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भारत सरकार

Government of India

विद्युत मंत्रालय

Ministry of Power

उत्तर के्षत्रीय विद्युत सवमवत

Northern Regional Power Committee

िंख्या: उ.के्ष.सव. ./ प्रचालन/106/01/2021/ सदनािंक: 09.07.2021

विषय: उत्तर के्षत्रीय विद्युत सवमवत की प्रचालन समन्वय उप-सवमवत की 184िी ं बैठक का

काययिृत|

Subject: Minutes of 184th OCC meeting of NRPC.

उत्ति के्षत्रीय सवद्युत समसत की प्रचालन मन्वय उप- समसत की 184वी िं बैठक सदनािंक

18.06.2021 को आयोसजत की र्यी थी। उक्त बैठक का कायगवृत्त उत्ति के्षत्रीय सवद्युत समसत की

वेब ाइट http://164.100.60.165/ पि उपलब्ध है। यसद कायगवृत पि कोई सटप्पणी हो तो कायगवृत

जािी किने के एक प्ताह के अन्दि इ कायागलय को भेजें |

184th meeting of the Operation Co-ordination Sub-Committee of NRPC was

held on 18.06.2021. The Minutes of this meeting has been uploaded on the NRPC

website http://164.100.60.165/. Any comments on the minutes may kindly be

submitted within a week of issuance of the minutes.

िंलग्नक: यथोपरि

( ौसमत्र मजूमदाि)

अधीक्षण असभयिंता (प्रचालन)

सेिा में,

उ.के्ष.वि.स. के प्रचालन समन्वय उप-सवमवत के सभी सदस्य

mailto:[email protected]

http://www.nrpc.gov.in/

http://www.nrpc.gov.in/

http://164.100.60.165/

http://164.100.60.165/

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कायगवृत:उ.के्ष.सव. .की प्रचालन मन्वय उप- समसत की 184वी िं बैठक पृष्ठ -2

उत्तर के्षत्रीय विद्युत सवमवत की प्रचालन समन्वय उप-सवमवत की 184िी ं बैठक

का काययिृत्त

184th meeting of OCC of NRPC was held on 18.06.2021 through video

conferencing.

खण्ड-क:उ.के्ष.वि.स. PART-A:NRPC

1. Confirmation of Minutes

Minutes of 183rd OCC meeting, held on 20.05.2021, was issued on 07.06.2021.

NRLDC representative requested for correction in para 10.5 of the minutes as

“Data from PMU at Kota has also been examined and no oscillation in voltage

was found” in place of “Data from PMU at Kota has also been examined and no

switching operation has been found”.

OCC confirmed the minutes with above correction.

2. Review of Grid operations of May 2021

2.1. Anticipated vis-à-vis Actual Power Supply Position (Provisional) for

May 2021

Reasons submitted by states for significant deviation of actual demand from

anticipated figures during the month of May 2021 are as under:

Uttar Pradesh

i. Most moderate weather of May in last 20 years. Low temperature,

frequent dust and thunderstorm.

ii. Actual energy consumption and peak demand was lower due to lockdown

by Uttar Pradesh Government to control COVID-19 cases.

Delhi

The demand has not picked up because of complete lockdown to control second

wave of COVID-19. Maximum temperature in May-2021 was 39.5 degree C.

whereas in May-2020 it was 47.6 and in May-2019 it was 46.2.

Punjab

Actual maximum demand/actual energy is less than the anticipated maximum

demand/energy on account of following:

i. Lockdown and curfew in the state of Punjab due to COVID-19.

ii. Relatively good rainfall in month of May-2021.

Rajasthan

The Energy consumption & Peak Demand w.r.t. Anticipated Energy requirement &

Peak demand have been decreased due to reduced commercial load caused

lockdown in state to control spread of COVID-19 pandemic and heavy storm & rain

observed due to “Tauktae” cyclone effect.


Himachal Pradesh

The Energy Requirement and Peak Demand remained on lower side during the

month of May, 2021 because lockdown was imposed in the state due to increase in

COVID - 19 cases.

Haryana


Peak demand was lower due to lockdown and pleasant weather in May’21.

Uttarakhand


Peak demand was lower due to lockdown and good rainfall in May’21.

OCC again expressed concern about non-participation of official from some

of the states and UTs in the meeting and requested all the utilities to

participate in the meeting.

2.2. Power Supply Position for NCR:

The Sub-Committee was informed that the NCR Planning Board (NCRPB) is

closely monitoring the power supply position of National Capital Region. Monthly

power supply position for NCR till the month of May, 2021 was enclosed in the

Agenda and same was discussed in the meeting.

No significant deviation in any of the states was observed.

2.3. The highlights of grid operation during May 2021 are as follows:

2.3.1. Frequency remained within the IEGC band for 74.49% of the time

during May 2021, which is lower than that of last year during same

month (May 2020) when frequency (within IEGC band) remained 76.69%

of the time. For further improvement, Utilities were advised to take

necessary action to improve the frequency regime by not changing

abruptly the loads at block boundaries and assuring primary response

from the generators.

2.3.2. Maximum and minimum load for the region during May 2021 were

52,797 MW (26.05.2021 at 22:35 hrs) and 25,125 MW (20.05.2021 at

04:00 hrs).

2.3.3. The average Thermal generation in May 2021 increased by

20.14% (85.84 MU/day) with respect to the corresponding month in the

previous year. The details are enclosed at Annexure-A.I (A).

2.3.4. The average Hydro generation in May 2021 decreased by 23.64%

(64.81 MU/day) with respect to the corresponding month in previous

year. The details are enclosed at Annexure-A.I (B).

2.3.5. The average Nuclear generation in May 2021 increased by 1.25

MU/day as compared to corresponding month in previous year. The

details are enclosed at Annexure-A.I (C).


2.3.6. The average Renewable generation in May 2021 increased by

13.70 % (9.29 MU/day) with respect to the corresponding month in

previous year. All utilities were requested to send the data for renewable

generation regularly. The details are enclosed at Annexure-A.I (D).

2.3.7. The new elements charged were discussed and the list is attached

at Annexure-A.I (E).

2.3.8. Long outage of generating units were discussed in detail and the

same is attached at Annexure-A.I (F).

2.3.9. Long outage of transmission line elements were discussed in

detail and the same is placed at Annexure-A.I (G) and all constituents

were requested to review the elements under long outage at the earliest.

3. Maintenance Programme of Generating Units and Transmission Lines

3.1. The maintenance programme of generating units and transmission lines for

the month of July 2021 was deliberated in the meeting on 17.06.2021.

3.2. Following shutdowns were also approved in the OCC meeting:

Element Reason for Shutdown Approved From Date

Approved To date

NRPC Remarks

Singrauli #7

(500 MW)

Boiler over haul,

Generator Bearing, LP

Turbine inspection.

20-Jun-2021

25-July-

2021

Subject to

revival of

Rihand units

2&4

250 MW

TEHRI HPS

- UNIT 3

Major Annual

Maintenance+ GT

Replacement work is

extended further due to

delay in transportation of

GT

21-Jun-2021

31-July-

2021

-

4. Planning of Grid Operation

4.1. Anticipated Power Supply Position in Northern Region for July 2021

The updated anticipated Power Supply Position for July 2021 is as below:

State / UT Availability / Requirement

Revised Energy

(MU)

Revised Peak (MW)

Date of revision

CHANDIGARH

Availability 200 360

No revision

submitted Requirement 210 450

Surplus / Shortfall -10 -90



Revised Energy

(MU)

Revised Peak (MW)

Date of revision

% Surplus / Shortfall

-4.8% -20.0%

DELHI


17-Jun-21 Requirement 4000 7950

Surplus / Shortfall 1282 0


32.1% 0.0%

HARYANA





11.3% 1.3%

HIMACHAL PRADESH





2.5% 1.0%

J&K and LADAKH


No revision

submitted

Requirement 1440 2420



50.7% 42.1%

PUNJAB


17-Jun-21




0.8% 0.4%

RAJASTHAN





10.6% 34.2%

UTTAR Availability 13330 23800 14-Jun-21



Revised Energy

(MU)

Revised Peak (MW)

Date of revision

PRADESH Requirement 13082 23800



1.9% 0.0%

UTTARAKHAND



Surplus / Shortfall -40 -20


-2.8% -1.0%

NORTHERN REGION





9.0% 7.5%

5. Information about variable charges of all generating units in the Region

5.1. Members were informed about the average delay in submission of data of

variable charges details on MERIT order portal during 19.05.2021 to 16.06.2021.

The average delay is given below:

5.2. It was highlighted that delay in data submission for UT of Chandigarh has

decreased but is still around 8 days. Delay in case of Uttarakhand has decreased a

bit. Significant delay has been observed in case of Punjab & Haryana for the above

duration.

5.3. All SLDCs were requested for timely submission of information on MERIT

Portal.

8.03

0.00 0.97 0.00 0.00

2.86

0.00 0.03 2.14

Average delay in data submission during 19-May-21 to

16-Jun-21


6. Submission of breakup of Energy Consumption by the states

6.1. The updated status on the submission of energy consumption breakup is

presented below:

State / UT From To

Delhi Apr-2018 Mar-2021

Haryana Apr-2018 Mar-2021

Himachal Pradesh Apr-2018 Apr-2021

Punjab Apr-2018 Mar-2021

Rajasthan Apr-2018 Apr-2021

Uttar Pradesh Apr-2018 Dec-2020

6.2. OCC forum again raised expressed concern on non-submission of energy

breakup data by Uttarakhand and UTs of J&K and Ladakh and Chandigarh

despite repeated reminders.

7. System Study for Capacitor requirement in NR for the year 2019-20

7.1. OCC forum was intimated that NRPC in its 48th meeting decided that the study

report for 2019-20 along with the guidelines for finding the capacitor

requirement at 11/33 kV level in NR would be submitted by CPRI. Accordingly,

CPRI have submitted the system study report on 24.02.2021 and thereafter

same was shared with the constituent states. The recommended capacitor

compensation, additionally required as per the report is 352MVAr. The report

has brought out the additional requirement of 137MVar and 215MVar

compensation for Punjab and J&K respectively. Moreover, empirical

relationship for capacitor requirement against voltage profile at 11 kV, based on

two configurations has been worked out in the report.

7.2. In the 45th TCC / 48th NRPC meeting, it was decided after the submission of

report for 2019-20 and the guidelines, the same would be studied by the same

sub-group who had earlier recommended for guidelines and foreclosure of the

contract. Based on Committee’s recommendations, NRPC Sectt. can process

the pending bills of Rs. 14 lakhs (Rs. 2 + 12 Lakhs), excluding taxes along with

foreclosure of the contract. Accordingly, submitted report needs to be

examined by the Committee.

7.3. In 181st OCC, forum decided that sub-group comprising of following officers

would study the report and submit the recommendation report within two

weeks:

• Ms. Bhaavya Pandey, AEE(O), NRPC Sectt.

• Ms. Suruchi Jain, Chief Manager, NRLDC

• Sh. Naveen Kumar AM(T), Delhi SLDC

• Ms. Sona Shishodia, Ex.Engineer, Rajasthan SLDC

• Sh. Pankaj Saxena, Ex.Engineer, UPPTCL

• Sh. Subhash Chand, XEN/works


• Sh. Mohit Walia, Punjab SLDC

• Sh. Rajesh Kumar, SE/PR, PSPCL Patiala

• Sh. Vinayak Shailly, EE, Uttarakhand

• Sh. Abhishek Puri, AE(E)

7.4. NRPC Sectt. had asked comments/observations on the CPRI report from all

the states via e-mail. Comment from Delhi was received. Rajasthan, HP,

Punjab, Haryana had submitted NIL comment. Comment from rest of the

members was not received.

7.5. In the 182nd OCC meeting, forum decided that a video-conferencing meeting

may be held by members of sub-group to finalize the comments latest by 30th

April, 2021 and compiled comments may be sent to CPRI for necessary

correction in the report.

7.6. In the 183rd OCC meeting, NRPC representative informed the forum that the

meeting of sub-group was held on 03.05.21 (delayed as per request of some

sub-group members due to health related concerns). Representative from

Rajasthan could not attend as she was suffering from COVID-19 while

Uttarakhand representative informed in the meeting that there is an acute

shortage of available officers at the time and they will agree to the remarks

made by NRLDC.

7.7. Based on the discussion of the meeting and comments submitted by UP, Delhi,

Punjab and HP, a compiled observation has been prepared. The same will be

sent to CPRI for corrections in final report. Further, PSSE file was requested

from CPRI as per request of all sub-group members in the meeting for better

understanding and the same has been shared with states.

7.8. NRPC representative requested for any other comments on the CPRI report, if

remaining, from any of the members. Sub-group committee member from

Rajasthan stated that since the CPRI report is for the year 2019-20, old data

needs to be collected and then values in the CPRI report would be checked. It

was further intimated that around 2-3 days time would be required for this task.

Rajasthan representative was requested to send their observation/comments

via e-mail to NRPC Sectt. at the earliest.

7.9. Forum decided that after receiving observations/comments from Rajasthan, the

compiled observations/comments may be sent to CPRI so that necessary

corrections may be done in the draft report.

7.10. In the meeting, forum was apprised that compiled comments has been mailed

to CPRI vide email dated 28th May’21 with a request to submit the corrected

report within two week’s time. Report from CPRI is awaited.

7.11. CPRI vide email dated 31st May’21 has communicated that majority of

comments are on the modeling of base case PSSE file. Since the file is given

by NRPC and CPRI has not modeled it so they are not in position to make any

comment on the accuracy & modeling of file.

7.12. Forum decided that a reminder may be sent to CPRI for submission of

corrected Report as two weeks has already passed.


8. Automatic Demand Management System

8.1. Forum was apprised that meetings on ADMS implementation roadmap have

been held with the officers of Haryana, HP and Punjab on 05.02.2021,

19.02.2021 and 05.03.2021 respectively. In these meetings, issues and

apprehensions on ADMS were discussed along with vital aspects like

addressing the commercial issues, basic architecture for scheme and funding

possibilities for the scheme.

8.2. As per request of states for DPR of any state that has got PSDF support for

ADMS, website link of PSDF Sectt. has been shared with Haryana, Himachal

Pradesh, & Punjab for accessing DPR.

8.3. Rajasthan SLDC updated that target date for ADMS implementation in the

state has been extended to Dec’21.

8.4. Uttarakhand SLDC stated that they will send nominations within 2-3 days.

8.5. SLDCs were requested for expediting the nominations pending from States.

9. Follow-up of issues from various OCC Meetings - Status update

9.1. The updated status of agenda items is enclosed at Annexure-A.II.

9.2. Forum was apprised that in 183rd OCC, it was highlighted that UFR

healthiness report of quarter Jan-Mar’2021 submitted by Rajasthan has no

dates of inspection during Jan’2021 to Mar’2021. All the inspection dates are

upto Dec’2020. Rajasthan SLDC was requested to cross check the dates

submitted in UFR healthiness report for quarter Jan-Mar’21 and reply on the

same.

9.3. Rajasthan SLDC vide its mail dtd. 24th May’21 has informed that as per

prevailing practice, submitted Q4 report is compiled report of test conducted

during Q1, Q2 & Q3 by respective Zone of Rajasthan and no test has been

conducted during Q4.

9.4. Rajasthan representative affirmed the reply sent via mail.

9.5. MS, NRPC expressed that UFR and df/dt relays are defence mechanism in

case of grid disturbances. Healthiness of it must be ensured in every quarter.

He asked Rajasthan representative whether this practice by Rajasthan is

approved by higher management.

9.6. On this, Rajasthan representative requested for some time to confirm it from

competent authority.

10. Condoning the forced Outages of 800 KV HVDC AGRA-BNC Pole-1/2 as forced

majeure due to stringent ROW at North Bengal, beyond control of

POWERGRID

10.1. In 183rd NRPC OCC meeting, PGCIL representative informed that the issue

was discussed in ERPC 178th OCC.


10.2. PGCIL representative informed that as per present status, the tree cutting in

the line span of 1293-1294 could not be carried out due to RoW issue which

leads to several flashover of Pole-2 of HVDC line. The same can be carried

out only after getting administrative support from district authority after the

completion of assembly election in West Bengal.

10.3. He added that Pole-I is having same capacity and comparatively free from

such constraints and proposed for operation of pole-I instead of pole-II till the

time the RoW issue gets resolved.

10.4. He highlighted that ERPC in its 178th OCC, felt that there is severe ROW

issue in the span of 1293-1294 which is beyond the control of licensee and

advised PGCIL to be in continuous touch with the District Authorities to

resolve the issue. OCC opined that till the resolution of ROW issues, Pole-1

may be frequently used upto its optimum limits as the clearance of Pole-1 is

better to avoid the unnecessary trippings of Pole-2 and requested ERLDC to

take up the issue with NLDC for un-interrupted and reliable pole operation of

HVDC BNC-Agra. Further OCC felt that the operation of HVDC BNC-Agra is

being looked/ controlled by NRPC/ NLDC the operational and availability

issues may be placed before NRPC/NLDC for final resolution.

10.5. In 183rd NRPC OCC, PGCIL requested that recommendations of ERPC may

please be ratified for optimum utilization of Pole-1 and condone the forced

outages of Pole-II until resolution of said ROW issue.

10.6. PGCIL representative further added that tree cutting was planned for

18.05.2021 but could not be done due to COVID-19 lockdown.

10.7. In 183rd OCC, forum advised PGCIL to submit its request along with all the

relevant documents to NRPC Sectt. for further action in this regard.

10.8. PGCIL submitted documents on 21st May, 2021. The same was examined

by NRPC Sectt. and PGCIL was asked vide mail dtd. 30th May’21 to follow

up with local administration of Jalpaiguri for firming up the date by which tree

cutting activity can be done.

10.9. NLDC was asked vide e-mail dated 31st May, 2021 to submit its comment

on the utilization of Pole-I upto its optimum limits and Pole-II under ready

mode in view of the total quantum of power flow between NR and NER

during March'21 -May’21 (or upto RoW issue resolution).

10.10. PGCIL informed that a meeting was held on 05.06.21 as per direction of

District Magistrate, Jalpaiguri but issue could not be resolved due to

unwanted demand of farmer/Land owners. SDO, Jalpaiguri has called next

meeting on 30.06.21.

10.11. PGCIL highlighted that this issue has been faced since 2019 and still the

matter is not getting solved.

10.12. MS, NRPC asked PGCIL representative whether highest officials like Chief

Secretary of West Bengal has been approached in this regard. He added


that a communication to Ministry of Power, CEA & POSOCO needs to be

done regarding this issue for expeditious resolution of the issue.

10.13. Forum decided that deemed availability on account of law and order problem

could be considered; however, NRPC Sectt may take up the matter with

MoP for expeditious resolution of the issue as the matter is of national

importance and line is of utmost importance for inter-regional exchange of

electricity.

10.14.

11. Procedure on Outage Planning for Communication System (Agenda by NRPC)

11.1. NRPC representative informed that CEA (Technical Standards for

Communication System in Power System Operations) Regulations, 2020 is in

force since 27.02.2020. Regulation 10 of the same provides for outage planning

of communication system and is reproduced below:

“Monthly outage shall be planned and got approved by the owner of

communication equipment in the concerned regional power committee,

as per detailed procedure finalized by the respective regional power

committee.”

11.2. In compliance of above regulation, a draft procedure on Outage Planning for

Communication System has been prepared by NRPC Sectt. and

comments/observation of forum is solicited.

11.3. NRLDC representative suggested that under para 5 (viii) name of the meeting

may be “Communication System Outage Co-ordination Meeting-NR” in place of

“Communication Equipment Outage Co-ordination Meeting-NR”. He stated that

NRLDC will review the procedure and will send its comments.

11.4. Haryana representative suggested that the draft procedure may be transferred

to TeST committee for discussion.

11.5. MS, NRPC stated that although communication outage may be looked after by

OCC, this draft procedure may be sent to TeST committee for vetting.

11.6. Forum decided that all the stakeholders may send their comments on the draft

procedure latest by 30th June’21. Thereafter, the draft procedure will be sent to

TeST committee for vetting.

12. Installation of Special Protection Scheme at 400 kV sub-station Lucknow (PG)

and Sohawal (PG) (Agenda by UPSLDC)

12.1. UP SLDC informed that assessment of Total Transfer Capability (TTC) of UP

transmission Network for Peak Season (2021) has been conducted. During

the calculation of TTC, N-1 Non-Compliance issue has been observed at

400kV s/s Lucknow (PG) & Sohawal (PG).


12.2. To ensure secure & reliable grid operation and to utilize UP Transmission

Network capacity optimally, augmentation at these substations is required.

To avoid blackout incident at above substations of M/s PGCIL, System

Protection Scheme may be planned to take care of overloading of ICTs.

12.3. UP SLDC requested that PGCIL may be advised to install SPS at above

mentioned substations at the earliest.

12.4. After discussion, forum decided that UP SLDC may submit proposal for SPS

at 400kV s/s Lucknow (PG) & Sohawal (PG). The SPS logic may be

discussed in the OCC meeting and thereafter, it can be placed before

TCC/NRPC for approval.

13. Frequent line tripping and high voltage fluctuation of HVPNL 400 KV line

leading to JPL unit tripping (Agenda by JPL)

13.1. Mahatma Gandhi Thermal Power Plant (MGTPP) of Jhajjar Power Limited

(JPL), Haryana informed that on 30.05.2021 at 15:58:14 Hrs., fault occurred

in R Phase of 400 KV JPL to Kabulpur Circuit II, with distance of 11.8 KM

from JPL end and fault current 11.23 KA. Due to this, suddenly 400 KV

circuit breaker opened in auto recloser mode and Unit#1 Generator

(operating at 573 MW) tripped.

13.2. On 29.04.2021 at 18:58:28 Hrs, the same 400 KV JPL to Kabulpur Circuit II

also got tripped on distance protection and after clearance from Kabulpur

substation, line was charged.

13.3. On 27.05.2021 at 13:30 Hrs, 400 KV JPL-Dhanoda circuit -2 tripped on DTT

(Direct Trip). PLCC Channel II is faulty and not in service till date.

13.4. JPL highlighted that they are facing frequent voltage fluctuations in Kabulpur

lines. JPL requested to HVPNL to investigate the cause of these incidents

and take the necessary remedial measures.

13.5. SLDC Haryana stated that the custodian of all lines have been directed to

maintain their lines.

13.6. NRLDC representative stated that details of Disturbance Recorder may be

shared with NRLDC & Haryana.

13.7. After discussion, forum decided that Generation and Transmission utility may

co-ordinate for cross-checking of protection settings.

14. Frequent load ramp up/down within a short span of time (Agenda by JPL)

14.1. JPL representative informed that many a time schedule is given by SLDC

for one time block Technical Minimum load and again Load ramp up to full

load. It creates disturbance/fluctuation (i.e. Main steam temperature and

pressure) which result in Boiler metal temperature exceeding the limit, cyclic

heating and cooling of steam turbine. This is major reason for boiler tube

leakage and on longer run, it impacts reliability of both boiler and turbine.


14.2. Haryana SLDC stated that it always gives schedule as per technical

capability of generator considering merit order. For a 660 MW unit, 45

MW/block ramp rate is given.

14.3. NRLDC representative stated that extant regulations mandates for 1% per

minute ramp rate and there is no mention of limitation on number of ramp up

and ramp down of machine.

14.4. SE (O) stated that JPL could have first discussed this issue bilaterally with

Haryana before bringing the agenda before OCC. He also highlighted that

JPL has not submitted any supporting data regarding this issue.

14.5. After discussion, OCC decided that JPL may submit supporting documents

of the issue to Haryana SLDC for examination.

15. Generation loss to NJHPS and RHPS due to Grid Constraints on 12.06.21

(Table Agenda)

15.1. SJVNL representative informed that on 12.06.21, NJHPS and RHPS were

generating at their full capacity and all outgoing lines i.e. NJ-PKL-1, NJ-

Gumma-II, NJ-Rampur-1&2 were intact.

15.2. From 02:48 hrs to 3:35 hrs, Auto Reclosure event occurred in all the

outgoing lines one after the other and resulted in tripping of One unit of

NJHPS & subsequently one unit of RHPS due to SPS-case 1 and the same

was revived at 03:38 hrs.

15.3. At 03:35 Hrs Karcham Wangtoo- Abdullapur-II line tripped and resulted in

increase in line loading at NJHPS end. After the above tripping of KWHEP

line, NRLDC instructed NJHPS control room to watch the line loading in all

the outgoing line and to reduce its generation in order to keep line loadings

in safe zone. Responding to the pre- instruction of NRLDC, NJHPS and

RHPS reduced their generation to avoid SPS operation. Under agreed

scheme of SPS, in case of increased load on lines at NJHPS end, one unit

of KWHEP is to be back down. In this case, it is not evident that KWHEP

has also been asked to back down their generation or not.

15.4. At around 05:24 Hrs, Karcham Wangtoo- Abdullapur-I line tripped and

resulted in flow of the entire load of KWHEP via NJHPS resulting in

overloading at NJHPS outgoing lines and subsequently tripping of one unit

of NJHPS and RHPS at 05:25 hrs due to SPS-case1 and the unit was

revived at 05:53 hrs.

15.5. Further, at 08:26 hrs, KWHEP charged Karcham Wangtoo-Abdullapur-I line

but breaker could not hold, resulting in tripping of one unit of NJHPS and

RHPS at 08:26 hrs due to SPS- case 1 and the Unit was revived at 09:05

hrs.

15.6. It is submitted that all the outgoing lines from NJHPS were charged

throughout the above period and the fault was there in Karcham-

Abdullapaur-I&II circuits. Prior to the above events, NJHPS, RHPS and


KWHEP were generating at their full load capacity. As the lines tripped at

KWHEP end, KWHEP full load evacuation was being made via NJHPS lines

causing increased load and tripping.

15.7. Since this is a high flow season, instruction of backing down of generations

to NJHPS & RHPS and operation of SPS resulted in spillage of water and

loss of Energy around three (3) MU.

15.8. In such cases, the SPS protocol may be revisited and the generating entity

having full capacity to evacuate power may not be asked to reduce the load.

It is quite rational to ask the entity having constraints of transmission line to

backdown their generation first and subsequently other generators may

reduce the generation.

15.9. NJHPS representative added that when two outgoing circuits originating

from Karcham towards Abdullapur were under outage, not less than two

Generating Units of KWHWP should have been stopped so that they could

inject not more than 500 MW, whereas only one Unit of KWHEP was

stopped and they were injecting around 850 MW, whereas NJHPS was

asked to reduce their Generation even though all their Power Evacuation

Capacity was intact. This resulted in spillage of water and loss Energy at

NJHPS/Rampur end which could have been avoided.

15.10. NRLDC representative stated that whole complex is taken in consideration

by operator and not a single generator. On the day in discussion, the

backing down was on pro-rata basis. Karcham unit was also instructed to

back down.

15.11. On the event of SPS operation, NRLDC representative stated that SPS logic

at Jhakri end may be revisited. Fault current should not trigger SPS. A delay

of 1500 milli-seconds may be done in logic.

15.12. Forum decided that fault current may not trigger SPS, therefore necessary

modifications in SPS protection may be done.

16. Singrauli Ramp rate assessment for FY 2020-21 (Table Agenda)

16.1. Representative of NRPC informed that as per Tariff Regulations 2019, the

ROE of generating stations has been linked with the ramping capabilities of

the generators w.e.f. 01.04.21. In case a generator is unable to demonstrate

a ramp rate of 1%, its ROE is decreased by 0.25%. NLDC has come up with

a detailed procedure to calculate the ramping capability of generating

stations in accordance with the Tariff Regulations.

16.2. During FY 2020-21, Singrauli STPS declared a ramp rate of 1% of its

declared capacity rather than 1% of ex-bus capacity of machines on bar

from 01.04.21 to 28.05.21. The same was corrected to 1% of ex-bus

capacity of machines on bar w.e.f 29.05.21. However, due to reduced

declaration in the months of April and May, the number of time blocks in

which ramp rate declared by Singrauli STPS was at least 1% was calculated

to be 83.33% during FY 2020-21, which is below the threshold of 85%

required for full recovery of ROE.


16.3. Representative of NTPC informed that the ramp rate Regulations had come

into effect from April 2020 during corona period. There was some error in

interpretation of the regulations at their end which resulted in incorrect ramp

declaration initially in the WBES portal. The error was corrected

subsequently, and ramp rate of 1% of ex-bus capacity of machines on bar is

being declared from now. Since the mistake is bonafide, NTPC requested

that it may be allowed to recover full ROE for Singrauli STPS for FY 2020-

21.

16.4. It was pointed out that as per detailed procedure, actual ramp rate could be

checked in case number of ramping instructions given to a particular plant

exceed 90 during a month (1080 during a year). However, Singrauli only got

ramping instructions in 170 time blocks during FY 2020-21. In those time

blocks, it achieved the desired ramp rate in 45% of the time blocks.

However, since sufficient opportunities to demonstrate the ramping

capability were not given to the plant, ramping capability has to be

calculated as per the declared ramp rate of the plant, as per detailed

procedure given by NLDC.

16.5. MS, NRPC stated that the request of NTPC seemed genuine, however

since beneficiaries of Singrauli TPS have to bear the fixed cost of the plant,

they may state their observations, if any. No observations were received

from the beneficiaries during the meeting. OCC urged beneficiaries of

Singrauli TPS to state any observations/objections to the request of NTPC

within 7 days via mail to [email protected]/[email protected]. In case no

objections are received, NTPC may be required to recover full ROE for

Singrauli.

17. Interest Computation for delayed DSM charges payment for FY 2019-20

and FY 2020-21 (Table Agenda)

17.1. NRPC representative informed that during FY 2019-20, there was some

discrepancy in Net schedule computation of Haryana for the week

04.11.2019 to 10.11.2019 (WK-32) due to which the DSM charges for

Haryana were calculated as 26,88,17,828/- (account issued on 21.11.19,

due date 01.12.19). Haryana conveyed that there has been some

discrepancy via mail dated 27.11.2019. Subsequently, the DSM account for

week-32 was revised and issued along with DSM account for the week

11.11.2019 to 17.11.2019 (WK-33) on 28.11.2019 (due date 08.12.2019).

17.2. The differential amount between the initial bill ( Rs 26,88,17,828/-) and

revised bill (Rs 54,43,695/-) for week-32 comes out to be Rs 26,33,74,133/-

(receivable). This was clubbed together with the DSM charges for week-33

i.e. Rs 48,35,448/- (payable), hence net receivable for week-33 was

calculated as Rs. 25,85,38,685/- (due date 08.12.2019).

17.3. As per billing philosophy in operation the bills generated against Haryana

were Rs 26,88,17,828/- (payable, due date 01.12.19) and

Rs 25,85,38,685/- (receivable, due date 08.12.2019). Against the said bills,


Haryana made payments of Rs.54,43,695/- on 02.12.2019 and

Rs.48,35,448/- on 09.12.2019.

17.4. This lead to an interest liability of around Rs 5 lakh on Haryana for FY 2019-

20. Haryana vide mail dated 09.12.2020 requested for waiving off LPS on

DSM charges since the high DSM charges were calculated due to

discrepancy in computation of net schedule of Haryana.

17.5. A similar issue is also being faced while calculating delayed interest charges

during the FY 20-21. There was discrepancy in DSM charges for week 18 (

27-07-20 to 02-08-2020) issued on 17-08-2020 for the states of Chandigarh,

Haryana, Himachal Pradesh, Punjab & Rajasthan due to the error in the

meter data of irrigation wing. As per the request of the state, NRPC issued

the revised account of week 18 immediately along with DSM account of

week 19 on 20-08-2020.

17.6. Chandigarh, Haryana, Himachal Pradesh & Punjab paid the net amount of

the accounts issued for Week 18(revision) & Week 19 (without including

differential) whereas Rajasthan paid the amount as per the account of Week

18(original) and Week 19 (including differential). Hence, there would be

some delay payment interest for the above period for Chandigarh, Haryana,

Himachal Pradesh & Punjab.

17.7. Since the delayed interest charges are on account of error in calculation,

members may consider waiving off the interest charges.

17.8. After discussion, OCC approved the proposal of waiving of interest charges

for Haryana, Punjab, Chandigarh and Himachal Pradesh for late payment of

DSM charges for the WK-32 of FY 2019-20 and WK-18 of FY 2020-21.

खण्ड-ख: उ.के्ष.भा.पे्र.के. Part-B: NRLDC

18. Grid operation related issues

(i) High loading of 400kV Bhinmal-Zerda

NRLDC representative stated that at the time of high RE generation in Rajasthan

including high internal generation/low demand in Rajasthan alongwith with high

demand/ multiple unit outages in Gujarat, the flow on Bhinmal-Zerda (Twin Moose)

has been observed to be 600MW to 700MW (in general between 13:00hrs to about

17:00hrs) for the few days. In these cases, under N-1 contingency of 400kV

Kankroli-Zerda, the loading of 400kV Bhinmal-Zerda is likely to exceed the thermal

rating.

It was deliberated that although actions such as varying power order of Mundra-

Mahendragarh and increasing internal generation of Gujarat are being carried out in

real-time, it is necessary that Rajasthan also analyses the reasons for high loading

of 400kV Bhinmal-Zerda and suggest possible measures to relieve loading of this

line. Being an inter-regional line it becomes important that loading of line is strictly

monitored during real-time and appropriate actions are taken by all concerned

callto:18(%2027-07-20

callto:18(%2027-07-20


especially considering the growth of renewable generation in Jaisalmer-Barmer

area of Rajasthan. Feedback related to same is also being submitted by

NRLDC/NLDC to CTU/CEA.

In the meeting, Rajasthan representative informed that the line is connected to

ISTS station and they have little control on power flow as there is likely high load

connected near Zerda in Gujarat resulting in high flow of lines. Moreover, Rajasthan

STU representative also informed that due to ROW issues and non-award of

clearance due to Great Indian Bustard sanctuary in the area as per Supreme court

order, it is difficult to plan and develop new lines in this area.

OCC appreciated the concern raised by Rajasthan SLDC and STU representatives

and suggested that the feedback should be submitted to CEA/CTU/STU and other

agencies responsible for transmission system planning so that with increase in

renewable generation in Rajasthan, safe loading of line may be ensured. Further,

since control of power flow through this line involves coordination between two

different regions, the matter comes under the purview of NLDC. It was discussed

that conductor change of 400kV Bhinmal-Zerdaline from Twin Moose to higher

capacity may also be explored.

(ii) Load crash on 01.06.2021

NRLDC representative stated that on 01.06.2021, number of element tripping and

huge reduction in demand were reported in Northern region. The load of NR started

reducing after 21:45hrs on 31.05.2021, dropping by 18.2GW in the span of 6hrs

33minutes. At 04:18hrs of 01.06.2021, load of NR was minimum and thus load

started picking up after 06 hours 33 minutes from the start of load crash. Average

demand crash of 14.38 GW was observed during inclement weather conditions

(21:45hrs of 31st May 2021 to 04:18hrs of 01st June 2021) as compared to the

previous day.

It was seen that frequency continued to remain above the band for most of the time

due to under drawl, as is visible from the frequency plot. The frequency remained

above IEGC band continuously during the night hours.

As reported, stormy weather condition prevailed in Northern region leading to the

tripping of multiple elements on various faults as well less demand in Northern


region. Due to this unprecedented condition, there was heavy under drawl by UP,

Rajasthan, Haryana, Punjab and Delhi.

Total 42 no. of 400 and above voltage level elements (lines and ICTs) tripped and

total 38 no. of 400 and above voltage level lines were manually opened on high

voltage including four multiple element tripping (GI-2 category) during thunderstorm

and bad weather on early morning hours of 01st June 2021.

Several actions including warning/alert messages were issued to NRLDC/SLDC

Control Centres. The generation of ISGS thermal stations was backed down.

Instructions were issued for backing down of generation in state generating station

of Punjab, Haryana, UP, Rajasthan, Uttarakhand, Delhi and Chandigarh in order to

maintain the frequency within the band. RRAS down was given by NLDC. SLDCs

assessed the movement of thunderstorm/dust storm through RADAR system and

reduced their state control area generation.

Punjab & UP reduced their hydro generation by 150MW & 400MW respectively.

However delayed backing down of generation was observed in Punjab and

Haryana. SLDC Haryana and Punjab needs to ensure quick backing down of

generation within their state control area during such events.


Punjab SLDC representative informed that due to sudden demand crash, only

option left is to surrender power, because plants are generally not shutdown

because demand picks up quickly after bad weather. System operators are already

taking necessary actions in real-time. It was also mentioned that due to audit issues

SLDC is sometimes reluctant to sell power in real-time market.

NRLDC representative suggested that Standard Operating Procedure may be

developed by Punjab SLDC so that in case of such load crash events actions are

taken in accordance with SOP. Few instances highlighting the benefits of selling

power in real-time market including financial benefits may be presented to higher

management which shall help in future actions.

NRLDC representative stated that actions are taken at SLDC level, but there is still

scope for improvement. Only based on analysis of previous events, better actions

can be planned in future. Utilities were requested to submit the detailed report on

load crash within 5 days considering the following points:

• Load Crash (in MW) in the State

• Analysis of Thermal Generation backing down in the state (till technical

minimum or not, if not than reason of the same needs to be discussed)

• Analysis of fast ramping down of state generation during reduction in

demand met.

• Reason of large deviation from the schedule

• Line tripping & tower collapse (132 kV and above)

• Line manually opened on high voltage in state Grid

• Future remedial measures (Improvement in action taken for future)

However, such specific report has not been received from any of the constituents.

It has been discussed in various OCC/one-to one meeting with SLDCs to have a

separate Weather monitoring screen at SLDC control room. The dedicated screen

would help in continuous monitoring of weather and hence help in taking proactive

decisions in real time system operation.

It is observed that during weather-initiated load throw off, some generating units

under state control area are ramped down upto only 70-75% of their capacity. It has

been previously deliberated in several OCC/TCC/NRPC meetings that states shall

ensure that generators are backed down upto 55% or 60% (if some design issue).

SLDCs were also advised to approach SERC in this regard.

Rajasthan SLDC representative informed that SERC is likely to revise the technical

minimum limits of generator in next state grid code revision.

(iii) Long outage of transmission elements/ generating units

Reasons and revival date for elements under long outage are being discussed

regularly in OCC meetings. Update on the status of these elements as informed in

184 OCC meeting is mentioned below:

• UPPTCL representative informed that revival of 400kV Bareilly-Unnao ckt 1

and ckt 2 is expected by 20th June 2021.


• POWERGRID NR-3 representative informed that CEA inspection points are

pending for 220kV bays at Shahjahapur(PG)

• UPPTCL representative informed that

• 315 MVA ICT1 at Muradnagar is to be replaced by 500MVA ICT

(expected by Oct 2021)

• 500 MVA ICT2 at Noida sec 148 is expected by Sep 2021

• 315 MVA ICT1 at Orai(UP) is expected by Jul 2021

• BBMB representative informed that Bhakra Unit-3 and Dehar unit-3 are

expected to be revived in July 2021 and remaining units are expected to be

revived in June 2021.

• NTPC representative informed that Rihand Unit-2 is expected to be revived

by 20th June 2021.

All utilities were requested to make it a practice to update status of elements

under long outage in the NRLDC outage software portal. Utilities were

requested to take necessary actions to revive elements which are under long

outage.

(iv) Information about new transmission elements/ generating units to be

commissioned in next 45 days

In 176th OCC meeting, it was discussed that first time charging procedure is not

being diligently followed by some entities. The necessary documents are often

submitted to NRLDC at the last minute, with very little time available for verification

before the planned date of energization. Subsequently, there is vigorous persuasion

with NRLDC for issuing the code for charging. In the meeting it was also requested

that utilities should inform about new elements expected to be charged in the next

one month in advance in OCC meeting. This information would be helpful in

carrying out studies, assessment of SPS requirement/modification etc in time.

UP SLDC shared following list of elements expected to be charged within the next

45 days:

1. 400 kvBadaun-Sambhal line.

2. 220kV Sambhal-Chandausi LILO @ 400kV Sambhal

3. 220kV Sambhal-Gajraula LILO @ 400kV Sambhal

4. 132kV Chandausi-Bilari LILO @ 400kV Sambhal

5. 132kV Bisauli-Babrala LILO @ 400kV Sambhal

(v) Impact of cyclone Tauktae in Northern region

In the meeting, it was deliberated that Cyclone Tauktae struck the western coast of

India on 16-18 May 2021. NRLDC had issued an advisory for Northern region

constituents to remain alert especially Rajasthan control area. All constituents were

asked to monitor weather conditions closely and take necessary actions to ensure

load-generation balance and secure operation of grid.

Plot suggesting intensity (wind speed) of both the cyclones Tauktae and Yaas

(cyclone Yaas made its landfall on 26-05-21 on the Eastern coast of India) as


obtained from the weather monitoring system at NRLDC, are given below. As clear

from the plot, intensity of Yaas was lower compared to Tauktae.

Along with forecast of wind speed, the trajectory of cyclone along the coastline was presented. It was highlighted that with this tool it is possible to view and highlight the transmission elements which were most likely to be impacted during cyclone. Accordingly, warning messages were issued to substation officials asking them to be extra vigilant during these times.

Live cyclone monitoring was being carried out at RLDC/NLDC control centers monitoring the path of cyclone.


The change in weather due to cyclone resulted in rainfall, windstorms in Northern region and as a result demand of several Northern region states was lower compared to previous days. The demand plots of Rajasthan, Haryana, Delhi and UP are provided below.

Rajastha

n

Haryana

Del

hi

UP


However, with cooperation from all stakeholders, Northern region was able to face the post-cyclone weather impacts ensuring grid security and reliability. This is for kind information of OCC members.

(vi) Coordination and communication of various activities such as first time

charging/outage coordination for TBCB projects

In the meeting, it was deliberated that many transmission projects had been

awarded by Govt. of India through TBCB route. In most of the cases, it is observed

that these projects are generally owned by some existing parent companies.

In this regard it was clarified that there are some mandatory requirements which

need to be complied by TBCB projects. They are as follows-

1- Registration as a user of NRLDC ( in case of regional entity)

2- Submission of registration fees.

3- Submission of copy of transmission licensee issued by CERC.

4- Submission of copy of connection agreement.

5- Submission of copy of Certificate of Incorporation.

6- Furnishing bank account details/PAN No./TAN No. and GSTIN

7- Submission of application as per Appendix-IV in line with CERC Regulation

2019.

8- Furnishing Copy of authorisation of authorised signatory.

Recently, request for outage and first time charging coordination was made by

PGCIL for 765kV Phagi-Ajmer-D/C line, 3*80 MVAR Bus Reactor and associated

elements. Even though all the documentation was done by PGCIL, it came to the

knowledge of NRLDC that above project is a TBCB project and the actual

transmission licensee had not complied with the formalities.

Utilities were advised to ensure that documents are submitted and formal

procedures are duly complied with by TBCB project companies as per

regulatory requirements well within timelines.

(vii) Switching operation without NRLDC code

The issue had already been deliberated in 175th, 178th and 179th OCC meetings.

In the meeting NRLDC expressed concern about such repeated violation of IEGC

as well as procedure agreed in Operating procedure document. NRLDC has

already sensitized the NR utilities in this regard, vide letters:

• NRLDC/SO-I/ dtd. 27.10.2020

• NRLDC/SO-I/151/1088-1090 dtd. 10.12.2020

• NRLDC/SO-I/151/1134-1136 dtd. 07.01.2021

• NRLDC/SO-I/151/dtd 08.06.2021

It has already been deliberated that before taking any element under outage, it is

essential to inform NRLDC, since taking the element out may result in increased

flows on parallel paths and the substation personnel does not have the holistic

scenario/ load-flows of the grid. Unilateral switching operation of Grid elements by


transmission licensees without proper coordination/intimation may lead to any

disturbance/ cascade tripping in the transmission network and may lead to grid

incidents/Disturbances which is not warranted and in such a case the concerned

transmission licensee/constituent shall be solely responsible for the same.

IEGC clause was once again quoted and utilities were asked to make sure that

necessary precautions are taken so that there is no violation of IEGC clause 5.2(b).

All NR constituents were once again requested to avoid unilateral switching

operation of Grid elements in future in the interest of smooth and reliable Grid

operation. Members agreed to honour the decision of OCC.

(viii) Summer/ Monsoon preparedness

Measures to be adopted by NR constituents for summer preparedness were discussed

in detail in 181 OCC Meeting (Mar'21). Areas discussed include: maintenance of

reserves, furnishing of coal stock position, portfolio management, tower strengthening

work and availability of ERS, Reactive power management, ensuring healthiness of

defense mechanisms, telemetry issues etc.

In last three OCC meetings, constituents were requested to provide feedback on the

actions being taken by them for ensuring safe and reliable grid operation during

upcoming next few months through email.

Constituents were requested to provide their feedback in this regards related to

actions taken by them for summer/monsoon preparedness.

(ix) Maintaining frequency profile of the grid

In last several OCC meetings, SLDCs were asked to take following necessary actions

to minimize large fluctuations during real-time.

• Close monitoring of weather forecasts from IMD which is available at weather

portal for power sector

• Accurate load forecasting

• Backing down intra-state generation

• Buying/ Selling power in real-time market

• Surrendering ISGS power timely

• Avoiding manual opening of feeders in coordination with DISCOMs

• Ensuring generating machines are put under RGMO / FGMO so that action of

Governors assists in maintaining frequency profile during frequency change

events.

In spite of such persuasion, it is observed that there are frequency excursions

especially at hourly boundaries.


Frequency profile for 01.06.2021 showing hourly excursions

The frequency profile for the month of May-2021 and state-wisedrawl/generation/

consumption/UI/shortage MUs was attached as Annexure-III of agenda.

All SLDCs were once again asked to take following necessary actions to minimize

frequency excursions during real-time.

• Improving accuracy of load forecasting

• Backing down intra-state generation

• Buying/ Selling power in real-time market

• Surrendering/ Requesting ISGS power timely

• Avoiding manual opening of feeders in coordination with DISCOMs

(x) Intermittent Data from State-Sub-Stations

In the meeting it was deliberated that telemetry data from many 400/765KV

substations is intermittent. The importance of valid SCADA data requirements for

the smooth grid operations had been emphasized many times in the past.

Decisions in real-time are taken by shift engineers based on real-time data

available to Control room. Further, good telemetry is also essential for successful

execution of State Estimator/Energy Management System (EMS).

Since proper telemetry is intermittent from many substations it has impact on

successful running of state estimator. Correct telemetry is essential for running

State Estimator/ Contingency Analysis in EMS, Better SE output will aid in

situational awareness of the system operators.

List of Sub-Stations presented in the meeting is given below.

Station Name Constituent % Availability May-21

MUNDKA DTL 67


CCGTB 91

BAWANA 95

BAMNAULI 95

HARSHVIHAR 95

BASPA

HP

51

WANGTU 88

SAINJ 91

DHANONDA

HVPNL

81

NAWADA 90

KIRORI 94

MUKTSAR 400kV

PSTCL

85

NAKODAR 93

TALWANDI SABO 95

SRINAGAR PTCUL

0

KASHIPUR 400kV 88

BIKANER 400kV

RRVPNL

34

ANTA 70

KALISINDH 80

ALWAR 400kV 84

CHITTORGARH 400kV

88

HINDAUN 400kV 91

BHAINSRA 92

CHHABRA 95

PARICHHA 400kV

UPPTCL

31

VISNUPRAYAG 64

ROSA 88

ALAKHNANDA 89

GONDA 400kV 92

PANKI 400kV 93

BANDA 400kV 93

ORAI 400kV 93

ALIGARH 94

MAINPURI 765kV 95

MURADNAGAR 400kV NEW

95

MURADNAGAR 400kV

95


All constituents were requested to look into the intermittency issue and

arrange for permanent solution in a time bound manner. Members agreed to

resolve the issues at the earliest.

19. Update of documents in line with Indian Electricity Grid Code (IEGC):

NRLDC is updating the document “Operating procedure of Northern region” and

“Power Maps of Northern region and related information”.

As per Indian Electricity Grid Code (IEGC), in respect of demand control, all efforts

must be made to avoid situation of low frequency. Hon’ble CERC in its order in

petition no 125/MP/2012 also directed to have the list of radial feeders which can be

opened on the directions of NRLDC to regulate the demand. List of such radial

feeders has been provided by respective utilities and is part of ‘Operating

Procedure of Northern Region’. Latest updated document is available at

https://nrldc.in/download/operating-procedure-of-northern-region-for-2017-18-

2/?wpdmdl=8251

As highlighted in previous meetings, in view of continuous network change and high

demand period during summer, it is desirable to have updated list of feeders. Thus,

each state control area is requested to update the information of feeders that can

be used for demand regulation by NRLDC (in addition to action by SLDC).

Following are the attributes for such feeders:

• Feeders shall be radial in nature

• They should usually have substantial load flow so that reduction of drawal

can be prominently noticed on opening of such lines.

Feedback in this regard has been received from Rajasthan SLDC. It is requested

that the respective information may be provided by others latest till 30th June 2021.

Further, any feedback regarding Operating Procedure document of Northern region

may also be shared latest till 30th June for incorporating the same in the updated

version of the document.

“Important Grid element of NR” document was updated in May 2021, and mailed to

all utilities. Document is also available at NRLDC website at this link

https://nrldc.in/download/nr-important-grid-elements-may-2021/?wpdmdl=9167.

It was requested to go through the document and provide the updated information

and feedback to modify the above document.

20. Computation of TTC/ATC of respective control areas

In last several OCC meetings, NRLDC had shared studies done for assessing the

TTC/ATC of different state control area for upcoming summer months as per

information available at NRLDC. Before summer season, each state shall assess and

share its ATC/TTC as agreed earlier and as per CERC regulations. Involvement of

SLDC officials in power system studies helps to assess TTC/ATC limits of the control

area and also provides information about likely constraints and precautionary actions

that may be taken to avoid high line/ICT loadings etc. This Intra-state TTC/ ATC

computations would also help to identify margins in transfer of power among NR-

https://nrldc.in/download/operating-procedure-of-northern-region-for-2017-18-2/?wpdmdl=8251

https://nrldc.in/download/operating-procedure-of-northern-region-for-2017-18-2/?wpdmdl=8251


Constituents. It is once again requested to SLDCs to go through these assessments

and provide comments. Reliability issues expected for next few months are highlighted

below:

State

Tentative ATC/ TTC during Summer-21

(MW)

Constraints anticipated

Actions required

Deliberations in 184 OCC meeting

Punjab

State own

generation=

5600 MW (High

hydro)

TTC= 7900 MW

(on managing

the load locally

at Rajpura ICTs)

ATC= 7300 MW

(Considering

reliability margin

as 600 MW)

N-1 compliance

issues at Rajpura,

Nakodar, and

Ludhiana ICTs

Many 220kV lines

near Amritsar(PG)

and Ludhiana(PG)

are also critically

loaded

Loading close to N-1

limits observed at

400/220kV Rajpura,

Naodar, Moga and

Ludhian ICTs at time

of import close to

ATC limit.

• Increase in

generation at 220kV

level would help in

meeting high demand

& also improve

voltage profile.

• Due to forced outage

of unit-3 of

TalwandiSaboo plant,

ATC/TTC of Punjab

state control area was

revised to

7300/7900MWtill July

2021 recently.

• Punjab SLDC

was asked to

ensure loading at

400/220kV ICTs

within their N-1

contingency limit.

It was also

discussed that

generation at

220kV may also

be optimally

scheduled so that

line, ICT loadings

and system

voltages remain

within limit.

UP

State

Gen TTC

AT

C

110

00

1380

0

132

00

115

00

1350

0

129

00

120

00

1330

0

127

00

N-1 compliance

issue at

Sohawal(PG),

Nehtaur, Mau, ICTs.

Many 220 kV lines

like Rosa-

Shahjahapur,

Hardoi-SarojiNagar,

Tanda-Basti and

Gorakhpur(PG)-

Gorakhpur etc. are

critically loaded

and need

monitoring.

Considering the

management of the

constraints at intra-

state level as

mentioned (local load

management and SPS

at highly loaded ICTs

and local load

management for highly

loaded 220 kV

network), the TTC/ATC

figures calculated and

furnished by UP SLDC

seem to be alright.

UP was asked to

explore requirement of

SPS scheme at heavily

constrained 400/220kV

ICTs.

Loading above N-

1 limit observed

at Sohawal in

May-June 2021 in

real-time.

UP SLDC was

asked to submit

220kV line

loadings at the

time of maximum

demand

observed in June

2021. Snapshot

and basecase for

instant of

maximum

demand to be

shared with

NRLDC.


Delhi

State own

generation =

600MW

TTC= 6800 MW

ATC= 6500 MW

(Considering RM

as 300 MW)

• N-1 non-

compliance issue

at, Bamnauli and

Mundka ICTS

• Due to radial

feeding of load

from most of the

stations, reliability

reduced.

• Loading above N-1

contingency limits

observed for some

duration at Bamnauli.

• Loading on highly

loaded 220 kV lines to

be monitored closely

and new

arrangements to feed

the load to be worked

on

• Delhi SLDC was

asked to share

latest ATC/TTC

assessment with

NRLDC/ NRPC

as the same is

already being

requested for last

several OCC

meetings.

Haryana TTC: 7900 ATC: 7300

• N-1 non-

compliance at

Deepalpur, Panipat

(BBMB) and

Abdullapur ICTs

• Loading close to

N-1 limit observed

at Deepalpur in

Apr-May 2021 in

real-time.

• 220kV Hisar(PG)-

Hisar(IA), Mohana-

Sonipat, Badshahpur-

Sohna Road etc. are

heavily loaded and

need to be strictly

monitored.

• Haryana SLDC

asked to explore

possibility of SPS

at 400/220kV

Deepalpur ICTs.

• Haryana SLDC

was asked to

share ATC for

June-Sep 2021.

• Haryana SLDC

asked to ensure

that loading of

ICTs are

maintained below

N-1 contingency

limits

As discussed in last OCC meeting, all SLDCs need to furnish ATC/TTC details of their control area at respective SLDC websites. However, it is being observed that only SLDCs of Haryana, UP, Punjab, Delhi (real-time violation) are uploading ATC/TTC limits on their websites. To assist SLDCs in ATC/TTC assessment, NRLDC has also been carrying out interactions over video-conference with SLDCs. All SLDCs are requested to share basecase as well as ATC/TTC assessment with NRLDC/NRPC on monthly basis as well as upload ATC/TTC limits on their websites.

SLDC Link for ATC on website

UP https://www.upsldc.org/documents/20182/0/ttc_atc_24-11-16/4c79978e-35f2-4aef-8c0f-7f30d878dbde

Punjab https://www.punjabsldc.org/downloads/ATC-TTC0321.pdf

Haryana https://hvpn.org.in/#/atcttc

Delhi NA (real-time violation reporting available)

Rajasthan NA

HP NA

Uttarakhand NA

J&K and Ladakh NA


J&K and Ladakh U/Ts, Uttarakhand and HP representatives were once again asked to advise the concerned officers to evaluate their ATC/TTC limits in coordination with NRLDC and share latest assessment with NRLDC and NRPC.

21. Compliance to LVRT and HVRT by RE Generators Regulation

In the meeting, it was deliberated that CEA (Technical standards for connectivity to

the Grid) Regulations-2007 under section B of Part-II of its notification dated

15.10.2013 stipulates that the installation of LVRT in Generating station connected

at 66kV and above. Further CEA (Technical standards for connectivity to the Grid)

Regulations-2007 under section B of Part-II of its notification dated 06.02.2019

stipulates the installation of LVRT & HVRT in Generating stations. The

amendments are applicable to all new generating units commissioned after 6th Aug

2019.

S. No.

Applicable to Connected

at LVRT HVRT Remarks

1

Solar/ Wind Plants

commissioned after

06.08.2019

at all voltage

level Applicable. Applicable.

As per CEA connectivity regulation

2019

2

Wind Plants commissioned

from 15.04.2014- 06.08.2019

at 66kV and above

Applicable. Not

Applicable

LVRT characteristics as per CEA Connectivity

Regulations 2013 compulsorily

3


from 15.04.2014- 06.08.2019

at below 66kV

Not Applicable

Not Applicable

Not mandatory. However, generator

and licensee of electrical system may mutually discuss and agree on measures if technically feasible

4


before 15.04.2014

at all voltage

level

Not Applicable

Not Applicable

This issue especially considering Rajasthan SLDC was also discussed in 45th TCC

and 48th NRPC meeting held in Aug/Sep 2020 and following was agreed:

• Wind generators with LVRT compliance certificate needs to be checked

periodically through online data and if it is false declaration then a petition

may be filed against the generators by SLDC/ RRVPNL.

• POWERGRID shall resolve the REMC issue (single forecast and REMC

utilization) of Rajasthan SLDC as soon as possible.

• Cascade tripping needs to be avoided through transmission strengthening in

intra state network by RRVPNL.

• SLDC Rajasthan shall provide the quarterly compliance report of wind

generators to NRLDC/ NRPC.


• SLDC Rajasthan shall approach the MoP, MNRE for funding related issues

and also expedite the way to make 2.8 GW of existing wind generators LVRT

compliant in its control area. It would be helpful for safe and secure operation

of the grid.

Rajasthan SLDC was requested to share actions taken by them for compliance of

decisions of 45th TCC and 48th NRPC meeting. Rajasthan SLDC representative

informed that proposal for PSDF funding for ensuring LVRT compliance in old

plants is under process as per orders from higher management. In this regard, cost

estimates are being taken from old wind generators. However, estimates are being

received only from some of the wind generators.

It was suggested that a separate meeting may be called with all wind developers in

Rajasthan and participants from NRPC, NRLDC, Rajasthan SLDC so that all issues

related to wind generators including LVRT non-compliance etc. may be discussed

and resolved. Rajasthan SLDC agreed for the same.

It was also stressed that certificate may be obtained from wind generator that

turbine is LVRT compliant as per regulatory requirements. Moreover, it becomes

important that during fault events, LVRT compliance is checked at SLDC level.

It is known that significant solar generation has been/ is being commissioned in

Punjab and UP state control area. Therefore, the updated status of compliance

details of LVRT and HVRT requirement was requested to be submitted by

respective SLDCs.

22. Frequent forced outages of transmission elements in the month of May’21:

The following transmission elements were frequently under forced outages during

the month of May’’21:

Sl. No.

Element Name No. of forced

outages Utility/SLDC

1 400 KV Alwar(ATIL)-Hindaun(RS) (ATIL) Ckt-1

4 Rajasthan

2 400 KV Agra-Unnao (UP) Ckt-1 3 UP

3 400 KV Anpara-Sarnath (UP) Ckt-1 3 UP

4 400 KV Banda-Rewa Road (UP) Ckt-1 3 UP

5 400 KV Kankani-Jaisalmer (RS) Ckt-2 3 Rajasthan

6 400 KV Muktsar-Makhu (PS) Ckt-1 3 Punjab

7 400 KV Muradnagar_2-Mathura (UP)

Ckt-1 3 UP

8 220 KV Dhauliganga(NH)-

Pithoragarh(PG) (PG) Ckt-1 4 NHPC/POWERGRID


9 220 KV Ranpur(RS)-Bhanpura(MP)

(RS) Ckt-1 3 Rajasthan

The complete details are attached at Annexure-B. II of the Agenda.

Discussion during the meeting:

• 400 KV Agra-Unnao (UP) Ckt-1: UPPTCL representative informed that

frequent fault is occurring in this line due to design issue and low clearance

in some section of the line leading to a number of A/R (auto reclosure)

operation. Due to repeatedA/R (auto reclosure) operation, breaker contacts

may become loose and A/R (auto reclosure) fail to operate in some case. He

further informed that in an internal meeting, it was suggested to Agra and

Unnao station to check the breaker contacts and ensure healthiness/ in

service of A/R in this transmission line in compliance to CEA Grid Standard.

• 400 KV Anpara-Sarnath (UP) Ckt-1: UPPTCL representative informed that

whenever there was a fault in this line, line tripping was happening due to DT

received at Sarnath end and A/R (auto reclosure) was not operating in this

line. To avoid the issue, PLCC channel and auto reclosure was kept off at

Anpara end. He further informed that in an internal meeting, it was


suggested to Anpara to ensure healthiness/ in service of A/R in this

transmission line in compliance to CEA Grid Standard.

NRLDC representative emphasized that this is an important line connected to

Anpara Generating station and any issue on this line needs to be addressed

immediately. He further suggested to expedite and complete the work to

resolve the issue as early as possible. UPPTCL representative agreed for the

same.

• 400 KV Banda-Rewa Road (UP) Ckt-1: UPPTCL representative informed

that three tripping occurred in this line due to overvoltage observed at 400kV

Banda end and DT received at 400kV Rewa Road end. He further informed

that 125Mvar Bus reactor at Banda was not available during tripping and

restored on 31st May 2021. Since then, no tripping on overvoltage has been

observed in this line.

• 400 KV Muradnagar_2-Mathura (UP) Ckt-1: UPPTCL representative

informed that frequent fault in this line occurring due to design issue and low

clearance of phase to earth in angular section of the line leading to a number

of A/R (auto reclosure) operation. Also, presence of birds near Dasna area

leads to many faults in the line. Due to repeated A/R (auto reclosure)

operation, auxiliary breaker contacts at Mathura end become disturbed and

A/R (auto reclosure) fail to operate in some case. He further informed that in

an internal meeting, it was suggested to Mathura station to maintain the

breaker contacts and ensure healthiness in service of A/R in this

transmission line in compliance to CEA Grid Standard.

NRLDC representative suggested to expedite and complete the work to

resolve the issue as early as possible. UPPTCL representative agreed for

the same.

• 400 KV Kankani-Jaisalmer (RS) Ckt-2: Rajasthan representative informed

that NGR relay of Line reactor was faulty at Jaisalmer end due to which A/R

(auto reclosure) was kept in off condition and line was tripping in transient

fault. He further informed that problem has been resolved now and line was

in supervision and A/R (auto reclosure) is expected to be enabled by next

week.

• 220 KV Ranpur (RS)-Bhanpura (MP) (RS) Ckt-1: Rajasthan representative

informed that

o On 09th&10thMay 2021, tripping in line occurred due to heavy rains

and bad weather. Line auto reclosed and again tripped due to fault

reoccurred in breaker reclaim time of 25 second.

o On 19th May 2021, line tripped due to Overvoltage Stage1 protection

operated at Ranpur end.


NRLDC representative informed that as per NRPC protection philosophy,

overvoltage protection should not be enabled at 220kV lines. He further

suggested to keep the protection settings in line with the NRPC approved

philosophy to avoid unwanted tripping of the line.

• 400 KV Alwar (ATIL)-Hindaun (RS) (ATIL) Ckt-1: Rajasthan representative

informed that frequent fault in this line occurring due to low clearance issue

in some section of the line after OPGW work.

• 400 KV Muktsar-Makhu (PS) Ckt-1: Punjab representative informed that

frequent fault in this line occurring and fault was observed by patrolling team

on 09th & 10th May 2021. However, no fault has been observed on 31st May

2021. NRLDC representative emphasised that this is a peak demand period

in Punjab and line availability has to be ensured. He further suggested to

thoroughly patrol the line and resolve the issue to avoid frequent tripping in

future.

• 220 KV Dhauliganga (NH)-Pithoragarh (PG) (PG) Ckt-1: POWERGRID

representative informed that, DT was observed at Pithoragarh (PG) end in

three tripping out of total four tripping. NRLDC representative informed that

line may be tripping due to operation of DEF relay due to current in neutral

and the same needs to be confirmed. He further emphasised that this is an

important line evacuating generation of Dhauliganga HEP and frequent

tripping of this line leads to generation loss and poses a serious threat for the

grid security. He suggested that one to one testing of PLCC may be carried

out by NHPC and POWERGRID. He asked to collect all the information

regarding tripping of this line and share the detail report within 7 days.

POWERGRID representative agreed for the same.

NRLDC representative emphasized that A/R (auto reclosure) issue was found in

many of these tripping. He further sensitized all the utilities to ensure healthiness/ in

service of A/R in 220 kV and above transmission lines in compliance to CEA Grid

Standard. He further informed that most of the tripping are transient in nature but

due to non-operation of A/R, it resulted into tripping of the transmission element and

it further reduce the reliability of the grid. All the utilities shall endeavour to keep

auto reclosure in service and in healthy condition for 220 kV and above voltage

level transmission line.

Frequent outages of such elements affect the reliability and security of the

grid. Hence, utilities are once again requested to look into such frequent

outages and share the remedial measures taken/being taken in this respect.

23. Multiple element tripping events in Northern region in the month of May’21

A total of 26 grid events occurred in the month of May’21 of which13 are of GD-1

category. The preliminary report of all the events have been issued from NRLDC. A

list of all these events along with the status of details received by 05-June-2021 is

attached at Annexure-B.III of the Agenda.

Monthly compiled information is presented in graphical form as below:


Further, despite persistent discussions/follow-up in various OCC/PCC meetings, the

compliance of the regulations is still much below the desired level.

Maximum Fault Duration is 2280ms in the event of multiple element tripping at 220

kV Ziankote (JK) on 27-May-21 at 14:38hrs.

Delayed clearance of fault (more than 100ms for 400kV and 160ms for 220kV

system) observed in total 8 events out of 26 grid events occurred in the month. In

2number of events, fault didn’t capture through PMU data.

NRLDC representative stated that in the event of tripping at 220 kV Ziankote (JK)

on 27-May-21 at 14:38hrs, all four lines from 220kV Ziankote tripped with a delayed

clearance of 2280ms. POWERGRID representative informed that they will collect

the relevant information about this tripping and submit the detailed report. J&K

representative was not present in the meeting.

NRLDC representative raised concern about poor status of report updation on

the tripping portal. POWERGRID, UP &Punjab representative informed that

due to outbreak of Covid-19, they were not able to upload the tripping reports

in some events. NRLDC representative stated that timely report submission is

an important activity and all constituents are advised to take this on priority

and upload the reports.


OCC suggested all the NR constituents to update the information on tripping portal

developed by NRLDC. All the constituents agreed to take proactive actions in this

regard to minimize the tripping.

Members were asked to take expeditious actions to avoid such tripping in

future and discuss the same. Moreover, utilities may impress upon all

concerned for providing the Preliminary Report, DR/EL & Detailed Report of

the events in line with the regulations. Members agreed to take action in this

regard.

24. Details of tripping of Inter-Regional lines from Northern Region for May’21:

A total of 15 inter-regional lines tripping occurred in the month of May’21. The list is

attached at Annexure-B. IV of the Agenda.

Out of 15 number of tripping’s, 3 tripping incidents is related to HVDC system. The

status of receipt of preliminary reports, DR/EL within 24hrs of the event and fault

clearing time as per PMU data has also been mentioned in the table. The non-

receipt of DR/EL & preliminary report within 24hrs of the event is in violation of

various regulations. As per regulations, all the utilities shall furnish the DR/EL, flag

details & preliminary report to RLDC/RPC within 24hrs of the event. They shall also

furnish the detailed investigation report within 7 days of the event if fault clearance

time is higher than mandated by CEA (Grid Standard) Regulations.

NRLDC representative raised concern about delayed updation of report on the

tripping portal. POWERGRID representative informed that due to outbreak of

Covid-19, they were not able to upload the tripping reports within the stipulated time

of 24hrs.

Members may please note and advise the concerned for taking corrective

action to avoid such tripping as well as timely submission of the information.


25. Status of DR/EL and tripping report of utilities for the month of May’21.

NRLDC representative informed the current status (as on 05th June 2021) of DR/EL

and tripping report of utilities for the month of May 2021. Consolidated information

is tabulated below:

It is to be noted that as per the IEGC provision under clause 5.2 (r), detailed tripping

report along with DR & EL has to be furnished within 24 hrs of the occurrence of the

event. However, it is evident from the submitted data that reporting status is not

satisfactory and needs improvement. Also, it is observed that reporting status has

been improved fromCPCC1, CPCC2, Delhi, HP and Haryana in May, 2021

compared to the previous month.

NRLDC representative stated that despite of discussion in various OCC meeting

status is still poor for PG-NR3, UP, Uttarakhand, Rajasthan, Punjab and J&K.

PG-NR 3 representative agreed to further improve the status in upcoming months.


Punjab representative informed that due to outbreak of Covid-19, they were not

able to upload the tripping reports in some events and reporting will further improve

in upcoming months.

NRLDC representative raise concern about poor status of report updation of

Uttarakhand control area. Uttarakhand representative was not present in the

meeting for comment.

UP representative informed that they are regularly conducting meetings and

sensitizing stations to upload the report. He further informed that status has been

improved from their control area and reporting will further improve in upcoming

months.

All the members were once again requested to provide timely details of the

grid events, detailed report in desired format along with remedial measure

report. DR/EL of all the tripping needs to be uploaded on Web Based Tripping

Monitoring System “http://103.7.128.184/Account/Login.aspx” within 24 hours

of the events as per IEGC clause 5.2.r and clause 15.3 of CEA grid standard.

Members agreed for the same.

26. Status of PSS tuning/ re-tuning and Step Response Test of generator

Power System Stabilizer is an important part for damping of inter area and local

mode of oscillations in the grid. As we all know, Indian electricity grid is

continuously expanding and lots of Power Electronics devices were also

commissioned in recent years changing the dynamics of grid. PSS tuning /re-tuning

is required for damping of oscillations.

In this regard one committee at NRPC level was formed in year 2014 and it was

agreed that If results of Step Response Test indicate sufficient damping, generating

company would perform next Step Test after three year or at the time of major

overhauling of the machine, whichever will be earlier and Generating Companies

would arrange for re-tuning of PSS, if Step Response Test indicates insufficient

damping or oscillations.

In 180th, 181st,182nd& 183rdOCC meeting, this point was discussed and Utilities

were requested to submit the present status of PSS tuning/re-tuning and Step

Response Test as per the below mentioned format.

S.

No.

Name of the

Generating

Station

Date of last PSS

tuning / re-tuning

performed (in

DD/MM/YYYY

format )

Date of last Step

Response Test

performed (in

DD/MM/YYYY

format )

Report

submitted

to NRLDC

(Yes/ No)

Remarks

(if any)


Status report in above format updated till 08thJune 2021is attached as Annexure-

B.VI of the Agenda.

It is once again requested to all the members to submit the report of PSS tuning/ re-

tuning/ Step Response Test through email to NRPC and NRLDC at seo-

[email protected] and [email protected] respectively.

OCC members agreed to share the existing status with NRPC/ NRLDC within

15days.

27. Frequent Multiple elements tripping occurring at 220kV Ziankote (JK):

Frequent events of multiple elements tripping have been observed in J&K(UT)

control area. Following three events have occurred in J&K(UT) control area which

had the potential for cascade tripping and further aggravating the contingent

situation:

• At 20:11 Hrs on 22nd May 2021, multiple elements tripping occurred at

220kV Ziankote (JK). As per the details received, R-N phase to earth fault is

observed at a distance of 28.6km from Wagoora (PG) end. PMU voltage plot

indicates that fault cleared in 400ms. As per NRLDC SCADA, load loss of

approximately 550MW is observed.

• At 14:38 Hrs on 27th May 2021, multiple elements tripping occurred at

220kV Ziankote (JK). As per the details received, B-N phase to earth fault is

observed at a distance of 28.6km from Wagoora (PG) end. PMU voltage plot

indicates that fault cleared in 2200ms. As per NRLDC SCADA, load loss of

approximately 510MW is observed.

• At 13:15Hrs on 8th June, 2021, multiple elements tripping occurred at 220kV

Ziankote (JK). As per the details received, Y-B phase to phase fault is

observed at a distance of 50.89km from Wagoora (PG) end. PMU voltage

plot indicates that fault cleared in 800ms. As per NRLDC SCADA, load loss

of approximately 550MW is observed.

NRLDC representative stated that three multiple element tripping occurred at 220

kV Ziankote (JK) during last month and in all the events tripping with delayed

clearance is observed. POWERGRID representative informed that they will collect

the relevant information about all the events and submit the detailed report. J&K

representative was not present in the meeting for any comment.

NRLDC representative emphasized that such delayed clearance of fault and

tripping of multiple elements is a matter of serious concern for reliability and

security of the gird. Hence, utilities are requested that the above-mentioned grid

events in J&K(UT) control area may be analysed in detail and shortcoming in the

operation and protection system may be immediately resolved.


28. Frequent tripping of 400 KV Wangto_GIS(HP)-Sorang(Greenko) (Greenko)

Ckt-1 &400 KV Kala Amb(PKTL)-Sorang(Greenko) (Greenko) Ckt-1:





Frequent tripping of recently commissioned section of 400 KV Wangto_GIS(HP)-

Sorang (Greenko) (Greenko) Ckt-1& 400 KV Kala Amb (PKTL)-Sorang (Greenko)

(Greenko) Ckt-1 has been observed in the system.

• At 03:01Hrs on 12th June 2021, 400 KV Kala Amb (PKTL)-Wangto_GIS(HP)

(HPPTCL) Ckt-1 tripped on B-N fault at a Distance of 101km from Kala Amb.

• At 03:01Hrs on 12th June 2021, 400 KV Wangto_GIS(HP)-Sorang (Greenko)

(Greenko) Ckt-1 tripped on phase-to-phase fault.

• At 03:12Hrs on 12th June 2021, 400 KV Kala Amb (PKTL)-Sorang (Greenko)

(Greenko) Ckt-1 tripped on R-N fault at a Distance of 97km from Kala Amb.

NRLDC representative stated that tripping of these elements during high Hydro

season is a matter of serious concern for reliability and security of the gird. Hence,

utilities are requested that the above-mentioned grid event may be analysed in

detail and shortcoming in the operation and protection system may be immediately

resolved. Greenko representative was not present in the meeting for any comment.


***

- - 1 ~20.14 85.84

Annexure-A.I (A)

- - 1

~23.64% ( ~64.81 )

Annexure-A.I (B)

- 1 1.25

Annexure-A.I (C)

- -1

13.70% (9.29 )

Annexure-A.I (D).

S. No. Type of transmission element Total No

1 220kV line 01

2 LILO of lines 05

3 500 MVA ICT 01

4 150 MVA ICT 02

5 100 MVA ICT 03

6 765kV, 400kV, 220 kV Bays 21

Total New Elements charged 33

Annexure-A.I (E)

Transmission Lines (220kV Lines- 15.56 Ckt. Kms)

Sr. No. Name of element Voltage Level (in

kV)

Line Length (In kM)

Conductor Type

Agency/ Owner Location Remarks

Date & time of charging

Date Time

1

220kV Bhadla(PG)-Mahindra-S/C line along with associated bay no 201 at Mahindra & 227

at Bhadla(PG)

220 15.56 Single Zebra Mahindra Rajasthan 05.05.2021 19:39

LILO of Transmission Lines

Sr. No. Name of element

Voltage Level (in

kV)

Line Length (Before

LILO)

Line Length (Kms)

LILO Line Length (Kms)

Conductor Type

Agency/ Owner Location Remarks


Date Time

1

400kV Aligarh-Harduaganj line along

with associated main bay 407 at Harduaganj

400 40 Twin Moose UPPTCL UP 22.05.2021 19:06

2

400kV Sikandrabad-Harduaganj line along

with associated main bay 404 at Harduaganj

400 115.4 Twin Moose UPPTCL UP 22.05.2021 20:40

3

400kV Sorang-Kala Amb(PG)-line 2 along

with associated bay no D01 at Sorang (LILO of

400kV Wangtu-Kala Amb at Sorang)

400 175.7 160.6 3.123 Quad Moose Sorang HP 01.06.2021 16:35

4

220kV Samba(PG)-Bishnah line { LILO of

220kV Hiranagar-Bishnah at Samba(PG)}

220 45 32.4 2 Single Zebra JKPTCL J&K 11.05.2021 17:26

5

220kV Samba(PG)-Hiranagar line-2 { LILO of 220kV Hiranagar-Bishnah

at Samba(PG)}

220 45 16.5 2 Single Zebra JKPTCL J&K 30.05.2021 08:39

ICT (MVA Capacity Addition- 1100 MW)

S.No. Name of element Voltage Level

Transformation Capacity (in

MVA)

New/replacement

/augmentation Make Configurat

ion Agency/ Owner Remarks

Actual date & time of charging

Date Time

1

100 MVA Power Transformer along with associated bay no 202 at Mahindra

220/33 100 New Prime Meidan 3-Ph. Mahindra 07.05.2021 16:34

2



3



4 500 MVA ICT-1 along with associated existing Dia No 4 at Akal

400/220/33 500 New T&R 3-Ph. RRVPNL

Replacement of 315 MVA ICT

for augmentation of ICT capacity

10.05.2021 16:07

5 400/33kV, 150 Power Transfomer-1 at Azure PSS 400/33 150 New Siemens 3-Ph. Azure Charged on no-

load 08.05.2021 22:16

6 400/33kV, 150 Power Transfomer-2 at Azure PSS 400/33 150 New Siemens 3-Ph. Azure Charged on no-

load 09.05.2021 18:27

Bus and Bays

Sr. No. Name of element Type Voltage Level (in kV)

Agency/ Owner Remarks


Date Time

1 220kV Bus Sectionalzer 215 of Bus A-B at Bus-1 Bhadla(PG) Bay 220 PGCIL 02.05.2021 08:14

2 220kV Bus Sectionalzer 216 of Bus B-C at Bus-2 Bhadla(PG) Bay 220 PGCIL 02.05.2021 08:12

3 220kV Bay No 227 for Mahindra line at Bhadla(PG) Bay 220 Mahindra 03.05.2021 06:26

4 220kV Bay No 201 for Bhadla(PG) line at Mahindra Bay 220 PGCIL 05.05.2021 19:21

5 220kV Bus Coupler Bay No 204 at Mahindra Bay 220 Mahindra 05.05.2021 19:39

6 220kV Bus-1 at Mahindra Bay 220 Mahindra 05.05.2021 19:39

7 220kV Bus 2 at Mahindra Bay 220 Mahindra 05.05.2021 19:39

8 220 kV Bay 213 of Samba JKPTCL line-1 at Samba PG. Bay 220 PGCIL 17.05.2021 13:49

9 220 kV Bay 211 of Samba JKPTCL line-2 at Samba PG. Bay 220 PGCIL 17.05.2021 14:02

10 400kV Main Bay D01 of Kala Amb Line-1 at Sorang Bay 400 PGCIL 31.05.2021 15:40

11 400kV Main Bus-1 at Sorang Bay 400 Sorang 31.05.2021 15:40

Bus and Bays

Sr. No. Name of element Type Voltage Level (in kV)

Agency/ Owner Remarks


Date Time

12 400kV Main Bus-2 at Sorang Bay 400 Sorang 31.05.2021 15:58

13 400kV Bus Coupler D03 at Sorang Bus Coupler 400 Sorang 31.05.2021 15:58

14 220kV Bay no 208 for Hiranagar line at Samba Bay 220 PGCIL 11.05.2021 17:43

15 220kV Bay no 209 for Bishnah line at Samba Bay 220 PGCIL 11.05.2021 17:26

16 765kV Bay No 704 of Ghatampur line at Hapur Bay 220 UPPTCL 05.05.2021 18:47

17 400kV Tie Bay No 402 of Bikaner(PG) line & Power Transformer-1 at Bikaner PSS Azure

Bay 400 Azure 08.05.2021 22:16

18 400kV Main Bay No 403 of Power Transformer-1 at Bikaner PSS Azure Bay 400 Azure 09.05.2021 01:03

19 400kV Tie Bay No 405 of Bikaner(RSS Azure) line & Power Transformer-2 at Bikaner PSS Azure

Bay 400 Azure 09.05.2021 18:27

20 400kV Main Bay No 406 of Power Transformer-1 at Bikaner PSS Azure Bay 400 Azure 09.05.2021 18:51

21 400kV Main Bus-2 at Bikaner PSS Azure Bay 400 Azure 09.05.2021 01:03

S.No. Capacity to be charged out of 250 MW

Voltage Level

Installed Capacity (in MW)

Make (Inverter & IDT) Inverter Capacity

& No

IDT Capacity

& No IDT No Feeder & ICR

No Agency/ Owner

Evacuation Path


Date Time

1 100 33 250

Sungrow & Toshibha 3.125*4 12.5 MVA 16 105 & ICR-16

Mahindra

220kV Bhadla(PG)-Mahindra-

S/C.

Power flow started

from 08.05.2021

07.05.2021 16:39

Sungrow & Toshibha 3.125*4 12.5 MVA 17 110 & ICR-17 07.05.2021 15:12







Power Transformaer-1 (33kV Side) 100 1 123 07.05.2021 01:07




2 33kV Bus Coupler-1 117 07.05.2021 01:15

3 33kV Bus Coupler-2 107 07.05.2021 01:25

4 Auxillary Transformer 108 07.05.2021 02:19

5 Auxillary Transformer 101 07.05.2021 02:22

MAHINDRA SOLAR

S.No. Voltage Level


Fuel Type Plot No Make (Inverter & IDT)

Inverter Capacity &

No

IDT Capacity

& No

Feeder Capacity &

No Agency/ Owner Evacuation

Path


Date Time

1 33 300 Solar

33kV Bus 1A Azure 43

400kV Bikaner(PG)-Bikaner PSS

10.05.2021 18:50

33kV Bus 1B Azure 43 10.05.2021 21:26

33kV ICT-1 CVB Board Panel 11 Azure 43 10.05.2021 18:50




AZURE 43 PSS SOLAR

S.No.

Capacity to be charged out of 250

MW

Voltage Level


Fuel Make

(Inverter & IDT)

Inverter Capacity

& No

IDT Capacity

& No IDT No Feeder &

ICR No Agency/ Owner

Evacuation Path


Date Time

6

62.5 33 250 Solar

Sungrow & Toshibha 3.125*4 12.5 MVA 8 115 & ICR-8

Mahindra

220kV Bhadla(PG)-Mahindra-

S/C.

Power flow started from 04.06.2021

03.05.2021 17:38

7 Sungrow & Toshibha 3.125*4 12.5 MVA 9 116 & ICR-9 03.05.2021 18:41




MAHINDRA SOLAR

H` GENERATING UNITS

S.No Station Owner Outage Reason Outage Date Outage Time

Outage duration(in

days)

1 126 MW Bhakra HPS - Unit 3 BBMB Renovation and Maintenance

work. Expected by July-2021 01-04-2019 09:20 804

2 126 MW Bhakra HPS - Unit 7 BBMB Renovation and Maintenance

work. Expected by June-2021 01-04-2019 09:20 804

3 500 MW Anpara-D TPS - unit 2 UPPTCL Generator blast due to

hydrogen leakage. 13-11-2019 14:14 577

4 40 MW Sewa-II HPS - UNIT 2 NHPC

Excessive leakage in HRT between audit-II and Dam.

Expected by December 25-09-2020 00:00 261







7 600 MW RGTPP (Khedar) - UNIT 2 HVPNL Capital Overhauling 02-03-2021 00:00 103

8 60 MW Bairasiul HPS - UNIT 3 NHPC

Renovation and modernization of unit.

Expected by September 2021 27-11-2020 10:00 198

Annexure-A.I (F).

S.No Station Owner Reason(s) Outage Date & Time

Outage duration(in days)

9 165 MW Dehar HPS - UNIT 3 BBMB Penstock inspection. Expected by

July 2021. 28-10-2020 11:50 228

10 165 MW Dehar HPS - UNIT 4 BBMB Penstock Inspection. Expected by

June 2021. 28-10-2020 11:50 228

11 200 MW Singrauli STPS - UNIT 3 NTPC

Turbine Problem TG BRG VIBRATION HIGH. Expected by

June 2021. 16-03-2021 11:43 89

12 660 MW Talwandi Sabo TPS - UNIT 3 PSPCL Due to abnormal sound in boiler.

Expected by July-2021 27-02-2021 19:34 105

13 66 MW Pong HPS - UNIT 5 BBMB To attend damaged break pad for

turbine. Expected by June 2021 08-03-2021 09:00 97

14 500 MW Rihand-II STPS - UNIT 2 NTPC Over hauling work. Expected by

June-2021 30-03-2021 23:10 74

15 250 MW Chhabra TPS - UNIT 2 RRVPNL Over hauling Annual Maintenance 01-04-2021 00:00 73

16 660 MW Chhabra SCTPS - UNIT 5 RRVPNL ANNUAL SHUT DOWN 01-04-2021 00:05 73

17 250 MW Chhabra TPS - UNIT 1 RRVPNL M/T Due to scarcity of water 16-04-2021 00:00 58

S. No` Element Name Type Owner Outage Date and Time Outage days Reason / Remarks

A LINE

1 220 KV Kishenpur(PG)-Ramban(PDD) (PDD) Ckt-1 Line PDD JK 31-03-2020 16:43 438

Due to heavy land slide near village Dalwas at Ramban damages occurred to 220 KV D/C KPTL at Location No :-187,188 &189 and there is every apprehension of collapsing Tower Loc No 189 .

2 400 KV Bareilly-Unnao (UP) Ckt-1 Line UPPTCL 12-05-2021 18:52 31

R-B fault, Zone-1, Dist. 152.4km, Fault current Ir 3.28kA, Iy 3.48kA from Unnao. On patrolling, tower no. 456 and 457 were found damaged/collapsed.

3 400 KV Bareilly-Unnao (UP) Ckt-2 Line UPPTCL 12-05-2021 18:52 31

R-B fault, Dist. 94.7km, Fault current Ir 5.05 kA & Ib 5.1 kA from Bareilly. On patrolling, tower no. 456 and 457 were found damaged/collapsed.

B BUS & BAYS

1 202 MAIN BAY - 220KV BUS 1 AT SHAHJAHANPUR(PG) (POWERGRID) BAY POWERGRID 23-02-2021 10:19 83 For termination of 220 kV Ajijpur-Paina

Line(New UPPTCL line) with bay 202

2 203 MAIN BAY - 220KV BUS 1 AT SHAHJAHANPUR(PG) (POWERGRID) BAY POWERGRID 23-02-2021 10:19 83 For termination of 220 kV Ajijpur-Paina

Line(New UPPTCL line) with bay 203

3 400 KV Gumma (HP) - Bus 1 BUS HPPTCL 05-05-2021 04:13 39 BB Z-1 Check Zone fault tripped B403 (ICT-2) at 04:13 Hrs. Master Trip of B403 could not be reset.

4 X5 MAIN BAY - 400 KV BHIWANI(BB)-RAJPURA(PS) (BB) CKT-1 AT BHIWANI(BB)

BAY POWERGRID 09-04-2021 09:40 65 Major Annual Maintenance.

5 720 TIE BAY - 765 KV BHADLA-BIKANER (PG) CKT-1 AND FUTURE AT 765 KV BIKANER(PG)

BAY POWERGRID 10-04-2021 10:03 64 Bay Extension work of Bikaner Khetri Transmission Limited.

6 400 KV Kadarpur (GPTL) - Bus 1 BUS GPTL 17-04-2021 13:18 56 E/S/D taken due to abnormal humming sound observed from 400KV B-phase BUS-1 CVT at Kadarpur. Replacement of VT pending.

Annexure-A.I (G).

S.No Element Name Type Owner Outage Outage days Reason / Remarks

C ICT

1 400/220 kV 315 MVA ICT 1 at Bhilwara(rs)

ICT RRVPNL 12-05-2019 23:42 735 Oil leakage in transformer. Expected revival in Dec-2021.

2 400/220 kV 315 MVA ICT 1 at Muradnagar_1(UP)

ICT UPPTCL 13-03-2020 02:46 457

Buccholz relay alarm and Local Breaker Backup protection operated. Tripped along with Hapur-Muradnagar line. Flags are not reset because of cable flashover. To be replaced by 500 MVA ICT.

Expected revival in May-2021.

3 400/220 kV 315 MVA ICT 2 at Bawana(DV) ICT DTL 30-03-2021 17:35 74

400kV side B-phase bushing blasted. Tripped on differential protection, REF protection. ICT catches

fire and damaged.

4 400/220 kV 500 MVA ICT 2 at Noida Sec 148(UP)

ICT UPPTCL 19-08-2020 16:30 298 500 MVA ICT-I also got damaged due to fire in ICT-II, for protection testing. Expected revival in June-

2021.

5 400/220 kV 315 MVA ICT 2 at Orai(UP) ICT UPPTCL 22-03-2021 15:51 82 R-phase HV (400kV) & MV (220kV) Bushing of 315

MVA ICT-2 got damaged at 400 KV S/S ORAI.

6 400/220 kV 315 MVA ICT 1 at Lahal(HP) ICT HPPTCL 18-04-2021 19:42 55 To attend low oil level alarm in ICT.

7 220/33 kV 125 MVA ICT 1 at Saurya Urja Solar(SU) ICT Saurya Urja 27-05-2021 06:24 17 Operation of transformer protection

D BUS REACTORS

1 80 MVAR Bus Reactor No 1

at 400KV Nathpa Jhakri(SJ)

BR SJVNL 17-10-2019 12:58 577

Flashover/Fault in 80MVAR Bus Reactor cleared by Bus Bar Protection. Expected revival in Nov-2021.

1

◎ Sep-2019

◎ Apr-2021

◎ Feb-2021

◎ Mar-2021

◎ Not Available

◎ Mar-2021

◎ Apr-2021

◎ Apr-2021

◎ May-2021

◎ Not Available

◎ Mar-2021

◎ Mar-2021

◎ Mar-2021

◎ Not Available

◎ Mar-2021

◎ Dec-2020

◎ Mar-2021

◎ Mar-2021

◎ Dec-2020

◎ Feb-2021

◎ May-2021

◎ May-2021

◎ May-2021

◎ May-2021

2

3

4

Progress of installing new capacitors and repair of defective capacitors

Healthiness ofdefence mechanism:Self-certification

UP

UTTARAKHAND

BBMB

HARYANA

PUNJAB

RAJASTHAN

UP

NTPC

Report of mock exercise for healthiness of UFRs carried out by utilities themselves on quarterly basis is to be submitted to NRPC Secretariat and NRLDC. All utilities were advised to certify specifically, in the report that “All the UFRs are checked and found functional”.

Status of FGD installation vis-à-vis installation plan at identified TPS

List of FGDs to be installed in NR was finalized in the 36th TCC (special) meeting dt. 14.09.2017. All SLDCs were regularly requested since 144th OCC meeting to take up with the concerned generators where FGD was required to be installed.Further, progress of FGD installation work on monthlybasis is monitored in OCCmeetings.

All States/utilities are requested to furnish updated status of FGD installation progress on monthly basis.

All States/UTs are requested to furnish updated status on monthly basis.

Status of the information submission (month) from states / utilities is as under:

Data upto following months, received from various states / UTs:

CHANDIGARH

DELHI

HARYANA

All States/UTs are requested to furnish updated status on monthly basis.

HP

J&K and LADAKH

PUNJAB

RAJASTHAN

Follow up issues from previous OCC meetings

Sub-stations likely to be commissioned by next two years.

All the concerned states had been requested in past OCC meetings to submit the details of the downstream network associated specially with POWERGRID substations along with the action plan of their proposed / approved networks.

Status details of downstream networks mentioned in Annexure-A.II.I.

Data upto following months, received from various states / UTs:

CHANDIGARH

DELHI

HARYANA

HPInformation regarding installation of new capacitors and repair of defective capacitors is to be submitted to NRPC Secretariat.

J&K and LADAKH

PUNJAB

RAJASTHAN

UP

UTTARAKHAND

Annexure-A.II

i

ii

iii

iv

v

vi

vii

viii

ix

x

xi

1x125 MVAr at 400 kV & 1x25 MVAr at 220 kV

Retendering to be done for 400kV reactors. Price bid for 220kV reactors opened on 06.04.2021.

Nakodar 1x25 MVAr at 220 kV Technical bids opened on 14.01.2021.

1x25 MVAr

LOA placed on dt. 4.1.2021. Agreement signed on dt. 8.02.2021. Case for 2nd installment would be forwarded to NLDC, POSOCO. The target date is Nov’2021.

5

RAJASTHAN Akal

PUNJAB Dhuri

PUNJAB

DTL Harsh Vihar 2x50 MVAr at 220 kVPO awarded to M/s Kanohar Electricals Ltd.

DTL Mundka1x125 MVAr at 400 kV & 1x25 MVAr at 220 kV

Bay work awarded to M/s. Ethos. Reactor part tender is dropped and at present same is under revision.

PTCUL Kashipur 1x125 MVAR at 400 kVAlready submitted to PSDF. On hold due to policy decision

DTL Bamnauli 2x25 MVAr at 220 kVBay work awarded to M/s. Ethos. Reactor part tender is dropped and at present same is under revision.

DTL Indraprastha 2x25 MVAr at 220 kVBay work awarded to M/s. Ethos. Reactor part tender is dropped and at present same is under revision.

DTL Electric Lane 1x50 MVAr at 220 kV PR No 1100002374, Under Tendering

State / Utility

Substation Reactor Status

POWERGRID Kurukshetra 500 MVAr TCRAnticipated commissioning: Dec’2021 (delay due to pending supplies by GE)

DTL Peeragarhi 1x50 MVAr at 220 kVPO awarded to M/s Kanohar Electricals Ltd.

Reactive compensation at 220 kV/ 400 kV level at 15 substations

xii

xiii

xiv

xv

13x25 MVAr

Agreement signed on dt. 22.06.2020. Grant of Ist Installment received on dt.19.02.21. Bidding document is under approval.

1x125 MVAr

Agreement signed on dt. 22.06.2020. Grant of Ist Installment received on dt.19.02.21. Bidding document is under approval.

1x25 MVAr


1x25 MVAr


RAJASTHANBarmer & others

RAJASTHAN Jodhpur

RAJASTHAN Bikaner

RAJASTHAN Suratgarh

Sl.

No.Substation

Downstream

network bays

Commissioning

status of ICTs / Bays

Planned 220 kV

system

Revised

TargetRemarks

LILO of 220 kV

Bishnha – Hiranagar

D/c line.

Original schedule -

Nov'2019

Not Available Charged on11.05.2021

220 kV D/c Samba

(PG) – Samba

(JKPDD) approved in

1st NRSCT.

Not AvailableBay charged on 17.05.2021;

Line charging is remaining

220 kV New Wanpoh

-Mirbazar D/c lineNot Available

Ckt-1 has been charged;

Ckt-2 FTC is under process

at NRLDC end

220 kV Alusteng -

New Wanpoh LineNot Available Information not submitted

Shajahnapur-

Azimpur D/C lineJun'21 179th OCC

LILO of 220kV

Shajahanpur -

Sitapur at

Shajahanpur PG

Jul'21 184th OCC

4

Hamirpur

400/220 kV 2x

315 MVA S/s

(Augmentation

by 3x105 MVA

ICT)

2 nos. bays

utilized under

ISTS. Balance 6

nos to be utilized

Commissioning of ICT

1st -Dec’13

2nd - Mar’14

3rd - Mar’19

Commissioning of

Bays

4 bays - Dec’13

2 bays - Mar’14

2 bays - Mar’19

220 kV D/C Hamirpur-

Dehan line.

Original schedule:

Dec' 2020

Jun'21 180th OCC

5

Sikar

400/220kV,

1x 315 MVA S/s

2 Nos. of 220 kV

bays

Commissioned (date

not available)Not available Jul'21

Work order was placed on

dt. 13.04.2020 to M/s A to Z

Ltd. Works start on dt.

4.12.2020. S/S-32/32, T/E-

31/32 (T/E at 27 no. location

is pending due to Rajasthan

High Court stay), T/S-

2.09/8.122 km completed.

Targeted to be completed by

June’2021.

6Bhiwani

400/220kV S/s

6 nos. of 220kV

bays

Commissioned (date

not available)

220kV Bhiwani (PG) -

Isherwal (HVPNL)

D/c

line

Aug'21

Execution

delayed due to

impact of COVID19.

RK Puram –

Tughlakabad (UG

Cable) 220kv D/c line

Mar'23

Tender opened.

Under Bid

evaluation.

Masjid Mor –

Tughlakabad 220kv

D/c line

Dec'21

Tender opened.

Under Bid

evaluation.

8

400/220kV

Kala Amb GIS

(TBCB)

6 Nos. of 220kV

bays

Commissioned in

Jul'2017

220kV D/c line from

Kala Amb 400/220kV

S/s to 220/132kV

Kala Amb S/s

Dec'21

Details for utilizing

remaining 4 bays is not

available


1st & 2nd - Mar’13

3rd - Oct’16

Commissioning of

Bays Mar’13


Jul’14

Commissioning of

Bays Jul’14


Commissioning of

Bays

Jun/Sep’14

Commissioned (date

not available)

2 nos. bays

utilized under

ISTS.

Balance 4 nos. to

be utilized

6 Nos. of 220 kV

bays to be utilized

4 Nos. of 220 kV

bays to be utilized

10Nos. of 220kV

bays

400/220kV,

3x315 MVA

Samba

400/220kV,

2x315 MVA New

Wanpoh

Shahjahanpur,

2x315 MVA

400/220 kV

400/220kV

Tughlakabad

GIS

1

2

3

7

Annexure-A.II.I

भारत सरकार Government of India विद्युत मंत्रालय Ministry of ...

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