Restoration Procedure of NER Grid Nov-2013

7/23/2019 Restoration Procedure of NER Grid Nov-2013

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BLACK START

AND

RESTORATION PROCEDURES

OF

NER GRID

- 9

:2013

( )

,

7930069th Revision

Month: November2013

POWER SYSTEM OPERATION CORPORATION LTD(A wholly owned subsidiary of POWERGRID)

NORTH EASTERN REGIONAL LOAD DESPATCH CENTRE,Shillong793006


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Black start and Restoration Procedures of NER Grid

INDEX

CHAPTER DESCRIPTION PAGE NO

1 Black Start Facility 1-3

2 System Restoration Approach 4-9

3 Power Maps of NER 10-18

4 Network Diagram of NER 19-27

5 Broad classification of North Eastern Regional Grid 28-34

6 Black Start & Restoration Procedures 35-76

6.1 Restoration of NER Grid after total collapse, when

power from Eastern Region (ER) is available

36-55

6.2 Restoration of NER Grid after total collapse, when

power from Eastern Region (ER) is not available

56-71

6.3 Restoration of 400 / 132 kV Network comprising of

Manipur, South Assam, Mizoram, Tripura, AGTPP and

Palatana after partial collapse.

72-75

6.4 Restoration of 132 kV Network comprising of Manipur

(except Jiribam) and Loktak, after partial collapse.

76-76

7 Reporting Procedure 77-81

List of Annexures

Annexures DESCRIPTION PAGE NO

i) List of Power Stations with black start facilities 83

ii) List of Major sub-stations with synchromising facilities 84

iii) List of shunt reactors in NER 85

iv) Addition of New Transmmission Lines 86

v ) Three phase fault level of Major Sub-stations in NER 87


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North Eastern Regional Load dispatch Centre, Shillong

Black Start Facil i ty1.1 ----- Existing Black Start Facilities

1.2 ----- Survival/ Auxiliary Power requirement

1.3 ----- Startup power requirement

1.4 ----- Synchronizing facilities at Power Stations / major Sub-Stations

1.5 ----- Shunt Reactors at major Power Station and Sub-Stations

CHAPTER 1


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1.1 Existing Black Start Facilities:

A list of Generating Stations of NER (North Eastern Region) having black start facilities

is elaborated in Annexure-I

1.2 Survival/ Auxiliary Power requirement:

Survival/Auxiliary power is required to avoid damages of some equipment as well as

functioning of some essential facilities, in case of supply failure. Immediate

arrangement of power is very essential for the following:-

1. Battery Charging

2. Emergency Lighting

3. Compressors for breaker operation4. Lubricating Oil Pumps

5. Communication & Telemetry System

6. Turbine Emergency Oil Pump

In power stations of NER, auxiliary power requirement is very nominal i.e. around 100-

150 kW as unit sizes are small except Ranganadi units.

1.3 Startup power requirement:For restoration of Generating Unit, startup power is required for its auxiliaries. The

requirement of Startup power of various units is as follow:-

Gas - 2 % of Unit Capacity

Hydro - 1 % of Unit Capacity

Startup power requirement for Gas Generating Unit is high as the major auxiliaries like

Gas Compressor, BFP, ID Fan, FD Fan, CW Pump etc. are of bigger size and the

starting torque is large. However, startup power requirement for Hydro Generating Unitis less because of few auxiliaries.

List of DG Set installed in the Generating Stations is atAnnexure-I

1.4 Synchronizing facilities at Power Stations / major Sub-Stations:

Synchronizing facilities play a vital role in building up of systems and also for inter-

connection of different sub-systems/islands. List of major Sub-Stations which have

synchronization facilities is indicated at Annexure-II.


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1.5 Shunt Reactors at major Power Station and Sub-Stations:

It is very essential to contain voltage during the restoration process of a collapsed

system. During the early restoration process, lines are generally lightly loaded due to

the restricted drawl by the drawing utilities and voltage starts rising up in different busesas system size grows. Shunt Reactors play a vital role to contain voltage. List of Shunt

Reactors available in NER is indicated in Annexure - III.


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SYSTEM RESTORATION APPROACH2.1 ----- General Guidelines

2.2 ----- Initial Course of Action

2.3 ----- Important Considerations during Restoration

2.4 ----- Special Consideration in extending/availing start up power

2.5 ----- DONTS

CHAPTER 2


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The following specific points must be adopted considering the importance of system

restoration:-

2.1 General Guidelines:i) This document should be available in the Control Room of each Load Despatch

Centre & readily accessible to all system operators.

ii) Black Start and Restoration Procedure of Regional Grid under various conditions

(Partial / Total Blackout) shall be reviewed /updated by NERLDC annually in

consultation with NLDC, all Users, STU, SLDC, CTU and NERPC Secretariat.

(As per Clause No 5.8(a) of IEGC)

iii) Black Start and Restoration Procedure of each system of Users/STU/CTU withina Region under various conditions (Partial / Total Blackout) will be finalized by

the concerned Users/STU/CTU in co-ordination with NERLDC. The procedure

will be reviewed, confirmed and/or revised once every year. Mock trial run of this

procedure for different sub-system shall be carried out by Users/STU/CTU at

least once in every six months under intimation of NERLDC. Diesel Generators

set for black start would be tested on weekly basis and test report shall be sent to

NERLDC on quarterly basis. (As per Clause No 5.8(b) of IEGC)

iv) List of essential loads with categories to be prepared by User/SLDC and sent to

NERLDC. Inter State/Inter Regional links, synchronizing points and essential

loads to be restored on priority shall be available with NLDC, RLDC & SLDC. (As

per Clause No 5.8(c) of IEGC)

v) NERLDC will co-ordinate entire restoration process through SLDC /ISGS

/POWERGRID etc.

vi) During restoration process, NERLDC is to be allowed to operate the Grid with

reduced security standard for voltage and frequency in order to achieve fastest

possible recovery. (As per Clause No 5.8(d) of IEGC)

vii) All communication channels required for voice communication during the

restoration process must be operational. At least one channel of voice

communication is to be kept free for NERLDC communication. (As per Clause No

5.8(e) of IEGC & As per Clause No 17 of CEA (Grid Standards) Regulation)

viii) Healthiness of communication system and ancillaries at all Load Despatch

Centres, Power Stations and Sub-Stations should be checked at least once in


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every week to ensure availability of communication system during the periods of

crisis.

ix) List of phone numbers(V-SAT, Landline, Mobile & ULDC) of Control Rooms of

all Load Despatch Centres, Power Stations and important Grid Sub-Stationsshould be available at all Control Rooms and to be distributed to all concerned.

Any change or addition of above phone numbers should be incorporated time to

time and to be communicated to all concerned.

x) Constituents should organize one day appreciation course on power system

restoration at regional level, at least once in a year for

a. Top Management Group/Chief of Load Despatch Centres

b. Load Despatch Personnel/Power System Operators/Sub-Station

Operators

xi) System Operators are expected to be thoroughly conversant with

a. Reactive Capability of Generators

b. Voltage Control through the following means :-

Charging the shorter line first

Switching off Capacitor Bank

Taking Bus Reactors into service

Charging Transformers and taking Bus Reactors into service

Converting Line Reactors into Bus Reactors wherever feasible.

Operating Generators at minimum Voltage levels

Changing Transformer Taps

Energisation of fewer High Voltage Lines.

c. Network connectivity by heart and

d. They should be able to converse fluently in Hindi/English

xii) Power Station which has Black Start capability should be tested at least once in a

month. Power Station which has DG Set should be explored for Black Start

Capability.

xiii) Synchronization facility wherever available should be checked periodically and

should be kept in working condition. Periodic report of non-functioning of

Synchronoscope is to be sent to NERLDC.

xiv) All equipment such as Disturbance Recorders and Event Loggers shall be kept in

healthy condition, so that under no condition such important data is lost. Periodic

report of non-functioning of Disturbance Recorder/Sequential Event Recorder to

be sent to NERLDC. (As per 15.4 of CEA Grid Standards Regulation)


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xv) Priority wise loads are to be secured in steps during restoration process. This is

to be documented by each User/SLDC and informed to NERLDC.

xvi) OLTC of Transformers shall be tested at least once in a week. Periodic report of

non-functioning of OLTC of Transformer to be sent to NERLDC.2.2 Initial Course of Action:

i) Assess (a) extent of black out, (b) whether any sub-system/island is alive or not,

(c) whether interconnection with Eastern Region is still there or not. If

interconnection with Eastern Region is there, then how much load can be

connected

ii) Appraise the severity of disturbance to all concerned.

iii) Open all circuit breakers at Power Station / Sub-Stations that have blacked out,to establish well defined starting point of restoration.

iv) Note the relay indications and reset them, if operated.

v) Check whether any equipment or any element has suffered damage or

developed a technical snag.

vi) Chalk out the optimum path for restoration after checking the grid elements that

were under outage before disturbance.

vii) Defer all planned outage as per IEGC 5.7.4 (g)

2.3 Important Considerations during Restoration:

i) Generating Stations which have black start facilities have to start up immediately.

ii) Availability of Generation Capacity in each island / sub system to be ensured.

iii) Availability of transmission lines in the interconnection between islands / sub

systems to be ensured.

iv) Load to be added in small steps with smaller and radial loads. Larger load may

be connected after consultation with NERLDC.

v) For developing island / sub system, special care should be taken to closely co-

ordinate the load pick-ups with the ramp rate of generation and to be ensured

that the frequency of the island is maintained within sustainable limit (around 50

Hz).

vi) If required, Governor and AVR of the units of the island are to be kept in manual

mode.

vii) UFRs are to be kept deactivated as frequency excursions at this stage may be

wider than normal condition. SPS are also to be kept deactivated.


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viii) A reasonable active to reactive power ratio is to be maintained so that the

machine can be operated normally.

ix) Auxiliary power to be readily available so that machine can be operated normally.

x) Total auxiliary power drawn by the sub-system to be kept within 3% of thecapacity of the source.

xi) Before synchronization between two islands there should be proper co-ordination

for frequency adjustment.

xii) Risky synchronization shall be avoided as small island may not be able to survive

the jerk

xiii) While releasing loads, it is to be ascertained whether machines can supply the

power.

xiv) Tap Position of Transformer, Bus Voltage and Frequency at Power Stations and

Sub-Stations should be closely monitored to ensure that over fluxing does not

occur.

xv) Shift personnel should promptly formulate the strategy to be adopted in co-

ordination with NERLDC for quick restoration of the Grid.

xvi) The work of restoration in the Control Room should be shared & coordinated

among the shift personnel for smooth & quick restoration. Crisis Management

Group to be formed, consisting of expert personnel & called for early restoration

of the system.

xvii) Shift personnel should preferably be retained till restoration is over, before

handing over the charge to the next shift.

2.4 Special Consideration in extending/availing start up power:

I. Power Plant Operators should be able to differentiate between the followings :

a. Full auxiliary power needed to start all machines

b. Minimum auxiliary power needed to start a minimum number of

machines.

II. For availing start up power, the following considerations should be kept in mind :

a. Nearness to the source

b. 132 kV lines vis--vis 220 kV/ 400 kV lines

c. Shorter route having a number of intermediate sub-stations vis-a-vis

longer route having very few/ no intermediate sub-stations


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III. For extending start up power from one sub-system to another sub-system or from

one utility to another utility, the following clear-cut authority should be given to

SLDC :-

a. Line through which start up power is to be extendedb. Quantum of such start up power

c. Normal time period admissible

IV. Concerned SLDC should also be empowered to resort to load shedding or

bring up additional generation wherever possible, to extend start up power

to neighboring sub-systems/utilities during the period of crisis.

2.5 DONTS:

i) Do not panic

ii) Do not load any Generator beyond 80% of its capacity

iii) Do not load any Line/ICT beyond 80% of its capacity

iv) Do not hastily connect loads and ensure that the island / sub-system frequency

be within sustainable range

v) Once power extended to a Power Station/Utility, it should not be withdrawn

except in case of extreme emergency and without intimation to NERLDC, as

actions taken up at Power Stations would have to be redone.

vi) No communication disputes should be raised during the restoration period.

vii) Till the restoration procedure is over, load despatch centers should not be

disturbed in undesirable manner while discharging their duties and they should

not be expected to function as Management Information System.


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Power Maps of NER3.1 ----- NER Network

3.2 ----- Assam Network

3.3 ----- Arunachal Pradesh Network

3.4 ----- Meghalaya Network

3.5 ----- Manipur Networh

3.6 ----- Mizoram Network

3.7 ----- Nagaland Network

3.8 ----- Tripura Network

CHAPTER 3


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9

WestBengal

3.1 POWER MAP OF NORTH EAST REGIONAL GRID

Chin

Along

Daporizo

BhutanRanganadi

Ziro

Naharlugan13

Dhemaji

Tinsukia

Dibrugarh

Doomdooma

Margherita

KhupiBhalukpong

NirjuliMajuli

Maran

Sibsagar

AGBPP

17

Bhutan

Birpara(ER)

Gelyphu(Bhutan)

Salakati

Motonga(Bhutan)

Rangia

Balipara

921

Gohpur

12 14

15 Mariani(PG)

Nazira

18

16

Mokokchung

Deomali

Binaguri(ER)

Gossaigaon

Gauripur

Bongaigaon

BTPS 2

1

BTPS (NTPC)

4

3

Kukurmara

5 7

Kahilipara6

8

Sarusajai 9

11

10Misa

SamaguriGolaghat

Bokajan

Doyang

WokhaKiphire

Rongkhon

Agia

Boko8

54

6 7

Langpi

Kopili Sankardevnagar

Diphu

Dimapur

Dimapur (S) Kohima

Meluri

NEEPCO (in MW)

Nangalbibra3

Mawngap

Nongstoin Mawlai

NEIGRIHMS

2 1Khleihriat(S) Khandong

Haflong Karong

Ranganadi - 3x135

Doyang - 3x25

Cherapunjee NEHU LeshkaKhleihriat

Haflong

AGBPP - 4x33.6+2x35+3xAGTPP - 4x21

BangladeshLumshnong

Dullavcherra

Badarpur

19 20

SrikonaPailapool

Jiribam

Imphal(S)

Imphal

Rengpang

Yaingangpokpi

Khandong - 2x25

Kopili - 4x50

Kopili St II - 2x25

Tripura

1. Dharmanagar

2. Kailashahar

3. Kamalpur

4. Dhalabil

Meghalaya

1. Umiam

2. Umiam St I3. Umiam St II

4. Umiam St III

Bangladesh 13

4 2AGTPP

Kolasib

Silchar

BairabiLoktak

Churachandpur

Kongba

Ningthonkhong

Kakching

Important Lines (in ckm)1. 400 kV Misa-Balipara D/C - 190

2. 400 kV Balipara-Bongaigaon D/C - 5803. 400 kV Balipara - Ranganadi D/C - 3324. 400 kV Bongaigaon - Binaguri D/C - 436

NHPC (in MW)

Loktak - 3x35

LEGEND

400 kV -5. Agartala6. Bodhjangnagar

5. Umiam St IV6. Umtru

8 95 6

710

KumarghatLuangmual 1. 220 kV Misa - Dimapur D/C - 247

220 kV -132 kV -

7. Jirania8. Baramura

9. Teliamura

10. Ambasa

11 Surjamaninagar

Assam

7. EPIP II (Norbong)

8. EPIP I (Raja)

9. Killing (Byrnihat)

11

Rokhia

Udaipur

Palatana

P.K. BariAizawl

Zuangtui

Serchhip

(Bukpui)

Saitual

2. 220 kV Misa - Mariani S/C - 220

3. 220 kV Misa- AGBPP S/C - 382.9

4. 220 kV Misa - Samaguri D/C - 68.8

5. 220 kV MIsa - Kopili T/C - 221.4

6. 220 kV Samaguri - Mariani S/C - 168

7. 220 kV Mariani - AGBPP S/C - 162.98. 220 kV Balipara - Samaguri S/C - 65

Hydro -

Thermal -

POWERGRID

NEEPCO

NHPC

1. Jogigopa2. Dhaligaon

3. Nalbari

4. Bornagar

5. Sipajhar

6. Sisugram

7. CTPS

8. Narengi9. Rowta

10. Baghjap

11. Depota

12. Pavoi

13.

NLakhimpur

14.- Bokaghat15. Jorhat

16.LTPS

17.NTPS

18. Mariani

19. Panchgram

20.

Panchgram(New)

BangladeshKhawiva

(Lunglei)

9 - 220 kV Sarusajai - Samaguri D/C - 247

10. 220 kV Bongaigaon - Salakati S/C - 1

11. 220 kV Salakati - BTPS D/C - 8

12. 220 kV Sarusajai - Langpi D/C - 216.4

AssamMeghalaya

Tripura

Others

11


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)

g

.2 POWER MAP OF ASSAM

Doomdooma

inaguri (PG)Gelyphu(Bhutan) Motonga

Khupi (NO)

North Lakhimpur

Ranganadi (NO)

Nirjuli (PG)

Gohpur

Dhemaji Tinsukia

Dibrugarh

Maran

Margherita

AGBPP (

NTPS

Birpara (PG)

Salakati (PG)

Bhutan (Bhutan) Balipara (PG)Ghoramari

Rowta

DepotaPavoi

MajuliLTPS

SibsagarNazira

Deomali (AP)

Gossaigaon

BTPS(NTPC

Bongaigaon (PG)

Dhaligaon

Bornagar Rangia

Nalbari

Sipajhar

Sisugram

CTPS

Bokakhat

SamaguriGolaghat

Jorhat (Garmur)

Mariani

MokokchungBTPS

AgiaGauripur

Jogigopa

Boko

KahiliparaBagjhap

Langpi

Misa (PG)

Sankardev Nagar

Bokajan

MeghalayaKukurmara

Sarusajai Kopili (NO)

Diphu Dimapur(NG)

NarengiKilling

(Byrnihat) (ME) Khandong (NO)Dimapur (PG)

Umtru (ME) Haflong

Khliehriat (PG)

Haflong (PG)

Lumshnong (ME)

Badarpur (PG)

BangladeshDullavcherra

TripuraPalatana (OTPC)

Dharmanagar (TR)

Kumarghat

Panchgram(old)

Panchgram(New

Srikona

Silchar

Kolasib (MI)

Pailapool

Jiribam (PG) Legend400 kV

220 kV

132 kV

66 kV

Gas

Hydro

12


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Bhutan

3.3 POWER MAP OF ARUNACHAL PRADESH

Legend400 kV220 kV132 kV

Hydro

Along

Daporizo

Ziro (PG)

Ranganadi

Bhalukpong

Khupi (NO)

Naharlagun

Nirjuli (PG)

AGBPP (NO)

Deomali

Balipara (PG)Gohpur (AS)

13


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Kahilipara (AS)

Sarusajai (AS)

Khandong(NO)

3.4 POWER MAP OF MEGHALAYA

1.Adhunik Cement

2.Hill Cement

3.JUD Cement4.GVIL Cement

10. Maithan11. Sai prakash12. Greystone13. Mega carbide

Kahilipara(AS)

5.CMCL

6.MCL7.Trishul8.Nalari

14. New Umtru

Agia (As)

Bongaigaon (PG)

AssamSarusajai (AS)

Kukurmara(AS)

EPIP II (Norbong)

8Misa (PG)

9. Shyam Century

Killing(Byrnihat) Umtru

7 13

1211 EPIP I (Raja Bagan)

Mendipathar14 9 10

Ampati Nongstoin

Umiam St IV

Umiam St IIUmiam St I

Umiam St III

Umiam

NEIGRIHMS

NEHU

Legend

400 kV

Rongkhon

(Tura)Nangalbibra

Mawngap

Sohra

(Cherapunjee)

Mawlai

Leshka

Khleihriat

Khleihriat (PG)1

Lumshnon2

34

6 5

220 kV132 kV Bangladesh

Silchar (PG)Panchgram (AS)Badarpur (PG)

14


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AizwalPG

3.5 POWER MAP OF MANIPUR

Dimapur (PG)

Kohima (NG)

Karong

Haflong

Badarpur (PG) Yaingangpokpi

Pailapool (AS)

Imphal

(PG) Yurembam

Jiribam

(PG)

Rengpang Kongba

Loktak (NH) Ningthoukhong

ChurachandpurKakching

Mizoram Legend132 kVHydro


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Tripura

Bangladesh

My

anmar

3.6 POWER MAP OF MIZORAM

Badarpur (PG)

Bairabi

Jiribam (PG)

Kolasib

Kumarghat

Vairengte Serlui-B

Luangmual

Aizwal (PG) Zuangtui

Saitual

Serchhip(Bukpui)

Khawiva

(Lunglei)

Lungse

Legend

132 kV

66 kV


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ArunachalPradesh3.7 POWER MAP OF NAGALAND

Mariani (AS)

Naginimara

TuliMon

Tizit

Mokokchung

Doyang (NO) Tuensang

Bokajan (AS)Dimapur (PG)

WokhaLikhimro

Misa (PG)1

Dimapur

Zunheboto

Kiphire

Chumukedima Meluri

GaneshnagarKohima

Karong (MA)

Imphal (PG)Legend

220 kV

132 kV66 kV

Hydro


20/89

Aizwal(PG)

M

izoram

3.8 POWER MAP OF TRIPURA

Dullavcherra (AS)

Dharmanagar

Badarpur (PG)

Silchar

Kailashahar

KamalpurP K Bari

Kumarghat

JiraniaBodhjangnagar

Dhalabil

(Khowai)

Ambasa

Agartala AGTPP (NO)Teliamura

(Gamaitila

Badarghat Baramura

Rokhia

Surjamaninagar

Gokulnagar

Udaipur

Palatana

(OTPC)

Sonamura

(Rabindranagar)

Amarpur

Gumti

Bagafa

Belonia

Sabroom

Satchand Legend

400 kV

132 kV66 kV

Gas


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Network Diagram of NER4.1 ----- NER Network

4.2 ----- Assam Network

4.3 ----- Arunachal Pradesh Network

4.4 ----- Meghalaya Network

4.5 ----- Manipur Networh

4.6 ----- Mizoram Network

4.7 ----- Nagaland Network

4.8 ----- Tripura Network

CHAPTER 4


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37

63

3

25

92

69

13

118

15

4

18

12

37

28

41

4

9

12

41

46

35

7

18

10 3

126

217

160km

50

2 .23

28 8

30

24

7

1

57

106

72 6

0 45

10

7

73

12

11

34

65

76

2x315

95

15

4x25

45

67

101

124

63

50

1

50

65

26

89

35

39

20

169

1

26

36

53

13

2

80

22

42

60

50

58

40

50

53

42

4.1Network D iagram of Nor th Eastern Regional Gri dRanganadi(NO)

Bongaigaon(PG) 50

2x80+2x50 50 290298 30 % 63

Balipara (PG)

50 16650 2x360

3x135

Ziro(PG Daporizo

New Siliguri(ER) 224 63Motonga (Bhutan)

Rangia(AS)Bhalukpong(AR) 63

42 Nirjuli(PG) 4 1820 (AR) A

(

New Siliguri(ER)218

63 63

315 106

Nalbari (AS)

22

Sipajhar(AS)49

38 44

Khupi(NO) 22

72

45

282x50

31550+80 N. Lakhimpur

(AS) Naharlagun(AR)

45

AGBPP(NO

87 82

Pasigh

Birpara(ER)

160 Dhaligaon42 Bornagar(AS 34

27

108 64Rowta(AS) Depota(AS)

9

Tezpur(AS)

4x25 Dhemaji(AS)

1x10019 )

4x33.6+2x35

(AR)

Roing

Salakati(PG Gaupur 63(AS)

AMP(AS)37

Sisugram(AS) CTPS(AS)

Gohpur(AS) Majuli

222220

Deomali(AR161 (PG)

Gelephu(Bh) 2x50 Gossaigaon(AS) 64 1 BRPL Narengi(AS)20 2x30 Pavoi (AS)

168 163 24 Tez

49 3

22 Kukurmara(A

KaheliparaAS)12

3 2935 5

Dispur(AS) Jagirod (AS)

HPC,J

Sankardev

Nagar

51 77

2x12.5

168

2x12.

Mariani

2x100

20Mariani

New

(PG) Tinsukia

(PG

Nam(PG

BTPS(NTPC)

3x250 MW

Azara (AS) 1x315 803

Boko (AS)

63

3x100

Sarusajai(AS)108

Langpi(AS)

2x50130

Diphu

(AS)

3x50

50Samaguri (AS)

(AS)

Jorhat

(AS)

LTPS(AS)

4x15+3x30+

1x37.2

(AS)

2x50

BTPS .4 Trishul .3 Shyam Century Bokakhat

(AS) 1 .1EPIP II 3Nalari

.4 Maithan

4.4

(AS)45 69

1x50 1x50

2x80+1x1661

2x50Umtru(ME)

4x2.8

30

(ME)

167

EPIP I(ME)

2x160

Sai Prakash.7 Greystone

1Mega Carbide

113

Misa(PG) Golaghat(AS)

Nazira(AS)

2x50

2x25+

NTPS(AS)3x23+1x12.5+

1x30+1x22

Agia

(AS) 70Umiam IV(ME)

8

2x30 10Umiam St III(ME)

2x30 2x31563

Byrnihat(ME) Leshka(ME)3x42

Kopili(NO)Bokajan

(AS)Moran(AS)

Sibsagar(AS)

1x20

43

131 Umiam II(ME) 3 Umiam St I(ME)Umiam(ME) 50 Khliehriat8 26 Kopili StII(NO) 4x50 Ledo(AS)

Palatana

2x9Tura (ME)

Mawngap 33(ME)

4x953

5 7

(ME)

63

5

Khliehriat(PG)

1x251x60+1x160

Khandong(NO)

2x363

80 57

Nangalbibra(ME)

2354

Nongstoin(ME)

Mawlai(ME)

9

NEHU(ME) NEIGRIHMS(ME)

Adhunik Cement

Hill Cement42

JUD Cement

Lumshnong41

2x25

Haflong (PG)63 1

Dibrugarh(AS)

1x125 63

Udaipur(TR)

6 40

Rokhia(TR)6x8+2x21

1x30

Cherapunjee(ME)

Dharmanagar

35 (TR)

Dullavcherra(AS)29

63

(ME)

GVIL Cement

CMCL

77

23 1

219

Badarpur (PG)

Haflong (AS)

Dimapur(PG)

Doyang (NO)

933x25

Mokokc

(PG

247

18 Agartala(TR

)

2x2

45 Dhalabil

50

Kailashor

MCL

63 HPC,P

Panchgram(AS)

19140

2x10027

30Wokha58 (NG)

2x

1

Badarghat3

(TR)

18

AGTPP(NO)8

Kamalpur

(TR) 3231

(TR)(TR

) 2x632x200

1

Srikona(AS)35

Pailapool

(AS)

Dimapur(NG) Kohima

(NG)

Mokokchung(NG)

74

2x100+2x54x21

130

1041

Silchar (PG)

20119

Bairabi(MZ)4x5.7

30

Kolasib(MZ)

Imphal(PG)

20 60Karong(MA)

Kh

36 (

Surajmani Nagar(TR)

Legend

18 Bodhjangnagar(TR)8

2x10

P K Bari(TR)

Kumarghat(PG)

133 Aizawl(PG) 66

172

Jiribam(MA)

Jiribam

Imphal

(MA) Likhimro(NG) 3x8

Ka

400 kV 220 kV

132 kV 66 kV

Line Length in km

7

Jirania(TR)

14 25 45 Melriat

5

Sinhmui(MZ)

20 1

Longmol(MZ)

Rengpang(MA) 40

Saitual(MZ)

(PG)82

42

Yaingangpokpi

(MA)33

23

45

Kongba

(M

Reactor/Capacitor Capacity in MVAR

Transformer Capacity in MVA

30Baramura(TR) Teliamura Ambasa Melriat

(New) (PG)W. Phaileng

Zungtui(MZ)

50

54 69 Loktak(NH) Ningthoukhong Churacha(MA

Installed Capacity in MW 2x5+1x6.5+2x21 (TR) (TR)(Mz) 30 (MZ) Serchip(MZ) Lunglei(MZ) 3x35

11 (MA)

20


23/89

70

1

31

13

63

64

118

259

50

30

126

.2

44

18

1

8

34

113

12

46

73

76

12

11

44

57

5

101

106

43

72

51

60

65

64

39 8

89

20

45

26

50

54

53

22

60

13

39

80

25

36

43

3

53

5 3

NETWORK DIAGRAM OF ASSAM GRID

Bongaigaon(PG) 63

224 63 50

298

290

30% 63Balipara (PG) 73

63 Kameng(NO)

w Siliguri

(ER)

irpara

21863

167

63

63

Killing 2x16

2x25 Rangia

2x16

Khupi 67(NO)

72 2864

2x50

9

315 50

2x10 1x16.5

166

57

50

132x200

Ranganadi(NO)

Pavoi

AGBPP((ER) 160 315 Nalbari Motonga 49 Biswanath Chariali (PG) Itanagar (AR) 4x33.6+2

Salakati2x25

2x50+80

Gauripur

2x16

106

42

22

86

Bornagar

38 Sipajhar

27

Depota2x31.5

Tezpur

Nirjuli(PG)

4x25

77

50+80 N.

45

383

Majuli

63

Dhemaji

2x16

+ 3x319

Deom25

2x50 Gossaigaon .6 BRPL 2x25108 Gohpur 220 163

lyphu 3hutan) 49 3

63

2x16

22

37

DhaligaonAPM

Rowta

2x25 1x16+1x10

Biswanath Charali

168168

2x12.5

2x100 Mariani1x20MV 1x16

20

Mariani New(PG) 3x10

Doomdooma(Rupai)

Tins

2

BTPS BTPS2x80+1x1601x16

2x25 1x12.5+1x16

Sisugram2x25

Narengi 1x16+1x30CTPS2x30

(Pavoi)

452x12.5

MVA

80Mokokchung

NTPC)

x250 Agia 1x315

Kukurmara

632x31.5+1x40 12 20 2x16 3x50

2x25+

1x16

(PG)

LTPS

3x20

1x50

1x40+1x12.5

3

Azara

2x50

Kahilipara

2x10

3 29

Dispur

1x31.5+2x30 2x16

35

2x16

Baghjhap

Samaguri

2x25Sankardev

Jorhat(Garmur

2x16Mokokchung

(NG)69

4x15+3x30+

1x37.2

2x7.5

3x20

2x10

Boko61

1x50

2x40

Sarusajai

3x100

3x31.5

Umtru(ME)

Umtru130

108

Langpi

2x50

34

5050

HPC,J Nagar

(Lanka)

Diphu

2x16

2x5

95

2x16Bokakhat

Golaghat

2x25

1x20+1x10

1x16

3x5

40

Bokajan

2x25

Nazira(Gargaon)

2x25

2x25

Sibsagar

2x16

2x50

1x31.5

2x25+

1x20

1x10

36

2x31

Dibrugarh

NTP

3x23+1x

+1x30+

FCI

50Killing(ME) Misa(PG)

2x315 4x25

124

50

Dimapur(PG)

Dimapur(PG)

Dimapur(NG)

Moran

2x16

74

217

42

Khliehriat 41(PG) 77

Panchgram

63 2x16

Kopili(NO)4x50

Kopili StII (NO)

1x25

119

1x60+1x160

Khandong(NO)

63

107

Badarpur (PG)67

Kolasib(MZ)

Haflong(PG)

12x10

Haflong

63

Silchar (PG)

Lumshnong (ME)

2x63

232

HPC,P

140

2x10

Panchgram

119

Imphal(New)

Kumarghat(PG)

atana (OTPC)247

63 50

160

2x200 191

Srikona Pailapool35

(PG)

15

Legend

400 kV 220 kV

Melriat (PG)

29Dharmanagar (TR)

Dullavcherra

1x3.5

P K Bari

(TR)2x25

3x10 Jiribam(PG)

1x20 132 kV 66 kV

Line Length in km



Installed Capacity in MW21


24/89

n

1

18

Legend

400 kV

220 kV

132 kV

66 k 33 kV

Length in km

tor/Capacitor Capacity in MVAR

nsformer Capacity in MVA

alled Capacity in MW

AGBPP(NO)4x33.66+2x35.01+3x30

Note : 1. For the sake of continuity of the Network, Lines & Buses owned by others shown

2. 400 kV Lines owned by POWERGRID

3 NETWORK DIAGRAM OF ARUNACHAL PRADESH GRID

Khupi(NO)

Bongaigao(PG)

Bhalukpong

30 %

298

290

2x50

63

63

2x315

Balipara(PG)

50+80

Biswanath

Chariali

166

50

2x360

Ranganadi(NO)3x105

45

Ziro(PG)

Daporizo Along

87 82

Pasighat

52

Roing

35

Kimi(NO)

8

1x16Tezpur

(AS)

9

164 4x25 50+8

(PG)

1x20+1x15

Naharlagun

Pare(NO)2x55

1x15 2x5 1x15

20 2x15

Tezu

Kameng (NO)

Samaguri(AS) 63

304

Gohpur(AS)

43 4

4x150 73

Lower Subansiri (NH)8x250

2x20

2x10 Nirjuli(PG)

Itanagar(AP)

Namsai

2x15

Miao

Jairampur

Deomali

19

2x16

Khonsa Changlang

1x100

22


25/89

46

37

9

30

41

9

113

18

.4 .1

.2

.2 82

2 30 3

.7km

.4

1km

.3

26

4.4 NETWORK DIAGRAM OF MEGHALAYA GRID

Misa(PG) Bongaigaon(PG)

Sarusajai(AS)

Kahilipara(AS)

New Umtru2x40 2x160

2

Killing

10

16750

217

63

Silchar(PG)

3

3

Maithan

4

Shyam Ce

Sai Praka

Mendipathar

Agia(AS)

3

Umtru4x2.8

Umiam St IV2x30

1

41

8

10

17

Umiam St II 32x9 12

EPIP II (Norbong)

2x20

Trishul

Umiam St III2x30

Nalari

1x50+2x

Greystone

EPIP I

MegaCarbide

17 69

1x12.5

57 71Mawlai

3x20

Umiam

7

5

2x20

Umiam St I

4x9

532x20

Ampati Rongkhon(Tura)

1x20+4x5

Nangalbibra

2x12.5

Nongstoin 3

Mawngap 2 NEHU

7

NEIGRIHMS

Khliehriat63

8

Legend

1x40

1x12.5

2x20 2x10

Sohra

(Cherapunjee

Hill Cement

AdhunikCement

24

JUD Cement

5

Khliehriat(PG)

Leshka

3x42400 kV

220 kV

132 kV

33 kV

Under const

Lumshnong

2x5 MPL

GVIL CMCLCement

MCL

Under long outage

ine Length in km

eactor/Capacitor Capacity in MVAR

ransformer Capacity in MVA

nstalled Capacity in MW

Panchgram(AS)

23


26/89

101

1

35

22

11

26

60

50

Legend400 kV

132 kV 33 kV

Length in km

ctor/Capacitor Capacity in MVAR

nsformer Capacity in MVA

alled Capacity in MW

Note : 1. For the sake of continuity of the Network, Lines & Buses owned by others shown

5 NETWORK DIAGRAM OF MANIPUR GRID

Kohima(NG)

Karong

Haflong(PG) Imphal

2x20

Yaingangpokpi Kongba Kakching

Badarpur (PG) 67Jiribam

Imphal (PG)42 33 45

Pailapool (AS) 15

(MA)

Jiribam

2x50

20

3x20

23

1x20 2x20

38

Aizwal(PG) 172

1x20

(PG)

40

1x12.5

Rengpang42

Ningthoukhong

2x12.5

1x20

Churachandpur

82

Loktak(NH)

24


27/89

7

107

30

1x12.5+1x6.3Legend

33 kV

66 kV

132 kV 400 k

Line Length in km



Installed Capacity in MW

4.6 NETWORK DIAGRAM OF MIZORAM GRID

Badarpur(PG)

Kumarghat(PG)

Aizawl

(PG)

133

20

66

172

1

1x6.3

1x12.5

Jiribam

(PG)

2x12.5 160

Bairabi

1x12.5

Kolasib(Bawktlang)

Silchar

(PG)

W Phaileng Sinhmui

Luangmual

50

Melriat

Saitual

2x50Melriat

5 54 1x6.3 55

ZuangtuiBukpui Khawiva

2x12.5 2x12.5 (Lunglei)

25


28/89

3

124

169

2

5

1

26

8

50

58

27

36

56

50

4.7 NETWORK DIAGRAM OF NAGALAND GRID

Misa (PG) Bokajan(AS)

Mokokchung (PG)2x50 53

Mariani(POWERGRID)

Dimapur

Doyang (NO)3x25

93 30

1 50

1x25

Mokokchung

Mariani(AS)Tul Nagnimora

(PG)57 34 Tizit Mon

Wokha

1x7.5 46 44 31

Imphal(PG)

Dimapur

3x20

4

Kohima

1x5

74

Meluri

Zunheboto

Kiphire42

Tuensang

1x5

1x7.5 1x5 1x5 1x5

3x8 1x12 3x10

Singrijan Karong(MA)

Legend

33 kV

66 kV

132 kV 220 kV

Line Length in km

Ganesh

Nagar 1x10

Power House2

Chumukidima

1x10

2x10MVA

Nito Farm

Likhimro3x8



12

3 1x5 1x5

Installed Capacity in MWBokajan(AS) Dairy Farm

26


29/89

4.8 NETWORK DIAGRAM OF TRIPURA GRID

22

Silchar 1x4 SonamuraSatchand

2x10 2x15 (Rabindranagar)

5012 Gakulnagar Bagafa

1x4Sabroom

Badarghat 1x15 2x515 1x10

1x15 Belonia

80 251x5+1x10

1x10 Dharmanagar63 24 (Mission Tilla)

233x7.5/2.5/5

Palatana(OTPC)Udaipur 29 Dullavcherra

2x363 1x125 (Banduar) 1x10 (AS)

1x15+2x1 Rokhia 1x30 1x8+2x21 2x2 Kailashar6 40 6x8+2x21 (Gournagar)

3518 2x7.5/2.5/5

1x1

1x15+1x1 3x25+2x20Dhalabil(Khowai) Kumarghat

4518 Agartala

AGTPP(NO) 8(79 Tilla) Badarpur

45 Surajmani Nagar 4x21Kamalpur 119

1x1031 1 Aizawl

1x10 2x100+2x50 104 131

133 20

Gumti 2x1003x5 Bodhjangnagar 126

18 8P K Bari

1x4 1x15 Silchar

Monarchak (NO) Amarpur 2x257 Jirania

1x104 2x10

Legend

400 kV

132 kV

66 kV

33 kV

Line Length in km



Installed Capacity in MW

35

3

247

37

45

25

3

24

31

15

40

30

32

35

4

5

15

18

2x6.3

Baramura 1x3012 25

2x5+1x6.5+2x21 Teliamura

1x15 1x7.5/2.5/5

1x7.5

Ambasa

Teliamura(Gamaitilla) 1x6.3+1x4

27


30/89


Broad classif ication of North Eastern

Regional Grid5.1 ----- 400 / 220 kV Network of POWERGRID

5.2 ----- 220 / 132 kV Network of Assam System

5.3 ----- 220 / 132 kV Network of Arunachal Pradesh System

5.4 ----- 400 / 220 / 132 kV Network comprising of Nagaland, Manipur,

South Assam, Mizoram, Tripura, Meghalaya, POWERGRID andNETC (North East Transmission Company)

CHAPTER 5


31/89


North Eastern Region (NER) comprises of seven states viz Arunachal Pradesh, Assam,

Manipur, Meghalaya, Mizoram, Nagaland & Tripura. NHPC NEEPCO & OTPCL are

the Central Generating Companies presently operating in the region with installed

capacity of 105 MW,1130 MW & 363 MW respectively.Depending on the network connectivity, NER Grid is broadly classified as

follows.

a) 400 / 220 kV Network of POWERGRID

b) 220 / 132 kV Network of Assam System

c) 220 / 132 kV Network of Arunachal Pradesh System

d) 400 / 220 / 132 kV Network comprising of Nagaland, Manipur,

South Assam, Mizoram, Tripura, Meghalaya,POWERGRID andNETC (North East Transmission Company).

5.1 400 / 220 kV Network of POWERGRID:

This is the main back-bone network of NER Grid comprising of 400 kV and 220 kV

transmission lines of POWERGRID (PG). NER Grid is connected to ER Grid through

this network. The network configuration is described as below:

a. 400 kV Bongaigaon (PG) Sub-Station of NER is connected with 400 kV NewSiliguri (PG) Sub-Station of ER through 400 kV D/C New SiliguriBongaigaon

lines.

b. 220 kV Salakati (PG) Sub-Station of NER is connected to 220 kV Birpara (PG)

Sub-Station of ER through 220 kV D/C BirparaSalakati lines. 220 kV Salakati

Sub-Station and 400 kV Bongaigaon Sub-Station are connected through 315

MVA ICT.

c. Bongaigaon (PG) Sub-Station is connected to Balipara (PG) Sub-Stationthrough 400 kV D/C BongaigaonBalipara lines.

d. 400 kV D/C BaliparaMisa lines and 400 kV D/C Balipara Ranganadi lines

connect Balipara (PG) Sub-Station with Misa (PG) Sub-Station and Ranganadi

(NEEPCO) Power Station respectively. 400 kV Bus of Misa is connected to 220

kV Bus through 315 MVA ICT.

e. Misa (PG) Sub-Station is connected with Kopili (NEEPCO) Power Station,

Dimapur (PG) Sub-Station and AGBPP (NEEPCO) through 220 kV T/C Misa


32/89


Kopili lines, 220 kV D/C Misa Dimapur lines and 400 kV S/C Misa

Kathalguri line (charged at 220 kV) respectively.

f. Misa (PG) Sub-Station is also connected to Mariani (Assam) Sub-Station and

Samaguri (Assam) Sub-Station through 220 kV S/C Misa Mariani line and220 kV D/C MisaSamaguri line.

g. Misa (PG) Sub-Station is connected with Killing (Byrnihat) Sub-Station of

Meghalaya through 220 kV D/C MisaKilling lines.

h. Mariani Sub-Station is connected to AGBPP (NEEPCO) through 400 kV S/C

MarianiKathalguri line (charged at 220 kV)

5.2 220 / 132 kV Network of Assam System:

Assam has its own 220 kV & 132 kV Network through which it is connected to the Main

Grid. Except South Assam, connectivity of Assam system with the Main Grid is better

than other states connectivity to the Main Grid. Connectivity of Assam system with the

Grid is as follows:-

a. BTPS (Assam) Sub-Station is connected with Salakati (PG) Sub-Station

through 220 kV D/C BTPS Salakati lines. Again, 220 kV Bus of BTPS is

connected to 132 Bus through 2 X 80MVA + 1 X 160 MVA.

b. Dhaligaon, Barnagar, Nalbari, Rangia, Rowta, Sipajhar , Sisugram and Depota

Sub-Stations are connected with BTPS, Kahilipara, Pavoi, Samaguri and

Balipara (PG) Sub-Stations through 132 kV lines. 220 kV Bus of Samaguri Sub-

Station is connected to 132 kV Bus through 3 X 50 MVA ICT. Again, Samaguri

Sub-station is connected with Balipara (PG) Sub-station through 220 kV

SamaguriBalipara S/C line.

c. Agia Sub-Station is connected with BTPS Sub-Station through 220 kV D/C

BTPS Agia lines. Presently, one circuit of 220 kV BTPS Agia is under

outage.

d. Sarusajai Sub-Station is connected with Agia Sub-Station through AgiaBoko-

Sarusajai line and AgiaSarusajai respectively.

e. Sarusajai Sub-Station is connected with Samaguri Sub-Station,Jahawar

Nagar(GIS) Sub-Station and Langpi Power Station through 220 kV Sarusajai

Jahawar Nagar- Samaguri I and 220 kV Sarusajai Samaguri II lines and

220 kV D/C SarusajaiLangpi lines respectively.


33/89


f. Kahilipara Sub-Station is connected with Sarusajai Sub-Station through four

numbers of 132 kV Sarusajai Kahilipara lines & with Rangia Sub-Station

through 132 kV Kahilipara Sishugram - Rangia & 132 kV S/C Kahilipara

Rangia lines.g. LTPS, NTPS, Tinsukia and Dibrugarh Sub-System is connected with Mariani

Sub-Station and AGBPP through 132 kV S/C LTPS - Mariani and 220 kV D/C

TinsukiaAGBPP lines respectively.

h. Mariani, Golaghat and Bokajan Sub-Stations are connected with Dimapur (PG)

Sub-Station through 132 kV S/C MarianiGolaghat - Bokajan - Dimapur line.

i. Gohpur, Pavoi (Bishwanath Chariali), North Lakhimpur, Dhemaji and Majuli

Sub-Stations are connected with Nirjuli (PG) Sub-Station through 132 kV S/C

Nirjuli Gohpur line. Gohpur, Pavoi (Bishwanath Chariali), North Lakhimpur,

Dhemaji and Majuli Sub-Stations are also connected with Balipara (PG) Sub-

Station through 132 kV Balipara Gohpur line and with Samaguri and Depota

Sub-Stations through 132 kV Samaguri Depota Pavoi line (T-connection

near Depota in between Depota & Pavoi).

5.3 220 / 132 kV Network of Arunachal Pradesh System:

The connectivity of 220 kV & 132 kV Network of Arunachal Pradesh is as follow:-

a) Ziro(PG), Daporizo and Along Sub-Stations are connected with Ranganadi

(NEEPCO) Power Station through 132 kV S/C RanganadiZiro line.

b) Nirjuli (PG) Sub-Station is connected with Ranganadi (NEEPCO) Power Station

& SMS Sub-Station of Arunachal through 132 kV S/C Ranganadi SMS -

Nirjuli line (T Connection at SMS) and also with Gohpur Sub-Station of Assam

through 132 kV S/C NirjuliGohpur line.

c) Itanagar Sub-Station is connected with 132 kV Nirjuli (PG) Sub-Station through

four nos. 33 kV feeders. Again, Itanagar can draw power from SMS Sub-station

via Naharlagun Sub-station through 132 kV SMS Naharlagun-Itanagar line

(Presently charged at 33 kV).

d) Khupi, Kimi Sub-Stations are connected with Balipara (PG) Sub-Station

through 132 kV S/C BaliparaKhupi - Kimi line and Deomali is connected with

AGBPP (NEEPCO) through 220 kV S/C AGBPPDeomali line respectively.


34/89



5.4400 / 220 / 132 kV Network comprising of Nagaland, Manipur, SouthAssam, Mizoram, Tripura, Meghalaya,POWERGRID and NETC (North

East Transmission Company :The connectivity of 132 kV Network comprising of Nagaland, Manipur, South Assam,

Mizoram, Tripura and Meghalaya is as follow:-

1. Nagaland System is connected with the Main Grid through:-

a) 132 kV D/C Dimapur (PG)Dimapur line.

b) 132 kV S/C Dimapur (PG)Kohima line (presently under outage).

c) 132 kV S/C Karong (Manipur)Kohima line.

d) 132 kV S/C Doyang (NEEPCO) - Mokokchung line.

e) 132 kV S/C Mariani (Assam) Mokokchung line (presently under

outage)..

f) 66 kV S/C DimapurBokajan (Assam) line

** Nagaland is also co nnected with As sam sy stem throu gh the fol lowing 33

kV and 11 kV feeders :

i) GargaonNaginimara

ii)SonariTigit

iii)Chanki - Moriani

2. Manipur System is connected with the Main Grid through :-a) 132 kV D/C Imphal (PG)Imphal lines.

b) 132 kV S/C Imphal (PG)Ningthoukhong line.

c) 132 kV S/C Kohima (Nagaland)Karong line.

d) 132 kV S/C Loktak (NHPC)Ningthoukhong line.

e) 132 kV S/C Loktak (NHPC)Rengpang line.

f) 132/33 kV, 1 X 20 MVA Transformer at Jiribam (PG) Sub-Station

3. Mizoram System is connected with the Main Grid through :-a) 132 kV S/C Aizawl (PG)Zuangtui line.

b) 132 kV S/C Aizawl (PG)Laungmual line.

c) 132 kV S/C Badarpur (PG)Kolasib line.

d) 132 kV S/C Aizawl (PG)Kolasib line.

4. Tripura System is connected with the Main Grid through :-

a) 132 kV D/C AGTPP (NEEPCO)Agartala lines

b) 132 kV S/C Kumarghat (PG)P K Bari line


35/89


c) 132 kV S/C Dullavcherra (Assam)Dharmanagar (Missiontila) line

d) 132 kV S/C PalatanaSurjyamani Nagar line

e) 132 kV S/C PalatanaUdaipur line

5. South Assam is connected with the Main Grid through :-a) 132 kV S/C Badarpur(PG)Panchgram line.

b) 132 kV S/C Lumshnong (Meghalaya)Panchgram line

c) 132 kV S/C Dharmanagar (Tripura)Dullavcherra line.

d) 132 kV S/C Jiribam (PG)Pailapool line.

e) 132 kV S/C Haflong (PG)Haflong line.

f) 132 kV S/C Silchar Dullavcherra line.

g) 132 kV S/C SilcharPanchgram line.

h) 132 kV D/C SilcharSrikona lines.

i) 33 kV S/C Khandong (NEEPCO)Umrangshu line.

6. Meghalaya system is connected with the Main Grid through :-

a) 220 kV D/C MisaKilling (Byrnihat) lines.

b) 132 kV D/C Khliehriat(PG)Khliehriat lines.

c) 132 kV S/C Panchgram(Assam)Lumshnong line.

d) 132 kV Agia (Assam)Nangalbibra line.

e) 132 kV D/C Kahilipara(Assam) - Umtru lines.

f) 132 kV D/C Sarusajai (Assam)Umtru lines.

7. The connectivity of the 132 kV System with 400 kV & 220 kV System

& major connectivity of intra 132 kV System:-

a. Dimapur (PG) Sub-Station is connected with Misa (PG) Sub-Station through

220 kV D/C MisaDimapur lines. 220 kV Bus of Dimapur (PG) Sub-Station

is connected to 132 kV Bus through 2X100 MVA ICT.

b. Dimapur (PG) Sub-Station is connected with Imphal (PG) Sub-Station

through 132 kV S/C DimapurImphal line.

c. Imphal (PG) Sub-Station is connected with Loktak (NHPC) Power Station

through 132 kV S/C ImphalLoktak line.

d. Loktak (NHPC) Power Station is connected with Jiribam (PG) Sub-Station

through 132 kV S/C LoktakJiribam line.

e. Jiribam (PG) Sub-Station is connected with Haflong (PG) Sub-Station,

Badarpur (PG) Sub-Station and Aizawl (PG) Sub-Station through 132 kV


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S/C JiribamHaflong line, 132 kV S/C JiribamBadarpur line and 132 kV

S/C JiribamAizawl line respectively.

f. Khandong (NEEPCO) Power Station is connected with Kopili (NEEPCO)

Power Station through 132 kV D/C Kopili Khandong lines. 220 kV Bus ofKopili Power Station is connected to 132 kV Bus through 1X160 MVA ICT.

g. Khandong (NEEPCO) Power Station is connected with Khliehriat (PG) Sub-

Station and Haflong (PG) Sub-Station through 132 kV D/C Khandong

Khliehriat lines and 132 kV S/C KhandongHaflong line respectively.

h. Badarpur (PG) Sub-Station is connected with Khliehriat (PG) Sub-Station ,

Kumarghat (PG) Sub-Station, Jiribam (PG) Sub-Station and Aizawal (PG)

Sub-Station through 132 kV S/C Khliehriat Badarpur line, 132 kV S/C

KumarghatBadarpur line, 132 kV S/C BadarpurJiribam line and 132 kV

S/C BadarpurKolasib - Aizawl lines respectively.

i. Again, Badarpur (PG) Sub-Station is connected with Silchar (PG) Sub-

Station through 132 kV (D/C) BadarpurSilchar lines.

j. 132 kV bus of Silchar Sub-Station is connected with 400 kV bus through

400 / 132 kV, 2 x 200 MVA ICT.

k. Silchar Sub-Station is connected with Palatana Power station through 400

kV D/C SilcharPalatana lines. Palatana Power station is also connected

with Tripura system through 132 kV PalatanaUdaipur & 132 kV Palatana

Surjyamani Nagar lines respectively.

l. Again, Silchar Sub-Station is connected with Killing (Byrnihat) sub-stationthrough 400 kV S/C Silchar Byrnihat line. 400 kV bus of Byrnihat Sub-Station is connected to 220 kV bus through 2 x 315 MVA ICT.

m. Kumarghat (PG) Sub-Station is connected with AGTPP (NEEPCO) and

Aizawl (PG) Sub-Station through 132 kV S/C KumarghatAGTPP line and

132 kV S/C KumargahtAizawl line respectively.


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Black Start & Restoration Procedures6.1 ----- Restoration of NER Grid after total collapse, when power from

ER is available

6.2 ----- Restoration of NER Grid after total collapse, when power from

Eastern Region (ER) is not available

6.3 ----- Restoration of 400 / 132 kV Network comprising of Manipur,

South Assam, Mizoram, Tripura, AGTPP and Palatana afterpartial collapse.

6.4 ----- Restoration of 132 kV Network comprising of Manipur (except

Jiribam) and Loktak, after partial collapse.

CHAPTER 6


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This Chapter explains broad guidelines for restoring the system after black out. The

procedure is split up for the following scenarios:-

1. Restoration of NER Grid after total collapse, when power from Eastern Region

(ER) is available2. Restoration of NER Grid after total collapse, when power from Eastern Region

(ER) is not available

3. Restoration of 400 / 132 kV Network comprising of Manipur, South Assam,

Mizoram, Tripura, AGTPP and Palatana after partial collapse.

4. Restoration of 132 kV Network comprising of Manipur (except Jiribam) and Loktak,

after partial collapse.

NER Grid under above scenarios will be restored after building up of some sub-systems /

islands on the basis of available resources. Source of start up power is to be identified

whether it is available within sub-system / island or outside the sub-system / island for early

restoration. The following procedure is to be adopted for restoration of affected system:-

I. Source of startup power

II. Identifying the critical / essential loads of each sub-system / island

III. Points of synchronization with other sub-system / island

IV. Action to be taken by various Generating Stations and Sub-Stations.

6.1 Restoration of NER Grid after total collapse, when power from ER is

available

For restoration of NER Grid from total collapse condition, a multi-pronged restoration

strategy is envisaged in which some sub-systems and islands are to be built up

simultaneously by utilizing power from Eastern Region (ER) and black start facilities

available in various Power Stations in North Eastern Region.

For restoration of NER Grid from total collapse condition, the following sub-systems /

islands are to be built up in parallel:-

6.1.1 The system, consisting of the following sub-systems are to be built up in

parallel, by utilizing power from ER

SUB SYSTEM#1:a. Main network comprising of Bongaigaon(PG), Salakati(PG),

Gelephu(PG),Balipara(PG),Ranganadi(NEEPCO) ,Nirjuli(PG), Misa(PG),


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AGBPP(NEEPCO), Dimapur(PG), Doyang(NEEPCO), Byrnihat(MeECL),

Kopili(NEEPCO),Khandong(NEEPCO),Khliehriat(PG),Haflong(PG),

Badarpur(PG), Silchar (PG) and Palatana(OTPC).

b. Arunachal Pradeshcomprising of Khupi, Kimi, Ziro, Itanagar andDeomali,c. Central Assam comprising of Gohpur, Depota, Pavoi, Depota, Rowta,

Dhemaji, North Lakhimpur, Majuli, Samaguri, Mariani

d. South Assam comprising of Panchgram, Dullavcherra Srikona and

Pailapool

e. Nagaland System comprising ofDimapur , Kohima and Mokukchung

SUB SYSTEM#2:Lower Assam comprising of BTPS, Agia, Dhaligaon, Barnagar, Nalbari,

Rangia, Sipajhar, Sarusajai, Kahilipara and Langpi

6.1.2 ISLAND B: Upper Assam comprising of NTPS, LTPS with Dibrugarh,

Nazira and Tinsukia

6.1.3 ISLAND C: comprising of Meghalaya System

6.1.4 ISLAND D:comprising of AGTPP(NEEPCO), Tripura and Mizoram

6.1.5 ISLAND E: comprising of Loktak (NHPC) and Manipur

6.1.1 Restoration of systems to be built up by utilizing power from ER

Sub-system #1 and sub-system #2 shall be restored in parallel after taking power from

Eastern Region. Simultaneously, all the generating Stations which have black-start

facilities are to be advised to bring their units as fast as possible, so that, islands can be

formed for early restoration of the system

6.1.1.1 Restoration of sub-system #1

Restoration of sub-system #1 consists of Main NER network, Arunachal,Central Assam,

South Assam and Nagaland. Restoration procedure of this sub-system is as follow:-

1) Power required for this sub system shall be taken from New Siliguri (ER) Sub-

Station to Bongaigaon (NER) Sub-Station through any one of 400 kV D/C New

SiliguriBongaigaon lines.

2) In case of delay in receiving power from New Siliguri (ER) Sub-Station, then the

following procedure shall be adopted :-


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Salakati (NER) Sub-Station shall receive power from Birpara (ER) Sub-Station

through any one of 220 kV D/C Birpara Salakati lines. Any one of 400 kV

Bus(s) at Bongaigaon Sub-Station shall be charged through 315 MVA ICT at

Bongaigaon Sub-Station. Again, Salakati Sub-Station shall charge any one of220 / 132 kV , 50 MVA ICT & shall extend power to Gelephu through 132 kV

S/C Saklakati Gelephu line.Load at Gelephu can be connected in co-

ordination with NLDC & Bhutan. Bus Reactors (at Annex III) at New Siliguri Sub-

Station and Bongaigaon Sub-Station shall be taken into service to contain

voltage. Bongaigaon (PG) Sub-Station shall extend power to Balipara (PG) Sub-

Station through any one of 400 kV D/C Balipara Bongaigaon lines. Any one of

220 kV Bus(s) at Salakati Sub-Station shall be charged through 315 MVA ICT at

Bongaigaon Sub-Station. If required, Tertiary Reactor at Bongaigaon (at Annex

III) may be taken into service to contain voltage.

Restoration of Arunachal Pradesh

3) Balipara (PG) Sub-Station shall extend power to Misa (PG) Sub-Station through

any one of 400 kV D/C BaliparaMisa lines and Shunt Reactors (at Annex III) at

Balipara and Misa Sub-Stations shall be taken into service to contain voltage.

Any one of 220 kV Bus(s) at Balipara Sub-Station shall be charged through any

one of 2 x 315 MVA ICT at Balipara Sub-Station. If required, Tertiary Reactor at

Balipara (at Annex III) may be taken into service to contain voltage. 132 kV Bus

at Balipara Sub-Station shall be charged through 2X50 MVA ICT at Balipara

Sub-Station. Balipara Sub-Station shall extend power to Khupi & Kimi Sub-

Stations of Arunachal through 132 kV Balipara Khupi - Kimi lines. Load at

Khupi & Kimi shall be connected in co-ordination with SLDC, Arunachal Pradesh.

4) Ranganadi (NEEPCO) Power Station can receive power from Balipara (PG)

Sub-Station through any one of 400 kV D/C BaliparaRanganadi lines. Any one

of 132 kV Bus(s) at Ranganadi Power Station shall be charged through any one

of 2X360 MVA ICT at Ranganadi Power Station. Ranganadi (NEEPCO) Power

Station shall extend power to SMS (Arunachal Pradesh) and Nirjuli (PG) Sub-

Stations through 132 kV S/C RanganadiSMS - Nirjuli (T Connection at SMS)

and shall extend power to Daporijo and Along (Arunachal Pradesh) Sub-Stations

through 132 kV S/C Ranganadi Ziro - DaporijoAlong lines. Shunt Reactors

(at Annex III) at Ranganadi Power Station shall be taken into service to contain


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voltage. Load shall be connected at SMS, Ziro, Daporijo and Along in co-

ordination with SLDC, Arunachal Pradesh.

5) 33 kV Bus at Nirjuli Sub-Station shall be charged through any one of 1X10+1X16

MVA ICT at Nirjuli Sub-Station. Nirjuli Sub-Station shall extend power to Itanagar(Arunachal Pradesh) Sub-Station through any one of four nos of 33 kV feeders.

Itanagar Sub-Station can also receive power from SMS Sub-Station through

Naharlagun (Arunachal Pradesh) Sub-Station. Load shall be connected at

Itanagar in co-ordination with SLDC, Arunachal Pradesh.

Restoration of Cental Assam6) Balipara (PG) Sub-Station shall also extend power to Gohpur (Assam) Sub-

Station through 132 kV S/C BaliparaGohpur line. Gohpur Sub-Station can also

receive power from Samaguri and Depota Sub-Stations through 132 kV

Samaguri Pavoi (Bishwanath Chariali) - Gohpur line and 132 kV Depota

Pavoi (Bishwanath Chariali) Gohpur line respectively. Load shall be connected

at Gohpur in co-ordination with SLDC, Assam. Balipara (PG) Sub-Station shall

extend power to Depota(Assam) Sub-Station through 132 kV Balipara Depota

line. Load at Depota shall be connected in co-ordination with SLDC, Assam.

Depota Sub-Station shall extend power to Rowta Sub-Station through 132 kV

Depota Rowta line. Load at Rowta shall be connected in co-ordination with

SLDC, Assam.

7) Gohpur (Assam) Sub-Station shall extend power to North Lakhimpur, Dhemaji

and Majuli Sub-Stations. Loads at North Lakhimpur, Dhemaji and Majuli shall be

connected in co-ordination with SLDC, Assam.

8) Ranganadi (NEEPCO) Power Station shall bring their machines if required and

synchronize with this sub-system. Otherwise, if the power received from Balipara

Sub-Station is delayed, Ranganadi Power Station shall black start one of their

three units and shall charge 132 kV Bus and extend power to SMS, Nirjuli & Ziro

Sub-Stations and wait for extension of power from Balipara Sub-Stations. If

possible they can also charge one circuit of 400 kV D/C Ranganadi Balipara

line for synchronization.

9) Gohpur Sub-Station can also receive power from Nirjuli (PG) Sub-Station

through 132 kV NirjuliGohpur line.


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Note : SLDC, Ass am and Arunach al Pradesh sh al l co-ordinate with NERLDC

before connect ing loads to their systems.

10) Any one of 220 kV Bus(s) at Misa Sub-Station shall also be charged through anyone of 2 x 315 MVA ICT at Misa Sub-Station after receiving power from Balipara

(PG) Sub-Station. If required, Tertiary Reactor at Misa (at Annex III) may be

taken into service to contain voltage.

11) Misa Sub-Station shall extend power to Samaguri (Assam) Sub-Station through

any one of 220 kV D/C MisaSamaguri lines. Shunt Reactors (at Annex III) at

Samaguri Sub-Station shall be taken into service to contain voltage. 132 kV Bus

at Samaguri Sub-Station may be charged through any one of 3X50 MVA ICT.

Load at Samagurishall be connected in co-ordination with SLDC, Assam.

12) Misa Sub-Station shall extend power to Byrnihat (Meghalaya) Sub-Station

through any one of 220 kV D/C Misa Killing (Byrnihat) lines. 132 kV Bus at

Byrnihat Sub-Station shall be charged through any one of 2X160 MVA ICT.

Byrnihat Sub-Station shall extend power to EPIP II Sub-Station through any one

of 132 kV D/C ByrnihatEPIP II lines. Load at EPIP II may be catered to in co-

ordination with SLDC, Meghalaya. EPIP II Sub-Station shall extend power to

EPIP I Sub-Station through any one of 132 kV D/C EPIP II EPIP I lines. Load

at EPIP I may be catere to in co-ordination with SLDC, Meghalaya and power

shall be extended progressively to Meghalaya power stations for synchronization

of machines. The related segregated operations will be carried out in close

coordination with NERLDC.

13) Byrnihat (Killing) shall extend power to Silchar sub-station through 400 kV S/C

SilcharByrnihat line, if voltage permits.

14) Mariani (Assam) Sub-Station can receive power either from Misa Sub-Station

through 400 kV S/C Misa Mariani line (Charged at 220 kV) or Samaguri

(Assam) Sub-Station through 220 kV S/C SamaguriMariani line (presently one

circuit is available). Shunt Reactors (at Annex III) at Mariani Sub-Station shall be

taken into service to contain voltage. Load at Mariani shall be connected in co-

ordination with SLDC, Assam.

15) Kopili (NEEPCO) Power Station shall receive power from Misa Sub-Station

through any one of 220 kV T/C Misa Kopili lines. Kopili Power Station shall

bring their machines by taking start up power from this sub-system and


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synchronize the machines with this sub-system. Otherwise, if the power received

from Misa Sub-Station is delayed, Kopili Power Station shall black start one of

four units and shall charge 220 kV Bus and extend power to Khandong Power

Station and wait for extension of power from Misa Sub-Stations.16) 132 kV Bus at Kopili Power Station shall be charged through 160 MVA ICT at

Kopili Power Station.

17) Kopili Power Station shall extend power to Khandong (NEEPCO) Power Station

through any one of 132 kV D/C Kopili Khandong lines. Khandong Power

Station shall bring machines, if required, by taking startup power from this sub-

system and synchronize the machines with this sub-system. Otherwise, if the

power received from Kopili Power Station is delayed, Khandong Power Station

shall black start one of three units and shall charge 132 kV Bus and extend

power to Haflong & Khliehriat Sub-Stations and wait for extension of power from

Kopili Power Station. If possible, they can also charge one circuit of 132 kV D/C

KopiliKhandong lines for synchronization.

Restoration of South Assam

18) Khandong Power Station shall charge 33 kV Bus through any one of

1X16+1X7.5 MVA Transformer. Khandong shall extend power to Umrangshoo

Sub-Station through 33 kV S/C of Khandong Umrangshoo line. Load at

Umrangsho shall be connected in co-ordination with SLDC, Assam.

19) Khandong Power Station shall extend power to Khliehriat (PG) and Haflong (PG)

Sub-Stations through any one of 132 kV D/C of KhandongKhliehriat lines and

132 kV S/C KhandongHaflong line respectively.

20) Khliehriat (PG) Power Station shall extend power to Badarpur (PG) Sub-Station

through 132 kV S/C Khliehriat- Badarpur line.

21) Badarpur Sub-Station shall extend power to Panchgram (Assam) Sub-Station

through 132 kV S/C Badarpur Panchgram line. Panchgram Sub-station shall

also receive power from Silchar through 132 kV Silchar Panchgram line.

Panchgram Sub-Station shall extend power to Srikona Sub-Station through 132

kV Panchgram Srikona line. Srikona shall extend power to Pailapool through

132 kV S/C SrikonaPailapool line. Load at Panchgram, Srikona and Pailapool

shall be connected in co-ordination with SLDC, Assam.


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22) This sub-system shall be synchronized with Island D at Badarpur (PG) through

132 kV S/C BadapurKumarghat line.

23) Again, Badarpur shall extend power to Silchar through any one of132 kV D/C

BadarpurSilchar lines. Silchar shall extend power to Srikona through any oneof 132 kV D/C Silchar - Srikona lines.

24) Silchar shall charge any one of 400 kV bus through any one of 400 / 132 kV 2

x200 MVA ICT. All the shunt reactors at Silchar sub-station (at Annex III) shall be

put into service to contain voltage.

25) Silchar shall extend power to Palatana Power station through any one of 400 kV

D/C SilcharPalatana Lines, if voltage permits. Before this, Palatana shall take

start up power through any one of 132 kV Udaipur Palatana and 132 kV

Surjyamani Nagar - Palatana of Tripura system (Island D) and shall synchronise

its unit.

26) This sub-system shall be synchronized with Island E at Badarpur (PG) through

132 kV S/C BadapurJiribam line.

27) This sub-system shall be synchronized with Island C at Khliehriat (PG) through

132 kV D/C KhliehriatKhliehriat lines.

28) Badarpur Sub-Station shall extend power to Kolasib (Mizoram) Sub-Station

through 132 kV S/C BadarpurKolasib line. Load at Kolasib shall be connected

in co-ordination with SLDC, Mizoram.

29) Kolasib Sub-Station shall extend power to Bairabi (Mizoram) Power Station for

survival/auxiliary power through 66 kV KolasibBairabi line.

30) Haflong (PG) Sub-Station shall extend power to Haflong (Assam) Sub-Station

through 132 kV S/C HaflongHaflong line. Load at Haflong shall be connected

in co-ordination with SLDC, Assam.

31) Mariani Sub-Station shall extend power to AGBPP (NEEPCO) through 400 kV

S/C Mariani AGBPP line (charged at 220 kV). AGBPP shall bring their

machines by taking start up power from this sub-system and synchronize the

machines with this sub-system. AGBPP shall extend power to Deomali

(Arunachal Pradesh) Sub-station through 220 kV S/C AGBPP Deomali line.

Load at Deomali shall be connected in co-ordination with SLDC, Arunachal

Pradesh.


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32) Misa (PG) Sub-Station shall extend power to Dimapur (PG) Sub-station through

any one of 220 kV D/C Misa Dimapur lines. 132 kV Bus at Dimapur Sub-

Station shall be charged through any one of 2X100 MVA ICT at Dimapur.

Restoration of Nagaland system33) Dimapur (PG) Sub-Station shall extend power to Dimapur (Nagaland) Sub-

Station through any one of 132 kV D/C DimapurDimapur line. Load at Dimapur

shall be connected in co-ordination with SLDC, Nagaland.

34) Dimapur (PG) Sub-station shall extend power to Kohima Sub-Station through

132 kV S/C Dimapur Kohima line. Load at Kohima shall be connected in co-

ordination with SLDC, Nagaland.

35) Kohima Sub-station shall extend power to Meluri Sub-Station through 132 kVS/C KohimaMeluri line. Load at Meluri shall be connected in co-ordination with

SLDC, Nagaland.

36) Meluri Sub-Station shall extend power to Khiphire Sub-Station through 132 kV

S/C Meluri Khiphire line. Load at Khiphire shall be connected in co-ordination

with SLDC, Nagaland.

37) 66 kV Bus at Khiphire Sub-Station shall be charged through any one of 3X6.5

MVA ICT at Khiphire Sub-Station.

38) Khiphire Sub-Station shall extend power to Likhimro Power Station through 66

kV KhiphireLikhimro line.

39) Dimapur (PG) Sub-Station shall also extend power to Doyang (NEEPCO) Power

Station through any one of 132 kV D/C Dimapur Doyang lines. Doyang Power

Station shall bring generation, if required and synchronize.Otherwise, if the

power received from Dimapur Sub-Station is delayed, Doyang Power Station

shall black start one of three units & shall charge 132 kV bus and extend power

to Mokakchung Sub-Station.

40) Doyang (NEEPCO) Power Station shall extend power to Mokokchung Sub-

Station through 132 kV S/C Doyang Mokukchung line. Load at Mokokchung

shall be connected in co-ordination with SLDC, Nagaland.

41) This sub-system may also be synchronized with Island E at Dimapur (PG)

through 132 kV S/C DimapurImphal line.

42) Dimapur (PG) Sub-Station can also receive power form Mariani Sub-Station

through 132 kV S/C MarianiGolaghatBokajan - Dimapur line.


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43) Mokokchung Sub-Station can also receive power from Mariani Sub-Station

through 132 kV S/C MarianiMokokchung line. Presently 132 kV S/C Mariani

Mokokchung line is under long outage. Early restoration of this line will help to

extend power to Mokokchung.

Note: SLDC, Ass am and Nagaland sh al l co-ordinate with NERLDC before

conn ect ing loads to their system

If ER power received by Misa Sub-Station is delayed then power shall be

taken from the following sources:-

i. From Island C, Khliehriat (PG) Sub-Station can receive power from

Khliehriat (Meghalaya) Sub-Station through any one of 132 kV D/C

KhliehriatKhliehriat lines.

ii. From Island C, Panchgram (Assam) Sub-Station can receive power from

Khliehriat (Meghalaya) Sub-Station through 132 kV S/C Khliehriat

Lumnsnong - Panchgram line.

iii. From Island D, Badarpur (PG) Sub-Station can receive power from

Kumarghat Sub-Station through 132 kV S/C BadarpurKumarghat line.

iv. From Island D, Kolasib Sub-Station can receive power from Aizawl Sub-

Station through 132 kV S/C KolasibAizawl line

v. From Island D, Panchgram (Assam) Sub-Station can receive power from

Dharmanagar Sub-Station through 132 kV S/C Dharmanagar -

Dullavcherra - Panchgram line.

vi. From Island E, Haflong (PG) Sub-Station can receive power from Jiribam

Sub-Station through 132 kV S/C HaflongJiribam line.

vii. From Island E, Dimapur (PG) Sub-Station can receive power from

Imphal(PG) Sub-Station through 132 kV S/C Imphal - Dimapur line.

6.1.1.2 Restoration of sub-system #2

Restoration of sub-system #2 consists of Lower Assam. Restoration procedure for this

sub-system is as follow:-

1) From sub-system #1, Salakati (PG) Sub-Station shall extend power to BTPS

(Assam) Sub-Station through any one of 220 kV D/C SalakatiBTPS lines.


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2) BTPS Sub-Station shall extend power to Agia (Assam) Sub-Station through 220

kV BTPS Agia line. Presently one circuit of 220 kV BTPS Agia is available.

Load at Agia shall be connected in co-ordination with SLDC, Assam.

3) 132 kV Bus at BTPS Sub-Station shall be charged through any one of2X80+1X160 MVA ICT at BTPS Sub-Station. BTPS Sub-Station shall extend

power to Dhaligaon (Assam) Sub-Station through any one of 132 kV D/C BTPS

Dhaligaon lines. Load at Dhaligaon shall be connected in co-ordination with

SLDC, Assam.

4) Dhaligaon Sub-Station shall extend power to Rangia (Assam) Sub-Station and

Barnagar (Assam) Sub-Station through 132 kV Dhaligaon Barnagar and 132

kV Dhaligaon Nalbari - Rangia lines. Load at Nalbari, Rangia and Barnagar

shall be connected in co-ordination with SLDC, Assam. 132 kV S/C Rangia

Barnagar line shall be closed.

5) Again, Rangia shall extend power to Motonga (Bhutan) through 132 kV Rangia

Motonga line. Gelephu can also receive power through Motonga.

6) Rangia Sub-Station shall extend power Sisugram (Assam) Sub-Station through

132 kV S/C RangiaSishugram line. Load at Sishugram shall be connected. If

required, Rangia Sub-Station shall extend power to Rowta Sub-Station too

through 132 kV RangiaSipajhar - Rowta & 132 kV RangiaRowta line. Load

at Sipajhar & Rowta may be connected in co-ordination with SLDC, Assam.

7) Agia (Assam) Sub-Station shall extend power to Sarusajai (Assam) Sub-Station

through 220 kV S/C Agia Sarusajai or 220 kV Agia Boko Sarusajai lines.

132 kV Bus at Sarusajai Sub-Station shall be charged through any one of 3X100

MVA ICT at Sarusajai. Load at Sarusajai & Boko shall be connected in co-

ordination with SLDC, Assam.

8) Sarusajai Sub-Station shall extend power to Kahilipara (Assam) Sub-Station

through any one line of four nos. of 132 kV SarusajaiKahilipara lines. Load at

Kahilipara shall be connected in co-ordination with SLDC, Assam.

9) Sarusajai Sub-Station shall extend power to Langpi (Assam) Power Station

through any one of 220 kV D/C Sarusajai Langpi lines. Sarusajai shall also

extend power to Jahawar Nagar(GIS) Sub-station through 220 kV Sarusajai -

Jahawar Nagar(GIS) line.


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10) Kahilipara Sub-Station can also receive power from Rangia and Sisugram Sub-

Stations through 132 kV S/C RangiaKahilipara line and 132 kV S/C Sisugram

Kahilipara line respectively.

11) Sarusajai Sub-Station can also receive power from Samaguri Sub-Station of sub-system #1 through 220 kV D/C SarusajaiSamaguri -II

Remark: SLDC, As sam shall co-ord inate wi th NERLDC/Meghalaya SLDC

before connect ing loads.

Note : If ER power intended to be received by this system is delayed then power

shall be taken/extended from the following sources :-

i. From Island C, Sarusajai Sub-Station can receive power from Umtru

(Meghalaya) Power Station through any one of 132 kV D/C Umtru -

Sarusajai lines.

ii. From Island C, Kahilipara Sub-Station can receive power from Umtru

(Meghalaya) Power Station through any one 132 kV D/C Umtru -

Kahilipara lines.


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6.1.2 Restoration of Island B

Restoration Island B consists of Upper Assam. Restoration of this Island could be done

by its own black-start facility as in follow:

1) NTPS (Assam) shall black-start and charge 66 kV Bus at NTPS. Load at NTPS

shall be connected in co-ordination with SLDC Assam. NTPS shall bring and

synchronize other units.

2) NTPS shall extend power to LTPS (Assam) through any one of 132 kV D/C

LTPSNTPS lines. LTPS shall bring generation and synchronize.

3) NTPS shall extend power to Tinsukia & Nazira (Assam) Sub-Stations through

any one of 66 kV D/C NTPS Tinsukia and any one of 66 kV D/C NTPS

Nazira lines respectively. Load at Tinsukia and Nazira shall be connected in co-

ordination with SLDC Assam.

4) 132 kV Bus at NTPS shall be charged through any one of 2X25 MVA ICT at

NTPS.

5) NTPS shall also extend power to Tinsukia (Assam) Sub-Station through 132 kV

S/C NTPS -Tinsukia line.

6) LTPS shall extend power to Dibrugarh (Assam) Sub-Stations through 132 kV

S/C LTPS Dibrugrah and 132 kV S/C LTPS - Nazira line. Load at Dibrugarh

shall be connected in co-ordination with SLDC Assam. 132 kV LTPS Nazira

line shall be closed.

7) This island shall be synchronized with sub-system #1 at Mariani (Assam) through

132 kV S/C LTPSMariani line.

Note: If Black start by NTPS is not possible, then start up power for this Island

shall be received from the following sources:-

i. From sub system #1, Tinsukia Sub-Station can receive power from

AGBPP through any one of 220 kV D/C Tinsukia AGBPP line andshall extend start up power to NTPS through 132 kV S/C Tinsukia

NTPS line.

ii. From sub system #1, LTPS can receive power from Mariani Sub-Station

through 132 kV S/C MarianiLTPS line.


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6.1.3 Restoration of Island C

Restoration of Island C consists of Meghalaya System. Meghalaya system can be built

up by its own black-start facilities. Restoration procedure for this Island is as follow:-

1) Umiam St I Power Station shall black-start and charge 132 kV Bus at Umiam St IPower Station. Umiam St III Power Station shall also black start and charge132

kV Bus at Umiam St III Power Station.

2) Umiam St I Power Station shall synchronize with Umiam St III Power Station at

Umium St III Power Station through any one of 132 kV D/C Umiam St I Umiam

St III lines. Umiam St I & III Power Stations shall bring and synchronize other

machines. Load at Umiam St III shall be connected in co-ordination with SLDC

Meghalaya.3) Umiam St I Power Station shall extend power to Umiam St II Power Station

through 132 kV S/C Umiam St I Umiam II line for survival/auxiliary power.

Umiam St II Power Station shall bring generation if required and synchronize.

4) Umiam St III Power Station shall extend power to Umiam St IV Power Station

through any one of 132 kV D/C Umiam St III Umiam IV line for

survival/auxiliary power. Umiam St IV Power Station shall bring generation if

required and synchronize.

5) Umiam St III Power Station shall extend power to Umtru Power Station through

any one of 132 kV D/C Umiam St III Umtru lines. Load at Umtru shall be

connected in co-ordination with SLDC Meghalaya. Umtru Power Station shall

bring generation if required and synchronize.

6) Umiam St I Power Station shall extend power to Mawlai and NEHU Sub-Stations

through 132 kV S/C Umiam St I Mawlai line and 132 kV S/C Umiam St I

Umiam - NEHU line respectively. Load at Mawlai, Umiam and NEHU shall be

connected in co-ordination with SLDC Meghalaya.

7) NEHU Sub-Station shall extend power to Khliehriat Sub-Station through 132 kV

S/C NEHU NEIGRIHMS - Khliehriat line or 132 kV NEHU Khliehriat line.

Load at Khliehriat and NEIGRIHMS shall be connected in co-ordination with

SLDC Meghalaya.

8) Khliehriat Sub-Station shall extend power to Lumsnong Sub-Station through 132

kV S/C Khliehriat- Lumsnong line.Load at Lumsnong shall be connected in co-

ordination with SLDC Meghalaya.


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9) Again, Power shall be extended to Leshka power station from Khliehriat

(Meghalaya) Sub-Station through 132 kV D/C KhliehriatLeshka lines.

10) This island shall be synchronized with sub-system #2 at Sarusajai (Assam) Sub-

Station and Kahilipara (Assam) Sub-Station through any one of 132 kV D/CUmtru Sarusajai lines or through any one of 132 kV D/C Umtru Kahilipara

lines.

11) This island shall be synchronized with sub-system #1 at Khliehriat (PG) Sub-

Station through any one of 132 kV D/C KhliehriatKhliehriat lines from Badarpur

(PG) via restored Island D.

Note: If Black Start by Meghalaya Power Stations is not possible then start up power

for this Island shall be received from the following sources:

i. From sub-system#1, Khliehriat (Meghalaya) Sub-Station can receive

power from Khliehriat (PG) Sub-Station through any one of 132 kV D/C

KhliehriatKhliehriat lines and extend power to Umiam St I and Leshka

Power Station through NEHU & Umiam Sub-Stations and 132 kV D/C

KhliehriatLeshka lines respectively, for brining generation.

ii. From Sub System #1, Khliehriat (Meghalaya) Sub-Station can receive

power from Panchgram (Assam) Sub-Station through 132 kV

Panchgram - LumsnongKhliehriat line.

iii. From Sub System #2, Umtru (Meghalaya) Sub-System can receive

power from Sarusajai (Assam) Sub-Station through any one of 132 kV

D/C Sarusajai Umtru lines and extend power to Umiam St III Power

Station through any one of 132 kV D/C Umiam St III - Umtru for brining

generation.

iv. From Sub System #2, Umtru (Meghalaya) Sub-Station can receive

power from Kahilipara (Assam) Sub-Station through any one of 132 kV

D/C Kahilipara Umtru lines and extend power to Umiam St III Power

Station through any one of 132 kV D/C Umiam St III - Umtru for brining

generation.

v. From Sub System #1, Umtru (Meghalaya) Sub-Station can receive

power from Killing (Meghalaya) Sub-Station through 132 kVD/CKilling

EPIPIIUmtru


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6.1.4 Restoration of Island D :

Restoration of Island D consists of AGTPP, Tripura and Mizoram. AGTPP and Tripura

System can restore its system by their own black start facilities. Restoration procedure

for this Island is as follow:-

Restoration of Tripura system

1) Rokhia (Tripura) Power Station shall black start and charge 66 kV Bus at

Rokhia Power Station. Load at Rokhia shall be connected in co-ordination with

SLDC, Tripura. Rokhia Power Station shall bring and synchronize other

machines.

2) 132 kV Bus at Rokhia Power Station shall be charged through 30 MVA ICT at

Rokhia Power Station.

3) Rokhia Power Station shall extend power to Agartala Sub-Station through any

one of 132 kV D/C RokhiaAgartala lines. Load at Agartala shall be connected

in co-ordination with SLDC, Tripura.

4) AGTPP (NEEPCO) shall black start one of its unit and charge 132 kV Bus at

AGTPP. AGTPP shall synchronize Tripura System through any one of 132 kV

D/C AGTPP Agartala lines. AGTPP shall bring and synchronize other

machines.5) Agartala Sub-Station shall extend power to Baramura Power Station through

132 kV S/C Agartala Budhjangnagar Jirania - Baramura lines. Baramura

Power Station shall bring generation and synchronize with this Island.

6) Budhjangnagar shall extend power to S Nagar through 132 kV Budhjangnagar -

S Nagar line.Then S Nagar sh

Documents

Restoration Procedure of NER Grid Nov-2013