Additional Agenda for 27th PSC meeting

A.2 Analysis of Tripping since last PSC

The following tripping will be discussed in detail. 

S.No.   Outage  Event  Category as per CEA Grid Standards 

Date  Time (in Hrs.) 

1  17.05.2014  21:31 hrs  Multiple element tripping at 400kV Muradnagar Station due to snapping of jumper and subsequent delayed clearance of fault. 

GD‐1 

2  18.05.2014  10:13hrs  Multiple element tripping at of 400/220kV ICTs at Moradabad Station reportedly on overload. 

GD‐1 

3  22.05.2014  09:36hrs  Multiple element tripping at 400kV Chamera‐II reportedly due to 400kV Kishenpur‐Chamera‐II line tripped on fault along with Unit ‐2 at Chamera‐II. 

GD‐1 

4  23.05.2014  15:48hrs  Multiple element tripping of 400/220kV ICTs at Lucknow(UP) Station reportedly due to overloading along with tripping of 220kV Lucknow(PG)‐Chinhat line. 

GD‐1 

5  23.05.2014  16:18hrs  Multiple element tripping at 400kV Sonepat(PG) reportedly due to snapping of Y‐phase conducter of 220kV Sonepat‐ Mohana ckt‐1 and delayed clearance of fault. 

GD‐1 

6  29.05.2014  13:19hrs  Multiple element tripping at 400kV Parichha TPS reportedly due to non‐clearance of fault from Paricha end. Bus Bar protection was out of service at the station. 

GD‐1 

7  05.06.2014  00:03hrs  Multiple element tripping at 400kV Khedar(Har) reportedly due to bursting of B‐ph CT of Bus coupler towards Main Bus‐1 & subsequent Bus Bar Protection operation for both Buses. 

GD‐1 

8  05.06.2014  01:03hrs  Multiple element tripping at 400kV Azamgarh reportedly due to damage of R‐phase Inter connecting CT of Gorakhpur line. The station has Ring Bus scheme. 

GD‐1 

9  05.06.2014  13:10hrs  Multiple element tripping at 400kV Chhabra TPS (Raj) reportedly due to tripping of 400kV Chhabra‐Bhilwara and subsequent Over voltage resulted from non‐opening of CB from Bhilwara end. 

GD‐1 

10  05.06.2014  23:56hrs  Multiple element tripping at 400kV Agra(UP) reportedly due to blast in R‐phase CT of 220kV side of 400/220kV 315MVA ICT‐I. Bus bar protection was not available at the station. 

GD‐1 

 

11  06.06.2014  11:50hrs  Multiple element tripping at 400kV Moradabad (UP) Station reportedly due to Y‐phase to ground fault in 220 kV Moradabad‐CB Ganj line. Distance protection &Backup protection did not operate .Bus bar protection is installed but not commissioned. 

GD‐1 

12  07.06.2014  00:11hrs  Multiple element tripping at 400kV Azamgarh reportedly due to damage of B‐phase main CT of Sultanpur line. The station has Ring Bus scheme. 

GD‐1 

13  07.06.2014  15:37hrs  Multiple element tripping at 400kV Daultabad (HVPNL) reportedly due to overloading. 

GD‐1 

14  08.06.2014  16:46hrs  Multiple element tripping of Unit‐1&3 at 400kV Chamera‐II(HEP) reportedly due to damage of optical fiber cable. 

GD‐1 

15  09.06.2014  20:36hrs  Multiple element tripping at 400kV Agra(UP) reportedly due to failure of R‐phase CT of 220kV side of 400/220kV 315MVA ICT‐2. Bus bar protection was not available at 220kV side of the station. 

GD‐1 

16  11.06.2014  14:41hrs  Multiple element tripping at 400kV Agra(UP) reportedly due to flashover in the B‐phase bushing of 400kV side of 400/220kV 500MVA ICT . At the same time 400/220kV 315MVA ICT‐1 & 2, tripped in cascading on overload.  

GD‐1 

17  11.06.2014  16:52hrs  Multiple element tripping at 400kV Karcham Wangtoo reportedly due to melting of Y‐phase Isolator of 400kV Abdullapur‐Karcham line. 

GD‐1 

18  12.06.2014  14:25hrs  Multiple element tripping at 400kV Gurgaon GIS reportedly due to Y‐phase to earth fault. 

GD‐1 

19  16.06.2014  12:22hrs  Multiple element tripping at 400kV Uri‐1(NHPC) reportedly due to R‐phase to ground fault and subsequent LBB protection operation. 

GD‐1 

20  19.06.2014  10:42hrs  Multiple element tripping at 400kV Parichha TPS reportedly due to snapping of Y & B phase jumper of CT for 132 kV Mauranipur feeder with non‐clearance of fault. Bus bar protection was out of service.  

GD‐1 

21  22.06.2014  13:36hrs  Multiple element tripping at 400kV Tehri HEP.  GD‐1 

22  28.06.2014  19:23hrs  Multiple element tripping at 400kV Makhu(PSEB) reportedly due to R‐phase to earth fault in 400kV Nakodar‐Makhu and mal‐operation of Bus bar protection for Bus‐2. 

GD‐1 

23  03.07.2014  22:08hrs  Multiple element tripping at 400kV Koteshwar (THDC) 

GD‐1 

24  16.07.2014  11:22hrs  Multiple element tripping at 400kV Dulhasti HEP (NHPC) reportedly due to false DT signal sent. 

GD‐1 

25  25.07.2014  11:53hrs  Multiple element tripping at 400kV Auraiya GPS(NTPC) reportedly due to L‐G fault and subsequent Bus Bar protection operation.  

GD‐1 

26  27.07.2014  18:35hrs  Multiple element tripping at 400kV Bassi(PG) reportedly on L‐G fault and Over voltage. 

GD‐1 

Concerned utilities are requested to submit the detailed report and deliberate the same in PSC

AA.1 Tripping since last PSC

NRLDC has submitted the list of tripping since last PSC meeting. The list containing all the events except those given in A.2 is enclosed as Annex-A.

All utilities are requested to analyse these events in details and submit a copy of the report to NRLDC with a copy to NRPC

AA.2 Fresh Nominations to Operation Coordination sub-Committee (OCC)

Nominations for PSC were received long back and since then many changes would have taken place in organizational structure of member utilities. Constituents are therefore requested to submit fresh nominations to the Protection Sub-Committee. As per the Northern Regional Power Committee (Conduct of Business) Rules, 2006 (Sl no. 19.2)- “ Protection Sub-Committee shall be represented by constituent members of NRPC. Other than member s of NRPC constituents, there shall be one representative each of DISCOM, IPPs less than 1000 MW and Electricity Traders in the PC. The nominated representative shall be at the level of Chief Engineers or equivalent level and concerns with power system protection / testing in the region.”

All the constituents are requested to submit nominations by 31.08.2014.

AA.3 Mock Testing of SPS meant for contingency of Mundra-Mahendergarh HVDC

Mock Testing of SPS for Mundra-Mahendergarh HVDC was carried out on 08.07.2014 wherein certain deficiencies were observed. A detailed report of the Mock test is enclosed as Annex- B.

It can be seen from the Annex-B that (i) a number of feeders in Haryana & Rajasthan are not radial (ii) number of counters increased are either more or less than envisaged for certain feeders in all States except in Haryana and (iii) the load relief that would have been available if SPS had operated on the day of testing was much lesser than envisaged in Punjab, Rajasthan and UP (iv) The scheme has not operated at Bamnauli.

In 102nd OCC meeting held on 20.08.2014 it was decided that DTL would check the system at their end. If no problem is detected then scheme for this particular sub-station would again be tested.

AA.4 Mock testing of SPS for Interruption of import by NR at 765 kV Agra (from WR), was done on 03rd April, 2014.

Mock testing of SPS for Interruption of import by NR at 765 kV Agra (from WR), was done on 03rd April, 2014. Based on the report received from the concerned utilities it came it was found that scheme is not functional at 09 out of 14 sub-stations. In a separate meeting taken by MS, NRPC on 21st July, 2014 it was decided that POWERGRID would rectify the deficiencies and would report about the functionality of the scheme within a week. As per the information submitted by POWERGRID VIDE LETTER DATED 21.08.2014, the scheme has been made functional in 08 sub-stations namely Mainpuri, Nara, Merta, Mohali Jamsher and Narwana. In the same letter, POWERGRID informed due to non-

availability of radial feeder at 220 kV Kota sub-station of RVPNL, the scheme has not been connected. Further in 102nd OCC meeting held on 20.08.2014, RVPNL informed that the feeders OCC earmarked for the SPS is normally kept radial and scheme can be wired up to the designated feeders POWERGRID may update the status

AA.5 Sub. Group discussion to decide the protection related issues of Bamnauli – Jhatikara lines.

It was decided in the 24th NRPC Protection Sub. Committee Meeting to constitute a group to look into the protection related issues of Bamnauli – Jhatikara Line consequent upon conversion of portion of overhead line to underground cable by PPCL. The report of group is enclosed as Annexure-C.

Members may deliberate

 

 

 

 

 

 

 

 

 

 

Annex-A

S.No.   Outage  Event  Category as per CEA Grid Standards 

Date  Time (in Hrs.) 

1  10.05.2014  14:40 hrs  Multiple element tripping from 220kV Moga(PSEB), Lehra Mohabbat TPS reportedly due to Bus bar protection operation. 

GD‐1 

2  12.05.2014  17.22 hrs  Multiple element tripping at 220kV Auraiya due to 3‐ph fault and GT(Generator Transformer) HV (High Voltage) side earth fault. 

GD‐1 

3  13.05.2014  05:01hrs  Multiple element tripping at 400kV Dhanoda(Haryana) reportedly due to overvoltage protection operated for 400kV Dhanoda‐Jhajjar D/C. 

GI‐2 

4  13.05.2014  20:06hrs  Multiple element tripping at 400kV Moga (PG) due to multiple phase to earth faults. 

GI‐2 

5  14.05.2014  02:01hrs  Multiple element tripping at 400kV Bassi Station reportedly due to overvoltage. 

GI‐2 

6  22.05.2014  10:05hrs  Multiple element tripping at of 400/220kV ICTs at Moradabad Station reportedly on overload. 

GD‐1 

7  23.05.2014  11:32hrs  Multiple element tripping of 220kV Unchahar‐RaiBareilly(PG) ckts reportedly due to phase to earth fault and LBB protection operation. 

GI‐1 

8  23.05.2014  16:06hrs  Multiple element tripping at 220kV Rai‐Bareilly(PG) reportedly on phase to earth fault and overcurrent. 

GD‐1 

9  24.05.2014  19:30hrs  Multiple element tripping at 220kV Kushkhera reportedly due to blasting of Y‐phase LA of 220kV Bhiwadi‐Kushkhera ckt‐1. 

GD‐1 

10  25.05.2014  19:11hrs  Multiple element tripping at 400kV Ballabhgarh reportedly due to blasting of Y‐phase LA of 400kV Ballabgarh‐Mainpuri  ckt‐2 along with mal‐operation of Bus bar protection. 

GI‐2 

11  29.05.2014  11:56hrs  Multiple element tripping of all three ckts of 220kV Unchahar‐RaiBareilly(PG) reportedly due to phase to earth fault. 

GI‐1 

12  31.05.2014  14:11hrs  Multiple element tripping at 220kV section of 400kV Mandola reportedly due to phase to earth fault and mal‐operation of Protection relay. 

GD‐1 

13  31.05.2014  17:35hrs  Multiple element tripping of 400kV Mainpuri‐Parichha D/C reportedly due to collapse of towers. 

GI‐2 

14  01.06.2014  19:53hrs  Multiple element tripping at 765kV Bhiwani(PG) reportedly due to Phase to earth fault. 

GI‐2 

15  01.06.2014  21:47hrs  Complete Blackout at 220kV Samaypur(BBMB) Station reportedly due to delayed clearance of fault resulting in Bus Bar protection operation. 

GD‐1 

16  03.06.2014  14:25hrs  Multiple element tripping of 220kV Unchahar‐Raibareilly ckt‐2&3. 

GI‐1 

17  05.06.2014  22:49 hrs  Multiple element tripping of 220kV Bamnoli‐Dial ckt2 along with other causing voltage dip in nearby nodes. 

GD‐1 

18  06.06.2014  13:25 hrs  Multiple element tripping at 400kV Singrauli TPS. 

GI‐2 

19  06.06.2014  17:06hrs  Multiple element tripping at 400kV Sikar(PG) reportedly of 400kV Agra‐Sikar D/C on B‐phase to earth fault and 400kV Sikar‐Neemrana D/C on overvoltage. 

GI‐2 

20  07.06.2014  18:17hrs  Multiple element tripping at 220kV Bhatinda & Lehra Mohabbat TPS(PSEB) reportedly due to fault in 220kV Bay‐2 of 100MVA ICT at Bhatinda TPS.  

GD‐1 

21  10.06.2014  13:14hrs  Multiple element tripping at 220kV Panipat (HVPNL), reportedly due to blast of Y‐phase CT of 220/132kV ICT at  Safidon S/S. 

GD‐1 

22  12.06.2014  17:51 hrs  Multiple element tripping at 765kV Unnao(UP) reportedly due to R phase to earth fault and Overcurrent protection. 

GI‐2 

23  13.06.2014  17:45hrs  Multiple element tripping of 400/220kV, 315MVA ICT‐1&5 at 400kV Mandola reportedly due to operation of PRD. 

GI‐2 

24  13.06.2014  18:19hrs  Multiple element tripping of 400kV Kaithal‐Patiala D/C ckt reportedly due to tower collapse. 

GI‐2 

25  13.06.2014  19:32hrs  Multiple element tripping at 400kV Shahjhapur (PG) reportedly on transient fault. 

GI‐2 

26  13.06.2014  20:44hrs  Multiple element tripping of 400kV Muradnagar‐Panki on Y‐phase to earth fault & 400kV Unnao‐Panki on over reach setting of relay at Panki end. 

GI‐2 

27  21.06.2014  12:10hrs  Multiple element tripping of Unit‐1,2&4 at 220kV Anta GPS. 

GD‐1 

28  21.06.2014  16:31hrs  Multiple element tripping of 400kV Fatehpur‐Mainpuri D/C reportedly on phase to phase fault. 

GI‐2 

28  24.06.2014  09:34hrs  Multiple element tripping in Rajasthan & wind generation Loss reportedly due to clearance of fault in zone‐2 in 220kV Akal‐Bhu line (Jumper at Bhu end snapped). LVRT setting problem of Wind turbine 

GD‐1 

30  29.06.2014  01:06hrs  Multiple element tripping of 400kV Bhiwani‐Jind D/C reportedly due to tower collapse and fell on 400kV Bhiwadi‐Moga D/C, resulted in tripping of 400kV Bhiwadi‐Moga D/C also. 

GI‐2 

31  02.07.2014  14:03hrs  Tower of 220kV Wazirabad‐Kashmiri gate D/C collapsed and fell on 220kV Wazirabad‐Geeta Colony D/C resulted into tripping of all 4 ckt's 

GD‐1 

32  05.07.2014  16:30hrs  Tripping of 400kV Jhajjar‐Mundka D/C  GI‐2 

33  11.07.2014  23:24hrs  Multiple element tripping at 220kV Khetri(Raj) reportedly due to Bus bar operation. 

GD‐1 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

34  12.07.2014  05:25hrs  Multiple element tripping at 220kV Moga (PSEB) reportedly due to failure of CT of Y‐ph at Moga (PSEB). 

GD‐1 

35  13.07.2014  18:32hrs  Multiple element tripping at 220kV Nara (UP) reportedly due to transient fault. 

GD‐1 

36  20.07.2014  21:35hrs  Multiple element tripping at 400kV Dhanonda (HVPNL) reportedly due to damage of isolator of 400kV Mohindergarh‐Dhanonda ckt‐1. 

GI‐2 

37  21.07.2014  17:36hrs  Multiple element tripping of 220kV AD Hydro & 132kV Malana‐II reportedly due to single line to ground fault in 220kV AD Hydro‐Chhaur ckt. 

GD‐1 

38  21.07.2014  15:06hrs  Multiple element tripping at 220kV Pampore(J&K) reportedly due to R‐phase to ground fault in 220kV Mirbazar‐Pampore ckt‐2. 

GD‐1 

39  27.07.2014  17:17hrs  Multiple element tripping at 220kV Gorakhpur (UP) reportedly on Y‐ph to earth fault. 

GD‐1 

40  28.07.2014  18:58hrs  Multiple element tripping at 400kV Muradnagar(UP) reportedly due to R‐phase to ground fault. 

GI‐2 

 

Annex-B

State    Case 1

Case 2

Case 3

Case 4

Remarks

Haryana  Load relief envisaged (MW)  

150 300 600 700 Non-Radial feeders 1. 220kV-Lula Ahir Ckt-I&II of 400kV S/S Dhanunda 2. 132kV Dadri-Kalanor Ckt of 132kV S/S Charkhi-Dadri 3. 220kV PGCIL Ckt-I&II of 220kV S/S Nuna Majra  

Load relief that would have been obtained in mock testing (MW)  

0 0 244 244

Punjab  Load relief envisaged (MW)  

50  100  200  300  Counter increment more than the required at 66 kV Talwara-2 feeder of 220kV S/S Gobindgarh -1 66kV Gill Road Ckt-I & 66kV Dugri of 220kV S/S LaltonKalan

Load relief that would have been obtained in mock testing (MW)  

40  80  123.75  170.6 

Rajasthan  Load relief envisaged (MW)  

50  100  200  300  Non-radial feeders at Alwar S/s 132kV Alwar-Bansur, 132kV Alwar- Ramgarh, 132kV Alwar- Malakhera, 132kV Alwar-Mandawar 132kV Lamaba ,132kV Gotan & 132 Ratangarh-Sardarshahar Counter increment more than the required at Alwar S/s 132kV Alwar (Local), 132kV Alwar-Bansur, 132kVAlwar-Malakhera &132kV Alwar-Ramgarh feeders

Load relief that would have been obtained in mock testing (MW)  

0  0  75  147 

Uttar Pradesh 

Load relief envisaged (MW)  

50  100  200  300  Counter increment less than required at 132kV Thana bhawan & 132kV Jasala

Load relief that would have been obtained in mock testing (MW)

0  30  65  0 

Delhi  Load relief envisaged (MW)  

0  0  200  300  SPS not operated at 400/220kV Sub-Station Bamnauli  Load relief that would

have been obtained in mock testing (MW)  

0  0  0  287