Project Report

(Project Semester January-April 30)

Wireless Transmission of Data in Substation

Submitted by

Parinita Goel
15104074

Under the guidance of

Prof. Loveleen Kaur Govind Badhae

(Assistant Professor) (Manager)
Electrical Engineering Department SIEMENS, GURGAON

Department of Electrical Engineering

Punjab Engineering College (Deemed to be university), Chandigarh

January to April, 2018

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 DECLARATION
I hereby declare that the project work entitled ―Wireless Transmission of Data in
Substation‖ is an authentic record of my own work carried out at (Siemens) as requirements
of six months project semester of the award of degree of B.E (Electrical Engineering), Punjab
Engineering College (Deemed to be university), Chandigarh, under the guidance of Mr.
Govind Badhae and Prof. Loveleen Kaur during January to April, 2018.

Signature of student
Parinita Goel
15104074
Date:

Certified that the above statement made by the student is correct to the best of our knowledge
and belief.

Prof. Loveleen Kaur Mr. Govind Badhae

(Assistant Professor) (Senior Manager)

Electrical Engineering Department SIEMENS, GURGAON

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 ACKNOWLEDGEMENT

I would like to take this opportunity to thank both Punjab Engineering College (Deemed to
be university), Chandigarh for giving me this wonderful opportunity to undergo a semester
long internship and get a good sneak peak of the cooperate world.

I am extremely grateful to Mr. Govind Badhae (Manager), and Mr. Hamza Ehtisham (Senior
Manager), for giving me the opportunity to intern at this prestigious organization. I deem it
my privilege to have carried out this dissertation work under the organization and get a first-
hand experience of this prestigious industry.

I would like to express my sincere gratitude and indebtedness to my mentor Mr. Hamza
Ehtisham for his invaluable guidance and enormous help and encouragement, which helped
me to complete my project successfully. His way of working was a constant motivation
throughout the project term.

I acknowledge gratefully the help and suggestions of all members of the Siemens Team who
were always eager to help me with their warm attitude and technical knowledge, in spite of
their busy schedule and huge workload.

I also wish to express my appreciation and gratitude to all my colleagues at work, who were
always willing to help me with their warm attitude and knowledge that in turn helped me
integrate and settle well.

Moreover, I would like to extend my gratitude to my faculty to Prof. Tejinder Si ngh Saggu
(Head of Training, Electrical Department) and Prof. Lovleen Kaur (Faculty Coordinator),
whose constant support and regular inputs made me sail through this period of internship with
no difficulty at all.

Parinita Goel

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 TABLE OF CONTENTS
LIST OF FIGURES………………………………………………........................7

1. SUMMARY…………………………………………………..............................8
1.1 Wireless Transmission of Data………………………………………….9
2. INTRDUCTION………………………………………………………………..10
2.1 EPRI……………………………………………………………………..11
2.2 SIEMENS………………………………………………………….........11
2.3 Wireless Communication……………………………………………....12
2.4 Wireless Over Cabled System…………………………………............12
2.5 Digital Grid………………………….……………………………….....13
2.6 SICAM PAS……………………….…………………………………....13
2.7 Substation Automation System….…………………………………......13
3. WORK…………….…………………………………………………………….15
3.1 Relays
3.1.1 SIPROTEC 4……………....………………………………..16
3.1.2 SIPROTEC 5………………....……………………………..17
3.1.3 SIPROTEC COMPACT…………………………………….18
3.2 Different types of Protection…………………………………………..19
3.2.1 Over current Protection……………….……………………19
3.2.2 Distance Protection………………………………………...22
3.2.3 Differential Protection……………………….…………….27
4. INDUSTRY…………………………………………........................................33
4.1 Digital Grid……………………………………………………..….…..34
4.1.1 What Makes The Grid ―DIGITAL‖? .................................34
4.1.2 Advantages of Digital Grid…………………………….…..34
4.1.3 Giving Consumers Control…………………………....…...35
4.2 Siemens…………………………………………………………………36
4.2.1 Operations…………………………………………..………37
4.2.2 Features…………………………………………………..…44
4.2.3 Vision Statement…………………………………………...44

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 4.3 Industrial Competence………………………………………………....45
4.3.1 GE‘s Modular Substation Automation System…………….45
4.3.2 ABB: Bridging The Gap Between Analog And Digital
Technologies……………………………………………...…47
5. REVIEW ………………………………………………………………………..48
6. WORK DETAILS……………………………………………………………....50
6.1Work Programme………………………………………………………..51
6.2 Protection of Power System…………………………………………....52
6.1.1 Basic Working of Protection System……………………....52
6.1.2 Important Elements For Power System Protection………..53
6.3 Trip Circuit Supervision………………………………………....…….54
6.4 Data Communication in SAS…………………………………………..58
6.5 Standards and Protocols Used………………………………………….59
6.6 Wired Communication…………………………………………………60
6.7 Wireless Communication………………………………………………61
6.8 IEC 61850………………………………………………………………61
6.8.1 Benefit of Using IEC 61850………………………..………63
6.9 Selection of Cable……………………………………………………….63
6.10 Modes of Communication……………………………………………..64
6.10.1 Fibre Optics………………………………………………...65
6.10.2 Power Line Carrier Solutions………………………………65
6.10.3 Enterprise WI MAX/LTE…………………………..………66
6.10.4 Wireless Mesh……………………………………….……..66
6.11 Internet of Things……………………………………………………..67
6.11.1 Home Area Network……………………………………….67
6.11.2 Neighbourhood Area Network…………………………….68
6.11.3 Wide Area Network………………………………………..69
6.12 Controller Used: Node MCU………………………………….……...70
6.13 Block Diagram………………………………………………………...72
6.14 Control Centre Representation: BLYNK………………………….....73
6.14.1 Need of Blynk………………………………………………..74

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 6.14.2 Working of Blynk…………………………………………………...74
6.14.3 Features………………………………………………………74
6.14.4 Setting Blynk with NodeMcu……………………….………75
6.14.5 Setting the Blynk…………………………………..………..79
6.14.6 Circuit Diagram..…………………………………….……...82
6.14.7 Upload the Code……………………………………...……..83
6.14.8 Final Executions…………………………………….……....84
6.15 Software Simulators…………………………………………………..86
6.15.1 Autodesk Eagle…………………………………..………….87
6.15.2 Proteus……………………………………………..…….......87
6.15.3 Autodesk Circuits……………………………….…………..88
6.15.4 Fritzing……. ……………………………………..………...89
7 CONCLUSION AND FUTURE SCOPE………………………….…....…...91
7.1 Conclusion ……………………………………………………..………92
7.2 Future Scope……………………………………………………...…....92
8 IMPEDIMENTS AND SUGGESTIONS……………………………………94
8.1 Impediments………………………………………………………..…..95
8.2 Suggestions………………………………………………………….….96
8.2.1 Industry……………………………………………………..96
8.2.2 College………………………………………………………96
9 APPENDIX…………………………………………………………………....97
9.1 Algorithm ………………………………………………………………98
9.2 Actual Program…………………………………………………………99
10 REFERENCES…………………………………………………………….....105

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 LIST OF FIGURES
Figure 1 Substation Automation System ........................................................................ 14
Figure 2 SIPROTEC 4 .................................................................................................... 17
Figure 3 SIPROTEC 5 .................................................................................................... 18
Figure 4 SIPROTEC Compact ........................................................................................ 19
Figure 5 SIPROTEC 7SJ................................................................................................. 21
Figure 6 Distance Protection ........................................................................................... 23
Figure 7 SIPROTEC 7SA ............................................................................................... 24
Figure 8 SIPROTECC 7SA Rear View .......................................................................... 25
Figure 9 SIPROTEC 7SA Rear View Wiring ................................................................. 26
Figure 10 Differential Protection .................................................................................... 28
Figure 11 SIPROTEC 7SD ............................................................................................. 29
Figure 12 Differential Protection of Transformer ........................................................... 31
Figure 13 SIEMENS VISION......................................................................................... 45
Figure 14 Modular Automation System.......................................................................... 47
Figure 15 Basic Protection System ................................................................................. 52
Figure 16 Trip Supervision -CB is closed ....................................................................... 55
Figure 17 Auxillary contact completes circuit ................................................................ 56
Figure 18 Trip Supervision: remote signal required ....................................................... 57
Figure 19 Power flows: Subsystem; Inforamtion flows: Networks ................................ 69
Figure 20 NodeMCU Pin Diagram ................................................................................. 71
Figure 21 Blynk .............................................................................................................. 73
Figure 22 Setting Blynk .................................................................................................. 76
Figure 23 Inserting the libraries ...................................................................................... 77
Figure 24 Selection of Board .......................................................................................... 78
Figure 25 Create new Project .......................................................................................... 79
Figure 26 Mail the Auth Token...................................................................................... 80
Figure 27 Select the components ................................................................................... 81
Figure 28 Upload the code .............................................................................................. 84
Figure 29 Final Circuit .................................................................................................... 85
Figure 30 HMI: Control Centre ...................................................................................... 86

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CHAPTER 1
SUMMARY

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1. SUMMARY
This report is a brief description of the work done during the course of my internship at
th
SIEMENS Ltd, India (Gurgaon) during the period 4 th January, 2018 to 30 April, 2018. I

worked in the Energy Management division (Business Unit: Digital Grid) for the project
aimed at implementation of Wireless Transmission of Data.

Being a well established company, SIEMENS offered me a wide range of departments to hone
my skills in, and below lies the summary of the contributions I made as an intern to the
departments of Energy Management.

1.1 WIRELESS TRANSMISSION OF DATA

As with all smart grid applications, two-way communication is foundational to substation

automation. To enable monitoring and control, substation computers, and computers in utility
operations centres, must exchange information with intelligent electronic devices (IEDs)
throughout the substation yard. Till date the circuit breakers have not been smart and
intelligenet but as the technology advances, communication shall be made wireless between
the protection devices and will not be limited to that between the relay and control centre.

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CHAPTER 2

INTRODUCTION

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2. INTRODUCTION

2.1 EPRI (ELECTRIC POWER R-RESEARCH INSTITUTE), DEC 2002

EPRI had been working with member utilities to improve the cost benefit ratio for on -line
monitoring and diagnostics in transmission substation applications. Wireless RF sensors and
communications are on the list of candidate technologies offering the potential for cost
savings by circumventing the need for traditional cabling. Avoided cable installation saves
utilities the associated costs of meeting environmental requirements and conducting testing
required prior to installation of new cables in existing substations. Investigators developed a
specification for a wireless system. They next tested new RF sensors and communications
devices with built-in networking capabilities in monitoring applications developed
specifically for transmission substations. In this case, they selected a monitoring system for
circuit breakers in a 345-kV transmission substation owned by Consolidated Edison Company
of New York (ConEd) as a test application. They also developed a universal transmitter and
made a general comparison of several wireless technologies .

2.2 SIEMENS, JAN 2018

MindSphere is the cloud based open IoT operating system from Siemens that connects the
products and systems enabling to harness the width of data presented by the Internet of Things
(IoT) with advanced analytics.

MindSphere delivers a wide range of device and enterprise application connectivity protocol
options, industry applications, advanced analytics and an innovative development
environment that utilizes both Siemens‘ open Platform-as-a-Service (PaaS) capabilities along
with access to AWS cloud services.

Through these capabilities, MindSphere connects real things to the digital world and provides
powerful industry applications and digital services to help drive business success.

Mind Sphere‘s open PaaS capabilities enable a rich partner ecosystem to develop and deliver
industry applications, profit from the experience and insights of our partners and no
development required on customer‘s part to advance IoT strategy.

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Siemens provides business focused solutions to help drive closed loop innovation through
digital twins for products, production and performance .

2.3 WIRELESS COMMUNICATION

Wireless Communication, is the transfer of information or power between two or more points
that are not connected by an electrical conductor. The most common wireless technologies
use radio waves. With radio waves distances can be short, such as a few meters
for Bluetooth or as far as millions of kilometres for deep-space radio communications.

Wireless operations permit services, such as long-range communications, that are impossible
or impractical to implement with the use of wires. The term is commonly used in
the telecommunications industry to refer to telecommunications systems (e.g. radio
transmitters and receivers, remote controls, etc.) which use some form of energy (e.g. radio
waves, acoustic energy,) to transfer information without the use of wires. Information is
transferred in this manner over both short and long distances

2.4 WIRELESS OVER CABLED SYSTEM

The reliable management of power supply systems and its development has witnessed a rapid
growth in the demand for communications.

The following list indicates some basic advantages of using a wireless system over a cabled
system in substation applications:

• Cheaper than (often-expensive) cabling version

• More relaxed constraint on isolation level and clearances

• Portability/mobility

• Reduced susceptibility to unstable grounds

• Convenience and ease of installation

• Easier implementation of higher Insulation Protection (IP) of instruments

• Extend range and flexibility of data acquisition and I/O (configurations and locations).

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2.5 DIGITAL GRID

Smart Grid facilitates efficient and reliable end-to-end intelligent two-way delivery system
from source to sink through integration of renewable energy sources, smart transmission and
distribution. In this way Smart Grid technology shall bring efficiency and sustainability in
meeting the growing electricity demand with reliability and best of the quality.

Smart Grid also enables real time monitoring and control of power system as well as helps in
reduction of AT&C losses, demand response and demand side management, power quality
management, outage management, smart home energy system etc. Smart Grid will act as a
backbone infrastructure to enable new business models like smart city, electric vehicles, s mart
communities apart from more resilient and efficient energy system and tariff structures.
Recognizing the importance, various firms have taken pioneering steps in bringing Smart Grid
technology to all facets of power supply value chain.

2.6 SICAM PAS

SICAM PAS (Power Automation System) meets all the demands placed on a distributed
substation control system – both now and in the future. Amongst many other standardized
communication protocols, SICAM PAS particularly supports the IEC 61850 standard for
communication between substations and IEDs. SICAM PAS is an open system and – in
addition to standardized data Transfer processes – it Features user interfaces for the
integration of system-specific tasks and offers multiple automation options. SICAM PAS can
thus be easily included in existing systems and used for system integration, too.

2.7 SUBSTATION AUTOMATION SYSTEM

The substation is the node in the electrical power network. Funct ions of substation are control
and monitoring of the switch yard, recording, protection of the power equipment, revenue
metering and automation functions for energy management and assert management.
Conventional substation is composed with interlocking logic, RTU (Remote Terminal Unit),
Relays, conventional switchgear and CT/PT (current/potential transformers). Each component
is hardwired connected with parallel Cu wires.

Modern substation automation is structured in three basic levels. The station level provides an
overview across the whole station and is located in a shielded control room. Station level

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includes HMI Workstation, Master Station Computer, Backup Station Computer and GPS
(Global Positioning System) receiver, etc. The bay level conducts maintenance work only
within one bay and it is usually close to the switchgear. Bay level includes protection and
control IEDs (intelligent electrical devices) of different bays such as circuit breakers,
transformers, and capacitor banks. Equipment in bay level and station level are called
secondary equipment. Process level provides the interface between the substation automation
system and the switchgear. Process level includes switchyard equipment (also primary
equipment) such as CTs/PTs, remote I/O, actuators, merging units etc.

Figure 1 Substation Automation System

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CHAPTER 3
WORK

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3. WORK
3.1 RELAYS

3.1.1 SIPROTEC 4:

SIPROTEC 4 leads the way in integrating protection, control, measurement, and automation
functions in one device. The homogenous system platform, the unique DIGSI 4 engineering
program and extensive experience of more than a million successfully operating devices in the
field worldwide – thanks to these unique advantages, SIPROTEC 4 enjoys top recognition
among users worldwide. SIPROTEC 4 is the industry standard for digital protection
technology today in all fields of application.

SIPROTEC 4 is a milestone in protection systems. The SIPROTEC 4 device series

implements the integration of protection, control, measuring and automation functions
optimally in one device. In many fields of application, all tasks of the secondary systems can
be performed with one single device. The open and future-proof concept of SIPROTEC 4 has
been ensured for the entire device series with the implementation of IEC 61850.

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 Figure 2 SIPROTEC 4

3.1.2 SIPROTEC 5:

SIPROTEC 5 is part of the new generation of incomparable modular, flexible, and intelligent
digital field devices. With modularly designed hardware and software and its high-
performance DIGSI 5 engineering tool, the SIPROTEC 5 product family of field devices are
perfect for protection, control, monitoring, and measuring applications in electrical energy
systems. SIPROTEC 5 offers a wide product range with modular elements for every
application and requirement.

The new benchmark for protection, automation and monitoring The SIPROTEC 5 series is
based on the long field experience of the SIPROTEC device series, and has been especially
designed for the new requirements of modern high-voltage systems. For this purpose,
SIPROTEC 5 is equipped with extensive functionalities and device types. With the holistic
and consistent engineering tool DIGSI 5, a

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solution has also been provided for the increasingly complex processes, from the design via
the engineering phase up to the test and operation phase. The functionality of the device types
can be tailored to the requested application and adjusted to the ever changing requirements
throughout the entire lifecycle. In addition to the reliable and selective protection and the
complete automation function, SIPROTEC 5 offers an extensive database for operation and
monitoring of modern power supply systems.

Figure 3 SIPROTEC 5

3.1.3 SIPROTEC Compact – Maximum protection-minimum space

It provides perfect protection, smallest space reliable and flexible protection for energy
distribution and industrial systems with minimum space requirements. The devices of the
SIPROTEC Compact family offer an extensive variety of functions in a compact and thus
space-saving ¹⁄₆ x 19" housing. The devices can be used as main protection in medium-voltage
applications or as back-up protection in high-voltage systems.

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SIPROTEC Compact provides suitable devices for many applications in energy distribution,
such as the protection of feeders, lines or motors. Moreover, it also performs tasks such as
system decoupling, load shedding, load restoration, as well as voltage and frequency
protection.

Figure 4 SIPROTEC Compact

3.2 DIFFERENT TYPES OF PROTECTION:

3.2.1 OVERCURRENT:

An over current exists when current exceeds the rating of conductors or equipment. It can
result from overload, short circuit, or ground fault.

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 An overload is a condition in which equipment or conductors carry current exceeding their
rated capacity. An example is plugging two 12.5A (1,500W) hair dryers into a 20A branch
circuit.

 A short circuit is the unintentional electrical connection between any two normally current -
carrying conductors of a circuit (line-to-line or line-to-neutral).

 A ground fault is an unintentional, electrically conducting connection between an ungrounded

conductor of a circuit and the equipment grounding conductor, metallic enclosures, metallic
raceways, metallic equipment, or earth. During a ground fault, dangerous voltages and
abnormally large currents exist.

SIPROTEC 7SJ6 Series

The SIPROTEC 7SJ6 series relays can be used for line protection of high and medium voltage
networks with earthed (grounded), low-resistance grounded, isolated or compensated neutral
point. When protecting motors, the SIPROTEC 7SJ6 is suitable for asynchronous machines of
all sizes. The relay performs all functions of backup protection supplementary to transformer
differential protection. The relay provides control of the circuit -breaker, further switching
devices and automation functions. The integrated programmable logic (CFC) al lows the user
to implement their own functions, e. g. for the automation of switchgear (interlocking). The
user is also allowed to generate user-defined indications. The flexible communication
interfaces are open for modern communication architectures with control systems.

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 Figure 5 SIPROTEC 7SJ

OVERVIEW OF THE FUNCTIONS

1. Protection functions

• Over current protection (definite-time/inverse-time/user-def.)

• Sensitive ground-fault detection / intermittent ground-fault protection

• High-impedance restricted ground fault

• Inrush-current detection

• Overload protection

• Temperature monitoring

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• Breaker failure protection

• Negative-sequence protection

2. Control functions/programmable logic

• Commands for control of a circuit-breaker and of isolators

• Position of switching elements is shown on the graphic display

• Control via keyboard, binary inputs, DIGSI 4 or SCADA system

• User-defined logic with CFC (e.g. interlocking)

3. Monitoring functions

• Circuit-breaker wear monitoring

• Slave pointer

• Time metering of operating hours

• Trip circuit supervision

• Motor statistics

APPLICATION

The SIPROTEC 7SJ6 unit is a numerical protection relay that also performs control and
monitoring functions and therefore supports the user in cost-effective power system
management, and ensures reliable supply of electric power to the customers. Local operation
has been designed according to ergonomic criteria. A large, easy-to-read display was a major
design aim.

3.2.2 DISTANCE PROTECTION

Since the impedance of a transmission line is proportional to its length, for distance
measurement it is appropriate to use a relay capable of measuring the impedance of a line up
to a predetermined point (the reach point).Such a relay is described as a distance relay and

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 is designed to operate only for faults occurring between the relay location and the selected
reach point, thus giving discrimination for faults that may occur in different line sections.

Figure 6 Distance Protection

The basic principle of distance protection involves the division of the voltage at the relaying
point by the measured current. The apparent impedance so calculated is compared with the
reach point impedance. If the measured impedance is less than the reach point impedance, it is
assumed that a fault exists on the line between the relay and the reach point.

The reach point of a relay is the point along the line impedance locus that is intersected by the
boundary characteristic of the relay.

Since this is dependent on the ratio of voltage and current and the phase angle between them, it
may be plotted on an R/X diagram. The loci of power system impedances as seen by the relay
during faults, power swings and load variations may be plotted on the same diagram and in this
manner the performance of the relay in the presence of system faults and disturbances may be
studied.

SIPROTEC 7SA SERIES

The 7SA522 relay provides full-scheme distance protection and incorporates all functions
usually required for the protection of a power line. The relay is designed to provide fast and

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selective fault clearance on transmission and sub transmission cables and overhead lines with
or without series capacitor compensation. This contributes towards improved stability and
availability of your electrical power transmission system. The power system star point can be
solid or impedance grounded (earthed), resonant-grounded via Peterson coil or isolated. The
7SA522 is suitable for single and three-pole tripping applications .‘The effect of apparent
impedances in unfaulted fault loops is eliminated by a sophisticated and improved method
which uses pattern recognition with symmetrical components and load compensation. The
correct phase selection is essential for selective tripping and reliable fault location. During
network power swings, an improved power swing blocking feature prevents the distance
protection from unwanted tripping and optionally provides controlled tripping in the event of
loss of synchronism (out of step). This function guarantees power transmission even under
critical network operating conditions.

Figure 7 SIPROTEC 7SA

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 Figure 8 SIPROTECC 7SA Rear View

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 Figure 9 SIPROTEC 7SA Rear View Wiring

OVERVIEW OF THE FUNCTIONS

1. Over voltage protection, under voltage protection

The 7SA6 contains a number of overvoltage measuring elements. Each measuring element is
of two-stage design. The following measuring elements are available:

• Phase-to-ground overvoltage

• Phase-to-phase overvoltage

• Zero-sequence overvoltage

• Positive-sequence overvoltage of the local end or calculated for the remote end of the line
(compounding)

• Phase-to-ground under voltage

• Phase-to-phase under voltage

• Positive-sequence under voltage

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2. Frequency protection

Frequency protection can be used for over frequency and under frequency protection.
Unwanted frequency changes in the network can be detected and the load can be removed at a
specified frequency setting. Frequency protection can be used over a wide frequency range
(45 to 55, 55 to 65 Hz). There are four elements (selectable as over frequency or under
frequency) and each element can be delayed separately.

APPLICATION

The 7SA522 relay provides full-scheme distance protection and incorporates all functions
usually required for the protection of a power line. The relay is designed to provide fast and
selective fault clearance on transmission and sub transmission cables and overhead lines with
or without series capacitor compensation. This contributes towards improved stability and
availability of your electrical power transmission system. The power system star point can be
solid or impedance

grounded (earthed), resonant-grounded via Peterson coil or isolated. The 7SA522 is suitable
for single and three-pole tripping applications with and without tele (pilot) protection
schemes.

3.2.3 DIFFERENTIAL PROTECTION

Differential relay is the most important and widely used for the protection of Transformers,
generator-Transformer unit, Bus Bars, Feeders and heavy Motors etc in electrical power
system the ANSI code of Differential relay is87.
As the name shows Differential mean it works on the principle of comparison between two
quantities, which checks every time the phase difference between incoming quantity and
outgoing quantity if difference between these two quantities exceeds the phase difference of
relay pick up level then the Differential relay will operate to protect the unit and Differential
relay isolate the unit from the faulty zone.

A differential relay is defined as the relay that operates when the phase difference of two or
more identical electrical quantities exceeds a predetermined amount. The differential relay
works on the principle of comparison between the phase angle and magn itude of two or more

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similar electrical quantities. Comparing two electrical quantities in a circuit using differential
relays is simple in application and positive in action.

Figure 10 Differential Protection

For the operation of the differential relay, it should have two or more electrical quantities, and
these quantities should have a phase displacement (normally approximately 180). Any types
of the relay can operate as a differential relay depends on upon the way it is connected in a
circuit. In other words, it doesn‘t depend on the construction of the relay it depends on the
way it is connected to the circuit.

SIPROTEC 7SD SERIES (LINE DIFFERENTIAL)

The 7SD52/53 relay provides full scheme differential protection and incorporates all functions
usually required for the protection of power lines. It is designed for all power and distribution
levels and protects lines with two up to six line ends. The relay is designed to provide high-
speed and phase-selective fault clearance. The relay uses fibre-optic cables or digital
communication networks to exchange telegrams and includes special features for the use in

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multiplexed communication networks. Also pilot wires connections can be used with an
external converter. This contributes toward improved reliability and availability of the
electrical power system.

Figure 11 SIPROTEC 7SD

The relay is suitable for single and three-phase tripping applications for two up to six line
ends. Also, transformers and compensation coils within the differential protection zone are
protected as are serial and parallel-compensated lines and cables. The relays may be employed
with any type of system earthing. The relay also provides a full-scheme and non-switched
distance protection as an optional main 2 protection. Several tele-protection schemes ensure
maximum selectivity and high-speed tripping time.

OVERVIEW OF THE FUNCTIONS

1. Protection functions

• Differential protection with phase segregated measurement

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• Restricted earth-fault protection transformers within the protection zone

• Non-switched distance protection with 6 measuring systems

• High resistance ground (earth)-fault protection for single and three-pole tripping

• Phase-selective inter tripping

• Tele (pilot) protection

• Fault locator (FL)

2. Control functions

• Commands control of CB and isolators

Monitoring functions

• Self-super vision of relay and protection data communication

• Trip circuit supervision

APPLICATION

SIPROTEC 7SD52/53 is a full-scheme differential protection relay for two up to six line ends,
incorporating all the additional functions for protection of overhead lines and cables at all
voltage levels. Also transformers and compensation coils within the protection zone are
protected. The 7SD52/53 is suitable for single-pole and three-pole tripping. The power system
star point can be solid or impedance-grounded (earthed), resonant-earthed via Peterson coil or
isolated.

SIPROTEC 7UT SERIES (TRANSFORMER DIFFERENTIAL)

The SIPROTEC 7UT6 differential protection relays are used for fast and selective fault
clearing of short-circuits in transformers of all voltage levels and also in rotating electric
machines like motors and generators, for short lines and bus bars.

The protection relay can be parameterized for use with three-phase and single-phase
transformers.

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The specific application can be chosen by parameterization. In this way an optimal adaptation
of the relay to the protected object can be achieved.

Figure 12 Differential Protection of Transformer

In addition to the differential function, a backup over current protection for 1 winding/star
point is integrated in the relay. Optionally, a low or high-impedance restricted earth-fault
protection, a negative sequence protection and a breaker failure protection can be used.
7UT613 and 7UT633 feature 4 voltage inputs. With this option an overvoltage and under
voltage protection is available as well as frequency protection, reverse / forward power
protection, fuse failure monitor and over excitation protection. With external temperature
monitoring boxes (thermo-boxes) temperatures can be measured and monitored in the relay.
Therefore, complete thermal monitoring of a transformer is possible, e.g. hot -spot calculation
of the oil temperature.

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OVERVIEW OF FUNCTION

1. PROTECTION FUNCTIONS

• Differential protectionfor2-upto 5-winding transformers (3-/1-phase)

• Differential protection for motors and generators

• Differentialprotectionforshort2upto 5terminallines

• Differential protection for bus bars up to12feeders

• Differential protection with phase-segregated measurement

• Sensitive measuring for low-fault currents

• Fast tripping for high-fault currents

• Phase/earth over current protection

• Overload protection with or without temperature measurement

• Negative-sequence protection

• Breaker failure protection

• Low/high-impedance restricted earth fault (REF)

• Voltage protection functions

2. CONTROL FUNCTIONS

• Commands for control of circuit breakers and isolators

• Self-super vision of the relay

• Trip circuit supervision

• Oscillo graphic fault recording

• Permanent differential and restraint current measurement, extensive scope of operational

values

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CHAPTER 4

INDUSTRY

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4. INDUSTRY
4.1 DIGITAL GRID
The grid," refers to the electric grid, a network of transmission lines, substations, transformers
and more that deliver electricity from the power plant to your home or business. Our current
electric grid was built in the 1890s and improved upon as technology advanced through each
decade. Today, it consists of more than 9,200 electric generating units with more than 1
million megawatts of generating capacity connected to more than 300,000 miles of
transmission lines. Although the electric grid is considered an engineering marv el, we are
stretching its patchwork nature to its capacity. To move forward, we need a new kind of
electric grid, one that is built from the bottom up to handle the groundswell of digital and
computerized equipment and technology dependent on it.

4.1.1 WHAT MAKES THE GRID “DIGITAL”?

The digital technology that allows for two-way communication between the utility and its
customers, and the sensing along the transmission lines is what makes the grid smart. Like the
Internet, the Smart Grid will consist of controls, computers, automation, and new technologies
and equipment working together, but in this case, these technologies will work with the
electrical grid to respond digitally to our quickly changing electric demand.

4.1.2 ADVANTAGES OF DIGITAL GRID

The benefits associated with the Smart Grid or the digital grids include:

 More efficient transmission of electricity

 Quicker restoration of electricity after power disturbances

 Reduced operations and management costs for utilities, and ultimately lower power c osts
for consumers

 Reduced peak demand, which will also help lower electricity rates

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 Increased integration of large-scale renewable energy systems

 Better integration of customer-owner power generation systems, including renewable

energy systems

 Improved security

Today, an electricity disruption such as a blackout can have a domino effect —a series of
failures that can affect banking, communications, traffic, and security. This is a particular
threat in the winter, when homeowners can be left without heat. A smarter grid will add
resiliency to our electric power System and make it better prepared to address emergencies
such as severe storms, earthquakes, large solar flares, and terrorist attacks. Because of its two -
way interactive capacity, the Smart Grid will allow for automatic rerouting when equipment
fails or outages occur. This will minimize outages and minimize the effects when they do
happen. When a power outage occurs, Smart Grid technologies will detect and isolate the
outages, containing them before they become large-scale blackouts. The new technologies
will also help ensure that electricity recovery resumes quickly and strategically after
emergency — routing electricity to emergency services first, for example. In addition, the
Smart Grid will take greater advantage of customer-owned power generators to produce
power when it is not available from utilities. By combining these "distributed generation"
resources, a community could keep its health centre, police department, traffic lights, phone
System, and grocery store operating during emergencies. In addition, the Smart Grid is a way
to address an aging energy infrastructure that needs to be upgraded or replaced. It‘s a way to
address energy efficiency, to bring increased awareness to consumers about the connection
between electricity use and the environment. And it‘s a way to bring increased national
security to our energy System—drawing on greater amounts of home-grown electricity that is
more resistant to natural disasters and attack.

4.1.3 GIVING CONSUMERS CONTROL

The Smart Grid is not just about utilities and technologies; it is about giving you the
information and tools you need to make choices about your energy use. If you already manage

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activities such as personal banking from your home computer, imagine managing your
electricity in a similar way. A smarter grid will enable an unprecedented level of consumer
participation. For example, you will no longer

have to wait for your monthly statement to know how much electricity you use. With a
smarter grid, you can have a clear and timely picture of it. "Smart meters," and other
mechanisms, will allow you to see how much electricity you use, when you use it, and its
cost. Combined with real-time pricing, this will allow you to save money by using less power
when electricity is most expensive. While the potential benefits of the Smart Grid are usually
discussed in terms of economics, national security, and renewable energy goals, the Smart
Grid has the potential to help you save money by helping you to manage your electricity use
and choose the best times to purchase electricity. And you can save even more by generating
your own power .

4.2 SIEMENS

Siemens is a Conglomerate company that was founded by Wernervon Siemens and Johann
George Halske on October 12, 1847 and is headquartered in Munich, Germany. Josef Kaeser
is the CEO of the global organization that has operations in around 200 countries and
approximately 285 production and manufacturing facilities. Siemens' long-term commitment
in India began in 1867, when Werner von Siemens personally supervised the setting up of the
first telegraph line between London and Calcutta.

Siemens India is a leader in technology solutions for intelligent(smart),susta inable cities,

smart grid, Building technologies, Mobility, Energy Management, Power and Gas, Intelligent
Infrastructure, Industrial Applications, Healthcare, Smart Financing and power distribution.
Siemens is already involved in the Restructured Accelerated Power Development and
Reforms Programme of the Government of India for installing Smart Grid solutions in
multiple cities in India.

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 4.2.1 OPERATIONS
Electrification, automation and digitalization are the long-term growth fields of Siemens. In order to
take full advantage of the market potential in these fields, our businesses are bundled into eight
divisions and Siemens Healthineers as well as Siemens Wind Power as a separately managed
business.

 BUILDING TECHNOLOGIES:
Building Technologies is the world market leader for safe, energy efficient and
environmentally friendly buildings and infrastructure. As a technology partner, consultant,
service provider, system integrator and product supplier, Building Technologies offers fire
protection, security, building automation, heating, ventilation and air conditioning (HVAC)
and energy management products and services.
The Building Technologies Division offers:
A comprehensive portfolio of components, products and systems for demand-based, efficient
control of heating, ventilation and air conditioning (HVAC) plants, with all components optimally
matched and covering all technical applications in the HVAC sector.

 Consulting and services as well as products and technologies aimed at optimizing the
performance, comfort and energy efficiency of buildings and infrastructures across their ent ire
lifecycle.
 Comprehensive monitoring, maintenance, modernization and efficiency optimization services
for buildings and infrastructures.
 Comprehensive consulting services for energy management, energy procurement and
consumption analysis, and implementation of efficiency measures.
 Innovative, high-quality fire safety products, systems and solutions for early and reliable
detection, quick and deception-proof alarming and evacuation processes as well as intelligent
extinguishing based on current room conditions.
 Planning, design, setup, maintenance, monitoring, financing and operation of integrated
security solutions, including command and control systems, security management systems,
and intelligent video analysis systems.

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 Integrated systems and solutions for specific markets and industries such as data centres,
utility companies, airports, hospitals and hotels.
 Consulting, planning, development and financing of turnkey integrated automation, security
and fire safety solutions for buildings and infrastructures (Total Building Solutions, TBS).

 DIGITAL FACTORY:
The Digital Factory Division offers a comprehensive portfolio of seamlessly
integrated hardware, software and technology based services in order to support
manufacturing companies worldwide in enhancing the flexibility and efficiency of their
manufacturing processes and reducing the time to market of their products.
The seamless integration of data along the industrial value chains will gain more and
more in importance, becoming a key criterion for the survival of developing / manufacturing
companies. The Digital Factory Division aims to provide its customers with a comprehensive
portfolio of hardware and software products which enable the comprehensive integration of data
from development, production and suppliers. The complete digital representation of the entire
physical value chain is our ultimate goal. We call the solution platform which we created for this
purpose "Digital Enterprise".

 ENERGY MANAGEMENT:
The Energy Management Division is one of the leading global suppliers of products, systems,
solutions and services for the economical reliable and intelligent transmission and distribution
of electrical power. The portfolio includes facilities and systems for the low voltage and
distribution power grid level, smart grid solutions and high voltage transmission systems.
Energy storage systems and solutions for decentralized energy systems complete the offer.

The steady increase of distributed energy systems, the integration of renewable energy sources and
aging grid infrastructures can prevent the safe and reliable supply of power. Power producers, grid
operators, power utilities, industrial companies, and municipalities can manage tasks economically
and in the best way possible despite increasing complexity, by leveraging the extensive Siemens
portfolio of technologies, products, services, and solutions.

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 FINANCIAL SERVICES:
The Financial Services Division (SFS) provides business to business financial solutions.
Around the globe, Siemens supports customer investments with project and structured
financing as well as leasing and equipment finance. Aligning with the growth fields of
electrification, automation and digitalization, the company supports
customer investments with leasing solutions and equipment, project and structured financing. It
provides capital for Siemens customers as well as external businesses and serves as an expert
adviser for financial risks within Siemens. The financial and industry know-how creates customer
value and enhances customer competitiveness while building trust in new technologies and
facilitating their market launch.

 MOBILITY:
Efficient and integrated transportation of people and goods by rail and road - all products,
solutions and services regarding mobility are handled by the Mobility Division.

The demand for mobility is growing all over the world. Transporting people and goods to all
corners of the earth presents challenges for the infrastructure of national economies. This applies, in
particular, to the transport and logistics facilities of cities: Will cities be able to solve the problems
caused by increasing road traffic? Can public transportation help them avoid total gridlock? How
can railway operators increase the efficiency and safety of their systems? How can rail and road
traffic be integrated? How can logistics supply chains be further optimised as freight volumes
continue to increase steadily?

The Mobility Division provides answers to all of these questions with its comprehensive portfolio;
because modern, interconnected and IT-based mobility is the core competency of its five business
units: Mobility Management, Turnkey Projects & Electrification, Mainline Transport, Urban
Transport and Customer Services. They have the know-how to make road traffic flow more
smoothly and quickly, make trains more environmentally friendly and efficient, make train
schedules and freight shipments more reliable. We work with our customers to develop optimal
solutions to help overcome their challenges.

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 The portfolio of the Mobility Division includes

 the full range of vehicles for rail traffic: Regional, as well as intercity and high speed trains, metro
cars, streetcars and light rail, passenger coaches, driverless vehicles and locomotives
 Signal and control technology for rail-based passenger and freight traffic
 Electrification solutions for rail and road traffic
 Maintenance and service of vehicles and infrastructure
 Road traffic control and information systems, parking space management as well as electronic
payment and toll systems for urban and interurban traffic
 Consulting, planning, financing, construction and operation of turnkey mobility systems
 Integrated mobility solutions for intermodal networking of different traffic systems

 POWER AND GAS:

The Power and Gas Division is the trusted partner for world class products and solutions for
the oil and gas, power and industrial markets. The division is dedicated to deliver its
customers reliable, efficient, clean and safe products and solutions.
The Power and Gas Division offers utilities, independent power producers, engineering,
procurement and construction companies (EPCs), and oil and gas customers a broad spectrum of
products and solutions for the environmentally-compatible and resource-saving generation of power
from fossil fuels and renewable sources of energy and for the reliable transportation of oil and gas.
The portfolio is perfectly matched to the challenges of a dynamic market and includes the
following:

 Gas turbines with capacities ranging from five to 400 MW. Our gas turbines offer high efficiency,
reliability, and environmental sustainability, qualities that in turn deliver low lifecycle costs and
make power plants highly profitable.
 Steam turbines in the performance range from 45 kW to 1,900 MW with a long tradition in
manufacturing process and as ongoing development.
 Generators in the power range from 25 to 2,235 MVA. Our expertise is based on more than 100
years of experience in the development and production of generators on an installed fleet of more
than 3,500 machines.

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From decentralized industrial applications to heavy duty power plants – we deliver tailored OEM
power plant solutions, focusing on your overall business success by increasing turnover, reducing
costs and improving profitability. Whatever your challenge is, we are with you from the start with
the most complex portfolio to cover your needs from Instrumentation & Controls components to
power trains up to full turnkey solutions.

 POWER GENERATION SERVICES:

With a broad spectrum of innovative products and services, Siemens is one of the leading
service partners for ensuring high reliability and optimal performance of rotating power
equipment within the utility, oil and gas and industrial processing industries worldwide.

In addition to factory- and field-based services, Siemens also has extensive experience with remote
monitoring and diagnostics. Our experts can detect even the smallest indicator that something may
not be operating normally and follow up by recommending proactive solutions before the issue
becomes serious. Furthermore, Siemens can analyze the data collected to draw trends on individual
turbines as well as the overall fleet. The results contribute to enhanced turbine performance over the
long term, thereby lowering the cost of energy.

We also continually look for ways to increase the performance of our customers‘ operating plants in
a market being driven primarily by an aging power plant fleet and the rising demand for increasing
the efficiency of existing plants in order to combat climate change, conserve natural resources and
meet the ever-growing need of an expanding global population. We will do this through life
extensions and other advanced technologies to increase the efficiency and capacity of existing
power plants, enabling them to generate substantially more electricity with the same amount of fuel.
Such solutions pay off – economically and environmentally.

 PROCESS INDUSTRIES and DRIVES:

Measurably increase the productivity and improve the time to market – with
innovative, integrated technology across the entire lifecycle. It supports in continuously

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improving the reliability , safety and efficiency of product , processes and plants. We can help
you measurably increase your productivity and improve your time to market – with innovative, integrated
technology across the entire lifecycle.

Around the world, we provide future-proof automation, drive technology, industrial software, and
services based on best-in-class technology platforms like Totally Integrated Automation (TIA) or
Integrated Drive Systems (IDS). We work in close partnership with you to develop sustainable
solutions across the entire lifecycle – from design and engineering to modernization. We rely on
standardized components wherever possible, complementing these with industry-specific solutions
to meet customers‘ specific needs in all industry segments. This enables the availability of your
products, systems, and solutions over the long term. And with our strong focus on resource
efficiency, we contribute to environmental sustainability in every application.

The process industry is one of the core businesses of Siemens. Countless applications, installed
throughout a wide variety of industries, demonstrate our expertise. But even more important is the
value we add for our customers, enabling them to increase their productivity in every part of the
value chain. With our precise knowledge of the different market segments, we can help you respond
faster and more specifically to new market requirements and developments, and thus strengthen
your competitiveness.

 HEALTH CARE:
The separately managed business Siemens Healtheers AG is one of the world‘s largest
suppliers of medical infrastructure and is a leader in medical imaging, laboratory diagnostics
and clinical IT.
At Siemens Healthineers, we enable healthcare providers to increase value by expanding precision
medicine, transforming care delivery, improving patient experience, and digitalizing healthcare.

Healthcare providers around the world have long relied upon our engineering excellence – leading-
edge, high-quality medical technology across a broad portfolio. Our solutions touch an estimated

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five million patients globally every day1 and help hospitals to continuously improve their clinical,
operational, and financial outcomes.

Data is at the heart of what we do. We now consolidate the unprecedented volume of data and
insights derived from our installed base of over 600,000 running systems worldwide and turn them
into leading-edge enterprise and digital health services. This uniquely positions us to move the
business of healthcare forward by helping our customers realize new opportunities.

Partnerships are built on people. With Siemens Healthineers there is no team more committed and
more connected than we are to realize success together with our customers.

 WIND POWER:
The separately managed business Siemens Wind Power is a leading supplier of reliable,
environmentally-friendly and cost efficient renewable energy solutions. Driving down the cost
of wind power is the key target as the company strives to make renewable energy fully
competitive with conventional energy sources. Providing highly reliable and cost-efficient wind
turbines, Siemens Wind Power offers solutions to meet both business and environmental needs. With over
35,000 megawatts of wind power installed, our wind power solutions deliver clean, renewable energy from
offshore and onshore installations around the world.
Our platform strategy for onshore and offshore wind power plants is fundamental to bringing down
the costs of wind power. With innovations in blade design and generator technology, we boost
efficiency. At the same time, systematic modularization allows us to streamline the entire
manufacturing and installation process.

In offshore wind power, Siemens is the most experienced company within the industry. With the
creation of the world‘s first offshore wind power plant in 1991 in Denmark, Siemens established the
industry. Recent years‘ industrialization have seen Siemens set and break the records for the
world‘s largest offshore wind power plants, presently held by the 630 MW London Array project. It

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features 175 Siemens 3.6 megawatt wind turbines.
Siemens occupies a leading position within onshore wind power, having been awarded the world‘s
largest single onshore order to date: a 1,050 MW order from MidAmerican Energy in the USA for a
series of onshore wind power plants in Iowa.

4.2.2 FEATURES

 Strong Quality control standards that ensure excellent road worthiness of every unit they
make
 In house Research and Development team which works tremendously towards providing
better mobility solutions
 State of art production facility fitted with imported machinery to ensure precision
 Completely indigenous production methods and 100% indigenous product
 Highly Qualified transport designers and mechanical engineers with good exp erience of
Automotive Industry
 Best in the industry when it comes to fulfilling and delivering promises
 As compared to the competitors, their team comprises of young professionals, engineers,
technicians and managers who are flexible and open to new thoughts

4.2.3 VISION STATEMENT

A world of proven talent delivering breakthrough innovations giving the customers a unique
competitive edge enabling societies to master their most vital challenges and creating
sustainable value, within the scope of Siemens‘ core activities, to find the best way of
combining and developing know how and expertise, so that the company profitably channels
them into outstanding value for the customers.

It has been working on the following major objectives:

Aiming to capture and maintain leading market and technology positions in all the
businesses in order to achieve sustainable profitable growth and, thus, continually increase
the company value. The strategy is reflected in three strategic
directions: Focus on innovation-driven growth markets.

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 Figure 13 SIEMENS VISION

4.3 INDUSTRIAL COMPETANCE

4.3.1 GE’s MODULAR SUBSTATION AUTOMATION SYSTEM

1. Integrated Protection and Control, Modular Automation System

GE‘s Integrated Protection and Control Modular Automation System is a pre -engineered, pre-
packaged and pre-tested system that is:

• The system is connected with GE‘s Multiln Hard Fibre system eliminating the extensive use
of copper wires in the control room and in the field. Customers can realize a 50% saving in
cabling, trenching and conduit and this system can be deployed faster than legacy methods.
The system can be pre-packaged in a modular control house and dropped in or built to reside
in a control room.

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• A communication architecture built that can deliver higher network availability, redundancy
with Parallel Redundancy Protocol (PRP) and high throughput.

• An automation System delivering IED station bus integration with capabilities to integrate
the substation to an enterprise Energy Management or Distribution Management System.

• Cyber security compliant across the entire system design

2. Modular Protection and Control System with Process Bus

GE's Modular Protection and Control System with Process Bus consists of a pre -built and
pre-commissioned protection and control system based on the Multilin HardFiber system and
includes protection and control schemes for transformer, bus bars, and feeders. The offering is
designed for transmission, distribution, solar and wind interconnect and collector and
industrial substation applications.

This system uses pre-commissioned HardFiber Bricks in mounting cabinets connected to pre-
commissioned relay panels using fibre optic cables. The system can help customers reduce
costs for cabling, trenching and conduit as well as decrease installation and commission costs
due to less labour-intensive installation. The modular approach of this system allows
customers to drive down project costs and reduce project cycle times. Once installed, the
system provides customers with reduced maintenance and total cost of ownership.

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 Figure 14 Modular Automation System

4.3.2 ABB: BRIDGING THE GAP BETWEEN ANALOG AND DIGITAL

TECHNOLOGIES

ABB is synchronizing technologies for reliable power. Built on the international standard IEC
61850, ABB‘s world-leading digital substations achieve new heights in reliability,
interoperability and real-time performance. The digital substation can save lives, while
bridging the gap between the equipment of the process bus level and the station level.

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CHAPTER 5
REVIEW

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5. REVIEW
A well established company requires looking after multiple fronts, so was the case with
Siemens. An unfathomable advantage that such an industry provides to its employees is a
chance to learn and grow. As a result the project been allotted to me was diverse in its
background and the things that could be learnt. The project allotted to me in the internship
semester gave me a broad outlook of the both the technical and non -technical fields.

The project Wireless Transmission of Data required an in depth understanding of electrical

protection systems. The project was developed using a NodeMCU platform which is just like
the Arduino Board but has the wifi module inbuilt. Also second part of the project involves
use of the Blynk which was instrumental in making the HMI screen.

The entire task was carried out to address the problem of electrical losses which happen
between the transfer of current and voltage from the control centre to the switchyard and vice
versa. A lot of expense is inculcated while making use of Ethernet cables and Ethernet
switches. More importantly the redundant network has been made much more reliable via
omitting the wired transmission of electrical quantities. Another major advantage of wireless
transmission is the omission of cable scheduling. A lot of investment is being done in terms of
time and labour to organize the working and labelling of cables. Thus with the adoption of
wireless based technology this major difficulty shall overcome.

Overall the Wireless Transmission of Data offers much more reliability, a better redundant
network, a less expensive protection system and much more secured option

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CHAPTER 6

WORK DETAILS

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6. WORK DETAILS
6.1 WORK PROGRAMME:
My internship at Siemens Ltd. started on 4th January, 2018. From the very first day it was an
immensely helpful and learning experience for me. I started my training by exploring and
understanding the various types of protection system. This timeline will briefly explain the
course of my internship from the beginning till the end.

January 2018- The internship started with the essentials of the protection system which are to
be strictly adhered to. To avoid human error and to introduce regular checks, standardization
is a MUST and planning is necessary. The Engineering Manual being issued contains
Systems, methods and standards as relevant to present day operations in Engineering. The
manual shall be further revised from time to time to reflect improvisation, further
standardization and better alignment with manufacturing.

February 2018- We started with the drawing of various bus bar arrangements on AUTOCAD
along with the study on the present ways of transferring data through IEC 61850 protocol and
Ethernet cables so that a better and more reliable mode of data transmission could be
proposed. I visited the DEMO LAB to understand the basic wiring of panels and RTU
(Remote Terminal Unit).

March 2018- I started learning to work with Tinker cad (supported by Autodesk), which was
equivalent to working with ARDUINO UNO. But on a later stage of the project, we realized
that the wifi module was missing in the software. So eventually we had to change the
simulation medium. A lot of simulators like FRITZING, PROTEUS etc were worked upon.
Finally hardware based project was decided.

April 2018- With adequate background to implement the wireless transmission of data, this
month was used to develop the project on NODEMCU. Coding was learnt on arduino
background. Use of BLYNK App was learnt.

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6.2 PROTECTION OF POWER SYSTEM
The objective of power system protection is to isolate a faulty section of electrical power
system from rest of the live system so that the rest portion can function satisfactorily without
any severe damage due to fault current. Actually circuit breaker isolates the faulty system
from rest of the healthy system and these circuit breakers automatically open during fault
condition due to its trip signal which comes from protection relay. The main philosophy a bout
protection is that no protection of power system can prevent the flow of fault current through
the system, it only can prevent the continuation of flowing of fault current by quickly
disconnect the short circuit path from the system. For satisfying this quick disconnection the
protection relays should have following functional requirements.

6.2.1 BASIC WORKING OF PROTECTION SYSTEM

Figure 15 Basic Protection System

In the picture the basic connection of protection relay has been shown. The secondary of
current transformer is connected to the current coil of relay. And secondary of voltage
transformer is connected to the voltage coil of the relay.

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Whenever any fault occurs in the feeder circuit, proportionate secondary current of the CT
will flow through the current coil of the relay due to which mmf of that coil is increased. This
increased mmf is sufficient to mechanically close the normally open contact of the relay. This
relay contact actually closes and completes the DC trip coil circuit and hence the trip coil is
energized. The mmf of the trip coil initiates the mechanical movement of the t ripping
mechanism of the circuit breaker and ultimately the circuit breaker is tripped to isolate the
fault.

6.2.2 IMPORTANT ELEMENTS FOR POWER SYSTEM PROTECTION

 SWITCHGEAR
Consists of mainly bulk oil circuit breaker, minimum oil circuit breaker, SF6 circuit breaker,
air blast circuit breaker and vacuum circuit breaker etc. Different operating mechanisms such
as solenoid, spring, pneumatic, hydraulic etc. are employed in the circuit breaker. Circuit
breaker is the main part of protection system in power system and it automatically isolate the
faulty portion of the system by opening its contacts.

 PROTECTIVE GEAR
Consists of mainly power system protection relays like current relays, voltage relays,
impedance relays, power relays, frequency relays, etc. based on operating parameter, definite
time relays, inverse time relays, stepped relays etc. as per operating characteristic, logic wise
such as differential relays, over fluxing relays etc. During fault the protection relay gives trip
signal to the associated circuit breaker for opening its contacts.

 STATION BATTERY
All the circuit breakers of electrical power system are DC (Direct Current) operated. Because
DC power can be stored in battery and if situation comes when total failure of incoming
power occurs, still the circuit breakers can be operated for restoring the situation by the power
of storage station battery. Hence, the battery is another essential item of the power system.
Some time it is referred as the heart of the electrical substation.

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An electrical substation battery or simply a station battery containing a number of cells
accumulate energy during the period of availability of AC supply and discharge at the time
when relays operate so that relevant circuit breaker is tripped at the time fa ilure of incoming
AC power.

6.3 TRIP CIRCUIT SUPERVISION

There are different contacts connected in series along a trip circuit of an electrical circuit
breaker. There must be some situation when the circuit breaker should not trip even a faulty
current passes through its power contacts. Such situations are low gas pressure in SF6 circuit
breaker, low air pressure in pneumatic operated circuit breaker etc. In this situation the trip
coil of the CB must not be energized to trip the CB. So there must be NO contacts associated
with gas pressure and air pressure relays, connected in series with breaker trip coil. Another
scheme of trip coil is that it should not be re energized once the circuit breaker is opened.
That is done by providing one NO contact of breaker auxiliary switch in series with trip coil.
In addition to that the trip circuit of a CB has to pass through considerable numbers of
intermediate terminal contacts in relay, control panel and circuit breaker kiosk.

So if any of the intermediate contacts is detached, the circuit breaker fails to trip. Not only
that, if DC supply to the trip circuit fails, the CB will not trip. To overcome this abnormal
situation, trip circuit supervision becomes very necessary. The figure below shows the
simplest form of trip circuit healthy scheme. Here a series combination of one lamp, one push
bottom and one resistor is connected across the protective relay contact as shown. In healthy
situation all the contacts except protective relay contact are in close position. Now if push
bottom (PB) is pressed, the trip circuit supervision network is completed and lamp glows
indicating that the breaker is ready for tripping.

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 Figure 16 Trip Supervision -CB is closed

The above scheme is for supervision while circuit breaker is closed. This scheme is called
post close supervision. There is another supervision scheme which is called pre and post close
supervision. This trip circuit supervision scheme is also quite simple. The only difference is
that here in this scheme, one NC contact of same auxiliary switch is connected across the
auxiliary NO contact of the trip circuit. The auxiliary NO contact is closed when CB is closed
and auxiliary NC contact is closed when CB is open and vice versa. Hence, as shown in the
figure below when the circuit breaker is closed the trip circuit supervision network is
completed via auxiliary NO contact but when the circuit breaker is open the same supervision
network is completed via NC contact.

The resistor is used series with the lamp for preventing unwanted tripping of circuit breaker
due to internal short circuit caused by failure of the lamp.

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 Figure 17 Auxiliary contact completes circuit

So far whatever we have discussed it is only for locally controlled installation but for a
distance control installation, relay system is necessary. The figure below shows the trip circuit
supervision scheme wherever a remote signal is required.

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 Figure 18 Trip Supervision: remote signal required

When trip circuit is healthy and circuit breaker is closed, relay A is energized which closes
the NO contact A 1 and hence relay C is energized. Energized relay C keeps NC contact in
open position. Now if the circuit breaker is open, relay B is energized which closes No
contact B 1 hence relay C is energized. As C is energized, it keeps the NC contact C 1 in open
position. While CB is closed, if there is any discontinuity in the trip circuit relay A is de-
energized which opens contact A 1 and consequently relay C is de-energized and which make
the NC contact C 1 in close position and hence alarm circuit is actuated.

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Trip circuit supervision is experienced by relay B with the circuit breaker is open in a
similar manner as relay A with the circuit breaker is closed. Relays A and C are time -delayed
by copper slugs to prevent spurious alarms during tripping or closing operations. The resistors
are mounted separately from the relays and their values are chosen such that if any one
component is inadvertently short-circuited, a tripping operation will not take place. The alarm
circuit supply should be separated from main trip supply so that the alarm can be actuated
even the trip supply failed.

6.4 DATA COMMUNICATION IN SAS

Substation data communication system plays a critical role in the real time mission critical
operation of substation automation system. All secondary equipment within a substation is
interlinked with communication buses. In conventional substation, legacy communication
devices typically relied on one-way communication. Serial communication buses or
proprietary communication media with associated protocols are used for local HMI, as well as
for remote SCADA (Supervisory Control and Data Acquisition) communication. Modern
communication in substation is data transmission inside and between station level, bay level
and process level. The data information includes control, report; log GOOSE, SV, etc.

Communication between these 3 levels is called vertical communication and connected by

high-speed Ethernet station bus and process bus. Station bus facilitates communication
between station level and bay level. Process bus will be used for time critical messages
between process level and bay level. Most of the substation protection and control functions
will rely on the performance of the process bus.

Communication within one level is horizontal communication. In station levels, the time
based data from multiple bays or substation level database will be analyzed and processed.
The control commands for the primary equipment (e.g. circuit breakers) will be submitted and
data like voltage, current and power factor will be collected.

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In bay level, protection unit and control unit collect data from bays and perform actions on the
primary (e.g. power circuit) equipment. In process level, performance and condition
information are read from essential station equipment. Control commands from bay level will
be received and executed in the equipment at the process level.

6.5 STANDARDS AND PROTOCOLS USED

Communication protocols define the architecture of substation automation communication

systems. They determine the way of information traffic between control stations, IEDs and
other communication devices. Generally there are 3 different standards categories for
substation communication:

• Proprietary/vendor specification, e.g. UCA and DNP3, etc.

• National standard, e.g. IEEE 1613, etc.

• International standard, e.g. IEC 60870-5101/104, IEC 60870-6-TASE.2, IEC 61850,.

Communication networks in substations will often have lower-level data link, physical layer
protocols and multiple application layer protocols running ―on top of‖ TCP/IP.

In the past and present, there are over 50 communication protocols for legacy substation
automation systems. These include Modbus TCP, ProfiNet, Ethernet IP, OPC-DA, and LON
for example. Many of these topologies are vendor specified and have serial interface, low
bandwidth, limited network devices, serial interfaces and inflexible data, etc. Their
communication architecture does not fit to the corporate communication technology and are
not able to expend the network. Most representative protocols are DNP3 and IEC 6 0870-5-
104. Both of them are master/slave based field bus communication and can only be
implemented till station level and bay level.

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Nowadays many substation vendors are moving away from serial to Ethernet based IEC
61850 which is a client/server communication standard. It fully supports the interoperability
among IEDs supplied by different vendors in the substation and can be applied also in process
level in substation automation.

6.6 WIRED COMMUNICATION

Wired communication refers to the transmission of data over a wire-based communication

technology. It offers more secure and reliable connection since data is not being transmitted
through the air.

The traditional wired communications are:

• Supervisory control and Data Acquisition (SCADA) which has limited bandwidth, 75bits/s
to 2400bits/s. Higher bandwidth is necessary for monitoring (detection of abnormality),
control and management tasks.

• When feeders are considered, PLC is well-suited, because it is a medium that is available
throughout the distribution system. PLC has potential to transmit data at a maximum rate of
11 Kbit/s; when the PLC has sufficient robustness and reliability, this maximum data rate can
be achieved only in a narrow frequency range of 9-95 kHz. This low rate of communication is
not ideal for secure communication. Therefore, if more information has to be sent from all the
components in a feeder, higher bandwidth is required.

• Dedicated wired communication is another option. Interference an d attenuation is one of the

main problems with copper wire connections. A fibre optic cable is the solution for
interference but increases the cost. In addition to above, this will have some drawbacks like,
require physical connections and will reduce the flexibility. Further when a pole goes down,
the communication link will be broken and may result in poor performance.

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6.7 WIRELESS COMMUNICATION :

Wireless communication will transfer the information over a long distance without the use of
electrical conductors or wire. It provides more flexibility than wire based means of
communication and continues to play a significant role in the modernization of the electric
power system. Examples of modernization efforts related to increased communications in the
electric power system to improve reliability and efficiency. Accurate location and prediction
of T & D disturbances and failures are still in early stage of development. More reliable
approach can be developed by improving communication infrastructure; this would results in
better asset management. Wireless technologies have significant benefits over wired, such as
improved protection, control, speed outage restoration, substation monitoring and
management, power system operation analysis, maintenance, planning and also have low
installation and maintenance cost, rapid deployment, mobility, etc. Several activities are going
on in many areas of power system using this technology. Interference in the presence of
buildings and trees is the disadvantage of wireless communication which could result in
multi-path; using improved receivers and directional antennas can overcome this drawback,
which will increase the cost. Another problem is security issues. This can overcome by using
secure protocol, encryption and decryption technologies

6.8 IEC 61850

The IEC 61850 protocol standard for substation enables the integration of all protection,
control, measurement and monitoring functions by one common protocol. It provides the
means of high-speed substation applications, station wide interlocking and other functions
which needs intercommunication between IEDs. The well described data modelling, the
specified communication services for the most recent tasks in a station makes the standard to
a key element in modern substation systems.

IEC 61850 is a standard for communication networks and systems for power utility
automation and is being produced by IEC Technical Committee 57 Working Groups 10.

It is developed based on Utility Communications Architecture 2.0 (UCA2.0) which is based

on the Manufacturing Message Specification (MMS).

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IEC 61850 is a lower-layer object-oriented protocol being implemented over TCP/IP and
Ethernet networks. It defines a vendor independent communication infrastructure allowing
seamless IEDs integration.

Compare to DNP3 or IEC 60870-5-104, IEC 61850 is not only another way of providing the
same functions as a traditional SCADA protocol, it also provides information modes,
configuration languages and abstract services in substation communication.

Main features of IEC 61850 are as follows:

• It translates all in the information in the real substation into information models in the form
of standard naming conventions structures and formats for easy information management.

• It provides Abstract Communication Service Interface (ACSI) and makes it possible for
applications and databases to be unchanged with changes in the communication protocols and
media.

• It standardizes a Substation Configuration description Language (SCL) to describe

substation topology, information models, binding to process, communication and data flow,
etc. SCL can be used to exchange an IED‘s communication configuration information and
software from different manufacturers.

• It provides communication protocols of TCP/IP based SCADA, real time Generic Object
Orientated Substation Event (GOOSE) and Generic Substation Status Event (GSSE) and real
time sample measured value (SMV). GOOSEs support system protection applications and run
directly over Ethernet.

• It defines process bus which is supported by GOOSE and can minimize substation wiring
requirements in the yard by converting data of CTs/PTs to digital information.

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6.8.1 BENEFIT OF USING IEC 61850

IEC 61850 is the comprehensive standard for all communication functions in utility
applications. It is non-proprietary technology with multiple vendors and

provides inter- operability between devices and application functions through standardized
data models and information exchange. It realizes a highly flexible configuration of
communication networks and can greatly simplify substation automation architecture,
optimize the selection of devices for curtain application and increase efficiency.

IEC 61850 is a future proof standard for safe investment. By implementing IEC 61850, the
application model and communication stack can be separate. The applications can be modified
and extended without changing of the communication stack. It meets utilities‘ requirements to
combine products from a variety of manufactures for long term system exchangeability of
equipment and expandability.

6.9 SELECTION OF THE CABLE

While copper cabling is quite cheap and easy to use, copper covers only a limited distance of
a maximum 100 meters. Copper is also much more sensitive to EMI (electro-magnetic
interference) than fibre. Because of EMI, all Ethernet connections outside a cabinet and in
EMC sensitive environments should be made using fibre optics. Copper links should be used
only inside a cabinet or inside a building, while the cable length should be limited to 25
meters so it has an additional noise margin.

Copper connections for Gigabit Ethernet are not recommended because of long link set -up
times and lower noise margins.

For copper connections, CAT5e cables should be used at the least, CAT6 cable is even better.
Twisted pair cables should always be shielded. While Fast Ethernet needs only 2 pairs of
wires, Gigabit Ethernet requires 4 pairs. If for any reason the use of Gigabit Ethernet over
copper is a future possibility, 4 pairs of cables can be installed. Only direct cable should be
used, the auto-polarity function of the devices will automatically connect sender to receiver
pairs.

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For fibre optic links, multimode fibre with a 50 µm core diameter is recommended. This can
be used up to 2,000 meters for Fast Ethernet and up to 550 meters with Gigabit Ethernet. If
longer distances have to be covered, the use of single-mode fibre with a 9µm core diameter is
possible. In this case the link distance can be up to 10 kilometres.

All fibre connections should be operated at an optical wavelength of 1.300 nm, which means
100BaseFX standard for Fast Ethernet and 1000BaseLX standard for Gigabit Ethernet.

6.10 MODES OF COMMUNICATION

The communication infrastructure in the medium-voltage and low-voltage distribution
systems is usually heterogeneous, and the suitable technologies depend to a large extent on
the local topology (large city, rural region, distances, etc.). It must therefore be specif ically
tailored for each customer. In general, the following communication technologies are
available:

 Fibre-optic or copper communication cables are the best option, if present

 Power line carrier systems for medium-voltage and low-voltage networks

 Setup of own private wireless networks (e.g., wireless mesh, private Enterprise -Wi MAX /
LTE, or UHF Evolution), when spectrum is available at reasonable prices or local
regulations allow for it.

 Public wireless networks, depending on the installation for narrowband communication in

the kbps range (e.g., GPRS), or in the Mbps range (e.g., LTE). Attractive machine -to
machine (M2M) data tariffs and robust communication in case of power outages are key
ingredients to make this communication channel a viable option.

Depending on the applications being installed inside the RMU, an Ethernet switch / router
might be needed in order to concentrate the flow of communications. These data concentrators
can be implemented as customized solutions or integrated, for example, in the RTU (remote
terminal unit). To meet these requirements, Siemens offers a full range of all above -
mentioned communication technologies including rugged switches and routers that comply
with energy industry standards.

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6.10.1 FIBRE OPTICS

The best choice for all communications needs Fibre optics is the best transmission medium for
medium- and low-voltage applications because it is robust and not susceptible to
electromagnetic disturbances or capacity constraints. That‗s why grid operators who choose
this technology will be well prepared when their communications needs multiply in the future.
Fibre-optic cables are laid underground to connect individual substations. This work is
associated with heavy civil works, and therefore with great expense. However, when new
power cables are installed the cost-benefit analysis paints a clear picture. Fibre-optic cables
should generally be the first choice in this case.

6.10.2 POWER LINE CARRIER SOLUTIONS

For low- to medium-voltage applications, using the existing power line Standards-based
power line carrier solutions provide an attractive communication channel for all applications
in medium-voltage and low-voltage Smart Grid scenarios. They use the utility-owned
infrastructure in the distribution network, and provide a reliable and affordable
communications channel. Therefore, PLC solutions are especially useful for connecting
elements in grids, where no other reliable communication channel is available. They
transform the DSOs assets into a highly capable Smart Grid communication infrastructure.
With its throughput, low latency and high reliability, PLC solutions serve for distribution
automation applications as well as for backhauling data from metering applications in the
medium-voltage grid. As with every communication technology, the transmission range and
bandwidth provided by the PLC solution depends on the quality of the used transmission
medium. In case of the transmission over power lines, type and age of the power cable as well
as the number of joints have an impact on the achievable results. Consequently, a PLC
network needs to be engineered and planned correctly to provide maximum performance.

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6.10.3 ENTERPRISE WI MAX/ LTE

The main application area for private WiMAX / LTE systems, specifically tailored to the
needs of enterprises in vertical markets, is backhauling of RMUs, data concentrators or
Distributed Energy Resources (DER). Single prosumers could technically be served, but this
is economically reasonable only in selected cases. WiMAX (Worldwide Interoperability for
Microwave Access) is a standards-based telecommunications protocol (IEEE 802.16 series)
that provides both fixed and mobile broadband connectivity. The advanced point -to-
multipoint technology is field-proven and deployed globally. In the past, certain
manufacturers have evolved the system for the requirements of specific vertical markets such
as oil and gas or power utilities. Differing from telecommunication-carrier-oriented systems,
these implementations support special features such as asymmetric prioritization of uplink
traffic, layer-2-based traffic (multicast / IEC 61850 GOOSE), redundancy options, as well as
economic system scaling fitting also for smaller, privately owned regional or local networks.
Besides the application requirements, it is important to assess regional conditions like area
topology and availability of radio spectrum. Professional radio network planning and network
engineering are mandatory when setting up private broadband radio networ ks.

6.10.4 WIRELESS MESH

In general, wireless mesh networks are composed of cooperating radio nodes that are
organized in a mesh topology. The link communication technology from one hop to another
can be standardized or proprietary (e.g., FHSS, OFDM technologies). The mesh protoc ols and
corresponding forwarding algorithms are on the other hand still predominantly proprietary.
Standardization efforts in this area (e.g., 6LoWPAN protocol suite / Zigbee -NAN) are
currently still ongoing. Thanks to their mesh properties along with self-setup and self-healing
mechanisms, mesh networks inherently offer ease of operation and redundancy for fixed
applications. The system performance can be characterized by the hops‘ throughput capacity,
the average reach of a hop-to-hop link, and the max number of hops on a single path. Detailed
requirements as well as specific regional conditions must be carefully assessed in order to
select the best-suited technology.

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6.11 INTERNET OF THINGS

The IoT is defined as a network that can connect any object with the Internet based on a
protocol for exchanging information and communication among various smart devices in
order to achieve monitoring, tracking, management and location identification objectives. The
IoT focuses on the realization of three main concepts, namely things-oriented, Internet-
oriented and semantic-oriented. The things oriented concept involves smart devices, such as
the Global Positioning System (GPS). The Internet oriented concept enables communication
among smart devices through various communication technologies, such as ZigBee, WI-Fi,
Bluetooth and cellular communications and connects them to the Internet. The semantic
oriented concept realizes a variety of applications with the help of smart devices. Over the
past few years, the IoT technology has gained significant attention in various applications,
and has allowed for the interconnection of the Internet to various network embedded devices
used in daily life. It has automated the operation of various systems, such as health care,
transportation, military, home appliances, and security, surveillance, agriculture and power
grids. In some areas, IoT devices are equipped with transceivers, micro controllers and
protocols, enabling their communication with other devices as well as with extern al entities to
allow the realization of completely automated systems.

The SG completely revolutionizes the energy generation, transmission, distribution and

consumption in four sub-systems. It is comprised of three types of networks, a Home Area
Network (HAN), a Neighbourhood Area Network (NAN) and a Wide Area Network (WAN).

6.11.1 HOME AREA NETWORK (HAN)

HAN is the first layer; it manages the consumers‘ on-demand power requirements and
consists of smart devices, home appliances (including washing machines, televisions, air
conditioners, refrigerators and ovens), electrical vehicles, as well as renewable e nergy sources
(such as solar panels). HAN is deployed within residential units, in industrial plants and in
commercial buildings and connects electrical appliances with smart meters.

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HANs may have either a star topology or a mesh topology. The preferred communication
technologies for HANs are power line communications (wired technology), ZigBee, Bluetooth
and Wi-Fi (wireless technologies). A HAN is comprised of a variety of IoT smart devices,
such as a home gateway, smart meters, sensor and actuator nodes, smart home appliances and
electric vehicles. A home gateway connects to smart meters and periodically collects power
consumption data of the home appliances. HANs perform two-fold functions, commissioning
and control. The commissioning function identifies new devices and manages the devices. The
control function enables communication among smart devices by establishing the links and
performs reliable operation for the various SG layers. A HAN uses two -way communications
for demand response management services [60]–[62]. In the forward communication
direction, the smart meters‘ load and real-time power consumption information of the home
equipment, connected to IoT smart devices, are collected by home gateways and transmitted
from the consumer side (the HAN) to the NAN to be forwarded to a utility centre. In the
backward communication direction, the home gateway acts as a central node and receives
dynamic electricity pricing information from the NAN, which is then provided to smart
meters or IoT smart devices for triggering the required action for home appliances.

6.11.2 NEIGHBOURHOOD AREA NETWORK

NAN, also known as Field Area Network (FAN), is the second layer of an SG and consists of
smart meters belonging to multiple HANs. NAN supports communication between
distribution substations and field electrical devices for power distribution systems. It collects
the service and metering information from multiple HANs and transmits it to the data
collectors which connect NANs to a WAN.

The communication technologies for NANs need to cover a radius of a thousand meters. The
communication channels between smart meters and data aggregation points therefore must be
interference free [63]. A gateway in the NAN collects consumers‘ energy consumption data
from smart meters in HANs and transmits the collected data to the utility companies through
either private or public WANs. Basically, the topology of a NAN is c omprised of two types of
gateways, NAN gateways and HAN gateways. A NAN gateway connects various HAN
gateways and serves as an access point to provide a single hop connection to HAN gateways
in a hybrid access manner. The HAN gateways transmit their energy consumption data to

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NAN gateways through either wired (e.g., PLC, DSL) or wireless (e.g., cellular, mobile
broadband wireless access or digital microwave technology) communication technologies .

6.11.3 WIDE AREA NETWORK

WAN is the third layer of an SG and it serves as a backbone for communication between
network gateways or aggregation points. It facilitates the communication among power
transmission systems, bulk generation systems, renewable energy sources and control centres.

The WAN is the backbone for communication between network gateways, NANs, distributed
grid devices, utility control centres and substations. It is comprised of two interconnected
networks, core networks and backhaul networks. The core network provides communication
to utility control centres with low latency and high data rate through fibre optics or cellular
communications. The backhaul networks provide broadband connections and monitoring
devices to NANs through wired (e.g., optical networks, DSL), wireless (e.g., cellular network,
mobile broadband wireless access) or hybrid fibre-wireless networks.

Figure 19 Power flows: Subsystem; Information flows: Networks

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 6.12 CONTROLLER USED: NODE MCU

The NodeMCU (Node MicroController Unit) is open source software and hardware
development environment that is built around -on-a-Chip called the ESP8266. The ESP8266,
designed and manufactured by Espressif Systems, contains all crucial elements of the modern
computer: CPU, RAM, networking (wifi), and even a modern operating system and SDK..
However, as a chip, the ESP8266 is also hard to access and use. You have to solder wires,
with the appropriate analog voltage, to its PINs for the simplest tasks such as powering it on
or sending a keystroke to the "computer" on the chip. And, you have to progra m it in low-
level machine instructions that can be interpreted by the chip hardware. While this level of
integration is not a problem when the ESP8266 is used as an embedded controller chip in
mass-produced electronics.

The NodeMCU project aims to simplify ESP8266 development. It has two key components.

1. An open source ESP8266 firmware that is built on top of the chip manufacturer's proprietary
SDK. The firmware provides a simple programming environment based
on eLua (embedded Lua), which is a very simple and fast scripting language with an
established developer community. For new comers, the Lua scripting language is easy to
learn.
2. A DEVKIT board that incorporates the ESP8266 chip on a standard circuit board. The board
has a built-in USB port that is already wired up with the chip, hardware reset button, wifi
antenna, LED lights, and standard-sized GPIO (General Purpose Input Output) pins that can
plug into a bread board.

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 Figure 20 NodeMCU Pin Diagram

 The ESP8266 chip requires 3.3V power supply voltage. It should not be powered with 5 volts like
other arduino boards.

 NodeMCU ESP-12E dev board can be connected to 5Vusing micro USB connector or Vin pin
available on board.

 The I/O pins of ESP8266 communicate or input/output max 3.3V only. i.e. the pins are NOT 5V
tolerant inputs
 Uses simple LUA based programming language.
 Event-driven API for network applications
 10 GPIOs:- D0-D10,
 ADC:- A0
 Wifi networking

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6.13 BLOCK DIAGRAM

Current BLYNK
Sensor Wi-Fi Module
SERVER

DC SUPPLY
Node MCU

CIRCUIT ISOLATOR EARTHING

BREAKER SWITCH

CLOSE OPEN

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6.14 CONTROL CENTRE REPRESENTATION: BLYNK

Blynk is a Platform with iOS and Android apps to control Arduino, Raspberry Pi and the likes
over the Internet. It‘s a digital dashboard where you can build a graphic interface for your
project by simply dragging and dropping widgets. It‘s really simple to set everything up.

Blynk is not tied to some specific board or shield. Instead, it's supporting hardware of your
choice. Whether your Arduino or Raspberry Pi is linked to the Internet over Wi-Fi, Ethernet
or this new ESP8266 chip, Blynk will get you online and ready for the Internet Of Your
Things.

Figure 21 Blynk

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6.14.1 NEED OF BLYNK

 HARDWARE (An Arduino, Raspberry Pi, or a similar development kit).

Blynk works over the Internet. This means that the hardware should be able to connect to
the internet. Some of the boards, like Arduino Uno will need an Ethernet or Wi-Fi Shield to
communicate, others are already Internet-enabled: like the ESP8266, Raspberry Pi with Wi-Fi
dongle. But even if you don‘t have a shield, you can connect it over USB to your laptop or
desktop. Another advantage is that the list of hardware that works with Blynk is huge and will
keep on growing.

 A SMARTPHONE

The Blynk App is a well designed interface builder. It works on both iOS and Android
6.14.2 WORKING OF BLYNK

Blynk was designed for the Internet of Things. It can control hardware remotely, it can
display sensor data, and it can store data, visualize it and do many other cool things. There are
three major components in the platform:

 Blynk App - allows to you create amazing interfaces for your projects using various
widgets we provide.
 Blynk Server - responsible for all the communications between the smart phone and
hardware. You can use our Blynk Cloud or run your private Blynk server locally. It is
open-source, could easily handle thousands of devices and can even be launched on a
Raspberry Pi.
 Blynk Libraries - for all the popular hardware platforms - enable communication with the
server and process all the incoming and out coming commands.

6.14.3 FEATURES

 Similar API & UI for all supported hardware & devices

 Connection to the cloud using:

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  Wi-Fi
 Bluetooth and BLE
 Ethernet
 USB (Serial)
 GSM
 Set of easy-to-use Widgets
 Direct pin manipulation with no code writing
 Easy to integrate and add new functionality using virtual pins
 History data monitoring via History Graph widget
 Device-to-Device communication using Bridge Widget
 Sending emails

6.14.4 SETTING BLYNK WITH NODEMCU

 The blynk app has set of library files which have to be included in the Arduino IDE
environment before the project is executed.
 Once the Zip file is downloaded, extract it and individually copy all the folders to your libraries
folder of your arduino.

 Once done just open Arduino IDE and go to Sketch-> Include libraries and you would see blynk
in the menu.

 If you see that then libraries have been included successfully.

 Include the board configuration in the Arduino IDE

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 Figure 22 Setting Blynk

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 Figure 23 Inserting the libraries

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 Figure 24 Selection of Board

Board configuration:

It contains all the essential parameters which are required to get the board booted and configured.
For example in if you go to Tools->Board Menu you would see a list of boards. All this boards
listed have different configuration settings. Therefore we should also include NodeMCU's board
configurations which typically contain the board architecture, clock speed, baud rate etc.

 In the Arduino IDE go to File->Preferences

 Now Copy the below link and paste it in the Additional Boards Manager Url text box
http://arduino.esp8266.com/stable/package_esp8266c...

 Restart the Arduino IDE after that.

 Now after restarting the Arduino IDE , go to Tools->Boards and select Node MCU board, mine
was version 0.9

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6.14.5 SETTING THE BLYNK

 First install the Blynk app from Google play store and then sign in.
 After that Press on click on New Project and you will get a screen (Refer Screen shots)
 Enter the name of your project.
 Then Select the Board as ESP8266.
 And then you will see below the authentication token no. If you want it in your email you can
send it through email also
 And then Finally click on to the create
button
 Now you will get your dashboard
screen. Just click on the the top most
button "+" on the right corner to add
widgets to your project.
 In this project we add a simple button
and then configure its settings as
Digital GP13 pin.(Refer Screen
Shots)
 It‘s your choice you can either have
the button set as push type or as a
switch

Fig
ure 25
Create new
Project

 Then label the Button as ON and OFF in the settings

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 Figure 26 Mail the Auth Token

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 Figure 27 Select the components

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 6.14.6 CIRCUIT DIAGRAM
Connections have been made as per the diagram.

A0 D0

D1
Current
sensor

D2

Potentiometer D3

D5

DC Supply
D6

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HARDWARE:
 Resistance 100 ohms
 Bread Board
 Current sensor
 Dc supply
 Node MCU
 Led
 Hook-up wires

6.14.7 UPLOAD THE CODE

 Connect your Esp8266 Wifi to your PC. Open Arduino IDE

 Then go to File->Examples->Blynk- Boards_Wifi->Esp8266Standalone

 Select the correct board (NodeMCU 1.0) and the com port from the Tools Menu

 Serial. begin(9600); // Change Baud Rate to 115200

 Blynk. Begin(auth, "sid", "pass"); // Enter your Wifi SSID and password, both inside the double
quotation

 Finally Save the file and Press Upload

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 Figure 28 Upload the code

6.14.8 FINAL EXECUTION

 After uploading the code ,open the Blynk app in the Phone
 Connect to the internet
 Then you would see your dashboard with a button
 Press Play button on the top most right corner of the app
 Press the Button and you would see the LED Turn ON.

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 Figure 29 Final Circuit

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 Figure 30 HMI: Control Centre

6.15 SOFTWARE SIMULATORS

Arduino simulators are the perfect platforms for programmers and designers who want to learn the
basics of circuit schematics and design. With the help of an Arduino simulator, one can get an
avenue to learn without being afraid that you will damage your board and design equipment.
Students who face challenges purchasing electrical equipment without any clue on how they‘ll work
can eliminate trial and error mistakes with the help of Arduino simulators, saving both time and
money.

Another advantage of Arduino simulators is the fact that they support line to line debugging and the
user will identify exactly the spot where things went wrong. Arduino simulators come in all kinds
of forms, and they have been developed in such a way to be compatible with the main OSs.

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6.15.1 AUTODESK EAGLE

Autodesk Eagle provides powerful and easy to use tools for every engineer out there. You can now
bring your electronic inventions to life with the help of a complete set of PCB layout and schematic
editing tools, community-driven features and library content.

The key features of Eagle include the following:

 Schematic editor
 Modular design blocks – you can reuse the existing blocks of circuitry.
 Multi sheet schematics – you can keep designs of any size organized.
 Electrical rule checking – you will finally be able to have confidence in your schematic
design.
 Real-time design synchronization – you can stay in-sync between schematic and PCB
layout.
 PCB Layout editor
 BGA fan-out – you can escape from your BGA in seconds.
 High-speed design – you can design with the latest technologies, including DDR4, PCI
Express, or USB-C.
 3D models for PCB layout – you can unite your PCB and enclosure seamlessly.
 Complete components – this is the one-stop shop for reviewing your component needs.
 User language programs (ULPs) – you can improve your design tool process.

6.15.2 PROTEUS

Proteus is a great Arduino simulator that combines simplicity with its various features and manages
to make Arduino simulation seem like the easiest thing. This simulator managed to make inroads in
all kinds of industries such as education, automotive, and IoT. It‘s compatible with both Linux and
Windows, and there are lots of things to know about its offerings and its vibrant community.

The most prominent and exciting feature of Proteus is its ability to simulate the interaction between
software running on a microcontroller and any digital/analog electronics connected to it. The
microcontroller model sits on the schematics together with the other elements of your product
design. Just like a real chip, it simulates the execution of your object code.

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Proteus includes various virtual instruments such as Oscilloscope, Logic Analyser, Function
Generator, Pattern Generator, Counter Timer and Virtual Terminal and also simple voltmeters and
ammeters. More than that, Proteus provides dedicated Master/Slave/Monitor mode protocol
analyzers for SPI and I2C – you simply have to wire them onto the serial lines and control/interact
with the data live during the simulation process.

Proteus offers an invaluable and inexpensive way to get your communication software right before
hardware prototyping.

Proteus also allows the following operations:

 Debugging: it can perform simulations in single step modes, and it works just like a
debugger.
 Diagnostics: Proteus is equipped with comprehensive diagnostics or trace messaging.
 Co-simulate both low and high-level micro-controller code in the context of a mixed-
mode SPICE circuit simulation.
 Proteus improves efficiency, flexibility, and quality all over the design process

6.15.3 AUTODESK CIRCUITS

Autodesk Circuits allows you to bring your ideas to life with online free and easy to use tools. In
case you are only a beginner, you can start with more simple experiments in the Circuit Scribe or
the Electronics Lab. Users who are more experienced can skip ahead and go straight to PCB
Design.

Electronics Lab Hub includes the following:

 Real-time simulation: you can design and prototypes before you build a circuit in real life; you
can use anything from resistors, capacitors, and potentiometers all the way to oscilloscopes.
 Arduino programming: you can program and simulate any Arduino code in the editor, and
you‘ll have a full serial monitor and a growing collection of various supported Arduino
libraries.
 Collaborative editing: you can invite others to collaborate in real-time on your designs.

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 Circuit Scribe Hub allows you to design and simulate circuits, and then print and share your
templates. You can also embed your design and learn from the community of the developers of
Autodesk Circuit.

PCB Design Hub includes the following features:

 Schematic design: you can choose from a growing component library by the community, or you
can create your own components.
 PCB Layout: this includes all the tools that you need such as copper trace, copper fill, via and
drill holes and lots of silk screen tools.

Learning to code is much easier when you can program things that really work. Autodesk Circuits is
a free tool.

6.15.4 FRITZING

Fritzing is an open source hardware initiative that makes electronics accessible as a creative
material for everyone who is interested in the subject. The website provides a software tool,
community, and services in the spirit of Arduino and processing and it fosters a creative ecosystem
that allows users the following:

 Documenting their prototypes

 Sharing the prototypes with others
 Teaching electronics in a classroom
 Layout and manufacturing professional PCBs

With Fritzing, you can inexpensively and quickly turn your circuit into a real custom-made PCB.
This tool can only act as a creative platform if lots of users are using it as a means of learning and
sharing.

You can learn a tremendous amount of things from the many tutorials available. Here are some of
the most interesting ones:

 Building a Circuit
 Using a Strip board
 Working with SMD parts

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  Creating Paper Templates
 Curvy Wires and bendable Legs
 Designing a PCB
 One minute Arduino Shield design
 Double-sided routing
 Producing a PCB
 Soldering SMD parts
 Creating custom Parts
 Attaching Programming Code.

It is also interesting to know that Fritzing turned from a publicly funded research project into a non-
profit organization. This means that to make it self-sustaining and to continue the development
Fritzing is offering a few services that include the following:

 Fritzing Fab – With the Fritzing Fab, the PCB production service, you can quickly and
inexpensively turn your sketches into professional PCBs.
 Workshops – There are lots of workshops on Arduino, Fritzing and everything related,
which are offered to beginners and professionals.
 Part Creation – You can also have your product featured in Fritzing, and if you don‘t want to
do it yourself, you can hire the developers to create high-quality parts.
 Products – Fritzing has created an educational starter and upgrade kit.

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CHAPTER 7
CONCLUSION AND
FUTURE SCOPE

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7. CONCLUSION AND FUTURE SCOPE
7.1 CONCLUSION

The project semester gave a deep insight into the electric protective industry in regards to standards,
products and technology being developed. A major part of the project involved in making a
redundant power protection system and reducing the cost and losses which would have been there
because of Ethernet cables and wires.

The primary task of understanding the present protection systems, analyzing the various
components, their working, the various protocols used for communication between different IDEs
gave a deep insight of the working of a substation.

This project was innovative approach to counter the existing issues in the company .Working under
these projects has not only helped evolve and enhance my personal soft skills but has also made me
realize my full potential. Being a well established company, it provided well rounded holistic
development

7.2 FUTURE SCOPE

IoT technology provides interactive real-time network connection to the users and devices
through various communication technologies, power equipment through various IoT smart
devices, and the cooperation required to realize real-time, two-way and high-speed data
sharing across various applications, enhancing the overall efficiency of a SG. The application
of the IoT in SGs can be classified into three types.

 IoT is applied for deploying various IoT smart devices for the monitoring of equipment
states.
 IoT is applied for information collection from equipment with the help of its connected
IoT smart devices through various communication technologies.
 IoT is applied for controlling the SG through application interfaces. IoT sensing devices
are generally comprised of wireless sensors, RFIDs, M2M (machine-to-machine) devices,
cameras, infrared sensors, laser scanners, GPSs and various data collection devices.

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The information sensing in an SG can be highly supported and improved by IoT technology.
The IoT technology also plays an essential role in the infrastructure deployment of data
sensing and transmission for the SG, assisting in network construction, operation, safety
management, maintenance, security monitoring, information collection, measurement, user
interaction etc. Moreover the IoT also enables the integration of information flow, power flow
and distribution flow in a SG. Additionally, existing SG architectures mainly focus on the
needs of power distributors to manage the complete power grid. The consumers are accessed
with a network of smart meters by means of General Packet Radio Service (GPRS) or other
mobile networks. The new reality where consumers may already have other smart home
infrastructures (such as Wi-Fi) has not yet been incorporated in the network communications
of existing SG architectures. While some architecture does consider existing smart home
infrastructures, they are not designed for scalability in large deployments. Th e protocols
specific to IoT and SG systems therefore cannot be directly applied to IoT -aided SG systems,
as they only consider the individual characteristics of either the IoT or the SG systems, which
is not sufficient for an integrated IoT-aided SG system.

The potential of renewable energy may depend, for example, on IoT -based prediction of
weather conditions that can regulate energy flow between different regions, and on
monitoring the efficiency of the involved equipment (solar panels, wind turbines).

Applications today tackle several areas of interest, such as:

• Surveillance of premises or of power equipment installations (towers and power

transmission lines);

• Adjusting home consumption by dynamic scheduling, this takes advantage of fluctuating

pricing;

• Meter reading and consumption monitoring, residential and commercial;

• Electric Vehicle charging and parking;

• Power demand and supply management, including integrated renewable energy sources; and

• Maintenance of power supply systems, by detecting line faults and failures.

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CHAPTER 8

IMPEDIMENTS AND
SUGGESTIONS

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8. IMPEDIMENTS AND SUGGESTIONS
8.1 IMPEDIMENTS

I take this opportunity to thank my respected mentors Mr. Govind Badhae making this
industrial training worthwhile and a great learning opportunity and Ms.Lovleen Kaur Taneja
for her able guidance that helped a lot throughout the semester.

Every novel idea no matter how vital, encounters a few roadblocks early on the road. Though
the training was successfully completed but still a number of difficulties were faced during
the internship tenure. Some of these difficulties arose during the project. Apart from these,
there were some difficulties which were operational in nature and were faced while
completing my day to day work in the company.

Because of my day to day work as a part of the internship program, it became difficult to
concentrate solely on my project. Sometimes, due to availability of a lot of work and limited
time, it became difficult to prioritize between my project and other short term engagements
which I was a part of. Though these engagements were an immense learning experience,
sometimes they stretched for long periods due to which I was unable to devote a lo t of time to
my project. Also, there were some rare instances when it became difficult to get help
regarding some technicalities of my project. So it took quite a lot of time to develop a
comprehensive understanding of the technicalities after thorough res earch and analysis.

However, I would like to state that my team and especially my team leader were very
supportive and always made it a point to help out whenever I faced any major difficulties. I
would like Siemens to continue the good work and keep on investing time in developing
different projects for interns to enhance and hone their technical skills.

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8.2 SUGGESTIONS

The project semester was one of the greatest opportunities an engineer can grab. There was so
much to learn and innovate. Whatever knowledge and experience I received from the
internship program was more than expected. But there is always a room for learning more.
Here are few suggestions that could be kept in mind by the college authorities and the
industry for future benefit.

8.2.1 INDUSTRY

Being a well established company of the work force, doesn‘t of yet have any in house specific
training and guiding centre for trainees and that the project and the related research work was
left upon the intern wholly, though that was a huge part of the learning process but still we
could have produced much better results with specialized guidance.

8.2.2 COLLEGE

Been working in a core based company, there can be some subjects included in the curriculum
which are non electives like drives and some more included in the main curriculum involving
the new generation of microcontrollers. The students can be made aware of the projects being
done by the trainees of the other industries so that they get a wider perspective .

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CHAPTER 9

APPENDIX

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9. APPENDIX
9.1 ALGORITHM
START

INPUT TO CURRENT SENSOR

FROM BATTERY

VALUE OF
YES CURRENT NO CB
CB GREATER REMAINS
OPEN THAN CLOSED
THRESHOLD
VALUE

ISOLATOR ISOLATOR
OPEN REMAINS
CLOSED

EARTHING EARTHING
SWITCH SWITCH
CLOSE REMAINS
OPEN
END

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9.2 ACTUAL PROGRAM
#include <Blynk.h>

#include <BlynkSimpleEsp8266.h>

float current ;

char check ;

// You should get Auth Token in the Blynk App.

// Go to the Project Settings (nut icon).

char auth[] = "dd33aac9c27942159e8e6e7b4d306e0c";

// Your WiFi credentials.

// Set password to "" for open networks.

char ssid[] = "Arjun's iPhone";

char pass[] = "ArjunIphone";

int i = 0;

void setup()

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{

//Blynk Configuration

Serial.begin(9600);

Blynk.begin(auth, ssid, pass);

//NodeMCU Pin Configuration

pinMode(D0, OUTPUT);

pinMode(D1, OUTPUT);

pinMode(D2, OUTPUT);

pinMode(D3, OUTPUT);

pinMode(D5, OUTPUT);

pinMode(D6, OUTPUT);

pinMode(D7, OUTPUT);

pinMode(A0, INPUT);

pinMode(LED_BUILTIN, OUTPUT);

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}

void loop()

{
Blynk.run() ;

int che = digitalRead(D7);

if(che == 0)

current = analogRead(A0) ;

Serial.print(current);

if(current <= 556)

underval() ;

if(current > 557)

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 {

overval () ;
}

else

Blynk.run() ;

void underval()

digitalWrite(D5, LOW);

digitalWrite(D3, LOW);

digitalWrite(D1, LOW);

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 digitalWrite(D6, HIGH);

delay(1000) ;

digitalWrite(D0, HIGH);

delay(1000) ;

digitalWrite(D2, HIGH);

delay(1000) ;

void overval()

digitalWrite(D2, LOW);

digitalWrite(D0, LOW);

digitalWrite(D6, LOW);

digitalWrite(D3, HIGH);

delay(1000) ;

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 digitalWrite(D1, HIGH);

delay(1000) ;

digitalWrite(D5, HIGH);

delay(1000) ;

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CHAPTER 10

REFERENCES

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10. REFERENCES
SIPROTEC

https://www.google.co.in/search?q=nodemcu+esp8266+12E&source=lnms&tbm=isch&sa=X
&ved=0ahUKEwjP-dO8qqDcAhXCXysKHVtLDI0Q_AUICigB#imgrc=k0M4tsGD26Cw1M:

https://w3.siemens.com/mcms/industrial-communication/en/rugged-
communication/technology-highlights/pages/iec-61850-protocol.aspx

http://blog.commscopetraining.com/how-do-wireless-networks-transmit-data/

https://www.google.co.in/search?safe=active&ei=U_LjWuTCHczbvATz16PQAQ&q=ge+mod
ular+sas&oq=ge+modular+sas&gs_l=psy-
ab.3..33i160k1l2.2070.6683.0.7775.14.12.0.2.2.0.203.1986.0j9j2.11.0....0...1c.1.64.psy-
ab..1.12.1792...0j35i39k1j0i67k1j0i131k1j0i131i67k1j0i10k1j0i22i30k1.0.IQLtysXVjF4

https://www.c-sharpcorner.com/article/blinking-led-by-esp-12e-nodemcu-v3-module-using-
arduinoide/

https://www.blynk.cc/

https://github.com/blynkkk/blynk-library/blob/master/examples/Boards_WiFi/NodeMCU/NodeMCU.ino

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