Japan International Cooperation Agency

National Power Transmission Network

Development Project
in Myanmar
(Power Network System Plan)

Site Investigation Report

May 2015
Tokyo Electric Power Company Inc.
The First Site Investigation Report
1. Name of Experts, Belonging Organization and His Duty
Masaharu Yogo, TEPCO, Power System Planner
2. Name of the Project
National Power Transmission Network Development Project in Myanmar
3. Purpose of This Investigation
Myanmar government cited the development of 500 kV transmission lines and substations
as a matter of priority and issued a request of their development by utilizing yen loan.
According to the request, the Japanese Government informed Myanmar government of a
new yen loan project as the donor policy on March 24, 2014 targeting “National Power
Transmission Network Development Project Phase 1” in Myanmar. Furthermore, following
the Phase 1, the rapid development of Phase 2 are also needed. In this survey, engaged
member will carry out the supplementary investigation in cooperation with his counterpart,
the Myanmar Electric Power Enterprise, in order to examine and recommend the
appropriate power system plan for preparation of yean loan project by collecting and
organizing the relevant information based on the current plans and implementation of the
transmission lines and substation projects by Myanmar Government, power generation
plans utilizing IPP and the support planning and implementation status of other donors.
4. Methodology
The latest information regarding Myanmar’s power system network plan was collected and
reviewed. The necessary investigations were carried out for contributing to prepare the
appraisal as yen loan projects relevant to the power network system plans in Myanmar in
cooperation with the environmental expert and JICA staff (F/F mission and appraisal
mission).
5. Duration of the Project Survey
From January 16th 2015 to May 29th 2015 (scheduled)
The first site investigation was from January 18th to 28th 2015.
6. The First Site Investigation
In January 19th, 20th and 22nd, the information was collected based on the questionnaire
attached in this report through the discussion with the Power Transmission Project
Department of MEPE and DEP. In 26th January, the mission team carried out the site
investigations at the candidate sites of Pharyargyi and Hlaingtayar to confirm their latest
situations regarding the Phase 2 Project. The confirmed information is described as
follows.

The First Site Investigation -1

A. The Situations of Land Acquisitions

(1) Phayargyi Substation (Figure 1)

The location of the candidate site of 500 kV Phayargyi Substation had been moved to the
outside of the military land by around 1 km in the south direction because the permission
for its land usage had not been given by the military. The new site is a plane land without
any hats or buildings, but with containing a wet land even in dry seasons. A distribution
line of 11 kV that supplies the power to the military crossed over the southern part of the
site from east to west. It is needed to be moved. (Its replacement cost is estimated around 2
or 3 million) The 500 kV switch yard will be installed in the north. The 230 kV switch
yard will be installed in the south where 6 circuits of 230 kV transmission lines will be
derived. The route of 500 kV transmission line between the original site of Pharyargyi and
Hlaingtayar was not changed from the previous plan in 2014. The 500 kV transmission
line between the new location and the original location is needed to be added. There are no
buildings around this route.

(2) Hlaingtayar Substation (Figure 2)

The land for the new 500 kV Hlaingtayar Substation was owned by seven households. The
six of them had been already paid for land provision, however, one of them would not
enter into negotiations with MEPE and it seemed difficult to negotiate him. Lacking of his
land would increase in the cost of substation because it requires compact facilities such as
Gas Insulated Switchgears (GIS). Thus, the new additional land acquisition neighbor to the
original land in the east direction was proposed and MEPE was expected to study its
adequacy. The candidate site is a plain land with only a small hut utilized agricultural
works. The 500 kV switch yard will be installed in the north and the 230 kV switch yard
will be installed in the south.

The First Site Investigation -2

 To Taungoo
Double circuit 500 kV
Transmission line

This original route already studied Former location of Phayargyi

(Result of 2014 study)

To Hlaingtayar
1.1 km
Military Land

New location of 500 kV

Phayargyi
230 kV

Proposed new additional 500 kV

transmission line

New location of 500 kV Phayargyi

substation

Switch Yard

Figure 1 New Location of 500 kV Phayargyi Substation

The First Site Investigation -3

 Around
300 m
500 kV

230 kV

Around
400 m

Land difficult to be negotiated

Proposed additional land to be negotiated

Land already acquired

Switch Yard

Figure 2 Land of Hlaingtaryar

The First Site Investigation -4

B. Confirmation of the Latest Plans of Power Generation, Transmission Lines and
Substation

(1) Power Demand Forecast and Power Generation Plan

The maximum electric power demand during the peak demand period of time (from March
to May) in 2015 was forecasted as 1,500 MW for Yangon and 2,500 MW for the system of
the whole country. From 2015, the yearly growing ratio of the maximum power demand is
expected over 15%. DEP expressed an opinion that the latest demand forecast was the
result of its study of the JICA Master Plan. The total generation capacity of Yangon city is
currently 370 MW and expected to become 800 MW at the end of 2015.

(2) Plan of 230 kV Transmission Lines and Substations in Yangon

MEPE planned 230 kV transmission lines and substations in Yangon as shown in the
following table.

Table 1 Project Plan for Yangon Division

No. Name of Projects Expected Fund
1. 230kV Ahlone-Thidar Transmission Line & Substation China Exim Bank
2. 230 kV Tharkata-Kytekasan Transmission Line & Substation ADB
3. 230 kV Tharkata -Thidar Transmission Line
4. 230 kV Ahlone Dala Transmission Line & Substation MEPE
5. 230 kV (Hlawga-Tharketa) In/Out Transmission Line & Sorth MEPE
Oakkalar Substation
6. 230 kV (Hlawga-Tharketa) In/Out Transmission Line & North MEPE
Oakkalar Substation
7. 230/66/11 kV, (2x125)MVA Bayintnaung Substation Extension Deferred
8. 66 kV East Dagon- Shwe Pauk Kan Transmission Line Deferred
9. 66 kV East Dagon-Wai Bar Gee Transmission Line Deferred
10. 66 kV East Shwe Pauk Kan- North Oakkalar Transmission Line Deferred
11. 66 kV East Dagon-Kon Padathar Transmission Line Deferred
12. 66 kV East Dagon-East Dagon (1)(2) Transmission Line Deferred
13. 66/33 kV, (30)MVA & 66/11 kV, (2x25)MVA Shwe Pauk Kan Deferred
Substation
14. 66/11 kV, (2x25)MVA North Oakkalar Substation Deferred
15. 66/11 kV, (2x25)MVA Wai Bar Gee Substation Deferred

The First Site Investigation -5

 The comments raised for the abovementioned list was as follows.
- All the projects were under discussion in the similar situation as “National Power
Transmission Network Development Project Phase 2”. However, MEPE hoped to
complete all the project within two years. That was expected to be completed by the
end of 2018.
- The 230 kV Ahlone-Dala transmission line listed in the number 4 probably to be
carried out using its own funds of MEPE because the length of this transmission line
was very short.
- Bayintnaung substation listed in 7 was expected to be completed in 2017 because this
project contained just the expansion of substation.
- The projects of “Deferred” were still opened to the tenders.

The following comments were raised for the Project that were not listed in Table 1.
- The completion year was uncertain of 500 kV Phayargyi – Dawei transmission line
because it depended on the plan of the Dawei power station.
- Shweli 3 was scheduled to be completed in 2020. There was an enterprise company
that expressed an interest in the installation of 500 kV transmission line from Shweli 3
to Methila and said that he might implemented.
- The survey of the transmission line from Mawlamyine to Dawei has been asked to
China Exim Bank. Dawei would have large power demand forecast due to its SEZ.
- The expected completion date of the transmission line between Taungoo and
Pharyargyi would be informed as much as possible because its completion date
seemed to be important information for JICA Project.

(3) Transmission Lines connected to New 500 kV Substations of Phase 2 Project just after
Their Completion
There were no changes from the results of the study in 2014 of the transmission line
connection to new 500 kV substations of Phase 2 Project. The followings were
scheduled.。

The First Site Investigation -6

 Table 2 The Number of Circuits of Transmission Lines Connected to New 500 kV
Substations at Their Initial Operation
500 kV Bus Connected Transmission Line Number Number
substation voltage of of
Circuits circuits
at bus
bars
Pharyargyi 500kV 500 kV Transmission Line to Taungoo 2 6
500 kV Transmission Line to Dawei 2
500 kV Transmission Line to Hlaingtayar 2
230 kV Line in-out to 230 kV Tharyargone - Kamarnat 4 6
230 kV Transmission Line to East Dagon 2
Hlaingtayar 500kV 500 kV Transmission Line to Ngayotekaung 2 4
500 kV Transmission Line to Pharyargyi 2
230 kV Line in-out to 230 kV Hlaingtayar-Ywama 4 6
Line in-out to Myauntagar-230 kV Hlaingtayar 2

(4) Main Specifications of Phase 2

The mission team had discussions with Power Transmission Project Department of MEPE
regarding the main specifications of Phase 2 Project (Attached as reference of
questionnaire) based on the previous study in 2014.
No main specifications had been changed except for pollution level of Insulators.
- MEPE hoped to apply the heavy pollution level to the route around 4 to 5 km before
reaching 500 kV Hlaingtayar substation. On the other hand, the light pollution level
was recommended to be applied for the whole of the transmission line routes by JICA
team side based on the site survey in the 2014 previous study and this study. The
applied pollution levels should be discussed with MEPE during the detailed design
stage.
- MEPE raised a comment that they hoped to know the O&M methodology for Oil
Forced Cooling System to maintain its better insulation. (Some know-hows are
considered such as Dessolved Gas Analysis and Reduce Oil Circulator Speed )

(5) Prioritized Projects of Transmission Lines and Substations Except for the System
from 500 kV Taugoo – Hlaingtayar
MEPE identified the study of the plan of the transmission lines from the hydropower
stations located in the north of Meiktila substation as the prioritized projects.

(6) Institutional Structure for O&M

Currently, there are fourteen Transmission Line Offices with 137 staffs per office on the
average. One office maintains 700 – 800 km of lines by 30-40 persons. Safety trainings are

The First Site Investigation -7

 held by Administration Office.

C. Power Flow Analysis for the 500 kV System of Phase 2 and 230 kV System in around
Yangon

(1) 500kV and 230kV System in around Yangon

Figure 3 shows the plan of the 500 kV and 230 kV power network system in around
Yangon around 2020 after Phase 2 500 kV Project will be completed based on the
information from MEPE.
The 230 kV system of Yangon will be divided into east and west, where eastern system
will have Hlawga, East Dagon, Thaketa and Thanlyin and western system will have
Hlaingtayar, Ywama, Bayintnaun and Ahlone. There will be no direct interconnection of
230 kV between them.
Two 500 MVA transformers of 500/230 kV will be installed in Phayargyi and Hlaingtayar
respectively.

The First Site Investigation -8

 Power Plant Being planned
TAUNGOO
Substation PhaseII Project
500 kV transmission line
230 kV transmission line

PHAYARGYI DAWEI

JICA
KAMARNAT

MYAUNTAGAR

HLAWGA

HLAINGTAYAR 500kV

N. OAKKALAR
NGAYOTEKAUNG E. DAGONG
6.
HLAINGTAYAR 5.
YWAMA
S. OAKKALALAR
7.
BAYINTNAUNG
2.
THAKETA
KYAIKASAN
AHLONE
3.

THIDA
1. THANLYIN
KYAIKLATT
4.
JICA
PWH Thailand DALA
TILAWA

Figure 3 500 kV and 230 kV System in around Yangon around 2020

The First Site Investigation -9

(2) Load Forecast for 230 kV Substati ons in Yangon in 2020
The maximum power demand of Yangon in 2020 was set out as 2,869 MW from the result
of JICA Master Plan Study. The insufficient energy will be taken from the outside of this
area at Myauntagar, Payargyi and Kamarnat substations and the amount of its required
energy will be determined only by the power demand supply balance in Yangon. The power
generation plan outside of Yangon was used as the plan obtained in the study in 2014. Loads
of 230 kV substations in Yangon were set out as follows.
・ There are two ways of power supply from 230 kV substations, one is by 66 kV and
another is 33 kV. Thus, the amount of loads of 230 kV substations has to be divided
into loads of 66 kV system and 33 kV system. The maximum power demand in 2014
was 917 MW in Yangon. Around 40% (372 MW) was allocated to 66 kV system and
around 60% (545 MW) was allocated to 33 kV system based on the current power
supply information.
・ The growing ratio of the maximum power demand in Yangon was assumed 20% per
year for the first 5 years and 10% for the next 5 years and the growing ration of the
maximum power demand of 33 kV system was assumed only 4% because the loads of
33 kV system were planned to be gradually switched to 66 kV based on the
information obtained from YESB last year. This maximum power demand can be
depicted as shown in Figure 7 that lies at the middle point between the high case and
the low case in 2020 estimated in JICA Master Plan. The high case maximum power
demand of JICA Master Plan was applied as the maximum power demand of this study
for 2020.

4500

4000

3500
MP High
3000
33kV Load
2500 66kV load
MP Low Total
2000

1500

1000

500

0
2012 2014 2016 2018 2020 2022 2024 2026

Figure 4 Maximum Power Demand Forecast in Yangon

The First Site Investigation -10

・ The ratio of the allocated load of 66 kV system was 72.5 % and 33kV system was
27.5%. Using those ratios, the maximum power demand of 66 kV system was
calculated as around 2,081 MW and 33 kV was around 788 MW for 2020 based on the
high case demand of JICA Master Plan, 2,869 MW in 2020.
・ The capacities of the facilities of 230 kV substations in Yangon in 2020 were estimated
as shown in the following table. The information about the expansion of Ahlone,
Thakheta, Thanlyin and Iwama was obtained at the end of 2014. It was found out that
the 66 kV system could have around 2,200 MW and the 33 kV system around 1,300
MW according to the following table assuming 90% as the power factor of
transformers and 80% as the power supply ability ratio to the capacities of the
transformers and generators.

Table 3 Capacities of Facilities at 230/66 kV Substations

Estimated
66 kV Power Existing
230/66 kV Substation Capacities After
Supply Facilities Capacities
Expansion
66 kV Gen. 194 MW
Ahlone
230/66 kV Trans. 2 x 100 MVA 3 x 100 MVA
Bayintnaung 230/66 kV Trans. 100 MVA 2 x 125 MVA
Hlawga 230/66 kV Trans. 60 MVA
66 kV Gen. 84 MW
Thakheta
230/66 kV Trans. 2 x 100 MVA 3 x 100 MVA
66 kV Gen. 50 MW
Iwama
230/66 kV Trans. - 2 x 125 MVA
East Dagong 230/66 kV Trans. - 2 x 125 MVA
South Okkalapa 230/66 kV Trans. - 2 x 125 MVA
Kyaikkasan 230/66 kV Trans. - 2 x 125 MVA
Thida 230/6 6kV Trans. - 2 x 125 MVA
66 kV Gen. 50 MW
Tilawa
230/66 kV Trans. - 2 x 100 MVA

The First Site Investigation -11

 Table 4 Capacities of Facilities at 230/33 kV Substations
Estimated
33 kV Power Existing
230/33 kV Substation Capacities After
Supply Facilities Capacities
Expansion
66/33 kV Trans. 60 MVA
Ahlone
33 kV Gen. 100 MVA
Hlaingtharyar 230/33 kV Trans. 2 x 100 MVA
230/33 kV Trans. 3 x 100MVA
Hlawga
33 kV Gen. 210 MVA
Thanlyin 230/33 kV Trans. 100 MVA 2 x 100 MVA
Wartayar 230/33 kV Trans. 100 MVA
230/33 kV Trans. 100 MVA
Thakheta
33 kV Gen. 50 MVA
Iwama 33 kV Gen. 36 MVA
West University 230/33 kV Trans. 2 x 100 MVA

・ The maximum load of around 2,081 MW for 66 kV system and the maximum load of
around 788 MW for 33 kV system were assumed to be supplied from 230 kV
substations in proportion to their power supply capacities. The estimated loads of 230
kV substations were listed as Table 4.

Table 5 Maximum Power Demand Forecast for 230 kV Substations in 2020

66 kV Load (MW) 33 kV Load (MW)

Ahlone 391 Ahlone 84

Bayintnaung 189 Hlaingtharyar 99

Hlawga 45 Hlawga 263

Thakheta 298 Thanlyin 99

Iwama 231 Wartayar 49

East Dagong 189 Thakheta1 38

South Okkalapa 189 Thakheta2 38

Kyaikkasan 189 Iwama 20

Thida 189 West University 99

Tilawa 168 Total 788

Total 2,081

The First Site Investigation -12

(3) The Result of Power Flow Calculation of the 500 kV and 230 kV System in around
Yangon around 2020 (Base Case)
Figure 5 shows the result of power flow calculation for the base case of 500 kV and 230 kV
system in around Yangon around 2020 with modeling the original plan by MEPE.
The power flows in the interval of 230 kV transmission lines such as Myauntagar –Hlawga
and Hlaingtayar-Ahlone - Thida - Thakheta largely exceed their capacities causing
overloaded situations. Thus, some countermeasures will be required.

The following two types of conductors are mainly used for 230 kV transmission lines in
Myanmar.
Twin bundle conductors of 605 MCM, its capacity is 288 MVA/cct
Single conductor of 795 MCM and its capacity is 164 MVA/cct
The single of 795 MCM is used for Tharyargone - Hlawga that has a smaller capacity and
the twin bundles of 605 MCM is mainly used for other interval.

The power generators in around Yangon area were set out as shown in Table 5. The
numerical values of power outputs from Thaketa, Ahlone, Ywama and Hlawga were used
that were also used in the previous study.

Table 5 Power Outputs of Generators in around Yangon Area in Base Case

Power Stations In service Out of service
Tilawa 50 MW 0 MW
Thakheta 92.2 MW 0 MW
Ahlone 278.4 MW 0 MW
Ywama 223.5 MW 0 MW
Hlawga 104.7 MW 51.1 MW
TWH Thailand 500 MW 0 MW
Ngayotekaung 540 MW 0 MW
Dawei 450 MW 0 MW

This case can be considered as the case with large power outputs of generators in around
Yangon area.

The First Site Investigation -13

 THARYARGONE
Power Plant TAUNGOO
Substation
450
500 kV transmission line 535

230 kV transmission line

687
PHAYARGYI DAWEI

400

27 155

MYAUNTAGAR 292

125
93 KAMARNAT

434

320
*** 常 時 過 負 荷 潮 流
203
HLAWGA
56
HLAINGTAYAR 500kV 172
540 229
830
11 N. OAKKALAR
NGAYOTEKAUNG E. DAGONG
55
220
HLAINGTAYAR 118 252
396 YWAMA
S. OAKKALALAR
106 174 THAKETA
BAYINTNAUNG

415 KYAIKASAN
AHLONE
58
358
THIDA
THANLYIN

534
195 104
KYAIKLATT
DALA

306 TILAWA

Blue colored figures indicates over loaded power flow (MW)

Myauntagar – Hlaingtayar, Myauntagar –Hlawga, Hlawga- N. OAKKALAR, Phayargyi – East Dagon etc. Over
Loaded
Figure 5 Power Flow of Base Case in 2020

The First Site Investigation -14

(4) Option of 230 kV Interconnection between East and West in Yangon around 2020
An option of the installation of the 230 kV transmission lines connecting the east and west in
Yangon (they may be installed with underground cables due to their locations in a city area) is
studied as a countermeasure against overloaded situations in Base Case.
The result of the calculation is shown in the following figure. Blue colored lines indicate newly
installed transmission lines. There are no overloaded 230 kV transmission lines in normal
operation. This option assumes the installation of a single circuit between 230 kV Hlaingtayar
and Bayintnaung and double circuits between Ywama and South Okkalar.

The First Site Investigation -15

 THARYARGONE
Power Plant TAUNGOO
Substation
450
500 kV transmission line 555

230 kV transmission line

551
PHAYARGYI DAWEI

360

15 124

MYAUNTAGAR
110 449
102 KAMARNAT

342

106

5
HLAWGA
56
HLAINGTAYAR 500kV 123
540 11
986
N. OAKKALAR
NGAYOTEKAUNG 419 E. DAGONG
222
201
HLAINGTAYAR 443 49 125
360 YWAMA
309
88 S. OAKKALALAR
135 THAKETA
483BAYINTNAUNG

108 KYAIKASAN
AHLONE
95
18
THIDA
THANLYIN
192

232 104
KYAIKLATT
DALA

264 TILAWA

Figure 6 Power Flow in the 230 kV System with East-West Interconnection

The First Site Investigation -16

(5) Option of the Future System Configuration of Fulfilling N-1 Criteria
The options of the installation of the 230 kV Interconnection between east and west does not
caused overloaded situations in normal operation; however, the overloads are caused by
dropping a single circuit of 230 kV or a 500 kV transformer.
An option of the installation of both the 230 kV Interconnection between east and west in
Yangon and the eastern 500 kV substation around Yangon does not cause overloaded situations
even when a 230 kV single circuit is dropped. The loads of 500 kV transformers can be within
120 % of their capacity even when one of their banks is dropped in this option.
Those cases are the cases with large power outputs of generation in around Yangon. The severe
cases should be studied such as the cases with lower power outputs of generators in Yangon.

The First Site Investigation -17

 Power Plant THARYARGONE
Substation with transformers to its lower side TAUNGOO

Switch yard 617

Being planned 450

500 kV transmission line
230 kV transmission line PhaseII Project
338
PHAYARGYI DAWEI

160 285

MYAUNTAGAR 100

6 71 KAMARNAT
81
Power flows in ( ) indicate
the case of a single circuit 80
fault or a single bank fault

55
564
HLAWGA
16 49

HLAINGTAYAR 500kV
698 E. DAGONG
540
(492) 563
51 (393)
NGAYOTEKAUNG
202
136 175
HLAINGTAYAR 219 359(252)
245 YWAMA

94 S. OAKKALALAR
336 (267) KYAIKASAN
BAYINTNAUNG 153 THAKETA

146
85 44
AHLONE 139
45
THIDA
THANLYIN
144

239 118
261
KYAIKLATT
DALA
TILAWA

( ): power flow in case of dropping a single circuit fault or a transformer

Figure 7 Power Flow in the Future System Fulfilling N-1 Criteria

The First Site Investigation -18

(6) Cases without Phase 2 Project
The power flow was calculated in case of not implementing Phase 2 Project for the case with
the 230 kV east – west interconnections (the case of relatively large power outputs of generators
in around Yangon). Ngayotekaung and Dawei thermal power stations were assumed to be still
connected to 500 kV transmission lines because they were independent from Phase 2 Project.
This case assumed that Phase 1 and the transmission line from Meikhtila to Pharyargyi through
Taungoo were implemented.
From the result of the power flow analysis, the power flows at Tharyargone - Hlawga and East
Dagone-Thaketa exceeded the capacities of their lines apart from Hlaingtayar - Ahlon and
Kyaiklat-Ahlon if Phase 2 was not implemented.

The First Site Investigation -19

 THARYARGONE
Power Plant
267
Substation
450
500 kV transmission line
230 kV transmission line

PHAYARGYI DAWEI

447

11 182

MYAUNTAGAR
96 557
138 KAMARNAT

247

182

119
HLAWGA
56
HLAINGTAYAR 500kV 172
540 119
N. OAKKALAR
NGAYOTEKAUNG 267 E. DAGONG
201
139
HLAINGTAYAR 256 27 270
250 YWAMA
211
S. OAKKALALAR
93
37 THAKETA
385BAYINTNAUNG

118 KYAIKASAN
AHLONE
28 47
THIDA
THANLYIN
202

234 104
KYAIKLATT
DALA

266 TILAWA

Figure 8 Power Flow in Case of Not Implementing Phase 2 Project for B the case with the
230 kV east – west interconnections in 2020

The First Site Investigation -20

(7) Power Flow in Case of Lower Power Outputs from Thermal Power Stations in 2020
(Power output from Ngayotekaug in the west is zero)

The power flow would be increased from the northern area where a lot of hydropower stations
will be located to Yangon in case of the lower power outputs from the thermal power stations in
Yangon. The power flow was calculated for the both cases with and without Phase 2 setting out
no power outputs from Ngayotekaug power station located in the west of Yangon. The power
outputs were set out as follows.

Table 6 Power Outputs of Generators in around Yagon in Case of Lower Power Outputs
from Thermal Power Stations in 2020 (Power output from Ngayotekaug in the west is
zero)
Power Station Power Outputs Stopped Power Outputs
Tilawa 50 MW 0 MW
Thakheta 92.2 MW 0 MW
Ahlone 278.4 MW 0 MW
Ywama 223.5 MW 0 MW
Hlawga 104.7 MW 51.1 MW
TWH Thailand 500 MW 0 MW
Ngayotekaung 0 MW 540 MW
Dawei 450 MW 0 MW

Figure 10 shows the power flow with Phase 2 in this generation pattern.
In the similar manner to the base case, the power flows between Hlaingtayar - Ahlon and
Kyaiklat – Ahlon exceed their capacity of transmission lines. There are some intervals of
230 kV transmission lines that have the over loading power flow in case of a fault of a
circuit around Hlawga, East Dagon and Ahlone.
Without Phase 2, the power flow calculation was not converged. This means that the power
transmission is not possible at the maximum power demand without Phase 2. Its calculation
was converged when the maximum power demand was decreased.The power flow became
not to exceed the capacities of the transmission lines when the power demand of Yangon
was decreased by around 28%. The Figure 11 shows the results of the power flow
calculation for this case.

The First Site Investigation -21

 Power Plant TAUNGOO 193
Substation
450
500 kV transmission line 968

230 kV transmission line

534
PHAYARGYI DAWEI

367

30 139

MYAUNTAGAR 874

161 100 KAMARNAT

358

131

32
HLAWGA
56
HLAINGTAYAR 500kV 132
0 29
871
N. OAKKALAR
NGAYOTEKAUNG 380 E. DAGONG
223
187
HLAINGTAYAR 268 49 179
335 YWAMA
291
S. OAKKALALAR
74 465 117
BAYINTNAUNG THAKETA

103 KYAIKASAN
AHLONE
87
11
THIDA
THANLYIN
185

236 104
KYAIKLATT
DALA

264 TILAWA

Figure 9 Case of Lower Power Outputs from Thermal Power Stations in 2020 (Power
output from Ngayotekaug in the west is zero)

The First Site Investigation -22

 Power Plant TAUNGOO 258
Substation
450
500 kV transmission line
230 kV transmission line
473
PHAYARGYI DAWEI

363

42 159

MYAUNTAGAR
205
104 KAMARNAT

338

123

115
HLAWGA
41
HLAINGTAYAR 500kV 124
0 135
N. OAKKALAR
NGAYOTEKAUNG 52 E. DAGONG
116
22
9
HLAINGTAYAR 107 208
40 YWAMA
73
S. OAKKALALAR
59 198 52 THAKETA
BAYINTNAUNG

27 KYAIKASAN
AHLONE
20
41
THIDA
THANLYIN
166

254 61
KYAIKLATT
DALA

246 TILAWA

Figure 10 Case of Lower Power Outputs from Thermal Power Stations in 2020 (Power
output from Ngayotekaug in the west is zero) without Phase 2 Decreasing Power Demand
of Yangon by 28%

The First Site Investigation -23

(8) The Future 500 kV and 230 kV System Configuration in Yangon
When the maximum power demand of Yangon will reach 4,000 MW from 2,869 MW that is the
maximum power demand of Yangon in 2020, it is considered that more four substation at least
will be required even in consideration with the expansion of the existing substations. The
installation of the east-west interconnections and the east 500 kV substation are both considered
as the effective countermeasures against overloaded conditions. An option of the future 500 kV
and 230 kV system in Yangon is shown in the following figure.

The First Site Investigation -24

 THARYARGONE
Power Plant TAUNGOO
Substation
500 kV transmission line
230 kV transmission line

PHAYARGYI DAWEI

MYAUNTAGAR

KAMARNAT

HLAWGA

HLAINGTAYAR 500kV
E. DAGONG

N. OAKKALAR
NGAYOTEKAUNG

HLAINGTAYAR
YWAMA
S. OAKKALALAR
KYAIKASAN
BAYINTNAUNG THAKETA

AHLONE

THIDA
THANLYIN

KYAIKLATT
DALA
TILAWA

Figure 11 Option of the Future 500 kV and 230 kV System in Yangon

The First Site Investigation -25

(9) Recommendations for Future Power System Configuration
The followings can be raised as the candidates of recommendations for future power
system configuration.

Implementation of 500 kV and 230 kV transmission lines and substations planned by

MEPE including Phase 2 Project on schedule
Installation of 230 kV transmission lines connecting the east and the west in Yangon
through Ywama-S.Oakkalar and Bayintnaung-Kyaikasan and doubling circuits of
Hlaigntayar-Bayintnaung and Thaketa-Kyaikasan up to around 2020. It will contribute to
secure the power supply to the substations planed by MEPE responding to the rapid
growing of power flow from the west to the east in Yangon.
Installation of the new 500 kV substation in the eastern part of Yangon in around East
Dagon to supply power from the east. In order to prepare this, the transmission line from
Pharyargi to East Dagon is considered to be constructed as 500 kV design lines.

Abovementioned recommendations would be required even for the situations where power
outputs from generators in around Yangon are relatively large. However, the detailed
studies will be required including the fault current analysis regarding the bulk power
system in Yangon because the system power flow can be changed in accordance with the
power generation plans and their operation.

In future, some 230 kV substations will be required apart from the current plan. Those
substations will be connected to east and west in Yangon respectively.

The First Site Investigation -26

 <Appendix 1>

Questionnaire for the Counterparts during the First

Site Survey

The First Site Investigation -27

 Questionnaire (Power System Plan)
JICA 500 kV Phase 2
2015/01/19
M. YOGO, TEPCO
JICA Mission

Purpose of this Study

To carry out the supplementary survey to prepare the JICA appraisal mission of 500 kV Phase II
Project by examining and recommending the adequate system plan through reviews of the latest
information.

Questionnaire (Power System Plan)

1. The latest nationwide power demand forecast (Maximum power as MW) (also the latest
power demand forecast in Yangon)
2. The latest power generation plan and its on-going projects including their expected
donors (also the latest power generation plan in around Yangon)
3. The latest bulk power transmission line/substation plan and its on-going projects
including their expected donors (also the latest 230 kV power transmission
line/substation plan in around Yangon))
4. The prioritized projects except for 500 kV Phase II
5. Current situations and their main specifications of 500 kV Phase II
6. Any significant changes in the route of 500 kV Hpharyargyi - Hlainghtaryar
transmission line from the Previous Study?
7. Are there any significant changes in the location of 500 kV Hpharyargyi and
Hlainghtaryar substations from the Previous Study?
8. Are there any significant changes in the main specifications of 500 kV transmission line
from the Previous Study?
9. Are there any significant changes in the main specifications of 500 kV Hpharyargyi and
Hlainghtaryar substations from the Previous Study?
10. Expected institutional arrangement for O&M
11. Current progress and main specifications of Meikhtila-Taungoo –Pharyargyi 500 kV
transmission lines

JICA 500 kV Phase II Project means “500 kV Phatyargyi and Hleigntayar substation and
their connecting 500 kV transmission line”.
Previous Study means “JICA Expert for Strengthening of Implementation Capacity for
Transmission Line and Substation, 2014”.

The First Site Investigation -i

<Reference>
Main Specifications of the Phase II Project

500 kV Hpharyargyi - Hlainghtaryar transmission line

Conductor: Drake four (4) bundles
Pollution level “Light”
Insulators made in Japan
Clearances are same as 500 kV Meikhtila – Taungoo Transmission line

500 kV Hpharyargyi substation and 500 kV Hlainghtaryar substation

Number of Feeders, Transformers and Reactors
Hpayargyi Hlaingtharyar
6 4
Number of 500 kV Taungoo: 2, Hlaingtharyar: 2, Hpayargyi: 2, West Yangon:
Line feeders Dawei: 2 2
(Final 8) (Final 8)
6 6
Number of 230 kV Line Tharyargone: 2, Kamarnat: 2, Myaungtagar: 1, Ywama: 2,
feeders Dagon East: 2 Hlaingtharyar: 3
(Final 12) (Final 12)
Number of 500/230/11 2 2
kV Transformer banks (Final 4) (Final 4)
Reserved transformer
1 1
(Single Phase)
2 2
Reactor (100 MVA)
(Final 4) (Final 4)
Specifications of the 500/230/11 kV Transformers
Type Outdoor type single phase Auto transformer
Capacity 500/3MVA/500/3MVA/75/3MVA
Shipping Mass Less than 60t (Actual limit weight should be studied in the Detailed
Design stage, Site-assembly type would be recommended.)
%Impedance 12.5% (P-S)
Tap ±50 kV 21 tap
Cooling system OFAF (Oil Forced Air Forced)
Specification of the 500 kV Reactor
Type Outdoor type single phase
Capacity 100/3MVA
Cooling system ONAN (Oil Natural Air Natural)
Shipping Mass Less than 60t(Actual limit weight should be studied in the Detailed
Design stage)
Connected Bus bar

The First Site Investigation -ii

 Telecommunication
Media Object Notes
OPGW PCM current differential relay for transmission line
protection
SCADA for National Control Center
High speed communication line in MEPE For Intranet, VoIP
PLC SCADA for National Control Center For Backup
Internal telephone line in MEPE
Circuit Breaker
500 kV H-GIS50 kA 50 kA
220 kV Gas Circuit Breaker 40 kA
Protection relay system
500 kV Line Main Digital PCM current differential relay with high speed
multi-phase re-closing relay system
Back-up Distance Relay (2-4 stage)
230 kV line Main Digital PCM current differential relay with high speed
re-closing relay system
Back-up Distance Relay (2-4 stage)
500 kV and 230 Current differential relay
kV bus
Transformer Main Ratio Differential Relay, OCR, OCGR (Neutral Protection)
Back-up Distance Relay (2-4 stage)
500 kV Reactor Ratio Differential Relay, OCR, OCGR (Neutral Protection)
The selection of seismic design standards applied to the 500 kV transmission system in
Myanmar should be discussed in the detailed design stage.
SCS (Substation Control System) of each substation will be connected to the National
Control Center (NCC) for the supervision and monitoring done by

The First Site Investigation -iii

The Second Site Investigation Report
1. Name of Experts, Belonging Organization and His Duty
Masaharu Yogo, TEPCO, Power System Planner

2. Name of the Project

National Power Transmission Network Development Project in Myanmar

3. Purpose of this Investigation

Myanmar government cited the development of 500 kV transmission lines and substations
as a matter of priority and issued a request of their development by utilizing yen loan.
According to the request, the Japanese Government informed Myanmar government of a
new yen loan project as the donor policy on March 24, 2014 targeting “National Power
Transmission Network Development Project Phase 1” in Myanmar. Furthermore,
following the Phase 1, the rapid development of Phase 2 are also needed. In this survey,
engaged member will carry out the supplementary investigation in cooperation with his
counterpart, the Myanmar Electric Power Enterprise, in order to examine and recommend
the appropriate power system plan for preparation of yean loan project by collecting and
organizing the relevant information based on the current plans and implementation of the
transmission lines and substation projects by Myanmar Government, power generation
plans utilizing IPP and the support planning and implementation status of other donors.

4. Methodology
The latest information regarding Myanmar’s power system network plan was collected and
reviewed. The necessary investigations were carried out for contributing to prepare the
appraisal as yen loan projects relevant to the power network system plans in Myanmar in
cooperation with the environmental expert and JICA staff (F/F mission and appraisal
mission).

5. Duration of the Project Survey

From January 16th 2015 to May 29th 2015 (scheduled)
The first site investigation was from January 18th to 28th 2015.
The second site investigation was from March 16th to 21st 2015

6. Contents of the Second Site Survey

The cost of the transmission lines was discussed with MEPE Engineer and the expert
explained the draft plan of power network system plan. The confirmed information is
described as follows.

The Second Site Investigation -1

7. Power System Plan
The team explained the 230 kV system plan in Yangon by using the attached material
(Power System Analysis for 230 kV System in Yangon) to MEPE Executive Engineer on
2015/3/18. He mentioned that the plan would be explained to DM and MEPE.

(1) The Revision of the List of the Plan of 230 kV System in Yangon
MEPE revised the list of the plan of 230 kV system in Yangon that was obtained during
the first site investigation.
- 230 kV (Hlawga-Tharketa) In/Out Transmission Line & North Oakkalar Substation was
canceled.
- Projects of 66 kV were deleted from the list and only the 230 kV projects were described.

(2) Reviewing ADB’s Report (by Fichtner)

The ADB’s report “ADB - TA 8342 MYA Preparing the Power Transmission and
Distribution Improvement Project” (Fichtner, Feb.2015) has been reviewed unofficially by
the mission team (not through MEPE).
The demand forecast of ADB’s Report was a little bit lower than that of JICA Master Plan
as follows.

The maximum demand for the whole system in ADB’s Report

Year 2020: 3,728 MW, Year 2030：7,498 MW

The maximum demand for the whole system in JICA Master Plan
Year 2020: High Case 4,531 MW, Low Case 3,862 MW
Year 2030: High Case 14,542 MW, Low Case 9,100 MW

The following projects in around Yangon were recommended in the ADB’s report.
Thida - Thaketa TL、Thaketa SS (extension)、Thaketa - Kyaikasan、Kyaikasan SS (new)、
South Oakkalarpa SS (new)、West University SS (new)

The 230/33kV West University Substation, that is listed above, was not informed in Table
1. However, this substation would have an effect on the Phase 2 Project because the ADB
report described this substation was to be installed at the same location of 500 kV
Hlaingtayar substation of Phase 2. JICA mission team had a discussion with MEPE
regarding this substation.

(3) 230/33kV West University Substation

MEPE informed that The 230/33 kV West University Substation was planned to be
The Second Site Investigation -2
 installed at the same land as the candidate site of the 500 kV Hlaingtayar Substation and
the bus bars of 230/33 kV West University Substation would be expanded and connected
to the 500 kV Hlaingtyar substation. Its implementation schedule was not yet decided.

(4) 230 kV Transmission Lines connected to 500 kV Pharyargyi and Hlaingtayar

Substations of Phase 2 Project just after Their Completion
Current status of the progress of 230 kV transmission line connection to 500 kV
substations were collected.
500 kV Phatryargyi Substation
In 2019, the 500 kV Pharyargyi substation will be connected to the newly constructed 230
kV transmission line between Tharyargone – Kamarnat where 500 kV Pharyargyi substation
is located in the middle of the line. The transmission line between Pharyargyi and East
Dagon was not yet decided, however, it would take normally only three years from its plan
to its operation in MEPE.
500 kV Hlaingtyar Substation
As mentioned later, 230/33 kV West University substation will be constructed in the same
location as 500 kV Hlaingtayar Substation by ADB. 230/33 kV West University substation
will collect the existing transmission line from Mayungtagar - 230 kV Hleingtayar. 500 kV
Hlaingtayar Substation will be installed as the expanded substation of 230/33 kV West
University.

(5) The Connection of 500 kV Hlaingtayar Substation to 230/33kV West University

Substation
Points to note regarding the connection of the 230/33 kV West University Substation and
the 500 kV Hlaingtayar Substation are as follows.
(The design of both projects should be coordinated regarding the methodology of the
expansion of 230/33 kV West University Substation to 500 kV Hlaingtayar substation at the
detailed design stage.)

The layout of the facilities of the foregoing ADB 230 kV West Univrsity substation should
be necessarily incorporated with the future layout of Phase 2 500 kV Hlaingtayar
Substation.
It is necessary to study the treatment of the protection relays and supervisory control
system of the foregoing ADB 230 k West University Substation when Phase 2 500 kV
Hlaingtayar substation will be installed. Generally, it is not enough for connection of bus
bars not only by the connection of bus bars itself. It also requires for changing the
connection of the information-telecommunication system utilized for supervisory control
system in the substation. (such as the selection of the locations of control rooms for both
The Second Site Investigation -3
old and new substations or the selection of the protection scheme against bus fault)
In case of difficulties, an option can be considered that connects new and old buses by
installation of the circuit breakers between them to ensure their independent operation as
shown in the following figure.

The Second Site Investigation -4

 Construction work area
500 kV
Circuit breakers

Circuit breakers at the 500/230 kV

connection point transformers
230 kV Lines

230 kV

230/33 kV transformers

230/33 kV 500/230 kV
West University Substation Hlaingtayar Substation

Figure 1 Covering areas of 230/33 kV West University Substation and 500/230 kV

Hlaingtayar Substation

(6) Revision of the List of the Projects of 230 kV System in Yangon

The list of the projects of 230 kV system in Yangon was revised based on the information
obtained during the second site investigation mentioned above.

Table 1 Project Plan for Yangon Division

No. Name of Projects Expected Fund
1. 230kV Ahlone-Thidar Transmission Line & Substation China Exim Bank
2. 230 kV Tharkata-Kyaikasan Transmission Line & Substation ADB
3. 230 kV Tharkata -Thidar Transmission Line ADB
4. 230 kV Ahlone Dala Transmission Line & Substation MEPE
5. 230 kV (Hlawga-Tharketa) In/Out Transmission Line & South MEPE
Oakkalar Substation
6. 230/66/11 kV, (2x125)MVA Bayintnaung Substation Extension Deferred
7. 230/33 kV, (2x100)MVA West University Substation Deferred

（The number of circuits between Ahlone - Thidar was assumed two and Thidar – Thaketa
single in this study according to the ADB’s Report “TA 8342 MYA Preparing the Power

The Second Site Investigation -5

 Transmission and Distribution Improvement Project” by Fichtner”. ）

The following two types of conductors are mainly used for 230 kV transmission lines in
Myanmar.
Twin bundle conductors of 605 MCM, its capacity is 288 MVA/cct
Single conductor of 795 MCM and its capacity is 164 MVA/cct
The single of 795 MCM is used for Tharyargone - Hlawga that has a smaller capacity and
the twin bundles of 605 MCM is mainly used for other interval.
The ADB’s Report that was mentioned in the previous section described the application of
ACCC (Aluminum Conductor Composite Core) for the interval of Thida – Thaketa. This
conductor can be used at high temperature with large capacity of 1,576 A (628 MVA) per
circuit. Thus, only this interval was assumed to be equipped with this conductor.
(However, the ADB’s report also mentioned that this conductor should not be applied for
other intervals because it would produce huge losses when the power flow reached closed to
its capacity.)

8. Power System Analysis

The power system analysis was carried out again based on the system described in the
report of the first site investigation and revised based on the information obtained during
the second site investigation.

(1) 500kV and 230kV System in around Yangon

Figure 3 shows the plan of 500 kV and 230 kV system in around Yangon around 2020 by
MEME when the 500 kV system of Phase 2 will be completed based on the information
from MEPE.

The Second Site Investigation -6

 Power Plant
TAUNGOO
Substation with transformers to its lower side
Switch yard
Being planned
500 kV transmission line
PhaseII Project PHAYARGYI
230 kV transmission line
DAWEI

KAMARNAT

MYAUNTAGAR

HLAWGA

HLAINGTAYAR 500kV

NGAYOTEKAUNG E. DAGONG
WEST UNIVERSITY

YWAMA
S. OAKKALALAR
HLAINGTAYAR
BAYINTNAUNG
THAKETA
KYAIKASAN
AHLONE

THIDA
THANLYIN

KYAIKLATT
DALA
TILAWA

Figure 3 500 kV and 230 kV System in around Yangon around 2020

(2) Load Forecast for 230 kV Substations in Yangon in 2020

The maximum power demand of Yangon in 2020 was set out as 2,869 MW from the result
The Second Site Investigation -7
of JICA Master Plan Study.
The maximum power demand of 66 kV system was assumed as around 2,081 MW and 33
kV was around 788 MW for 2020.
The capacities of the facilities of 230 kV substations in Yangon in 2020 were estimated as
shown in the following table.

Table 2 Capacities of Facilities at 230/66 kV Substations

Estimated
66 kV Power Existing
230/66 kV Substation Capacities After
Supply Facilities Capacities
Expansion
66 kV Gen. 194 MW
Ahlone
230/66 kV Trans. 2 x 100 MVA 3 x 100 MVA
Bayintnaung 230/66 kV Trans. 100 MVA 2 x 125 MVA
Hlawga 230/66 kV Trans. 60 MVA
66 kV Gen. 84 MW
Thakheta
230/66 kV Trans. 2 x 100 MVA 3 x 100 MVA
66 kV Gen. 50 MW
Iwama
230/66 kV Trans. - 2 x 125 MVA
East Dagong 230/66 kV Trans. - 2 x 125 MVA
South Okkalapa 230/66 kV Trans. - 2 x 125 MVA
Kyaikkasan 230/66 kV Trans. - 2 x 125 MVA
Thida 230/6 6kV Trans. - 2 x 125 MVA
66 kV Gen. 50 MW
Tilawa
230/66 kV Trans. - 2 x 100 MVA

Table 3 Capacities of Facilities at 230/33 kV Substations

Estimated
33 kV Power Existing
230/33 kV Substation Capacities After
Supply Facilities Capacities
Expansion
66/33 kV Trans. 60 MVA
Ahlone
33 kV Gen. 100 MVA
Hlaingtharyar 230/33 kV Trans. 2 x 100 MVA
230/33 kV Trans. 3 x 100MVA
Hlawga
33 kV Gen. 210 MVA
Thanlyin 230/33 kV Trans. 100 MVA 2 x 100 MVA
Wartayar 230/33 kV Trans. 100 MVA
230/33 kV Trans. 100 MVA
Thakheta
33 kV Gen. 50 MVA
Iwama 33 kV Gen. 36 MVA
West University 230/33 kV Trans. 2 x 100 MVA

The Second Site Investigation -8

 The estimated loads of 230 kV substations were listed as follows.

Table 3 Maximum Power Demand Forecast for 230 kV Substations in 2020

66 kV Load (MW) 33 kV Load (MW)

Ahlone 391 Ahlone 84

Bayintnaung 189 Hlaingtharyar 99

Hlawga 45 Hlawga 263

Thakheta 298 Thanlyin 99

Iwama 231 Wartayar 49

East Dagong 189 Thakheta1 38

South Okkalapa 189 Thakheta2 38

Kyaikkasan 189 Iwama 20

Thida 189 West University 99

Tilawa 168 合計 788

合計 2,081

The power generators in around Yangon area were set out as shown in the following table.
The numerical values of power outputs from Thaketa, Ahlone, Ywama and Hlawga were
used that were also used in the previous study.

Table 4 Power Outputs of Generators in around Yangon Area in Base Case

Power Stations In service Out of service
Tilawa 50 MW 0 MW
Thakheta 92.2 MW 0MW
Ahlone 278.4 MW 0MW
Ywama 223.5 MW 0MW
Hlawga 104.7 MW 51.1 MW
TWH Thailand 500 MW 0MW
Ngayotekaung 540 MW 0MW
Dawei 450 MW 0MW

This case can be considered as the case with large power outputs of generators in around
Yangon area.

(3) The Results of Power Flow Analysis for the 500 kV and 230 kV System in around
Yangon around 2020 (Base Case)
Figure 4 shows the results of power flow calculation of the 500 kV and 230 kV system in
The Second Site Investigation -9
around Yangon around 2020 (base case) with modeling the original plan by MEPE.
The power flow at the intervals of Hlaingtayar – Ahlon and Kyaiklat-Ahlone exceed the
capacity of their transmission lines. Some intervals of the 230 kV transmission lines become
overloaded around Hlawga, East Dagon and Ahlone when the single circuit is dropped.
The overload of an intervals caused by dropping a single circuit would make circuit
breakers opened through working of protection relays and it is feared that other intervals are
also dropped out in a cascading manner causing a large black out.
For example, the power flow of Ahlone – Thida becomes 477 MW when its single circuit is
dropped causing overloading at this interval and making its circuit breakers opened. This
causes the other overloaded transmission lines. Figure 5 shows the power flow in this
situation.
Some intervals of the transmission lines such as Myaungtagar – Hlawga – Thaketa、
Phayargyi – East Dagon – Thaketa become overloaded. At that time, protection relays work
and make their circuit breakers opened causing multiple circuits dropped. In this case, large
power shortage can be expected. The similar situations is considered for the overloaded
intervals.

The Second Site Investigation -10

 Power Plant THARYARGONE

Substation with transformers to its lower side TAUNGOO

Switch yard 540 450

Being planned
500 kV transmission line
230 kV transmission line PhaseII Project PHAYARGYI
655
DAWEI

387

23 144 (180)
When
MYAUNTAGAR 329 Myuntagar-Hlawga
dropped
120 KAMARNAT
89
Overloaded power flow
*** under normal operation 419
(285)
(***) Overloaded power flow in
case of fault of a single When N-1
250 (314)
circuit
When Tharayargonr-Hlawga
dropped
138
HLAWGA
49
HLAINGTAYAR 500kV 163
540 184
830

NGAYOTEKAUNG 28 E. DAGONG

216
HLAINGTAYAR 6 223
387 YWAMA
S. OAKKALALAR
100 189 THAKETA
BAYINTNAUNG 190

406 KYAIKASAN
AHLONE 57
313
THIDA
THANLYIN
504
(477)
195 When N-1 118
KYAIKLATT
DALA

305 TILAWA

Blue colored figures indicates over loaded power flow (MW)

Figure 4 Power Flow for Base Case in 2020

The Second Site Investigation -11

 Power Plant THARYARGONE
TAUNGOO
Substation with transformers to its lower side
Switch yard
Being planned
500 kV transmission line PHAYARGYI
230 kV transmission line PhaseII Project
DAWEI

172

MYAUNTAGAR

41
KAMARNAT

*** Overloaded power

593
flow under normal
operation
482

HLAWGA

HLAINGTAYAR 500kV 257

437

NGAYOTEKAUNG E. DAGONG

HLAINGTAYAR 245 387

YWAMA
S. OAKKALALAR

BAYINTNAUNG THAKETA
190
KYAIKASAN
AHLONE

THIDA
THANLYIN

KYAIKLATT
DALA
TILAWA

Blue colored figures indicates over loaded power flow (MW)

Figure 5 Power Flow in Case of a Fault between Ahlone and Thida for Base Case in 2020

The Second Site Investigation -12

(4) Option of 230 kV Interconnection between East and West in Yangon around 2020
An option of the installation of the 230 kV transmission lines connecting the east and west
in Yangon (they may be installed with underground cables due to their locations in a city
area) is studied as a countermeasure against overloaded situations in Base Case.
This option assumes the installation of a single circuit between 230 kV Hlaingtayar and
Bayintnaung and double circuits between Ywama and South Okkalar
The result of the calculation is shown in the following figure. Blue colored lines indicate
newly installed transmission lines. There are no overloaded 230 kV transmission lines in
normal operation. However, some intervals become still overloaded such as
Hlaingtayar-Iwama and 230 kV Hlaingtayara-Bayintnaung after dropping a circuit of their
lines. The overloaded situation still remains when a single circuit is dropped.

The Second Site Investigation -13

 Power Plant THARYARGONE
Substation with transformers to its lower side
TAUNGOO
Switch yard
Being planned 450
500 kV transmission line 555
230 kV transmission line PhaseII Project
PHAYARGYI 544
DAWEI

357

45 122

MYAUNTAGAR
110 456
102 KAMARNAT

339
(224)
99

7
HLAWGA
49
HLAINGTAYAR 500kV 120
540 5
993
378
NGAYOTEKAUNG E. DAGONG
(304) 350
187
(315)
HLAINGTAYAR 175 145
336 YWAMA
254 S. OAKKALALAR
87
444
64 THAKETA
(358) BAYINTNAUNG

123 KYAIKASAN
AHLONE
98
3
THIDA
THANLYIN
187

234 118
KYAIKLATT
DALA

266 TILAWA

Figure 6 Power Flow in the 230 kV System with East-West Interconnection

The Second Site Investigation -14

(5) Option of the Future System Configuration of Fulfilling N-1 Criteria
An option of the installation of both the 230 kV Interconnection between east and west in
Yangon and the eastern 500 kV substation around Yangon as an countermeasure against
overloaded conditions caused by dropping a single circuit of transmission lines as show in
the following figure.
This option does not cause overloaded situations even when a 230 kV single circuit is
dropped except for the lines from Kyaikalat power station. The loads of 500 kV
transformers can be within 120 % of their capacity even when one of their banks is dropped
in this option.
Thus, it is recommended that the installation of a new 500 kV substation in the east of
Yangon or an equivalent power source to supply the power both from the east and the west
of Yangon in addition to the 230 kV interconnection in future.

The Second Site Investigation -15

 Power Plant THARYARGONE
Substation with transformers to its lower side TAUNGOO

Switch yard 618

Being planned 450

500 kV transmission line
230 kV transmission line PhaseII Project
218
PHAYARGYI DAWEI

208 347

MYAUNTAGAR 112

6 104 KAMARNAT
85
Power flows in ( ) indicate
the case of a single circuit 109
fault or a single bank fault

74
639
HLAWGA
3 49

HLAINGTAYAR 500kV
746 E. DAGONG
540
(533) 637
46
NGAYOTEKAUNG (458)
242
145
175 300(212)
HLAINGTAYAR 148
263 YWAMA
93 S. OAKKALALAR
357 (285)
KYAIKASAN THAKETA
BAYINTNAUNG 153
167
92 22
AHLONE 110
37
THIDA
THANLYIN
153

238 262 118

KYAIKLATT
DALA
TILAWA

( ): power flow in case of dropping a single circuit fault or a transformer

Figure 7 Power Flow in the Future System Fulfilling N-1 Criteria (East-West
Interconnection and East 500 kV substation)

The Second Site Investigation -16

(6) Cases without Phase 2 Project
The power flow was calculated in case of not implementing Phase 2 Project for Base Case.
Ngayotekaung and Dawei thermal power stations were assumed to be still connected to 500
kV transmission lines because they were independent from Phase 2 Project.
From the result of the power flow analysis, the power flows at Tharyargone - Hlawga and
East Dagone-Thaketa exceeded the capacities of their lines apart from Hlaingtayar - Ahlon
and Kyaiklat-Ahlon if Phase 2 was not implemented.

The Second Site Investigation -17

 Power Plant THARYARGONE
Substation with transformers to its lower side 249
Switch yard 330
450
Being planned
500 kV transmission line PHAYARGYI
230 kV transmission line PhaseII Project
DAWEI

467

46 178

MYAUNTAGAR
135
205 KAMARNAT

*** Overloaded power flow

under normal operation
500

248

16
HLAWGA
49
HLAINGTAYAR 500kV 196
540 213

NGAYOTEKAUNG 28 E. DAGONG

153
HLAINGTAYAR 24 300
275 YWAMA
S. OAKKALALAR
67 THAKETA
BAYINTNAUNG 190

282 KYAIKASAN
AHLONE 24
175
THIDA
THANLYIN

365
212 118
KYAIKLATT
DALA

288 TILAWA

Blue colored figures indicates over loaded power flow (MW)

Figure 8 Power Flow in Case of Not Implementing Phase 2 Project for Base Case 2020

The Second Site Investigation -18

(7) Effects on Loss Reduction of Transmission Lines by Phase 2 Project
The implementation of Phase 2 Project can reduce the loss of transmission lines. The loss of
the 500 kV and 230 kV system in Myanmar in 2020 was calculated as shown in the
following table.

Table 6 Difference of Transmission System Loss between Before and After Phase 2
Case Myanmar 500 kV and 230 kV Transmission
System Loss
Before Implementation 204.4 MW
After Implementation 179.9 MW
Difference (Effect on Loss Reduction) 24.5 MW
Annual Loss Reduction 64,386 MWh
Conversion for reduction of CO2 emission 45,933 tCO2/Year

Annual loss reduction of the system and its conversion for CO2 emission are estimated as
64,386 MWh and 45,933 tCO2/year respectively by using the loss reduction of transmission
lines at the maximum power demand assuming its annual loss factor 0.3.

- 0.7134 tCO2/MWh* is used as CO2 emission factor

*) Averaged Grid Emission Factor of China/Myanmar listed in “List of Grid Emission Factor” posted on

the Web site of Institute for Global Environmental Strategies in Japan

http://pub.iges.or.jp/modules/envirolib/view.php?docid=2136

- Loss factor is often estimated by the following formula. Assuming Load Factor of 0.48 gives a Loss
Factor of 0.3.

Loss Factor = k x Loss Factor +(1-k) x Loss Factor2 (where k is often used as 0.3 for transmission system

and 0.2 for distribution system)

The Second Site Investigation -19

(8) Power Flow in Case of Lower Power Outputs from Thermal Power Stations in 2020
(Power output from Ngayotekaug in the west is zero)

The power flow would be increased from the northern area where a lot of hydropower
stations will be located to Yangon in case of the lower power outputs from the thermal
power stations in Yangon. The power flow was calculated for the both cases with and
without Phase 2 setting out no power outputs from Ngayotekaug power station located in
the west of Yangon. The power outputs were set out as follows.

Table 7 Power Outputs of Generators in around Yagon in Case of Lower Power Outputs
from Thermal Power Stations in 2020 (Power output from Ngayotekaug in the
west is zero)
Power Stations In service Out of service
Tilawa 50 MW 0 MW
Thakheta 92.2 MW 0 MW
Ahlone 278.4 MW 0 MW
Ywama 223.5 MW 0 MW
Hlawga 104.7 MW 51.1 MW
TWH Thailand 500 MW 0 MW
Ngayotekaung 0 MW 540 MW
Dawei 450 MW 0 MW

Figure 9 shows the power flow with Phase 2 in this generation pattern.
In the similar manner to the base case, the power flows between Hlaingtayar - Ahlon and
Kyaiklat – Ahlon exceed their capacity of transmission lines. There are some intervals of
230 kV transmission lines that have the over loading power flow in case of a fault of a
circuit around Hlawga, East Dagon and Ahlone.
Without Phase 2, the power flow calculation was not converged. This means that the power
transmission is not possible at the maximum power demand without Phase 2. Its calculation
was converged when the maximum power demand was decreased.The power flow became
not to exceed the capacities of the transmission lines when the power demand of Yangon
was decreased by around 28%. The Figure 10 shows the results of the power flow
calculation for this case.

The Second Site Investigation -20

 Power Plant
Substation with transformers to its lower side THARYARGONE
TAUNGOO
Switch yard
Being planned 450
500 kV transmission line 956

230 kV transmission line PhaseII Project

PHAYARGYI 628
DAWEI

390

58

MYAUNTAGAR 767
157 (194)
168 When
89 KAMARNAT
Myuntagar-Hlawga
Overloaded power flow dropped
*** under normal operation
429
AYOTEKAUNG
(***) Overloaded power flow in (291)
case of fault of a single When N-1
257 (327)
circuit
When Tharayargonr-Hlawga
dropped
86
HLAWGA
49
HLAINGTAYAR 500kV 168
0 203
765

NGAYOTEKAUNG 28 E. DAGONG

198 14
HLAINGTAYAR 232
355 YWAMA
S. OAKKALALAR
85 189 THAKETA
BAYINTNAUNG 190

376 KYAIKASAN
AHLONE 52
280
THIDA
THANLYIN

470
199 (446) 118
KYAIKLATT When N-1
DALA

301 TILAWA

Figure 9 Case of Lower Power Outputs from Thermal Power Stations in 2020 (Power
output from Ngayotekaug in the west is zero)

The Second Site Investigation -21

 Power Plant
TAUNGOO 223
Substation with transformers to its lower side
Switch yard 450
Being planned PHAYARGYI
500 kV transmission line
230 kV transmission line PhaseII Project 447
DAWEI

423
[Power Demand in Yangon
22 is decreased by 28%] 143

MYAUNTAGAR
140
142 KAMARNAT

395

111

88
HLAWGA
36
HLAINGTAYAR 500kV 145
0 131

NGAYOTEKAUNG 43 E. DAGONG
22 5
HLAINGTAYAR 252
37 YWAMA
73
S. OAKKALALAR
75 198 137 THAKETA
BAYINTNAUNG

19 KYAIKASAN
AHLONE
1
68
THIDA
THANLYIN
204

247 71
KYAIKLATT
DALA

253 TILAWA

Figure 10 Case of Lower Power Outputs from Thermal Power Stations in 2020 (Power
output from Ngayotekaug in the west is zero) without Phase 2 and decreasing power
demand of Yangon by 28%

The Second Site Investigation -22

(9) Option of the Future 500 kV and 230 kV system in Yangon
When the maximum power demand of Yangon will reach 4,000 MW from 2,869 MW that is the
maximum power demand of Yangon in 2020, it is considered that more four substation at least
will be required even in consideration with the expansion of the existing substations. The
installation of the east-west interconnections and the east 500 kV substation are both considered
as the effective countermeasures against overloaded conditions. An option of the future 500 kV
and 230 kV system in Yangon is shown in the following figure.

The Second Site Investigation -23

 THARYARGONE
Power Plant TAUNGOO
Substation
500 kV transmission line
230 kV transmission line

PHAYARGYI DAWEI

MYAUNTAGAR

KAMARNAT

HLAWGA

HLAINGTAYAR 500kV
E. DAGONG
N. OAKKALAR
NGAYOTEKAUNG

HLAINGTAYAR
YWAMA
S. OAKKALALAR
KYAIKASAN
BAYINTNAUNG THAKETA

AHLONE

THIDA
THANLYIN

KYAIKLATT
DALA
TILAWA

Figure 11 Option of the Future 500 kV and 230 kV System in Yangon

The Second Site Investigation -24

(10) Recommendations for Power System Configuration
The followings can be raised as the candidates of recommendations for future power system
configuration.
Implementation of 500 kV and 230 kV transmission lines and substations planned by
MEPE including Phase 2 Project on schedule
Installation of 230 kV transmission lines connecting the east and the west in Yangon
through Ywama-S.Oakkalar and Bayintnaung-Kyaikasan and doubling circuits of
Hlaigntayar-Bayintnaung and Thaketa-Kyaikasan up to around 2020. It will contribute to
secure the power supply to the substations planed by MEPE responding to the rapid
growing of power flow from the west to the east in Yangon.
Installation of the new 500 kV substation in the eastern part of Yangon in around East
Dagon to supply power from the east. In order to prepare this, the transmission line from
Pharyargi to East Dagon is considered to be constructed as 500 kV design lines. is
installed.
More 230 kV substations apart from the current planned ones will be required in Yangon
city.
Abovementioned recommendations would be required even for the situations where power
outputs from generators in around Yangon are relatively large. However, the detailed
studies will be required including the fault current analysis regarding the bulk power
system in Yangon because the system power flow can be changed in accordance with the
power generation plans and their operation.

The Second Site Investigation -25