a supply chain issue. It's a demand curve

issue. The demand curve is changing far more PJ Thank you very much. I appreciate the
opportunity to give my thoughts.
66 AI AND ML IN
TOPIC
DATA ANALYSIS
MISSING

Looking backward
to see a way forward
Photo: Shutterstock

by Tony McGrail
Transformer Technology May 2023 67

Issue 28

As we move towards greater If you read the limitations for ChatGPT

application of, and reliance on, on the landing page it does say:
Artificial Intelligence and Machine - “May occasionally generate
Learning (AI/ML) systems, it’s worth incorrect information”
noting that there are some activities - “May occasionally produce harmful
where they perform well, and some instructions or biased content”
where they perform poorly. Recent - “Limited knowledge of world and
experiences with large language events after 2021”
models (LLMs) such as ChatGPT (1)
have shown that it is going to be So we proceeded with caution as we
Tony McGrail is Doble Engineering Company’s
some time before the machines are dealing with some HV bushings and
Solutions Director for Asset Management &
take over from humans in analyzing ‘What’s the worst that could happen?’ is
Monitoring Technology, providing condition,
anomalous condition monitoring actually quite bad: catastrophic failure
criticality and risk analysis for utility compa-
data and are able to extrapolate from of the whole GSU power transformer
nies. Previously Tony has spent over 10 years
experience: looking backward to with associated consequences: fire,
with National Grid in the UK and the US; he has
predict the future. safety and environmental issues,
been both a substation equipment specialist
system disruption and so on.
and subsequently substation asset manager,
I had heard that AI/ML tools can do
identifying risks and opportunities for invest-
all sorts of clever stuff, so I asked The data in Figure 1 is real, and
ment in an aged infrastructure. Tony is a Fel-
ChatGPT if it could help with some disturbing: why would a current rise
low of the IET, a member of the IEEE, CIGRE,
bushing data I’d collected from an on then fall, repeatedly? Could it be a
ASTM, ISO and the IAM, and is currently active
line condition monitor: it seemed like problem with the monitor itself? What
on the Doble Client Committee on Asset and
a good idea as ‘What’s the worst that does it mean? the question I asked
Maintenance Management and a contributor
could happen?’ The case was a real ChatGPT was: “If I am monitoring a
to SFRA, Condition Monitoring and Asset Man-
one, with the data for one bushing bushing and the leakage current rises
agement standards. His initial degree was in
plotted below, Figure 1, showing sharply, but then falls rapidly back to
Physics, supplemented by an MS and a PhD in
leakage current rms magnitude nominal, then rises again, and falls
EE followed by an MBA.
hourly; the data shows anomalous again, then stabilizes close but just
behavior – but what does it mean? above nominal, what should I do?”

Figure 1: Raw Bushing rms Current Data Recorded hourly

68 AI AND ML IN
DATA ANALYSIS

I must admit that I wasn’t expecting

much in the way of a response and
what I got started with the expected
generic response that there ‘could be
a problem which needs investigation’
genre, as shown in Figure 2:

lt is important to investigate the cause of the repeated pattern of rising and falling leakage
current. This could be an indication of a developing fault within the bushing or the
surrounding equipment. Depending on the severity of the issue, it may be necessary to take
immediate action, such as isolating the equipment, shutting down the system, or conducting
a thorough inspection.

Figure 2: Response as expected – broad statements of a possible problem

But what I was not expecting was the

caveat that came with it, given in Fig 3.

ln any case, it is recommended that you consult with a qualified electrical engineer or
technician who is familiar with the equipment and can previde specific guidance on how to
proceed. lt is also important to follow any applicable safety procedures and guidelines when
working with high-voltage equipment.

Figure 3: ChatGPT caveat in terms of condition monitoring data analysis

After basically saying “I don’t know Problems such as: Noam Chomsky who has an insight
what this is” in Figure 2, ChatGPT - ‘Giraffing’: where the system detects into the use of language to train and
suggests checking with a qualified giraffes in supplied pictures even apply AI systems:
electrical engineer/technician: this though there are no giraffes present
seems to be an eminently sensible - Bias: usually based on the original
“There is a notion of success ...
idea. Whatever expertise ChatGPT data being biased, for example,
has, it does seem to ‘realize’ its own looking for a reliable transformer
which I think is novel in the history
limitations. And checking with SMEs is and preferring Manufacturer X to
exactly what we did when we reviewed Manufacturer Y based on limited
of science. It interprets success as
the original data: checking with people failure statistics which don’t reflect
who know what they are doing. If you the real world
approximating unanalyzed data.”
are interested in what the data means, - Misapplication: training a tool to
and what happened next, I’d be happy distinguish between pictures of cats
to share: suffice to say it’s an unusual and dogs, and then trying to identify
case but the bushing remained in a llama… What is common
service for more than 12 months more. - Not having a good indication of
why the AI makes the decision it to AI/ML models
does: it’s worth noting the case of
Whatever expertise an X-ray interpretation tool which is that they build
performed well, but which made
ChatGPT has, decisions based on the type of X-ray on example data –
machine that was used, rather than
it does seem to the detailed content of the X-ray (3) base data, training
‘realize’ its own The cause of these mistakes may data, historic data –
be through inappropriate ‘training’,
limitations. or application to data which is not to identify/classify/
related to the original data, or which
When successful, AI/ML can look like are the result of inflated expectation analyze ‘new’ data.
magic: performing well at picking out in the user, and so on. What is
faces in a crowd, say, or analyzing common to AI/ML models is that And therein lies the problem – an
lots of data extremely rapidly and they build on example data – base AI/ML tool is usually very poor at
Photo: Shutterstock

consistently, but they can also show data, training data, historic data – to extrapolating from whatever data it
bias, make mistakes, and reach identify/classify/analyze ‘new’ data. has ’seen’ in order to make sense of
unsupportable conclusions (2). And, to quote the language specialist what it hasn’t seen previously.
Transformer Technology May 2023 69

Issue 28

75ppm to >120ppm in a few hours. In

the second case, a relatively flat trend
suddenly steps up from ~20ppm to
almost 120ppm in a few hours.

The two DGA cases, are, in fact,

sister transformers: same
manufacturer, both 48MVA, both
over 30 years old, rarely fully loaded
but some indications of overheating
in the DGA and FFA levels. The
trans former in Figure 4 was taken
out of service a few days later,
tested using standard tests, and an
internal inspection confirmed severe
overheating and likely imminent
failure of LV lead connections –
which had been undersized from
the initial manufacture: if it had
stayed in service, it could have failed
catastrophically.

And the transformer in Figure 5?

It was returned to service after a prior
maintenance outage, but with

Figure 4: Composite DGA with a rising trend and a sudden step change

It is an interesting side-note that an try to classify new data but make a

estimated 95% of the benefits of AI/ check as to whether the new data
ML can be achieved through standard looks like previously available data,
statistical and data analyses on and calculates an ‘out of distribution’
the raw data, but that is to miss the (OOD) value (6). If the OOD means
point that the other 5% may be vitally it doesn’t look like something we’ve
important (4). We don’t know until we seen before, ask for a relevant
look! BTW, side-note 2: the idea that specialist to check: that is, ask
we just get more data and throw it all someone who has domain
at a bigger AI/ML system is usually knowledge, experience and can
a bad idea, wasting time and effort interpret data.
and resources: it’s best to start with
a small system which can grow and What else? Context is extremely
build on success (5). important, as demonstrated by
the following two examples of
So, we need to understand the data composite DGA monitors, giving
we have available: what did we a representative ppm value for
train the AI/ML on, and does a new combustible gases dissolved in
piece look at all like that? There are transformer oil. In Figure 4 we can
examples of AI/ML classifier tools see a gently rising trend over several Figure 5: Composite DGA with a ‘flat’ trend
which, in the first instance, do not days, and a sudden rise from about and a sudden step change
70 AI AND ML IN
DATA ANALYSIS

the cooler return valve closed: and the cases where real experience the engineers, not replace them: use
subsequently, there was a temperature is needed are fewer, but the ‘edge’ the tools to identify where SMEs can
alert as the cooling was not cases aren’t going away. And with most profitably spend their time.
functioning, and the rise in monitored the growth in DERs, and the increase Initially the pure data scientists
DGA was a result of the cooler valve in the need for condition monitoring, complained about the data ‘It
being opened and fresh oil reaching there is a corresponding need for must be wrong as it doesn’t fit our
the DGA sensor: the transformer was humans who understand the data and models’, but after some ‘learning’
actually de-energized at the time. How can look for answers which may lie on both sides, the resulting hybrid
do we get all of that type of information, outside the box: such as would apply approach provided great value to the
context, and insight into an AI system? to the bushing in Figure 1. organization (7). And it may be that,
That is going to be a challenge. over time, the number of cases which
the AI/ML passes over to the SMEs
At DistribuTech this year, there was Over time it may reduces, as the AI/ML learns, but that,
a significant number of companies too, will take time.
offering AI/ML tools as part of their be that AI/ML gets
offerings: OEMS, consultants, service So, in the interest of experimentation,
companies, data companies, and so more adept and I did ask ChatGPT many other
on. What is perhaps most encouraging questions, but one sticks in my mind:
is that many of them understood the cases where “Can you give me some anagrams of
quite clearly that while they may find ’Transformer Bushing’?”. It shouldn’t
interesting relationships or trends real experience is be too difficult to rearrange 18
within supplied data, they also need letters into something interesting for
the capability of industry experts to needed are fewer, a system with the language skills
give meaning to the findings. This is a of ChatGPT, and it came up with
challenge when we are losing capability but the ‘edge’ several, but my favorite was “The
through retirement or career changes, Grim Buffoons Runes”. This may
and have fewer people than needed cases aren’t going seem pretty good, but it has a couple
entering the industry each year. And, of extra letters, meaning it fails the
of course, new industry individuals will away. basic definition of what an anagram
take some years before becoming the is… sometimes you have to get the
SME’s of the future. AI/ML can fill some The work of Tom Rhodes and simple stuff right, like counting letters,
of the gap, but not all of it – over time colleagues at Duke Energy is highly before doing something difficult like
it may be that AI/ML gets more adept relevant – applying AI/ML to support rearranging them into new words.

Photo: Shutterstock
Transformer Technology May 2023 71

Issue 28

To ensure that all people globally have

reliable, safe and secure energy
in a sustainable world.
• Asset & Test Data Management • High Power Test Systems

• Condition Monitoring • Insulating Material Diagnostics

• Cyber Security Solutions • Partial Discharge Testing & Monitoring

• Electrical Test Instruments • Protection Testing

www.doble.com

The role of SMEs in and can look at the References

[1] https://chat.openai.com/

data analysis is data, the context [2] https://abad1dea.tumblr.com/

post/182455506350/how-

not going to go away and the details math-can-be-racist-giraffing

[3] https://www.npr.org/sections/

in the near future, simultaneously health-shots/2019/04/01/

708085617/how-can-doctors-

and we still need to come up with be-sure-a-self-taught-

computer-is-making-the-

someone who knows something ‘outside right-diagnosis?

[4] https://www.kdnuggets.

what is going on, the box’. com/2018/04/dirty-little-

secret-data-scientist.html
[5] https://hbr.org/2019/02/how-
to-choose-your-first-ai-project
[6] https://ieeexplore.ieee.org/
Conclusions: AI/ML can only work is not going to go away in the near document/9615946
on what it has been ‘shown’ and fill in future, and we still need someone [7] “Practical Machine Learning
the gaps. It is very poor at generating who knows what is going on, and can Applications”, T. Rhodes et
‘new’ knowledge. look at the data, the context and the al, ‘CIGRE Grid of the Future’,
details simultaneously to come up Providence, RI, 2021,
The role of SMEs in data analysis with something ‘outside the box’.
72 FEATURE
INTERVIEW

Seth Johnson
 Transformer Technology May 2023 73

Issue 28

Vice President
at Powerside
Ultimately, I believe
technology is always
going to get better, but
is it going to be good
enough to maintain the
stability required for
an optimal high
functioning power
system?
Interview with Seth Johnson

That's where I think our

business plays in, and
that's where we have
our play in the market.
Photo: Powerside
74 FEATURE
INTERVIEW

Alan Ross: We're at Distributech 2023. My next distributed energy resources now that are
interview was with Seth Johnson. He's a Vice contributing power to the grid. We're at a point
President at Powerside. Welcome. Thank you. in time where being able to understand what's
actually happening on the grid, how power is
Seth Johnson: Thank you for having me. being used, how it's being produced, how it's
being consumed, and how it's being stored,

AR Tell me a little bit about your career, which is so critical to the infrastructure that we

◼ We're at a point in time where being able

how you got into this industry, and have in general.
how you got to Powerside.

to understand what's actually happening on the

SJ Yeah, it's been an interesting road. I
actually never had a desire to get into the grid, how power is being used, how it's being
produced, how it's being consumed, and how

infrastructure that we have in general. ◼

Power Systems industry.
it's being stored, which is so critical to the
I studied psychology and got a degree in
psychology and business. And then my goal was
to go into neuroscience. I started a PhD program The problem essentially is that we’re
in neuroscience, worked in research for several transitioning from coal-fired power plants, high
years and decided it was not for me. I had a family inertia generation, and we're using transistor-
member who worked in the power industry. They based technology, or inverter-based technology
were a manufacturer sales rep. in Minneapolis, to essentially create this AC sine wave back
which is where I grew up, and I spent about onto the system. Doing this at small scale,
four years working for them. They hired me as a people didn't really think much of it because
technical sales rep, and I got in and just started it didn't do a whole lot, but now you're seeing
absorbing everything. I'm in the power business large amounts of it. When you think about how
now, and it's addictive. energy is being produced and consumed and
then stored, as we get into DC micro grids and

AR You're of the generation, Seth, that

wants to know that they're making a
difference. That's how we're attracting people
now, not because they're about pay and
the fact that we're a pretty secure industry.
You're making a difference. You probably use
psychology when you talk to your customers to
understand what they think or how they think
or what they do. I want to talk about Powerside,
because obviously now you're a VP. Explain
what it is that you do with the company.

SJ I'm a Vice President and General

Manager of our Corrections Business
division. At Powerside we have two different
divisions, one in Montreal and one in Alameda,
California, two different product lines. We're
the same company, but I manage everything
that happens out of the Montreal business,
which is our power corrections business. When
we find power quality issues and they need to
be corrected, that's where the equipment gets
manufactured.

AR I was the president of EPRA, the

Electric Power Reliability Alliance,
before I retired. The changes that are going on
that we're trying to adopt or adapt to in this
industry, resiliency, reliability, safety, are creating
more power quality issues. Talk about the
problem and then we're going to talk about
Powerside’s solution to it.

SJ Sure. The problem is it's an ongoing

challenge. I mean, we have all these
 Transformer Technology May 2023 75

Issue 28

energy storage the problem is that these power ◼ When you think about how energy is being
sources rely on inverter-based technology. produced and consumed and then stored, as
we get into DC micro grids and energy storage

on inverter-based technology. ◼
You're using high frequency switching to create
this sine wave to bring power onto the network, the problem is that these power sources rely
which is creating noise on the distribution grid.

Power Measurement Solutions Power Quality & Power Corrections Solutions

Quickly identify and diagnose power quality issues in equipment Reduce power factor penalties, save energy and ensure the
across your business, fleet or grid. Uncover emerging risks that efficiency of your electrical network - even in the most taxing
may not be on your radar. operating environments.
Photo: iStock, Powerside
76 FEATURE
INTERVIEW

AR It's interesting, we did some

interviews at the Re+, which is a
conference in Anaheim, and one of the things
was all induction-based motors, transformer-
based welding. Now it's inverter-based welders,
you have variable speed drives, variable
that came up was how the whole grid being frequency drives, DC drives, all of that stuff
inverter-based technology is affecting the which is controlling motors. All of that allows
assets themselves. In addition to power quality, the motor to become a little bit smarter. But
transformers are not lasting as long as they it creates another issue, which is, again, this
did because they're not used to various power harmonic content on the network.
sources, and historically only to step down
voltage, right? Not step everywhere! You can The other thing that's really interesting is high
give it, you can take it. It's kind of a mess in frequency emissions. These are high-frequency
there. The impact of power quality, let's say, on noises that are in the bandwidth of 9 to 150
the end user; whether that is; let's deal with kHz. We did a study at a plastic extrusion
residential first and then I want to talk about facility, and they had a 10 kHz voltage of
how data centers might be impacted, how around 25 volts, so it's this very, very high
industrial plants might be impacted, but what frequency voltage, which nobody can really
is the actual impact of bad or poor power pick up.
quality in a residential environment?
The good news is, in many cases, it gets

SJ When you think about it from a

residential standpoint, essentially, we're
losing inertia on the grid, which is what creates
dissipated. It typically can't flow through the
transformer back onto the grid. The downside
is that communication and control systems
the frequency tolerances in which we run the can be greatly affected. The circuit boards are
system. When you have all these PV applications frying, capacitors are blowing up in the control
that are contributing, you might have enough boards. We actually manufacture a very high-
power available, but if there's a big inrush, or a end power quality monitoring device, which
large motor load, it might not be able to sustain does waveform capture, waveform sampling.
the voltage, and it might also shift the frequency. We can do high frequency emission testing,
With the amount of inverter-based technology looking at those very high-frequency voltages,
in the modern electrical system, adding solar and then on my side of the business, we do the
increases harmonic content, which is a multiple correction. We have a power system analysis
of the fundamental frequency that is present. program where we'll go get data in the field,
This happens with any kind of high frequency and then come up with a solution. We're using
switching devices. Harmonic content is active harmonic filters, passive filters, and
dissipated as heat in the system, fundamentally. capacitor banks for power factor correction,
You think about it from your conductors inside and we'll even do high pass filters for supra
of your home to the conductors going to the harmonics, these high frequency noises that
transformer, and now you have all of this heat, pose themselves as issues in distribution grids.

◼ We actually manufacture a very high-end

and then you think, what is the long-term effect
of this? If we have, for instance, high harmonic
distortion in a residential network, which could power quality monitoring device, which does
also be the same in commercial, or industrial waveform capture, waveform sampling.
electrical network. We can do high frequency emission testing,
looking at those very high-frequency voltages,
AR the correction. ◼
In the data center market, it's and then on my side of the business, we do
absolutely imperative that they have
clean power. A lot of industrial applications
now use robotics. Robotics are impacted by
bad power quality. We hear that a lot, that the
industrial power quality issues are growing. In
AR One of the issues that everybody is
having, whether you're a supplier
to the industry or whether you are the utility
2001 EPRI did a projection by the next decade. industry, is labor. That's from everything, the
We've already passed that time. The dollar loss unskilled technician to the skilled tech, skilled
of power quality issues in industrial America was trades linemen. You have the detection and the
somewhere around $50 billion annually. It's a lot correction. How can it help the labor shortage
of money that industry is going to lose, and they or how can it help the people in the company
have to be competitive. How does Powerside work better, work smarter, work faster? In the
deal with that problem? detection, you got to be using input from the
people in the company. How are you helping

SJ You made an interesting point there.

Go back 30, 40 years, where you have
them do their jobs better?

these big induction motors, at heavy industrial

facilities doing various production process. It SJ For general industry, it's about equipment
uptime, when we get into the correction
 Transformer Technology May 2023 77

Issue 28

side of things. But we can't do that unless we That plastic extrusion facility I was telling you
can detect what the problem is. From a process about, replaces all their drives every three weeks.
perspective, our goal is certainly to improve This is millions of dollars a year! When you can
efficiency of these facilities and decrease waste. go in with a solution and say: No, this is your
When we do power factor correction, we're able issue, this is where it's at and this is how we can
to decrease current consumption and improve fix it; you're a hero in that scenario. We're not an
the efficiency of the power system, which will engineering services company, but we provide
also improve the integrity of the system long- a lot of very specific knowledge for specific
term. When we're talking about harmonics, how applications.
they might perpetuate through the electrical
system, and how they can be damaging to
AR You also mentioned something about
Photo: Powerside

electrical equipment, you could see how a lot getting the data from the equipment,
of consumers may not have the expertise to to be able to correct, and that's really a part of
understand this power quality phenomenon. our passion at APC Technologies – giving the
78 FEATURE
INTERVIEW

Photo: Powerside
Transformer Technology May 2023 79

Issue 28

operators more of an opportunity to manage of energy storage. I don't mean it's going to get
their own system, and then they don't have smaller base solely on capacity, but it's going to

◼ Essentially, this smart grid is going to be

to have a department that comes in and does become more vulnerable.
maintenance.

Lastly, but not finally because we will reach the future. For example, the utility is going to
out to you for another edition. Technology is know your car is plugged into the wall, so if
changing rapidly. The use of AI, we've kind of they need to supplement power somewhere
else, they'll have the ability pull power out of

device is connected to the grid. ◼

adopted IoT. We accept it in the utility industry.
From a standpoint of technology, what is next your vehicle, or whatever other energy storage
that we have to accept into the industry?

SJ I talked a little bit earlier about energy

being produced, consumed and stored.
Essentially, this smart grid is going to be the
Ultimately, I believe technology is always going
to get better, but is it going to be good enough to
maintain the stability required for an optimal
future. For example, the utility is going to know high functioning power system? That's where I
your car is plugged into the wall, so if they need think our business plays in, and that's where we
to supplement power somewhere else, they'll have our play in the market. I believe the smart
have the ability pull power out of your vehicle, or grid in 10, 15, 20 years is going to change the way
whatever other energy storage device is connected that we produce, consume and store energy.
to the grid. I heard from an industry expert that
the utility grid in a way is getting smaller. I said,
okay, what do you mean? They said, we're going
to get rid of all this centralized generation. It's
AR Seth, it has been a delight.

going to be all kinds of decentralized generation,

such as wind turbines, solar, and various types SJ What a pleasure.
80 SOLID STATE
TECHNOLOGY

Solid State Technology

to Streamline Global
Transition to Clean Energy
by Tajwer Khanam

• The electrical power system of a country generally consists of generators,

high voltage transmission lines that stretch hundreds of miles followed by
distribution lines that span millions of miles in order to serve a range of
consumers.
• Existing grid infrastructure employs non-ecofriendly equipment that
leads to GHG emissions followed by over voltage, phase imbalance and
harmonic pollution issues.
• Modernization of the grid will utilize the solid-state technologies that in
turn are expected to not only streamline the power system operations, but
also to assist countries in reducing their carbon footprint.
 Power Systems Technology May 2023 81

Issue 28

The electrical power system of gas and diesel generators, are not
a country generally consists of only a costly option at times, but
generators, high voltage transmission negatively impact the environment
lines that stretch hundreds of miles, as well. However, in recent years we
followed by distribution lines that have observed a substantial increase
span millions of miles in order to in the deployment of renewables in
serve a range of consumers. Along the generation mix of countries along
with generators, transmission and with the installation of battery energy
distribution lines electrical power storage projects and EV charging
system comprises of substations infrastructure that calls for the grid
Tajwer Khanam is a market analyst at PTR Inc.
as well, and they act as a critical infrastructure to have the capability
She supports custom consulting projects re-
interconnection among generation, of bidirectional flow of electricity and
lated to the power grid and is responsible for
transmission, distribution, and information. This sort of capability
data collection and analysis in various areas
consumers. that allows bidirectional flow of
including the structure of distribution utili-
power and information is absent
ties, installed base of transmission & distri-
In a conventional grid electricity is in the conventional grids, hence
bution equipment, and future market trends.
supplied with the help of conventional modernization and upgradation of
As a market analyst, she performs in-depth
power plants, for instance thermal, the grid is imperative.
analysis of different equipment markets such
as switchgear, substations, and transformers.
Tajwer has a technical background and a
master’s degree in Sustainable Energy from
the University of Glasgow.
Photo: Shutterstock, PTR Inc.

Figure 1: Uni directional power flow in a conventional grid. Source: PTR Inc.
82 SOLID STATE
TECHNOLOGY

Figure 2: Solid state converter applications within substations. Source: PTR Inc.

Solid State Technology to years with their ability to provide SSP converters enables them to be
Rescue dynamic real and reactive power used to carry out gradual upgradation
control especially with integrated of substations whenever required. For
As the countries are moving away energy storage in place followed by instance, if an equipment has failed or
from conventional generation facilitation of new grid networks, energy has become outdated in a substation,
sources that negatively impact dispatch and black start capability. it can be replaced with a SSP converter
the environment to renewable Furthermore, SSP converters have the which can later be linked with another
generation, the need for significant capability to control the voltage, phase, SSP converter in the later stages.
advancements in the substation frequency while allowing bidirectional
technologies has increased. Most of flow of power. Solid State Transformers (SST)
these requirements can be met with
the solid-state technology, especially These converters are efficient As the countries are moving away from
after the recent advancements in as they balance the use of AC conventional generation sources that
the technology, that in turn positively and DC topologies which in turn negatively impact the environment
impacts the overall reliability and reduces overall system losses. On to renewable generation, the need
stability of the power grid. the other hand, functional control, for significant advancements in
communication, protection, regulation the substation technologies has
Solid State Power (SSP) Converters along with other features that are increased. Most of these requirements
needed to maintain the reliability and can be met with the solid-state
The emergence of solid-state security of future grid are provided by technology, especially after the recent
converters have radically altered the SSP converters. It is noteworthy that advancements in the technology, that
landscape of power industry in recent the modular and scalable nature of in turn positively impacts the overall
reliability and stability of the power grid.

The emergence of solid-state converters Additionally, SSTs provide a wide

have radically altered the landscape of range of grid services for instance
reactive power compensation, power
power industry in recent years with their quality improvement, current limiting,
voltage regulation and power factor
ability to provide dynamic real and reactive correction. It is significant to note that
while regulating voltage or carrying
power control. out reactive power compensation,
 Power Systems Technology May 2023 83

Issue 28

solid state transformers do not use tap technology that has the capacity to pushed for research and development
changers, which leads to a reduction not only control the power flow, but in the solid-state circuit breaker
in the maintenance costs of the also to interrupt and clear the fault in technology.
transformers. a few microseconds. A conventional
CB, on the other hand, takes a few milli The ABB claims that their concept of
In the last few years, we have observed seconds to clear the fault. Downtime solid-state circuit breakers will define
that the average cost of battery in case of an internal fault significantly the future of energy especially when it
energy storage has reduced which has impacts the energy storage systems comes to electric transportation and
resulted in batteries being deployed and related electric grid services (for battery energy storage solutions. In
and integrated with the grid for instance frequency regulation and grid marine vessels, solid circuit breakers
frequency regulation and back up with backup). Solid state circuit breakers will reduce the downtime, as they have
the help of SSTs. SSTs also act have the capability to isolate the faulty the capability to disconnect the faulty
as power electronic interface between zone, reduce the arcing probability and zone while keeping the rest of system
MV AC, and LV AC system as shown let through energy by multiple orders in service.
in the figure below. of magnitude.
On the other hand, they have also
Furthermore, SSTs have the capability Advanced power distribution claimed that their CBs will have the
to isolate faults in a manner that technologies and architectures, for capacity to prevent all the rack fuses
upstream network faults do not instance DC microgrids, require an from blowing up, which leads to a
transfer to downstream network, improved interruption rate (faster shutdown of the entire system in case
in turn allowing continuity of services switching frequency), which has also of a fault.
to customers.

Solid State Circuit Breaker These transformers include power

In a solid-state circuit breaker,
electronics circuitry that operates at high
traditional moving parts of an frequency, which in turn provides high
electromechanical CB are replaced
with the latest semiconductor controllability and bidirectional power flow.
Photo: PTR Inc.

Figure 3: Application of solid-state technology in the distribution network. Source: PTR Inc.
84 SOLID STATE
TECHNOLOGY

Hinderance in Adoption of to be adopted widely the improved also on the higher side as compared to
New Technology functionality of the solid-state conventional circuit breakers. However,
technology is required to outweigh the the emergence of hybrid circuit
Despite the advantages of solid-state costs for each potential application, breakers that employ a combination
technology, there is still a number of but this would require significant of classical electromechanical CB
bottlenecks in the way of widespread investment and policy incentives from technology and semiconductor
adoption that needs to be catered, the regulatory bodies. switches has resolved the problem.
especially the challenges linked with
the integration and impact on power In case of solid-state circuit breakers, it Furthermore, ratings of the solid-state
system operations, maintenance, and is observed that the interruption speed equipment commercially available
existing practices. For the technology is high, but the on-state losses are also plays a significant role in the
technology adoption. If a like-for-like
in terms of rating is not available in the
For the technology to be adopted widely the market, utilities are not expected to
consider that alternative.
improved functionality of the solid-state
Looking Ahead
technology is required to outweigh the costs
for each potential application, but this would In recent years, especially after the
historic Paris Agreement in 2015,
Photo: Shutterstock

require significant investment and policy countries (largely advanced

economies) across the globe are
incentives from the regulatory bodies. aggressively pursuing the deployment
Power Systems Technology May 2023 85

Issue 28

of renewables followed by the adoption However, costs associated with the resources. Furthermore, investments
of electric vehicles to electrify the deployment of solid-state technology will also be required in the research
transportation sector. Furthermore, we will continue to play a significant and development of solid-state
have also observed that the electrical role in the decision-making process technology that ensures the availability
infrastructure has become more of utilities and TSOs especially of of a like-for-like alternative in terms
vulnerable to not only physical attacks, developing economies with limited of ratings of the equipment.
but to cyber threats as well over the
years. This consolidates the case for
expansion, as well as modernization Modernization of the grid will greatly
of the electricity grid infrastructure.
depend on the solid-state technologies that
We strongly believe that modernization
of the grid will greatly depend on the in turn are expected to not only streamline
solid-state technologies that in turn
are expected to not only streamline
the power system operations, but also will
the power system operations, but also assist countries in reducing their carbon
will assist countries in reducing their
carbon footprint. footprint.

Contact
Hassan Zaheer
Chief Commercial Officer (CCO)
+49-89-12250950
hassan@ptr.inc
 86

Chief Technology Officer

Interview with Claudia Cosoreanu for Grid Automation at GE
FEATURE
INTERVIEW

Photo: General Electric

Claudia Cosoreanu &
 Issue 28
Power Systems Technology

Claudia Blanco
May 2023

Innovation and customer

87

and Claudia Blanco partnerships officer at GE

88 FEATURE
INTERVIEW

Alan Ross: I have two exciting guests that we're not that they went away, it's the fact that they're
here at DistribuTech. One of them is Claudia, being adopted, they're being brought into the
and the other one is Claudia. And I am not industry. I have never seen the utility industry
making that up. They're from General Electric. go through as much change as it's going through
And first of all, let me start with you, Claudia. right now, which is brilliant for us. Change
means need.
Claudia, tell me a little bit about your
background in the power industry and your Another thing is that you have fewer people
time at GE. because we all have staffing issues. What are
some of the other issues that you're seeing as it
Claudia Cosoreanu: I started with GE 20 years relates to the problems, the challenges that the
ago in the power industry as an engineer. I utility industry has?
graduated mechanical engineering, but with
automation and control as the major.

I moved into product management shortly after

CC Before I get into the problems, I just
want to recap what is going on. We
have decarbonization as a target. We have
that. I got my MBA in marketing and today I goals established around the globe by different
am the CTO – the Chief Technology Officer for governments, different companies. They
Grid Automation. I also lead the Production want to be net zero in 2030, 2035. A big part
Automation and Control Product Line. of achieving that is integrating a high level of
renewable generation into the grid. The other

AR I noticed something. You wanted to

save the world when you were an
engineer, and then you got your MBA and you
trend is driving the change in transportation
and industry. You see that being pushed.

wanted to make money. We have decarbonization

as a target. We have
CC I think you need to save the world and
make money at the same time.
goals established around
AR Claudia, tell me a little bit about your
background in the power industry
and your time at GE.
the globe by different
governments, different
Claudia Blanco: I have 25 years in the industry,
but I started in automotive business, and I companies. A big part
started in the power business twelve years
ago when I joined the wind business. I was a of achieving that is
global manufacturing director to grow the wind
business onshore and offshore at that moment. integrating a high level of
Then I moved to multiple areas of advanced
technology more for a global renewable renewable generation into
business. Recently I joined Grid Solutions,
in 2018, and today I am the Innovation and the grid. Claudia Cosoreanu
customer partnerships officer. I'm an industrial
engineer, but I also did computer science. I’m So first, talking about problems worth solving,
one of those engineers that anticipate the there are more distributed energy resources
digital world will fit well with mechanical. I did integrated many times without the utilities
my MBA as well because I wanted to grow that even knowing that they're coming. And that
business. becomes difficult for the utilities because they
can't operate the grid without having visibility.
I’m one of those engineers For transmission, the renewable generation
integrated into the grid, because it is variable
that anticipate the digital and intermittent, creates grid stability issues.

world will fit well with Another problem that needs to be solved is that
due to variability and intermittency, the grid
mechanical. Claudia Blanco needs to have faster controls, so digitalization
and automation are two big problems that need

AR We all realize there's a business to

be made here. One of the things, two
years ago here at Distributech, all you saw was
to be solved. Now you need to be a lot faster with
the controls, and digitization and automation
are two big problems that need to be solved.
IoT. One year ago, all you saw was drones. It's And then there is grid resiliency. As you have
 Power Systems Technology May 2023 89

Issue 28

extreme weather events or cyber attacks, you changes, the IRA spending billions of dollars,
need to be able to recover very quickly, so that the inflation Reduction. Those are the problems
you minimize the impact on customers, and how that are exactly what you've just said. Now
many customers are impacted. what's the solution?

AR That was really good. Can you add

anything to what Claudia has just
said, Claudia?
CC There is no one solution. To comment
on what you said, I think there are
silos and ideally we would not have utilities do
different things.. But the reality is that they will.

CB Something that is very important

is to make sure we understand what
other problems are to be solved. For what
The grid will evolve depending on the specifics of
the region, of the country, of the utilities. It will
depend on the government regulations, on the
we call the grid of the future, what is now is market design. There's a lot at play here that will
happening now. To do that, as Claudia said influence the way utilities adopt some of these
before, we needed to do research, listen to our technologies. But one solution is digitization
customers, listen to the industry. That helped and automation. In order to do everything that
us identify those problems that help us we want to do with the renewable integration
prioritize and be complementary to the into the grid, while keeping the grid stable
strategy we were putting in place. We prioritize and maintaining reliability, you need to have
based on urgency and scalability, because we eyes on the grid. So you need to have as much
cannot solve a problem that is just a problem information from the grid as possible so that you
for a place, for a region, for a customer. And know at any point in time what is going on, and
collaboration is so important because we think you do that with intelligent sensors.
we are ready to collaborate and we are not,
right? Collaboration means that, to solve big The grid will evolve
problems we are going to have soon, we need
to do it in partnership. depending on the specifics
We talk to our customers and involve them of the region, of the
in selecting how to solve those problems.
The complexity of that is that if we have a country, of the utilities.
problem, we have multiple ways to solve it,
but which one is really the most efficient? It will depend on the
government regulations,
AR We already have the problem that
Photo: Shutterstock

the utilities in the United States to a

large extent cannot share information by law. on the market design.
Now we're saying to them, share information.
So we've got a lot of change going on, policy Claudia Cosoreanu
90 FEATURE
INTERVIEW

What we are talking about with some of our

customers is the next generation of a digital
substation.
CB You mentioned the drones, right? New
technologies need to also be adopted.
So how we prepare the users to adopt those new
solutions as well, we cannot miss also this piece
We call it next generation because we have been of the equation. I remember implementing
digitizing the substation for the last couple of new technologies like augmented reality some
years. The reality is that it's not adopted, not at years ago, and we tried to implement that in
the scale that we were expecting it to be. And the the factory, just to give a specific example.
reason for that is we haven't really looked at it People were not ready to use that. Those people
from an end-to-end solution point of view. It was haven’t even used an iPad before, so adoption is
just not compelling for our customers. We want going to be something to keep in mind as well,
to offer intelligent sensors as part of the solution. because this is coming now.
We want to have an integrated digital model of
the network within the reach of the substation. Another thing to add to that is how important
We want to have virtualization of some of it is to combine efforts even internally because
the functions so you have protection, control we have our digital team, we have our experts
automation in the substation, which has its own as well on the physicals, on great automation,
benefit. On top of that you can add now advanced but we also have our power conversion. Those
automation applications, such as wide area multiple areas can add their expertise and solve
protection and control or dynamic system rating. the problem. If you detect a problem, how do
you solve it with grid forming? Detection and
This is a solution that is flexible, but scalable, problem solving is something that GE brings
and you can apply it to solve multiple problems very well with the technologies we handle.
for utilities.
Detection and problem
AR One of the big problems you're going
to help solve is the people problem.
Because Larry's not sitting there anymore, he
solving is something
retired and they replaced him with a kid.JM that GE brings very well
with the technologies we
CC Absolutely right. We will we will be
able to provide a full solution, a full
technology stack. We will have the machine handle. Claudia Blanco
learning artificial intelligence technology to
help with decision making. Because you're going
to have more data, the human brain is actually
not going to be able to process it all. We need
AR How have customers you've talked to
here reacted to what you're sharing? I
love the idea of the stack, the flexibility of it, but
the technology to help. at the same time you're trying to create a whole.
 Power Systems Technology May 2023 91

Issue 28

You're not here to do pieces and parts because existing old assets? Because you're not going to
we've done pieces and parts a long time, it hasn't change all the assets overnight. And does your
worked. And the utilities are under enormous system work with the old system? I think you're
stress to adapt to all of these changes. going to find that people are going to take a
chance to be the first and then a lot of people

CC They're actually very interested. We

do have a few customers that want to
pilot the solution.
will be the first to be second.

Globally, what do you see for some of the

barriers to adoption or some of the things? You
The reality is that I believe the industry is get different geopolitical things going on. What
moving. As you were saying earlier, there do you see?
is no better time than now. The changes
are happening, I think we're seeing that in
discussions with customers. 15 years ago, it was
pretty stable. I would say static. But now you
CB For me, coming from Europe, listening
to our customers is important
worldwide because, for example, a problem of
see the interest, you see the challenge, you flexibility is not the same in Spain than as in
see the need and the willingness to try. What the US. We were talking with one of our key
we're bringing with this next generation digital customers recently, and they said, you need to
substation is the end-to-end solution, because understand that we are not ready for flexibility
we've been talking about piloting virtualization, because the regulation doesn't allow that in
the sensors, the digital twin of the network. Spain today. But by piloting this in this area, we
But when you bring it all together, it's the true can demonstrate, and here we talk about proof
value. And the reaction has been very good. of concept. Here is how we can help: piloting
early enough, giving the value, the results, and
What we're bringing with demonstrating that the value is high enough to
say that the regulation has to be adapted fast.
this next generation digital
substation is the end-to- CC I would add to that, especially in
Europe, but we've seen a couple of
cases in the United States as well, customers
end solution, because are asking us to help them put together the
business case for these new solutions and
we've been talking about to help them with their seven-year, ten-year
plan to really prove to the regulators that this
piloting virtualization, the is the way to go. And you did mention the
performance-based compensation. It is starting
sensors, the digital twin to spread. It started in California. There are
other states that are thinking about it. Europe
of the network.And the is thinking about it as well. There will be a move
towards performance-based, there's no longer
reaction has been very just the rate case.

good. Claudia Cosoreanu

CB Something very important I want to
add to that, because it's an amazing

AR You're going to be able to create this

whole end-to-end, and you're also
going to be able to have a digital version of that,
subject, is how funding from the government
can help. Here in Europe, for example, if you
want to apply for a call for a governmental
right? I love that the world is changing, and they funding support, they include you in the
will get there. collaboration in some way. For example, if
you want to work on one area of artificial
Last question I need to ask you. Some countries, intelligence, there is a call that obligates you to
some locals can say everybody will do it this work with three different countries, and there
way. We are the utility, we have the power. are areas that you have to meet such as
Not so in the United States. We have 50 states transition, distribution. This is helping to break
regulating all of the utilities. California was the silos, as we say, but it also helps regulations
one of the first to move to more performance- to enter into the picture. I think here there are
based rates, right. So as a result of that, they're a lot of things that we could do with that kind
going to say, hey, is this going to help us perform of support.
Photo: Shutterstock

better? Are we going to be able to keep the

lights on? Are we going to be able to be resilient
in the case of storms or fires or whatever? Are
we going to be reliable? Can we maintain the
AR This has been a delight. Claudia, thank
you so much, Claudia. It was brilliant.
Thank you. We appreciate it very much.
92 FEATURE
INTERVIEW

Chip Angus

Photo: SDMeyers
Transformer Technology May 2023 93

Issue 28

Reliability Account Manager

at SDMeyers
The lead times on buying
new transformers and
used transformers
has really extended.
That's really driving the
Interview with Chip Angus
market to maintain the
equipment that they have
and start implementing
these maintenance plans.
94 FEATURE
INTERVIEW

Alan Ross: Our next guest is Chip Angus. Chip is breakers, your relays,
a dear friend. Thank you so much for joining me. your cables, your
transformers, they all
Chip and I work together in the reliability have to be categorized,
world. The reliability of Transformers is kind of whether it's a one-to-
where I got my feet wet in terms of electrical four system, a mission-
systems. And it's where you got your feet wet critical system, a
because you used to be into steel before. So, system critical or a
Chip, what we're talking about is advanced noncritical system…
transformer testing and technologies. And one
of the things that you and I have been talking
about, all of the great testing and technologies
in the world only work if they give you data that
AR Talk about that. Mission critical,
systems critical. What's the difference
between those two?
you can do something with. I know you and I
have had some experience with presenting the
reliability assessment. I loved your presentation,
your discussion with them about how do you
CA Well, the mission critical designation
would actually shut down the whole
entire “mission” of a plant.
use data. So rather than talk about advanced
testing, what I want to talk about is how do you You want to put your dollars into mission critical
use the testing and the technology? assets to keep your plant running. When you
have your shutdowns in September, October,
We already have to make better data decisions whenever the plants have them, what are you
for our transformer fleet. Explain a little bit going to focus on first? You want to focus on
about that. the mission critical assets and then move down
to your system critical. The “System critical”
Chip Angus: To start off, you must have a robust, designation would shut down a system of your
CMMS system for all your electrical assets data. plant. It might be shipping and receiving, or it
If the data is not funneled into that, oftentimes might be a smelting line, something along those
within the plant, it often gets forgotten or lines. There'll be some damage there, but it's not
ignored. So that's the key to really kicking off a going to shut down the entire organization.
good, robust reliability program.
…You want to focus on
the mission critical
AR But are electrical systems in most
CMMS systems for data management,
or have they kind of been left out? They house
assets and then move
down to your system
data, but they don't make decisions on data. critical. The “System
critical” designation
would shut down
CA Yeah, I agree, Alan. They've been left
out. Historically, I think there's a move
to get them in there so they can start generating
a system of your
plant. There'll be
work orders so the upper management and some damage there,
middle management can start understanding but it's not going to
the reliability health of those electrical assets. shut down the entire
organization…
You asked me to talk a little bit about our
reliability assessment. You must have a robust
program that actually categorizes your assets
based on the criticality of each line on the
AR I get it. The point being you can
overcome it, but it's going to take time
to overcome. Even that is damaging.
plants one line drawing, so your breakers, your
relays, your cables, your transformers, they all Let’s say I have identified which are mission
have to be categorized, whether it's a one-to- critical and which are systems critical
four system, a mission-critical system, a system transformers. Give me an idea of how do I put
critical or a noncritical system. This is really the the right testing into the reliability assessment
first step in starting a reliability program. in order to make great decisions? What are the
most important tests I should run?
…You must have a
robust program that Everybody says they test their transformers,
actually categorizes but they don't. They do DGAs. It’s obviously the
your assets based on most important, but what's next?
the criticality of each
Photo: Pexels

line on the plants one

line drawing, so your CA You have your liquid screen, which
is your acid tests, your color, your
 Transformer Technology May 2023 95

Issue 28
Photo: Shutterstock
96 FEATURE
INTERVIEW
 Transformer Technology May 2023 97

Issue 28

visuals, your dielectric strength, your furan maintenance plans. Some of the things that
compounds, infrared thermography, you can do to maintain them is obviously if
ultrasound, and online DGA monitoring. you start to see acid rising in a transformer,
When you combine all those tests together you can hot-oil clean them, reduce the acids, so
with a good, robust mechanical inspection, you don't destroy the paper in the transformer.
that's going to paint a very clear picture as to Again, going back to a robust inspection, if
what's going on with your transformer. you're finding leaks on a transformer, you're
A lot of people don't realize that when labs better off to fix them rather than either taking
go to set up their Karl Fischer testing, in water, going to negative vacuum, pulling in
temperature is important. A robust mechanical moisture or atmosphere into the transformer.
inspection to assess the gauges and their We're seeing a big shift: people want to maintain
function is a must. If they're not functioning their transformers long term. That way they
properly, they're not getting a good temperature don't put themselves in a position to have to
reading from the transformer. You combine go out and find a replacement transformer,
all that, and I also recommend doing infrared because there's companies out there right
thermography at the time of your sampling. now that are suffering because they're trying
The reason is that if you get a DGA that comes to catch up on their maintenance and they're
back and you see high ethane ethylene, years behind.
maybe some high hydrogen, maybe even the
start of acetylene, IR scanning can pinpoint
where the problem is. Infrared thermography
can also detect low oil level on a transformer,
AR That's pretty much the industry as a
whole.

and temperature differences between like We are publishing this in an issue that is
bushings to name a few. It gives you an overall called Advanced Transformer Testing and
picture of what's going on with that Technologies. What I hear you say is the
transformer. technology is the data management and the
ability to put it into a CMMS. I know that
…A robust mechanical SDMyers has a very robust data management
inspection to assess system that is decision dependent. It helps
the gauges and their people make wise decisions.
function is a must…
You and I have also had experience where

AR One of the things that is critically

important, the lead time on
transformers as we speak in 2023 at the NETA
we've told people to stop, they continue to run.
And it's a $50 million loss. I love what you're
saying because it's the testing that we do, robust
conference is now going to from six months testing that we do using the technology of data
for regular power transformers to as much as management and eventually coming to the
three years. Every transformer manufacturer point where we're using not AI. We're talking
that I know of is sold out. I know that Virginia about machine learning.
transformer is just opening a new plant in
chihuahua, Mexico. They sold out the day they If I see this often enough, I can start to predict
opened for two years. seeing that engineers love extrapolation and
interpolation. We want to interpolate data to
People don't realize they can maintain their say what's happening. Give me one point, I can't
transformer. You are one of my heroes of tell you anything. Give me two, I got a straight
helping people take care of the fleet they've line. Give me three, I can tell you where things
got while they're waiting for new transformers are going. We want as many data points as
to come. We can't solve the lead time, but we we can, but the testing provides data points
can take care of what we've got in order to anyway.
extend the life of the transformer. How do
you extend the life of a transformer through Last comments. How are you doing?M
field service?

CA That's a great point. The lead times

on buying new transformers and
CA Doing fantastic.

Doing good. Busier than ever. There's a lot of

used transformers has really extended. people out there that need transformer advice
You used to, ten years ago, get a transformer and help.
Photo: Shutterstock, Pexels

in a matter of a couple of weeks. Now it's

months and maybe years, depending on
the Kva and size. So that's really driving the
market to maintain the equipment that
AR And that's what the reliability
assessment is all about. It is advice,
counsel, wise decision making. My friend, thank
they have and start implementing these you so much for joining.
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