Central Electricity Authority

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1 Baart sarkar Government of India kond`iya ivavut p`aiqakrna Central Electricity Authority piscama xao~iya ivavut saimait Western Regional Power Committee ef -3, emaaayadisai xao~, AMQaorI (puva-), maumba[ F-3, MIDC Area, Andheri (East), Mumbai Aa[- esa Aao : ISO: durbaaya Phone: ; ; ; fo@sa Fax : Website : prc-wrpc@nic.in, protectionwrpc@gmail.com No. : WRPC/Protection/120 PCM/2014/1469 Date: To As per list, Sub: Minutes of 120 th Protection Committee Meeting held on 09 th January, 2014 at Mumbai - reg. Sir, Please find an enclosed herewith Minutes of 120 th Protection Committee Meeting held on 09 th of January, 2014 at WRLDC, Mumbai, Maharashtra. This is for your information and necessary action. The same is uploaded at (in news and PCM minutes) Yours faithfully, Sd/- Satyanarayan. S O. P. Singh Superintending Engineer (Protection) Encl.: As above

2 Mailing list 1) Chief Engineer (LD), MSETCL, Kalwa. Fax /65 2) Chief Engr. (Trans O&M), MSETCL, Bandra. Fax No / ) CE (W), MSEGCL, 3rd floor, Prakash gad, Mumbai. 4) S.E. (T&C), MSETCL, Aurangabad Fax / ) S.E (T&C), MSETCL, Pune. Fax / ) Dy. CE (T&C), MSETCL, Koradi, Nagpur. Fax ) S.E.(T&C), MSETCL, Nasik Road Fax ) S.E.(T&C), MSETCL, Vashi Fax ) S.E.(Testing), Bhusawal, Jalgaon Fax / ) S.E. (Task Force), MSPGCL, Nagpur Fax ) S.E.(TCC), MSETCL, Karad. Fax.No ) Chief Engineer (Gen), GSECL, H.O. Baroda. Fax / ) S.E. (Testing), GETCO, Baroda. Fax ) Chief Engineer (LD), MPPTCL, Jabalpur, Fax / ) E.D. (T&C), MPPTCL, Jabalpur. Fax ) ED (Engg.) MPPGCL, Jabalpur Fax ) Chief Engineer (LD), CSPTCL, Raipur. Fax ) C.E. (T&C), CSPTCL, Raipur.Fax ) EE (T), CSPGCL- Fax.No ) S.E. (T&C), CSPTCL, Bhilai. Fax.No ) S.E. (T&C), CSPTCL, Raipur. Fax No ) EE, Division VIII (MRT),Elect. Dept; Goa Fax ) Supdt. Engr., Electricity Dept., DNH, Silvasa. Fax : ) Executive Engr., Electricity Dept. DD. Fax: ) D.G.M. (O.S. ),N.T.P.C., Mumbai, Fax ) DGM, NTPC WR II, Raipur, Fax: ) D.G.M. (EM), KSTPS, NTPC, Korba Fax (Tele fax: ) 28) DGM (EMD), VSTPS, NTPC, Vindhyachal Fax ) DGM (EM-I), NTPC, SIPAT Fax (Tele fax: ) 30) AGM (O&M), KGPP, Adityanagar, Surat Fax / ) Sr.Supdt. (EM), Gandhar, NTPC Fax / ) DGM (O.S.), WRLDC, Mumbai Fax ) DGM, WRTS-I, POWERGRID, Nagpur, Fax / ) AGM, WRTS-II, POWERGRID, Baroda Fax (Tele fax: ) 35) SME (E), TAPS-3&4,Tarapur Fax / ) Maintenance Superintendant, TAPS 1 & 2, Tarapur.Fax ) SME(E), NPCIL, Kakrapara Fax ) GM (Maint.). TORRENT Power., Ahmedabad.Fax ) AGM (QAIT), TPC, Trombay. Fax ) Asst. VP, Dahanu TPS Fax / ) GM (O & M), Reliance Infrastructure Limited, Mumbai Fax ) GM (Electrical), JPL, Raigarh, Fax. No , ) AGM (OS), NSPCL, New Delhi. Fax.No / / ) Vice President, APL, Ahmedabad ) GM, RGPPL, Anjanwel, Guhagar, Ratnagiri, Fax.No ) GM, JSW Energy Ltd., Jindal Mansion, Mumbai- Fax.No ) GM, CGPL, Mundra Fax.No ) Director (G M Division), CEA, New Delhi. Fax.No

3 MINUTES OF THE 120 th PROTECTION COMMITTEE MEETING OF WRPC AT MUMBAI. HELD ON The 120 th meeting of the Protection sub-committee was held at WRLDC, Mumbai on The list of participant is enclosed at Annex-1. Shri S D Taksande, MS (I/C), WRPC welcomed the participants of the meeting. He informed that SR grid was synchronized with NEW grid on at 20:25 Hrs and was personally present at control room of WRLDC during the process of synchronization along with Shri. Satyanarayan S (SE), WRPC. He thanked and congratulated all the constituents of WR for their consistent cooperation within a short period of time and appreciated the efforts made by one and all for this landmark achievement. The task of preparing the SPS schemes required to be in place before synchronization of SR with NEW grid was entrusted to NLDC by Member GO&D, CEA. Accordingly the SPS was put into service by all the concerned utilities even though there were concerns by some of the utilities. These concerns would be taken up with NLDC after detailed deliberations on these schemes and hoped that NLDC would review the SPS and modify the same. He requested SE (P), WRPC to take up the agenda for discussion. ITEM NO.1: CONFIRMATION OF MINUTES OF 119 th PROTECTION COMMITTEE MEETING SE (P), WRPC stated that the minutes of 119 th PCM, held at TAPS 3&4 Tarapur were circulated vide WRPC letter No. WRPC/Protection/119 PCM/ /10195 dated and no comments have been received. The MoM circulated vide above letter was confirmed without any modifications. ITEM NO. 2: 2.1 Events of occurrence in MPPTCL Occurrence at 220 kv on at Annupur S/s: MPPTCL representative informed that on at 21:46 Hrs Y phase CT of 132 kv Annupur Rajmilan I got burst and created bus fault at 132 kv bus of Annupur S/s. This resulted in tripping of all feeders / Transformers connected to 132 kv Annupur bus from remote end in zone II. This led to overloading of 220/132 kv 63 MVA ATF and the same tripped on O/C. During this event 132 kv supply failed at ATPS, Kotma, Shahdol, Dindori and HJIM. The total load loss during this event was 35 MWHrs. All elements (except 132 kv Rajmilan- Annupur I) were restored by 23:10 Hrs on and CT was replaced on (enclosed at Annexure ). Minutes of120 th Protection Committee of WRPC held on at Mumbai 1

4 Committee felt that trippings of lines from remote ends was in order Occurrence on at 220 kv Malanpur S/s: MPPTCL representative informed that on at around 22:20 Hrs, fault occurred on 132 kv Malnpur Ambha radial feeder, but due to mechanical problem, CB did not operate and therefore the fault was not isolated. All the other lines / ICT connected to Malanpur 132 kv tripped on backup protection. Power supply was interrupted to 132 kv Ambah, Morar, Banmore, Motijheel and Morena sub stations. After rectifying the mechanical problem (SF 6 Pressure) in the breaker of the 132 kv Malnpur Ambha, all lines / ICTs were restored by 02:05 Hrs on (enclosed at Annexure ). Committee recommended utilities to carry out periodical maintenance of equipment and ascertain that all the parameters are within permissible limits Occurrence at 220 kv Shivpuri S/S on : MPPTCL representative informed that on at 17: 58 Hrs a flash over occurred on isolator of 132 kv Shivpuri - Kolaras radial feeder, creating a bus fault on 132kV Bus. All the 132 kv source feeders tripped on E/F from remote ends and the 220 kv feeders tripped from remote end on zone III. During this, power supply was interrupted to 220 kv Shivapuri S/s & 132 kv Kolaras S/s and complete supply failed to 132 kv Shivpuri. 220 kv and 132 kv systems were normalized by 18:35 Hrs. He further informed that the backup protection settings of 160 MVA transformer was on higher side and therefore resulted in tripping of 220 kv lines from remote ends. The backup protection settings of 160MVA T/F were revised (enclosed at Annexure ). Committee observed that the remote end trips were undesirable and these have occurred due to improper co-ordination of the settings Occurrence at ATPS Chachai on : MPPTCL intimated that on at 12:40 Hrs, at 132 kv Chachai S/s B phase bushing of ATF got burst and also damaged R & Y phase bushings. Following this ATPS Annupur I was tripped from ATPS, but ATPS Annupur II was not tripped. As the ATPS Annupur II was not tripped, the fault was fed to 132/220 kv TF, hence tripped and remaining feeders connected to 132 kv ATPS, Chachai were hand tripped. This led to loss of power supply to Shahdol, Kotma and Dindori sub-stations (Annexure ). The total load loss during the event was 73 MWHrs. Committee felt that, it is desirable that ATPS Annupur I & II should have tripped from 220 kv Annupur S/s, but shouldn t have tripped from 132 kv ATPS. All feeders were restored by 14:15 Hrs. Minutes of120 th Protection Committee of WRPC held on at Mumbai 2

5 2.1.5 Occurrence at Omkareshwar HPS on : WRLDC representative intimated that on at 13: 47 Hrs, 220 kv Itarsi Barwaha was tripped on fault, following this at 13:49 Hrs OSP Barwaha was tripped on O/C. At 14:05 Hrs, while 220 kv Itarsi Barwaha line was charging, 220 kv OSP-Nimrani and 220 kv OSP- Chegaon line were tripped. As already OSP - Julwania and OSP - Kandwa were kept open to control the high voltage, there were no lines to evacuate power from OSP, all the Eight Units of OSP tripped on over frequency leading to loss of 390 MWs generation (Annexure ). All elements were restored by 16:29 Hrs. Committee felt that lines, OSP Julwania and OSP Kandwa have been taken into service after tripping of OSP Barwaha on O/C Occurrence at 220 kv Omkareswar HPS on : MPPTCL intimated that on at 13:02 Hrs 220 kv OSP Nimrani, OSP Barwaha, OSP-Chhegaon and OSP Kandwa lines were tripped on O/V, led to tripping of Unit 4 & 6. This occurrence caused total loss of generation of 99 MWs (Annexure ). All elements were restored by 16:43 Hrs. Committee noted that the tripping was in order Occurrence at 400 kv Indore S/s on : MPPTCL representative informed that on at 18:24 hrs 400 kv Indore ISP was taken back into service after routine shut down, followed by normalization of Bus bar protection at 18:32 Hrs. During normalization of Bus bar protection, the busbar protection of 400 kv main bus II operated due to non operation of CT selection switchover relay. Hence bus coupler, two interconnecting transformers, 400 kv Indore Itarsi II and 400 kv Indore Asoj II got tripped but 400 kv Indore ISP I and 400 kv Indore Indore (PG) did not trip. During this incident there was no load loss. MPPTCL representative further stated that the CT switch over scheme is manual and the same is under replacement with numerical CT switching relay. The Bus bar protection scheme was installed in 1984 and CT circuit open bocking of the BB protection did not operate. The BB protection Main and Check zone operated because of differential current due to non-operation of the CT change over switch and CT ckt Open blocking feature. The BB protection has never operated for through faults in the past. The tripping links of 400 kv Indore ISP and 400 kv Indore Indore (PG) lines were isolated before normalization of bus bar protection and therefore these lines did not trip (enclosed at Annexure ). Committee observed that due care should have been taken to ensure that all the associated components of the Bus bar protection are checked before taking into service to avoid such mal operations. Minutes of120 th Protection Committee of WRPC held on at Mumbai 3

6 Occurrence on at Malanpur S/s: MPPTCL representative informed that on at 16:30 Hrs 220 kv Malanpur Auriya tripped from Auriya end as its earth wire got broken and snapped but Malanpur end CB failed to operate. Thus the fault was fed from lines connected to the 220 kv Malanpur bus, which led to tripping of connected lines from remote ends. All lines were restored by 00:15 Hrs of The load loss due this occurrence was 128 MWHrs. MPPTCL representative informed that the faulty CB at Malanpur end of 220 kv Malnpur Auriya line was replaced. He further informed that the Bus Bar protection/lbb is not in service at Malanpur and new BB protection/lbb scheme is under procurement (enclosed at Annexure ). Committee observed that LBB protection would have isolated fault earlier than the remote end trippings and MPPTCL was suggested to provide Bus bar/lbb protection at 220kV S/Ss Occurrence at 220 kv Badod S/s on MPPTCL representative informed that on at 20:04 Hrs R phase PT (Badod side) of 220 kv Badod Kota line failed, which was connected to main bus II. Metallic dome of PT and jumper came inside the zone of main bus I. This led to operation of bus bar protection on both buses. There was no loss of load/generation. All lines were restored by 21:54 Hrs. The failed PT was replaced on and 220 kv Badod Kota line was normalized at 21:09 Hrs on (enclosed at Annexure ). Committee felt that the operation of Bus Bar protection was in order Occurrence on at ATPS Chachai: MPPTCL intimated that on at 11:10 Hrs earth ground wire of 220 kv Railway traction feeder I was broken and had fallen on ground, this led to E/F. The CB of faulty feeder didn t trip, resulted in fault fed to 220 kv ATPS. The lines / Units / transformers connected to this bus tripped. The unit 5 tripped on backup e/f protection and Unit 3 tripped on low forward power flow protection. The loss of generation was 270 MWs. All elements were restored by 05:27 Hrs on (Annexure ). Committee felt that occurrence was in order Occurrence on at 220 kv Chhegaon S/s: MPPTCL representative informed that on at 08:58 Hrs, backup O/C relay of 220/132 kv, 160 MVA TF I operated, led to tripping of the transformer. This resulted in over loading of 220/132 kv, 160 MVA TF-II, hence it tripped. Prior to the occurrence, other source feeders 132 kv Chhegaon Barwaha & Barwaha Sanawad were already kept open for load management, thus 132 kv Chhegaon bus become dead. This occurrence led to total load loss of 34 MWHr. He further informed that the backup O/C relay operated while opening 132 kv Chehgaon Bharwaha line due to jerk of load shifting. The over current setting adopted for the 160MVA T/F-I was Minutes of120 th Protection Committee of WRPC held on at Mumbai 4

7 420 Amps and load on the T/F was around 400Amps. The O/C relay was found defective during subsequent testing, the same was replaced immediately i.e and system was normalized within 10 minutes i.e. 09:08 Hrs (enclosed at Annexure ). Committee observed that the operation of O/C relay was a boundary case Occurrence on at Nagda S/s: MPPTCL representative informed that on at 07:09 Hrs., 400 kv Nagda Rajgarh Ckt I was charged from 400 kv Nagda S/s end, while synchronizing it from 400 kv Rajgarh (PGCIL) S/s end, Bus Bar Protection of 400 kv Main Bus I, Nagda mal-operated and resulted in tripping of elements connected 400 kv Main Bus -I. The 400kV Nagda-Sujalpur Ckt-I tripped from both ends on DT sent which may be due to spurious signal. During this, though 400 kv main bus I become dead, load was managed by ICTs connected through tie breaker. Meanwhile, at around 07:26 Hrs, 220 kv Jaitpura Indore II tripped on E/F from Jaitpura end, due to broken jumper of R phase wave trap. This led to over loading of other lines, resulted in cascading tripping of many lines. The SPS stage 1 operated, however the load relief was not adequate. The 2 nd stage of SPS did not operate since it is designed to shed the load on O/C & Master Trip operation. The total load loss was 1195 MWs at Nagda and nearby Areas (Annexure ). All lines were restored by 11:30 hrs. MPPTCL representative further informed that the issue of mal-operation of ABB make numerical BB relay was taken up with M/s ABB. However feedback from M/s ABB is awaited and the BB scheme has been kept out of service. Committee observed that the BB protection is a mal operation. 2.2 Events of occurrence in MSETCL Occurrence on at 400/220 kv Padghe S/s: MSETCL representative stated that on at 16:19 Hrs, 400 kv Padghe Padghe HVDC II Line LBB relay operated at 400 kv Padghe s/s resulting in tripping of all the 400kV Lines & equipment connected to 400 kv Main- Bus-II. HVDC Pole-I was out for maintenance. Testing was undertaken for TRP-100 protection meant for converter T/F & Filter bus differential protection. The relay was successfully tested for Trip-A by blocking Trip-B. All the breakers were closed and Trip-B testing was undertaken by blocking Trip-A, after extending the Trip-B command, LBB of Bus-II operated, resulting in tripping all the elements connected to Main Bus-II. On detailed checking of LBB relay inspection in 400kV HVDC-II relay panel, it was found that the output contact of Y-phase current element of LBB relay was found permanently shorted, resulted in already enabled LBB current logic even though there was no current in the line CT. On receipt of the Trip-B Minutes of120 th Protection Committee of WRPC held on at Mumbai 5

8 circuit the Group-B main trip relay on 400kV HVDC-II operated. This resulted into loss of load to the tune of 32 MW on 220kV and 22 kv level (Annexure ). All lines were restored by 17:12 Hrs on Committee felt that during testing due care should have been taken while carrying out preliminary inspection of all the elements associated with the protection being tested Occurrence at 400 kv Jejuri S/s, Maharashtra on : MSETCL representative stated that on at 05:56, 400 kv Lonikhand - Jejuri Line tripped on R phase to earth fault on Zone 1 Distance Protection operation. It was followed by tripping of 400 kv Jejuri-Koyna IV from Koyna IV end on over-voltage. This led to over loading of 220 kv Kandalgaon- Lonand circuit, which was tripped from Kandalgaon on O/C protection. Thus all three feeding sources of Jejuri were tripped, led to Zero power at 400/220 kv Jejuri, 220/33 kv Jejuri, Lonand and other radially connected sub-stations and loads. The total load loss during this event was about 577 MWs. All elements were restored by 18:30 Hrs (Annexure ). Committee felt that the tripping was in order Occurrence at 220KV Amalner S/s on : MSETCL intimated that on at 23:28 Hrs, R ph CT of 220KV Amalner - Deepnagar line got burst, resulted into operation Bus Bar operation, led to tripping of all feeders connected to it (Annexure ). Committee felt that the occurrence was in order Occurrence at Nasik (Eklahare) GCR and OCR S/s on : WRLDC intimated that on at Hrs, R Phase CT of 220 kv Bus section I on Nasik GCR Side burst, resulted in operation of 220 kv Zone-A and Zone-B Bus bar protection at 220 kv Nasik GCR S/s and Bus bar protection at 220 kv Nasik OCR S/s. This has resulted in tripping of all 220 kv lines and ICTs connected to Zone A, Zone-B at 220 kv Nasik GCR S/s and all 220 kv lines and ICTs connected to 200 kv Bus of 220 kv Nasik OCR S/S. During this, Nasik Unit 5 also tripped at GCR due to loss of station supply, which was in Zone C. During the event, load loss of around 300 MW occurred along with generation loss of 428 MWs and load loss of 300 MWs (Annexure ). Committee felt that the occurrence was in order Occurrence at 400 kv Babaleswar S/s on : MSETCL intimated that on at 01:21 Hrs, jumper of B phase insulator of 220 kv Babaleswar - Alephata (connected to 220 kv Main Bus II) drop downed between 29A & 29B isolators, led to flash over. Hence, on Busbar protection operation all lines and ICTs connected to 220 kv main bus II were tripped. All Minutes of120 th Protection Committee of WRPC held on at Mumbai 6

9 elements were restored on Bus I by 03:29 Hrs and shifted to Bus II 15:07 Hrs (Annexure ). There was no load loss during the occurrence. Committee felt that the tripping was in order Occurrence at 400/220 kv Deepnagar S/s, on : WRLDC intimated that, on at 03:45 Hrs, B phase CT of Station transformer 4B (400 kv Main Bus I) got busted, this led to operation of Bus bar protection. The oil of CT spread upto R phase CT of GT5, resulted operation of differential protection of GT5, thus Unit 5 has tripped. As during this occurrence as the voltage dipped, the auxiliary supply to GT4 got failed, thus Unit 4 tripped. During this event, the total generation loss was 458 MW (Annexure ). Committee recommended the utilities to monitor CTs closely and do preventive maintenance Occurrence at 400/220 kv Chandrapur TPS on : On at 10:50 Hrs, while taking out unit 7 of Chandrapur (which was connected to main Bus I), CB of GT 7 did not operate. Due to this, LBB of GT-7 operated, resulting in tripping of all the elements connected to Bus I including Unit 3 and ST-4. Though Unit 6 was connected to Main Bus II, as its auxiliaries were fed from ST-4, it got tripped on auxiliary failure. As 400 kv Chandrapur Chandrapur II (which was connected to Bus I) tripped, overvoltage appeared at Chandrapur II, led to tripping of 400 kv Chandrapur-II Parli. This led to power re-routing and resulted in loading of Wardha flow gate and operation of its SPS, hence 84 MWs backing down at APML, Tirora. At 10:51 Hrs HVDC pole -1 was tripped on Main Circuit flow valve cooling alarm from Chandrapur end (Annexure ). GT-7 was already taken out at 09:01 hrs in the morning on BTL. Master trip relay has operted for GT-7. So, the Circuit breaker were in open condition while the isolaters were in closed condition. At 10:51 the LBB protection operated resulting in outage of all 400 kv Bus 1 elements. It was found that LBB of GT-7 has operated from PCR end. Further investigation was done to find out the exact reason why the LBB operated. The CT secondary Core 2 (used for LBB protection) whcih is laid from CTMB at GCR switchyard to Relay panel at PCR end was having zero IR value. Insulation Resistance of R phase wire was found to be zero ohm and spark was observed when earthed even after isolating from both ends. This seems to be the reason for operation of LBB protection of GT-7. The same wire was replaced with a new one and IR value were found to be ok. Minutes of120 th Protection Committee of WRPC held on at Mumbai 7

10 It was also found that, after the withdrawal of GT-7 on BTL and Master trip relay operation, it was not reset at PCR end. The Bus -1 isolator of the same was in closed condition. IF the MTR relay would have been in reset condition from PCR end immediately after GT-7 withdarawal, the event could have been avoided. MSPGCL may take proper action for resetting of MTR after withdrawal of unit to avoid any future occurrences. Committee felt that due to non-resetting of the relay and damaged cable, LBB has operated and resulted in the disturbance and suggested MSPGCL to carry out the O & M activities and testing at regular intervals Occurrence at 220 kv Chalisgaon S/s on : MSETCL intimated that on at 21:02 Hrs at 220 kv Chalisgaon S/s, CT of R phase of 132 kv Chalisgaon - CSN II got busted and also damaged nearby 132KV breaker, isolators & Y phase CT porcelain insulation. This led to operation of 132KV Busbar relay along with 132KV line differential relay of 132KV CSN Ckt-II. The 132 kv Chalisgaon - CSN II was restored by 13:58 Hrs on and all other lines were restored by 21:38 Hrs on (Annexure ). The committee felt that the Victrans make CTs has no Tan δ measuring point. Tan delta values of CT are in GST mode. In such conditions monitoring of CTs is difficult. Hence if such CTs are provided at some critical locations (as 132KV Bus at 220KV and 400KV s/s, ICT I/C and Generation attached s/s etc.) they needs replacement on priority Occurrences at Chandrapur: The occurrences in Chandrapur area of Maharastra system were minor trippings, hence enclosed at annexure Events of occurrence in CSPTCL Occurrence at JPL S/s on : On at 02:06: Hrs,, 400 kv JPL-Raipur I tripped on R-phase to earth fault, A/R operated from both ends. However, at 02:06: JPL Raipur I again tripped as fault was permanent in nature. Due to tripping of this line, SPS of Jindal operated leading to tripping of Unit 2 and generation reduction of other units by 90 MWs. At 02:44 Hrs, line was trial charged from Jindal end and due to permanent nature of fault, SOTF trip was issued at JPL end, but tripped after 500 ms. As a result, the fault was fed through 400 kv JPL Raipur II and it tripped. Due to loss of both evacuation lines, all running three units (1, 3, & 4) tripped, resulting in loss of 610 MWs generation (Annexure ). At 03:02 Hrs, 400kV JPL-Raipur II was charged from Raipur end and supply was extended to JPL Units. Unit 1 was synchronized at 07:28 Hrs while Unit 2 at 07:35 Hrs. later Unit 3 was 8 Minutes of120 th Protection Committee of WRPC held on at Mumbai

11 synchronized at 09:25 Hrs. After inspection of 400 kv JPL-Raipur 1 it was found that R phase conductor of this line snapped at a location 15 km far from JPL. After the maintenance of this line, it was taken in service at 21:10 hrs. With both line in service, Unit 4 was synchronized at 00:11 hrs on 7 th September 13. The committee felt that, the fault during the above occurrence was persisted for almost 500 ms even after operation of SOTF relay at JPL end. In view of this, JPL was advised to immediately carryout the testing of DPS of 400 kv JPL Raipur II line Occurrence at 220/132 kv Korba (East) TPS on : On around 10:03 Hrs. at 220 kv Korba (East) substation, the ground staff was instructed to open the isolator of 20 MVA ST-2 (which was out of service), instead they opened the R phase isolator of 20 MVA ST-1, which was connected to Bus -I. This led to heavy flashover and tripping of all lines/units connected to Bus I including Unit 1, 2 & 6. During this event Bango HPS also tripped which was connected to Korba (E) via Mopka. The total loss of generation was 183 MWs. All lines / units were restored by 15:55 Hrs (Annexure ). The committee recommendedto install bus bar protection at Korba(East) sub-station Occurrence at Korba NTPC on : On at 12:02 Hrs, A/R lockout occured for 400 kv Korba-Bhilai I which was on Bus II and its breaker got opened. This was followed by undesirable LBB initiation, which tripped all the elements connected with Bus II along with Bus coupler and bus sectionalizer. This led to tripping of Unit 2 & 4 connected to Bus II. The total generation loss during the occurrence was 714 MWs. All the elements were restored by 18:10 Hrs (Annexure ). The committee felt that, operation of LBB is undesirable and requested NTPC to check the healthiness of the same Occurrence on at JPL: On at 17:07 Hrs, 1500 MVA 765/400 kv ICT was charged through 400 kv JPL -Tamnar 4 line from PGCIL Tamnar end, after revision of the relay setting of ICT for backup earth fault. But it couldn t hold and ICT tripped immediately on E/F, during this tripping, a heavy dip in the system voltage was observed, which caused tripping of auxiliaries and initiation of protection elements in GRP relays of 250 MW units. At 17:36 Hrs, second trial was attempted, but resulted in tripping of JPL 250 MW Units-1 and 2 on backup earth fault. During this total generation loss was 504 MWs. All elements were restored by 19: 50Hrs (Annexure ). Minutes of120 th Protection Committee of WRPC held on at Mumbai 9

12 WRLDC representative stated that on both occasions there was a heavy voltage dip observed in the bus voltage at Raipur as seen in the recordings of PMU data. WRLDC further intimated that PGCIL was suggested not to test charge ICT, however PGCIL test charged the ICT without consulting WRLDC. Committee suggested PGCIL to test the ICT for healthiness and follow instructions of WRLDC. 2.4 Events of occurrence in GETCO Occurrence on at 400/220 kv Jetpur: On at 11:45 Hrs, heavy sparking was observed on 400 kv Bus I, Y Phase Bus L type contact at 400/220 kv Jetpur S/s. Immediately Bus coupler was hand tripped from the sub-station to isolate Bus I and Bus II in order to avoid bus fault. This led to two ICTs on Bus I without any source feeder. The third ICT connected to Bus II tripped on overcurrent protection due to overload. This resulted in load loss of around 1295 MWs and generation loss of 145 MWs (Annexure ). At 10:13 Hrs 400 kv Jetpur Mundra II was taken out under emergency shutdown for insulator replacement work, as a result around 520 MWs power was flowing through the bus coupler from 400 kv Bus I to 400 kv Bus II at Jetpur substation.. Committee noted the same Occurrence on at 400/220 kv Amreli S/s: On at 00:52 Hrs, 400/220 kv 315 MVA Amreli ICT I & II tripped on overload (The reasons for over loading may be due to increase in agriculture load as it is off-monsoon period and the wind generation had fallen drastically, led to power flow through Jetpur & Amreli). This led to loss of load at Amreli, Savarkundala, Timbdi, Dhokadva, Dhasa and nearby area in Gujarat. The total load loss during the incident was 509 MWs. All elements were restored by 01:15 Hrs (Annexure ). The committee felt that the occurrence was in order. 2.5 Events of occurrence at HVDC Bhadravathi Occurrence at HVDC Bhadrawati S/s on : On at 22:43 Hrs, due to the fault on LT cable of VCC-2, the supply switched over to redundant supply. During this, control circuit of Pump-1 malfunctioned which led to failure in switching over from half speed mode to full speed mode and got tripped. Thus HVDC Bhadravati Back to Back pole-2 tripped at 22:44 Hrs on VCC 2 Main half flow Very low alarm. The element was restored by 22:52Hrs. During this event, total load loss was 477 MWs (Annexure ). Minutes of120 th Protection Committee of WRPC held on at Mumbai 10

13 Committee felt that half speed / full speed run change over relay might be mal-operated and asked PGCIL to check its operation and replace if required Occurrence at HVDC Bhadrawati on : On at 15:50 Hrs auxiliary supply feeders (33 kv) at Warora and MIDC Chandrapur were tripped. The DG -1 & DG -2 came into service in auto mode. After restoring 33 kv MIDC feeder, auto changeover command was given, to get power from 33 kv auxiliary supply feeder and successfully took place at 16:26 hrs. After change over, there were fluctuations in the auxiliary supply. Due to this, Valve (Thyristor) cooling pumps of pole-1 & 2 got tripped, resulted in tripping of Pole-1 & 2. This resulted in loss of 978 MWs power flow to Southern region. Both poles were restored by 16:41 Hrs (Annexure ). Committee suggested that MSETCL may take up the matter with appropriate agencies (MSEDCL) to provide reliable 33 kv supply at this substation. 2.6: The status of compliance of recommendations of previous PCMs: The compliance status of recommendations of previous PCMs is enclosed at annexure 2.6. ITEM NO. 3: Tripping of lines / ICTs: The incidences of tripping of lines and ICTs during the period to are enclosed at Annexure 3. Committee noted the same. ITEM NO. 4: Status of implementation of recommendations of Report on Grid disturbance on 30 th and 31 st July 2012 in WR. The Status of implementation in WR on Recommendations of Report on Grid disturbance on 30 th and 31 st July 2012 as on is given at Annexure-4. In the 117 th PCM it was informed that CEA vide letter No. 6/AI/DST/GM-2013/ dated has forwarded formats for collecting information of status of action taken on the recommendations of the Enquiry Committee. The updated status of implementation of various recommendations of the grid disturbance enquiry committee as on 1 st & 15 th of each month is required to be forwarded to CEA by RPCs by 3 rd & 17 th of every month regularly. 1) Information in Formats 1 to 3 is to be furnished by STU and CTU for month by 1 st and 15 th of the month. 2) Information in Format 4 is to be furnished by SLDCs/ WRLDC POSOCO for the month by 1 st and 15 th of the month. Minutes of120 th Protection Committee of WRPC held on at Mumbai 11

14 3) Information in Format 5, 7 & 8 is to be furnished by WRLDC POSOCO for the month by 1 st and 15 th of the month. 4) Information in Format 6 is to be furnished by CTU for the month by 1 st and 15 th of the month. In the 117 th PCM it was decided that the above information may please be forwarded through the nodal officer of the above organizations to WRPC. Nodal officers identified for submission of data were as follows; 1. WRLDC : Shri P.Pentayya GM WRLDC 2. PGCIL-I : DGM(OS) 3. PGCIL-II: DGM(OS) 4. NTPC WR-II : Shri D.Roychowdhari AGM(OS) & A.K.Chandelia DGM(OS) 5. GETCO STU : Shri S.A.Patel. 6. GETCO SLDC : Shri B.B.Mehta, CE SLDC. 7. MSETCL STU : Shri Rajurkar SE 8. MSETCL SLDC : CE SLDC 9. MPPTCL STU : Shri Jain, CE (T&C) 10. MPPTCL SLDC:Shri P.A.R Bende CE SLDC 11. CSPTCL STU:Shri Rehman SE(T&C) 12. CSPTCL SLDC: Shri K.S.Manotia CE SLDC. SE (P), WRPC pointed out that MP is submitting the reports regularly and asked other utilities also to submit the data in prescribed format in soft copy regularly. He also pointed out that utilities may submit data to nodal agency/officer, after compiling the data and nodal agency may submit it to the WRPC, as present form of data receiving has been become difficult. The constituents agreed for the same. ITEM NO. 5: Zone 3 settings of Distance Protection Schemes: Back Ground: CEA have issued Manual on Transmission Planning Criteria which is effective from (the same is available at CEA website). Under para 20 of the Manual on Transmission Planning Criteria, guidelines on zone-iii setting to avoid tripping of lines in extreme loading conditions has been given as follows Minutes of120 th Protection Committee of WRPC held on at Mumbai 12

15 Quote 20 Guidelines for consideration of zone-3 settings 20.1 In some transmission lines, the Zone-3 relay setting may be such that it may trip under extreme loading condition. The transmission utilities should identify such relay settings and reset it at a value so that they do not trip at extreme loading of the line. For this purpose, the extreme loading may be taken as 120% of thermal current loading limit and assuming 0.9 per unit voltage (i.e. 360kV for 400kV system, 689kV for 765kV system). In case it is not practical to set the Zone-3 in the relay to take care of above, the transmission licensee/owner shall inform CEA, CTU/STU and RLDC/SLDC along with setting (primary impedance) value of the relay. Mitigating measures shall be taken at the earliest and till such time the permissible line loading for such lines would be the limit as calculated from relay impedance assuming 0.95 pu voltage, provided it is permitted by stability and voltage limit considerations as assessed through appropriate system studies. Unquote. In the 118 th PCM all the utilities confirmed that they have already taken care of the above load ability limits in deciding the Zone-3 settings. In the 119 th PCM, STUs were requested to furnish the data regarding Zone III settings in respect of intra-state lines requiring relay coordination with CTU network directly to CTU under intimation to WRPC. STUs confirmed that they would furnish the data to CTU. CTU representative said that the revised zone 3 distance protection settings of few interregional lines was not received from constituents. SE (P), WRPC stated that CTU may forward the list of lines to WR constituents and requested constituents to furnish the relevant data in this regard at the earliest. Committee noted the same. Item No 6: Testing of frequency controller and frequency limit function of HVDC back to back at Bhadravati The testing of frequency controller and frequency limit function of HVDC back to back at Bhadravati was facilitated on 22nd November 2013 between 1400 hrs to 1620hrs. POWERGRID have completed the testing on 22 nd Nov from 14:22hrs to 16:20hrs. NLDC subsequently informed settings to be adapted at HVDC Bhadravati as WR Low: 48.5 Hz, WR High: 51.5 Hz, SR Low: 48.8 Hz and SR High: 51.2 Hz. Minutes of120 th Protection Committee of WRPC held on at Mumbai 13

16 Committee noted the same. Item No 7: Commissioning of new system protection scheme in connection with synchronization of SR and NEW grid The activities associated with the synchronization are being periodically monitored by the Central Electricity Authority and the Ministry of Power. Commissioning of certain identified System Protection Schemes is one of the prerequisites for synchronization. The details of the SPS to be implemented in Western Region and the actions to be taken by different utilities were elaborated vide WRPC letter WRPC/Protection/SPS/2013/2046 dated to all the concerned. Concerns were raised by the constituents of WR pertaining to overloading in Vapi-Boisar sections, Wardha and Raipur flow gate flows, voltage conditions in Solapur area and other prevalent conditions likely to change after the synchronization. Constituents opined that matters pertaining to the SPS, Bhadravati HVDC Frequency Controller settings etc. requires the involvement of NLDC in the discussion. Also, detailed discussion on various SPS schemes formulated by CEA/NLDC is required and constituents opined that immediately a separate meeting may be called involving representatives from NLDC, PGCIL, SLDCs, WRLDC, WRPC, constituents directly involved in SPS schemes such as DB power, JPL, APL Tiroda, IEPL etc. to sort out the concerns before the NEW grid is synchronized with SR. Accordingly, a meeting was held on at WRLDC. Minutes of the meeting held on are available on WRPC website. The additional SPS schemes have been formulated at JPL, KSK Mahandi, NTPC Mauda, APL Tiroda & DB Power. Details of the same were given in Annexure-2 of the above MoM. The testing of frequency controller and frequency limit function of HVDC back to back at Bhadravati was facilitated on 22nd November 2013 between 1400 hrs to 1620hrs. POWERGRID have completed the testing on 22 nd Nov from 14:22hrs to 16:20hrs. NLDC subsequently informed settings to be adapted at HVDC Bhadravathi as WR Low: 48.5 Hz, WR High: 51.5 Hz, SR Low: 48.8 Hz and SR High: 51.2 Hz. All utilities extended their support in implementation of relevant SPS in short duration and helped the process of SR grid synchronization with NEW grid. JPL representative pointed out that SPS scheme has mal-operated twice and resulted in tripping of 660 MW Unit. He further stated that JPL is receiving only one signal which is used for 600 MWs back down at JPL. JPL representative also pointed out that though there are other generating stations in the nearby area, they were not considered for generation back-down for the said SPS. He also requested that all the Minutes of120 th Protection Committee of WRPC held on at Mumbai 14

17 generators in the W-3 bid area needs to be considered for generation back-down in proportion to their installed capacity. It was informed that two separate signals are required to be extended to JPL one for backing down of 350MW and other for backing down of 600MW. PGCIL representative informed that at present only one signal is extended to JPL which is being used for backing down/tripping of 600MW generation at JPL. Protection sub-committee decided that tentatively till two separate signals are provided at JPL (one signal to initiate 350 MWs back down and other signal to initiate 600 MWs) end, JPL may back down by 350 MWs only. PGCIL was requested to extend two separate signals to JPL at the earliest and inform in TCC/WRPC meeting. It was also decided that review of existing SPS (NLDC) will be taken with NLDC. ITEM NO 8: IMPLEMENTATION STATUS OF SPS UNDER PROGRESS: 8.1.A) SPS for 765 kv Gwalior-Agra D/C (G eneration Run back Scheme in WR): An SPS was envisaged for ensuring backing down WR generation by 500 MW (VSTPS MW, KSTPS MW, CGPL MW) in case of sudden reduction of NR import from WR on Bina-Gwalior-Agra link by 1500 MW. PGCIL vide letter No WRTS-II/VDR/O&M/AA/250 dtd (copy enclosed at Annex.-8.1.A.1) have intimated that commissioning of DTPC at Mundra would be commissioned by first week of Dec- 13. At NTPC V chal, NTPC has to lay the additional cable and confirm for further action of shifting the communication equipment and commissioning of DTPC. The cable has already been dispatched to NTPC. At NTPC Korba STPS hardware connections has to be done. In the 454 th OCC held on , CGPL representative intimated that preliminary testing had been carried out on 4th December, 2013 and final testing will be done on 27th December, NRPC vide letter NRPC/OPR/106/2012/992 dated (copy enclosed at Annex A.2) has requested to expedite the above work and commission the WR part of the SPS at the earliest. CGPL representative stated that they have made arrangement for the suitable generation backdown w.r.t. said SPS. NTPC representative stated that they have made arrangement for the suitable generation back-down at NTPC Korba and the same is under progress for NTPC Vindyachal and it will be completed by It was decided that once the entire scheme is made ready, it may be tested for its operation by PGCIL in supervision of WRLDC. It was suggested that WRLDC shall test the operation of SPS for reduced quantum s (say 50MW for each station) and not for backing down of entire 500MWs. Minutes of120 th Protection Committee of WRPC held on at Mumbai 15

18 8.1. B) SPS at APL Tiroda : A special meeting was convened by WRPC to review the SPS at APL Tiroda post synchronization of 400 kv Warora-Chandrapur-stg-II line on Following logic for SPS was accepted and same would be reviewed after commissioning of additional 400 kv line from Chandrapur-II to Warora & LILO of Parli-Chandrapur-II kV Chandrapur- 1) SLDC Maharashtra may take appropriate manual actions Warora ckt in service (such as generation pickup at Koyna, RGPPL and Parli and control generation in Wardha pocket) to relive the congestion of the corridor and load shedding in Western Maharashtra as a last resort. 2) The short term schedules shall be curtailed in the event of crossing of the margins as per the regulatory frame work. 3) Since the sensitivity of APL Tiroda generation to the Wardha flow gate is significantly low in case of Warora Chandrapur ckt in service, therefore WRLDC would suggest the factor by which the generation of APL Tiroda is required to be backed down (if it is found that the effect of backing down of generation at APL Tiroda under such condition is effective in controlling the flow through Wardha flow gate) to control incremental flow on Wardha flow gate this additional set of logic will be incorporated kV Chandrapur- 1) The SPS suggested in the meeting shall be in Warora ckt out of service operation such that in the event of tripping of Warora Chandrapur line backing down of 600MW at APL Tiroda shall be wired up. All other settings/conditions decided in the meeting shall be same. 2) In the event of tripping of Warora Chandrapur line, POWERGRID shall automatically bypass FSC on one circuit of Raipur-Wardha line. 3) This arrangement shall be implemented till the 2nd ckt of Warora Chandrapur and LILO of 2nd ckt of Chandrapur Parli at Chandrapur-II is commissioned. Further APL Tiroda was requested to incorporate additional logics as suggested by NLDC as regards to backing down of generation envisaged in SPS for SR-WR synchronization. Minutes of120 th Protection Committee of WRPC held on at Mumbai 16

19 It was decided the above SPS would be reviewed in a separate meeting consequent to commissioning of 2 nd ckt of Warora-Chandrapur and LILO of 2 nd ckt of Chandrapur Parli at Chandrapur-II. Committee noted the same. 8.1.C) SPS for CGPL units : The revised scheme as agreed in the 24 th WRPC meeting held on at Goa is as follows SPS for CGPL CGPL Gen (MWs) Chorania-1 Chorania-2 Bhachau-1 Bhachau-2 Jetpur-1 & 2 line Loading in MW Action at CGPL 1 >3100 X X > >3100 X X > >3100 X X > >3100 X X > >3100 X X > >3100 X X > >3100 >1200 Alarm for reduction in X- indicates tripping of the line. Trip mills this will reduce generation except for condition 2 where units would trip generation so that the Jetpur lines loadings are maintained around 1200 MW GETCO representative stated that Bachu Vadavi lines are extension of CGPL Bachau lines, therefore, tripping of Bachau Vadavi line needs to be incorporated in the above SPS. Committee decided that this issue would be taken up in a meeting on review of SPS in WR and noted that SPS as tabulated above has been implemented by CGPL. 8.1.D) Defense mechanism for high frequency : As per Zalte Committee report following units were identified for automatic tripping at high frequency (51.5 Hz) to help arresting the rise of frequency in case of islanding of WR from rest of NEW grid KSTPS-7 (500 MW) 2, VSTPS-7 (500 MW) 3 and CGPL-10 (830 MW). In the 24 th WRPC meeting the above generating stations requested for adding time delay for tripping and it was decided that the above units would trip at 51.5Hz with a time delay of 30sec. It was clarified during the discussions, that the generating units would sense the frequency at their ends and initiate necessary tripping. NTPC & CGPL representatives stated that they have implemented the scheme within the above time delay. Minutes of120 th Protection Committee of WRPC held on at Mumbai 17

20 8.2 Proposed SPS/Islanding scheme: 8.2.A) : SPS for reliable evacuation of Sipat generation : The SPS was discussed in the special meeting held on at TAPS 3 & 4 wherein NTPC representative made a presentation on the SPS. The group suggested that instead of tripping of 660MW, NTPC may explore other options such as HP/LP bypass so that the unit is not tripped/stressed unnecessarily. NTPC representative informed that they would revert after ascertaining the effectiveness of HP/LP bypass system. The group suggested that PCGIL would provide potential free signal at Sipat NTPC & ACIBL and necessary telemetry data of line flows. WRLDC representative stated that backing down of generation through HP/LP bypass would be a slow process and would result in overloading of the ICTs. They would give their requirement to NTPC Sipat. It was informed that ICTs can be loaded more than the rated capacity for 5-10mins depending on the ambient temperature subject to temperature rise of oil within permissible limits. NTPC representative intimated that they have received engineering approval from their corporate office for tripping of unit. A revised proposal has been sent to their corporate office for backing down of generation in line with above suggestions. Corporate approval has yet not been received. Committee decided that the above SPS would be discussed in the separate meeting. 8.2.B) : SPS at 4x300 MW Balco IPP : In the 454 th OCC meeting it was intimated that the SPS at Balco was scheduled for commissioning by Nov 2013 after commissioning of first unit of 4x300 MW Balco IPP. It was also reported that as a consequence of disconnection from Chhattisgarh, a revised islanding scheme would be in place at Balco. Further as per MOM of 17 th meeting of WR regarding connectivity/oa applications held on , Balco was asked to implement SPS to trip selected units from 4x135MW in case of load throw off of Aluminum refinery load. Member Secretary, WRPC suggested that NTPC, Balco & PGCIL meet together to device suitable scheme & implement at the earliest. Committee decided that the above SPS would be discussed in a separate meeting. 8.2.C: Islanding schemes for Nuclear Power Stations: 8.2.C.1 ) :KAPS : In pursuance with the decision in the special meeting held on at TAPS 3 & 4, SLDC GETCO and KAPS have formulated the islanding for KAPS. The same is enclosed at Annex- 8.2.C.1. Committee decided that the above islanding scheme would be discussed in a separate meeting. Minutes of120 th Protection Committee of WRPC held on at Mumbai 18

21 8.2.C.2): TAPS 1&2 Islanding: The formulation of islanding scheme for TAPS 1 & 2 was discussed in the special meeting held on at TAPS 3 & 4. The group suggested following; a) TAPS 1 & 2 islanding with Boisar load was discussed. However due to fluctuating load at Boisar (MSETCL) MIDC load it did not seem feasible, since fine generation control is not available at TAPS 1 &2. b) In view of above a it was suggested to isolate TAPS 1 &2 from MSETCL at higher frequency as a preparedness to islanding and would remain with GETCO system (i.e. Vapi-Bhilad). Subsequently TAPS 3 &4 islanding with Boisar load may be thought of. c)wrldc would prepare a scheme of isolation points and logic in consultation with GETCO, MSETCL & TAPS. d) The details of the settings would be worked out by WRLDC in consultation with GETCO, MSETCL & TAPS. Committee decided that the above islanding scheme would be discussed in a separate meeting. 8.2.C.2) TAPS 3&4 Islanding: The formulation of islanding scheme for TAPS 3 & 4 was discussed in the special meeting held on at TAPS 3 & 4. The group suggested following; a) TAPS 3 & 4 one unit to island with Boisar load and other unit to island with house load. b) WRLDC would prepare the details of the islanding scheme in consultation with GETCO, MSETCL & TAPS. c) The details of the settings would be worked out by WRLDC in consultation with GETCO, MSETCL & TAPS. Committee decided that the above islanding scheme would be discussed in a separate meeting. 8.2.D) Sugen Islanding: The formulation of islanding scheme for Sugen TPP was discussed in the special meeting held on at TAPS 3 & 4. The group suggested following: Minutes of120 th Protection Committee of WRPC held on at Mumbai 19

22 a) Isolation of feed from 220 kv Kim Sugen may be opened at higher frequency 48.2 Hzs as a preparation to islanding. b) PLC based load trimming to be implemented to match generation at Sugen, exact settings can be decided later. Committee decided that the above islanding scheme would be discussed in a separate meeting. ITEM NO. 9: Follow up items: 9.1: AUFLS Quantum & Stages A. Back ground: In the 2nd NPC meeting held on at Delhi, four (4) stages of automatic under frequency relay operation starting from 49.2 has been approved. CEA vide letter No.8/X/MMS/Gm-13/ dated , have intimated that while the process for complete implementation of UFR based load shedding may be continued so as to complete the same within three months, the frequency stages of 49.2 and 49.0 Hz with required load reliefs may be implemented by all the concerned utilities within a fortnight s time by raising the frequency settings of the existing under frequency relays suitably and compliance of the same may please be communicated to this office by 25th August The implementation of load shedding for all the four stages (i.e. 49.2, 49.0, 48.8 and 48.6Hz.) be taken up subsequently and completed by In the 24 th WRPC meeting the status was up dated as follows; 1. First two stages of AULFS setting have been already implemented by all the WR constituents. 2. Gujarat informed that they have implemented all the four stages. 3. Other Constituents agreed for implementation of other two stages by March 2014, as procurement of UFR relays is also on going. The status on implementation of the AUFLS was reviewed in the meeting held on at WRLDC Mumbai. The status updated as on is as follows. Minutes of120 th Protection Committee of WRPC held on at Mumbai 20

23 AUFLS implementation status in WR as on (All figures in MW) 49.2Hz 49.0Hz 48.8Hz 48.6Hz Actual Target Actual Target Actual Target Actual Target Gujarat Avg Peak MP Avg Peak Chattisgarh Avg Peak Maharashtra Avg Peak Goa Avg Peak DD Avg Peak DNH Avg Peak TOTAL Avg Peak GETCO, MSETCL, MPPTCL and CSPTCL representatives informed that 4 stage AUFLS scheme was implemented. CSPTCL representative stated that the quantum of AUFLS implemented in all the four stages is less than the targets given to them the same would be implemented at the earliest. Information in regards to implementation of AUFLS in respect of GOA, DD & DNH is awaited. SE (P), WRPC appreciated MSETCL, GETCO, MPPTCL and CSPTCL for implementation of 4 stage AUFLS but also expressed concern about GOA, DD & DNH as these utilities not given any information regarding the implementation status of AUFLS in their system. He requested to expedite the procurement process of the UFRs and update the status. SE (P), WRPC further requested all the constituents to give the list of the feeders with UFRs in a soft copy (excel sheet) within 15 days along with other details like peak load (MWs), average load (MWs), kv, substation etc.., He also requested utilities to furnish the details of df/dt relays to WRPC in soft copy. 9.2) Over-Voltage Protection for Transmission lines in Western Region Back ground: WRLDC vide letter WRLDC/MO-I/1658/2012/8960 dtd have intimated that, considerable number of critical 765/400 kv lines is being kept out for containing High voltage. Also there are several cases of multiple tripping of feeders emanating from a single node on over voltage. Multiple tripping on O/V at one node or in a single corridor may lead to transmission depletion adversely Minutes of120 th Protection Committee of WRPC held on at Mumbai 21

24 affecting grid security. In such cases the drop off to pick ratio should be increased to 99% while the over-voltage rating should be changed to 112 % to increase the reliability of the grid. The high drop-off to pick-up ratio of the O/V relays (say 99% and above) ensure quick reset of the relay so as to avoid multiple tripping of feeders on over voltage. For a standalone static type of relay the drop-off to pick-up ratio may be relooked and modified to 99% at all locations in WR grid by the respective utilities / constituents. In case the relay is of multi-function numerical type where the over voltage function is being utilized for O/V protection the vendor may be requested by the concerned utility to modify the ratio (drop-off to pick up) to 99%. Following nodes in western region are identified as high voltage node where line trip on over voltage protection: Chandrapur, Parli, Raigarh, Raipur, Wardha, Indirasagar, Kolhapur, Solapur, Karad, Rajgarh, Khandwa, Itarsi, Dhule, Seoni, Nagda, Kasor, Bhadrawati, Akola. Hence the above changes may be discussed in the meeting and implemented on priority. Matter may be taken as most urgent in view of reliable and secured grid operation. The matter was discussed at length in the 117 th, 118 th & 119 th PCM. a) It was informed that the maximum continuous rating of the equipments in the system is around 5% above the nominal voltage (i.e. 420kV). Further the drop off to pick up ratio hysteresis is set not just to inhibit the relay from operating but while deciding the hysteresis following factors are required to be considered; (i) The basic insulation level on which the system equipments are designed. (ii) Time to settle down the system voltages. (iii) Tripping of breakers around the safe voltage limits. Therefore adopting the setting of drop off to pick up ratio to 99%, would ensure that the line would trip (breaker opening) above 435kV, which is dangerous. Committee felt that the drop off to pick up ratio be set around 97%. b) Protection sub-committee suggested the following remedial measures; 1. The overvoltage trip setting shall be graded for magnitude and time at the nodes where sustained over voltage above nominal voltage is observed by the utilities and the settings adopted be communicated to WRPC. The time delayed overvoltage trip setting shall not exceed 110%. 2. Manual control for overvoltage shall start at 415kV and manual opening of lines on overvoltage should stop at 430kV. 3. WRLDC would carry out operation studies to identify over voltage nodes for manual control at 415kV, 420kV, 425kV and 430kV. 4. WRLDC would carry out operation studies for time co-ordination of over voltage settings. Minutes of120 th Protection Committee of WRPC held on at Mumbai 22

25 5. In addition to the lines already identified for over voltage tripping some more lines need to be identified in consultation with utilities as in present scenario after exhausting MVAR absorption by generator, line opening is only the option left to operator to contain high voltage. 6. The tap change is an operational issue and generators should set the tap(off-line) as suggested by WRLDC during opportunistic shut downs. Tap setting shall only be suggested seasonally. Committee suggested manual action to control the voltage should start from 105 % and auto line trip on over voltage should start from 106 % with appropriate voltage and time grading. The committee requested WRLDC to identify high voltage nodes and lines need to be tripped in a co-ordinated manner. Committee requested utilities to furnish the O/V relay settings of lines in their system to WRPC and WRLDC by WRPC and WRLDC would then review the existing settings and revised over voltage settings (magnitude and time graded) would then be intimated to utilities for implementing the same. However, utilities can implement their design till any review is done at WRLDC/WRPC. 9.3: Status of Bus Coupler and Bus Bar protections at S/s Back Ground: WRLDC vide letter WRLDC/MO-I/1658/2012/8960 dtd , have intimated that, there has been several occasions in the grid when the Bus Couplers and Bus-Bar Protections are kept out at substation without any intimation to WRLDC/SLDCs. In case of Bus coupler being kept out of service, all the feeders are connected on both buses. During any fault on one of the bus, it will lead to tripping of all the feeders as the fault will be fed to both buses. On the same, if Bus bar protection is kept out of service, any fault on either of bus will led to tripping of feeders on both buses. In the 118 th PCM, Chairman TCC stated that the Bus Bar protection schemes should be provided by the respective utility at the earliest, without expecting funding under R&U from MoP, GoI. The status as informed by utilities with regards to above, in the 119 th PCM is as follows: Utility Total No. of S/Ss No. of S/Ss where BB protection Balance Expected date of commissioning 400 kv 220 kv 400 kv 220 kv 400 kv 220 kv 400 kv 220 kv GETCO All 7 May 14 MSETCL All 1 Oct 13 MSPGCL All 3 MPPTCL 55 All 29 7 (Multi Bus) Mar 14 CSPTCL 16 All Mar 14 Total Committee felt that the above information be updated by utilities and requested to expedite the commissioning of BB protection wherever it was not provided. Minutes of120 th Protection Committee of WRPC held on at Mumbai 23

26 9.4: Time synchronization, non-working of DR & Main-2 of Ranchodpura line-2 at Dehgam S/s: Back Ground: PGCIL vide letter WRTS II/O&M/273/AV/1211 dated & WRTS/DEH/SS/385/113 dtd , have intimated that the pending protection issues related with GETCO bays at Dehgam S/S have not been attended so far and requested GETCO for rectification of the following issues; (i) Main-2 Distance Protection Relay (Siemens make 7SA522) of 400kV Dehgam -Ranchodpura feeder is faulty since April (ii) In all the 400kV GETCO bays (Ranchodpura-1&2, Soja, Wanakbori) at Dehgam S/S, both Main-1 & Main-2 DPRs are of same make and principle (i.e. Siemens make & 7SA522 model). The same needs to be replaced. (iii) The existing DR & its PC are not working and have become obsolete. Therefore DR needs to be configured in Main-1/Main-2 protection along with wiring of digital inputs & GPS time synchronization. In the 119 th PCM, GETCO representative informed that the time synchronization will be done within 2 months i.e. by GETCO representative informed the committee that replacement of equipment w.r.t. i & ii was already implemented and iii will be rectified by January : Auto recloser of 400kV Satpura-Koradi line: Back Ground: MPPTCL vide letter No /STP-79/487 dtd , have intimated that there is a repeated failure of auto reclose of 400kV of 400kV Satpura-Koradi line at Satpura end, since the auto reclose from Koradi end was successful on transient faults on line and requested PGCIL to attend the failure of the auto reclose at Satpura S/S. In the 118 th PCM, PGCIL representative informed that the circuit breaker replacement has been undertaken and on availability of T/B the A/R will be commissioned. The same is expected to be commissioned in August In the 119 th PCM, Committee expressed that PGCIL should put the auto recloser in service by PGCIL representative informed the committee that breaker was replaced and A/R was changed. Committee noted. 9.6): Frequent tripping of 132 kv RP Sagar-Gandhisagar line on phase to ground faults. In the 119 th PCM, WRLDC representative stated that, 132 kv Gandhisagar-RP Sagar I & II are frequently tripping on single phase to earth fault during the period of July-Aug 13.The reason for tripping of lines in transient fault need to analyzed. These lines are Inter-regional so they should be in healthy condition during operation. Committee expressed that MPSGECL and WRLDC shall Minutes of120 th Protection Committee of WRPC held on at Mumbai 24

27 take up the matter with Rajasthan and NRLDC respectively. MPSGECL and WRLDC representatives informed that the matter was taken up with their respective counter parts and stated that the frequency of tripping has reduced. Committee noted the same. 9.7) NGR bypass scheme of line reactor to convert it as bus reactor in State owned transmission lines. Back Ground: 9.7.1: Many 400 kv nodes in WR are experiencing high voltages. Several lines are kept open to control the high voltage in Western region. The line reactors of these lines are available for taking them in to service as bus reactors. PGCIL has commissioned the NGR bypass scheme to convert the line reactor as bus rector for most of the lines in WR-I and WR-II. Other constituents are also requested to expedite the same to use the line reactor as bus reactor wherever such line reactors are available. This will help in controlling the high voltage scenario in Western region : In the 119 th PCM, Committee felt that, whenever line along with its reactor is out of service and wherever NGR bypass scheme is available, the line reactor should be used as a bus reactor. However this is possible only if NGR bypass scheme is already installed on the line reactors. The need for NGR bypass requirement was also discussed and it was decided that the STUs would explore providing the NGR bypass scheme wherever possible (especially at high voltage nodes). WRLDC was requested to forward the list of lines where line reactors are required to be converted to Bus reactors. POWERGRID vide letter No WRTS II/O&M/250/ dtd (copy enclosed at Annex ), has updated the status on implementation of NGR bypass schemes implemented in WR-II of POWERGRID : It was intimated that the line reactors can be converted and used as Bus reactors only if the S/Ss have one and a half Bus Bar System and the line reactors are connected to the Bus side of the line reactor. WRLDC have forwarded list of lines (Annexure 9.7.3) where line reactors are required to be converted into bus reactors in order to control the over voltage in the system. Committee requested utilities to check the above implementation feasibility and intimate WRPC at the earliest. Minutes of120 th Protection Committee of WRPC held on at Mumbai 25

28 ITEM NO. 10: Other Items: 10.1: Provision of high speed Bus bar protection along with LBB at 132 kv stations: GETCO through vide letter no. CE (TR)/ACE (Testing)/WRPC/11/1862 dated (annexure 10.1) requested WRPC to deliberate on above subject. Few utilities expressed that there are constraints in implementation of Bus bar protection to 132 kv system like space, single bus, old existing bus bars. MSETCL informed that they are providing bus bar protection with LBB for 132 kv in case of all generating stations. SE (P), WRPC informed the committee that as per IEGC regulations, bus bar protection is mandatory for 220 kv and above substations. Hence, the committee felt that utilities themselves may decide on provision of bus bar protection to 132 kv as per the requirement of their system and state regulations. ITEM NO. 11: Date and Venue of the next meeting The date and venue for the next (121 st ) PCM will be intimated as soon it is decided. ********* Minutes of120 th Protection Committee of WRPC held on at Mumbai 26

29 Annexure-1 LIST OF PARTICIPANTS OF 120th PCM MEETING HELD ON AT WRLDC, MUMBAI Sl.No. Organisation & Name Designation Mobile No. WRPC 1 Shri S.D. Taksande M.S. ms-wrpc@nic.in Shri Satyanarayan S. S E opn-wrpc@nic.in Shri P.D.Lone E E pramod.lone@gmail.com Shri Shiva Suman A D protectionwrpc@gmail.com MSETCL/MSPGCL 5 Shri S.G. Kashikar Dy.C.E. dycetestingkoradi@gmail.com Shri S.S. Rajurkar S E se1om@mahatransco.in Shri R.H. Satpute S E setcc7500@mahatransco.in Miss S.S. Kumbhai S E se3500@mahatransco.in Miss.V.I. Mukhedkar S E se6520@mahatransco.in Shri A.V. Deo S E se4500@mahatransco.in Miss. Chimte E E ee6170@mahatransco.in Shri D.J. More E E eetic2@mahagencontps.com Shri Ashok Dhapare E E ee3150@mahatransco.in Shri Dongargaonkar Dy.E E setcc6500@mahatransco.in Shri Bharamgunde C.L. Dy. E E setcc3500@mahatransco.in Shri D.P. Nandanwar Dy. E E dyee27500@mahatransco.in MPPGCL/MPPTCL 17 Shri R.S. Shrivastava S.E. se400kvbp1@gmial.com Shri R. Shrivastava S.E. raghvensh@yahoo.in Shri Hemant Pathak S.E Shri Sunil Yadav E E setindore@yahoo.com Shri R.C. Sharma E E eesubldcind@yahoo.com CSPTCL 22 Shri N.K. Parmar E E nk.parmar@cseb.gov.in GETCO 23 Shri M U Swad E E eetestingasoj.getco@gebmail.com Shri B.M. Shah D E demissldc.getco@gebmail.com Shri K G Patel D E det.gsecl@gebmail.com WRLDC / POWERGRID 26 Shri P. Pentayya G M ppentayya@gmail.com Shri K.Muralikrishna C M mkkodakandla@gmail.com Shri Anand Dubey C M anand.dubey_pg@rediffmail.com Chitrankshi G. Sr.Er. chitra_20j@yahoo.com Shri Chandan Kumar Eng. protectionwrldc@gmail.com Shri Ravi Wadyalkar Mgr. wravi@powergridindia.com Shri Nilesh B. J E nilesh@powergridindia.com NTPC 33 Shri D.Roy Chowdhury A. G. M. ddrcc85@yahoo.in Shri A.K. Chandeliya D. G. M. akchandeliya@ntpc.co.in NPCIL 35 Shri R S Arekar SO/D rsarekar@npcil.co.in Shri Ashwin Yadav SO/E akyadav@npcil.co.in Tata Power 37 Shri M.V. Kini D.G.M. mvkini@tatapower.com Shri Alok Uppal C Mgr. uppalalok@tatapower.com Shri Girish Jawale Mgr. gtjawale@tatapower.com Torrent Power 40 Shri M.J. Modi Mgr. milindmodi@torrentpower.com Reliance Infra 41 Shri Mohan waingankar D.G.M. mohan.waingankar@relianceeada.com APL 42 Shri Uday Trivedi G M udaytrivedi@adani.com JPL 43 Shri R.K. Srivastav A G M rkshrivastava@jindalpower.com

30 Annexure 2.1.1

31 Annexure 2.1.2

32 Annexure 2.1.3

33

34

35 SINGLE LINE DIAGRAM OF OCCURRENCE AT OMKARESHWAR HPS TRIPPING OCCURRED ON DATE KV S/s Itarsi 400 KV S/s Indore (220 KV Bus) 220 KV S/s Handia 220 KV S/s Chhegaon 220 KV S/s Julwania Ckt - I Ckt - II 220 KV S/s Khandwa 3X40 MVA X'mer 220 KV S/s Barwaha (220 KV Bus) 160 MVA X'mer 220 KV S/s Barwaha (132 KV Bus) Omkareshwar Power Station (220 KV Bus - I) GEN - 7 GEN - 5 GEN - 3 GEN KV S/s Nimrani 132 KV S/s C. Khargone 132 KV S/s Sanawad Omkareshwar Power Station (220 KV Bus - II) - Breaker Close - Breaker Open - Breaker Tripped 220 KV S/s Chhegaon GEN - 8 GEN - 6 GEN - 4 GEN - 2

36 Annexure 2.1.7

37 Annexure

38 Annexure 2.1.9

39 220 KV S/s Rewa 400 KV Sukha (PGCIL) (220 KV Bus) SINGLE LINE DIAGRAM OF OCCURRENCE AT ATPS CHACHAI TRIPPING OCCURRED ON DATE KV Kotmi Kala (CSEB) { 132 KV S/s Rajmilan (MPPTCL) { 220 KV S/s Sidhi 220 KV Railway Traction - II GEN - 4 Ckt - III 220 KV Bus Coupler GEN KV Birsinghpur SGTPS (220 KV Bus) Ckt - II Fault 220 KV S/s ATPS (220 KV Bus - I) 220 KV S/s ATPS (220 KV Bus - II) 220 KV Railway Traction - I 220 KV S/s Jabalpur Ckt - I GEN KV S/s ATPS (132 KV Near Bus in NTPC System) Ckt - II 220/132 KV 63 MVA X'mer Ckt - II Ckt - I 132 KV Bus Coupler 220 KV S/s Anuppur (220 KV Bus) Ckt - I Ckt - II 220 KV S/s Anuppur (132 KV Bus) 220 KV S/s ATPS (132 KV Far Bus in M.P System) 132 KV S/s - Breaker Close - Breaker Open - Breaker Tripped 132 KV S/s HJIM (Industrial Feeder) 132 KV S/s Kotma (Radial Feeder) 132 KV S/s Dindori (Radial Feeder)

40 Annexure

41 Annexure

42 Occurrence on 23 rd August, 2013 at Padghe Substation, Maharashtra: Annexure Schematic Network Diagram:

43 Annexure Occurrence at 400/220 kv Jejuri and nearby S/s, Maharashtra on 24 th August, 2013 Schematic Network Diagram:

44 Annexure SLD OF 220KV AMLANER SUBSTATION ON DATED KV Deepnagar 220KV Bambori 220KV Dondaicha 220KV Dhule 220KV CT FAIL MAIN BUS- 220KV 220/132K ICT-I 100MVA 220/132K ICT-I I 100MVA 132KV BUS 132KV Chopda 132KV Amalner 132KV Dharangaon 132KV Nardane CB TRIP

45 CB NOT TRIP

46 Annexure Occurrence on 18 th September, 2013 at Nasik GCR and OCR S/s, Maharashtra: Schematic Network Diagram:

47 Occurrence on dated at 400 kv Babhaleshwar S/S Annexure kv Ranjangaon 220 kv Nashik kv Nagar kv BBLR kv Walunj 315 MVA, 400/220 kv, ICT MVA, 400/220 kv, ICT kv Main Bus kv B/C 220 kv Main Bus MVA, 400/220 kv, ICT-3 Bph string insulator flash over 220 kv Nashik kv Alephata 220 kv Nagar kv BBLR kv Bhenda 220 kv CSN

48 Annexure Occurrence on 1 st October, 2013 at Deepnagar S/s, Maharashtra Schematic Network Diagram:

49 Occurrence on 27 th October, 2013 at Chandrapur, Maharashtra Schematic Network Diagram: Annexure Figure 1 : Schematic Diagram of Affected Area Figure 2 : Chandrapur Sub-station prior to the event Figure 3 : Chandrapur Sub-station after the event

50 Occurrence at 220KV Chalisgaon Substation on Annexure Not Trip 220/132KV ICT-I 220/132KV ICT-II Not Trip TBC OFF 132KV Main Bus 132KV Aux. Bus R Ph CT Burst Kannad Pachora-I Pachora-II CSN-I CSN-II Dhule Manmad Pimperkhed CB Tripped

51 Occurrence at 400/200 kv JPL on 6 th September, 2013 Annexure Schematic Network Diagram:

52 Occurrence on 22 nd October, 2013 at Korba (East), Chhattisgarh Annexure Schematic Network Diagram:

53 Occurrence on 29 th October, 2013 at Korba TPS Annexure Schematic Network Diagram: Figure 1 : Schematic Diagram of Affected Area

54 Occurrence on 30 th October, 2013 at JPL Power station,tamnar Annexure Schematic Network Diagram Figure 1 : Schematic Diagram of Affected Area

55 Annexure Occurrence at 400/200 kv Jetpur and Nearby S/s, Gujarat on 31 st August, 2013 Schematic Network Diagram:

56 Occurrence at Amreli S/s and Nearby Area, Gujarat on 10 th September, 2013 Annexure Schematic Network Diagram:

57 Occurrence at Bhadrawati HVDC S/s, Maharashtra on 19 th August, 2013 Annexure Schematic Network Diagram:

58 Occurrence at Bhadrawati HVDC S/s, Maharashtra on 1 st October, 2013 Annexure Schematic Network Diagram:

59 OFFICE OF THE EXECUTIVE DIRECTOR (ENGINEERING) MADHYA PRADESH POWER GENERATING COMPANY LTD BLOCK No. - 8 & 9, SHAKTI BHAWAN, RAMPUR, JABALPUR (M. P.) cedesign_mpeb@yahoo.com Tele & Fax No /Protec./ 1529 Date : To The Superintending Engineer(Prot.) Western Region Power Committee F3, MIDC Area, Andheri (East) Mumbai Fax No E.MAIL- prc-wrpc@nic.in, devesh185@yahoo.com, mmdhakate@rediffmail.com, pramod.lone@gmail.com, ATTN. MR. M.M. DHAKATE, SUP. ENGR. (P) Sub:- Follow up of recommendation of 117 th PCM of WRPC on past occurrence. Dear Sir, *** This is with reference to follow up of recommendation of 117 th PCM of WRPC on past occurrence at ATPS, Chachai on 8 th, 12 th & 14 th Aug In this regard, it is to intimate that relay setting and testing of 132KV ATPS- Anoopur feeder has been done and found in order (for reference setting is enclosed). Regarding bus bar protection, M/s ABB Commissioning Engineer has visited the site and tested the Bus Bar and LBB protection scheme from to The bus bar scheme could not be put on service as complete scheme RADSS is obsolete and spare required are not available for replacing faulty modules and also it has become beyond repairable. Hence, M/s ABB suggested upgrading the conventional scheme to Numerical scheme. Therefore, site authorities are being requested to procure and replace Bus Bar Scheme with latest Numerical based scheme after approval from competent authority Thanking you Encl: as above Yours sincerely (S.K. SHAH) EXECUTIVE DIRECTOR (ENGINEERING) MPPGCL: JABALPUR Copy to:- 1. The Executive Director (O&M:Gen), MPPGCL, Jabalpur The Superintending Engineer (ET&I), MPPGCL, ATPS, Chachai

60 Kind Attn : Shri S. Satyanarayan S.E. (Protection) WRPC MPPTCL s FOLLOW UP OF WRPC RECOMMANDATION ON SYSTEM DISTURBANCES COVERED IN 117 th & 118 th PCCM : However it has been communicated during the 118 th & 119 th PCCM, but not linked properly and old text repeated in the minutes of 119 th PCCM. It is therefore, desired information regarding remedial actions taken on the points mentioned are as following; 2.3.4: Occurrence at 220 KV S/s Pithampur on dt WRPC Recommendation: i. Committee felt that due care should be taken during relay setting. ii. Remedial actions: Further line VTs should be installed for line protection. i. Discrepancies related to time settings and bus PT selection relay have ii. been corrected, and checked for all other elements. In MPPTCL, Bus PT arrangement is in practice for 220 KV feeders. Based on the WRPC recommendations, a proposal for line VT arrangement for line protection is submitted : Occurrence at 220 KV S/s Pithampur on dt WRPC Recommendation: i. Committee felt that OLTC Buchholz relay should not have operated. ii. Adequate load trimming scheme should be provided. Remedial actions: i. OLTC Buchholz relay operated due to heavy jerk on 132 KV feeder fault. This relay is checked for any discrepancy, it found to be in order. ii. Load dropping scheme revised, and incorporated 33 KV Metalman I & II and 33 KV Novino Industrial feeders in addition to existing 132 KV Bagadi, Betma and Jamli feeders, so that at least 120 MW load relief can be obtained in such cases : Occurrence at 220 KV S/s Pithampur on dt WRPC Recommendation: i. Committee felt that there was problem in scheme logic and same should be corrected. Remedial actions: i. GE s engineer checked the scheme and done some modifications. After through testing bus bar scheme taken in to service in May 2013.

61 2.3.9 : Occurrence at 220 KV S/s Jabalpur on dt WRPC Recommendation: i. Over flux settings of transformer need to be cheeked / tested. Remedial actions: i. Over Fluxing feature of AREVA make P633 Differential relay is used with following settings; Over Flux Alarm : 1.12 v/f reference, time delay : 15 sec. Over Flux Trip : 1.15 v/f reference, time delay : 10 sec. ii. Relay tested for over fluxing feature, and found to be operated correctly. It is under observation : Occurrence at 220 KV S/s Birsinghpur on dt WRPC Recommendation: i. Bus Bar Protection scheme should be in service. Remedial actions: i. Bus Bar Protection scheme taken in to service in July : Occurrence at 220 KV S/s Nagda on dt : Occurrence at 220 KV S/s Pandurna on dt WRPC Recommendation: i. MPPTCL should pursue suitable / timely preventive and routine maintenance of CTs. Remedial actions: i. Periodical maintenance activities for CTs also done twice a year during pre monsoon and post monsoon maintenance schedules / 18 : Occurrence at 220 KV S/s Barwaha on dt / WRPC Recommendation: i. Defective Bus Bar Protection Scheme should be repair / replace at earliest. ii. Trippings of Generator units are undesirable and settings should be reviewed Remedial actions: i. Procurement of new bus bar protection scheme is in process for 220 KV S/s Barwaha. ii. Generating units of OSP pertaining to NHDC, not to MPPGCL. NHDC should be advised to take remedial action to avoid repetition of such trippings. Similar points recorded in MOM of 116 th PCCM, NHDC may be asked to submit compliance.

62 : Occurrence at 220 KV S/s Malanpur on dt WRPC Recommendation: i. Operation of E/F relay at Malanpur and in Zone II from Gwalior (PGCIL) end ii. Remedial actions: on line fault was undesirable. Trippings of 220 KV Malanpur Auriya line from both ends was undesirable. i. ABB make REL 511 DPR at Malanpur end of the DPR found defective it is ii. replaced by SEL make DPR. To facilitate carrier aided trippings, protection couplers for Malanpur is under procurement stage. iii. Timing of Tripping of 220 Malanpur Auriya line is different and not related 118th PCM : with above trippings. 2.3: System disturbances in MPPTCL/MPPGCL system. 118 : : Occurrence on at 400kV Bina S/S,: WRPC Recommendation: Bus Bar protection should be brought into service at the earliest. Also the DPR at Guna end should be checked. Remedial actions: i. Bus Bar Protection scheme taken in to service on ii. The DPR of 220 KV Guna _ Bina I feeder operated on C Phase, Zone II correctly after this tripping 220 KV S/s Guna became a radial end, hence the DPR of 220 KV Guna_ Bina II was not operated. However DPRs at Guna end tested and found to be satisfactory.

63 S. No Tripping Restoration kv Element Actual Detail Reason of Tripping System Date Time Date Time Annexure Sarni S/s Inter-Connector I : :45 Tripped with E/F relay on Y phase from PH end. MPPGCL N STPS, Sarni Sarni S/s Inter-Connector I : :35 Interconnector-I tripped from PH end with B phase fault & E/F relay on Y phase. MPPGCL N STPS, Sarni BRS- AMK : :44 Line tripped on B Phase fault, Zone-1. MPPGCL N SGTPS, Birsinghpur Jabalpur Feeder No : :29 Line tripped on B&C phase fault, Z-2, DPR operated MPPGCL Y ATPS, Chachai Sukha Feeder : :35 Line tripped due to DPR operated MPPGCL Y ATPS, Chachai BRS- Satna : :22 Line tripped on Y and B phase fault, DPR operated, Zone-2. MPPGCL N SGTPS, Birsinghpur Sidhi Feeder : :08 Line tripped on A Phase fault, Zone-1. MPPGCL Y ATPS, Chachai Sidhi Feeder : :10 Line tripped on A Phase to Earth Fault. MPPGCL Y ATPS, Chachai Jabalpur Feeder No : :51 Line tripped due to C Phase fault, Z-1, DPR operated MPPGCL Y ATPS, Chachai Jabalpur Feeder No : :07 Line tripped on C phase fault, Z-1, DPR opeerated MPPGCL Y ATPS, Chachai BRS- Satna : :36 Line tripped on R Phase fault, Z-1, 13.3 Km from Satna end. MPPGCL N SGTPS, Birsinghpur Jabalpur Feeder No : :56 Line tripped on A Phase fault, DPR Operated, Zone-1. MPPGCL Y ATPS, Chachai Sarni S/s Inter-Connector I : :16 Tripped with E/F relay on Y phase from PH end. MPPGCL N STPS, Sarni BRS- AMK : :49 Line tripped on R phase fault, Z-1. MPPGCL N SGTPS, Birsinghpur Sidhi Feeder : :28 Line tripped on A Phase fault, Zone-1. MPPGCL Y ATPS, Chachai Sidhi Feeder : :30 Line tripped on A phase fault, Z-1. MPPGCL Y ATPS, Chachai Sidhi Feeder : :15 Line tripped on A Phase to E/F, Zone-1. MPPGCL Y ATPS, Chachai Sarni S/s Inter-Connector I : :55 Tripped with E/F relay on Y phase from PH end. MPPGCL N STPS, Sarni BRS- AMK : :51 Line tripped on R phase fault, Z-1, DPR operated MPPGCL N SGTPS, Birsinghpur Sarni - Handiya : :17 Line tripped on R Phase to E/F. MPPGCL N STPS, Sarni BRS- AMK : :19 Line triped on R phase fault, Z1, DPR operated MPPGCL N SGTPS, Birsinghpur Sarni S/s Inter-Connector I : :52 Tripped with E/F relay on Y phase from PH end. MPPGCL N STPS, Sarni Birsinghpur Feeder : :51 Line tripped on A Phase Fault, Zone-1, DPR optd. MPPGCL Y ATPS, Chachai BRS- AMK : :29 Line triped on R phase fault, Z1. MPPGCL N SGTPS, Birsinghpur BRS- SATNA : :22 Line triped on B phase fault, Z1, DPR operated MPPGCL N SGTPS, Birsinghpur BRS- AMK : :27 Line tripped on R phase fault, Z-1. MPPGCL N SGTPS, Birsinghpur Jabalpur Feeder No.I : :58 Line tripped on C Phase Fault, DPR optd. MPPGCL Y ATPS, Chachai BRS- Satna : :49 Line tripped on Y phase fault, Z-1. MPPGCL N SGTPS, Birsinghpur BRS- SATNA : :32 Line triped on B phase fault, Z1. MPPGCL N SGTPS, Birsinghpur Sarni S/s Inter-Connector I : :00 Tripped with E/F relay on Y phase from PH end. MPPGCL N STPS, Sarni Sarni - Handiya : :32 Line tripped on R&Y Phase fault. MPPGCL N STPS, Sarni Sarni S/s Inter-Connector I : :32 Line tripped on R Phase to E/F. MPPGCL N STPS, Sarni BRS- Satna : :51 Line tripped on R phase to Earth Fault, DPR operated, Zone-1 & Zone-2. MPPGCL N SGTPS, Birsinghpur Sidhi Feeder : :23 Line tripped on A Phase fault, Zone-1. MPPGCL Y ATPS, Chachai Provision of A/R Name of the Substation

64 Sidhi Feeder : :39 Line tripped on A Phase to E/F, Zone-1. MPPGCL Y ATPS, Chachai Sarni S/s Inter-Connector I : :26 Tripped with E/F relay on Y phase from PH end. MPPGCL N STPS, Sarni BRS- AMK : :01 Line tripped on B phase fault, Z-1, Dist Km from Amk end. MPPGCL N SGTPS, Birsinghpur BRS- AMK : :49 Line triped on R phase fault, Z1, DPR operated MPPGCL Y SGTPS, Birsinghpur Jabalpur Feeder No : :08 Line tripped on C phase fault MPPGCL Y ATPS, Chachai Sidhi Feeder : :31 Line tripped on A Phase to E/F, Zone-1. MPPGCL Y ATPS, Chachai BRS- AMK : :54 Line tripped on R Phase fault, Zone-2 MPPGCL N SGTPS, Birsinghpur Traction No : :03 Line tripped on R Phase fault, Z-1 MPPGCL Y ATPS, Chachai Sarni Handiya : :12 Tripped with E/F relay on Y phase from Ph end. MPPGCL N STPS, Sarni Sarni S/s Inter-connector-I : : Sarni S/s Inter-connector-II : :19 Interconnector No.1 tripped due to transient R Phase to earth fault. Interconnector No.2 tripped due to transient R Phase to earth fault. MPPGCL N STPS, Sarni MPPGCL N STPS, Sarni BRS- Satna : :11 Line tripped on B Phase fault, DPR Operated, Zone-1. MPPGCL N SGTPS, Birsinghpur BRS-AMK : :19 Line tripped on R Phase fault, Z1, 111 Km from Katni end MPPGCL N SGTPS, Birsinghpur Birsinghpur Feeder : :50 Line tripped on A phase fault, Z-2, DPR operated. MPPGCL Y ATPS, Chachai BRS- AMK : :17 Line tripped on B phase fault from Birsinghpur end.. MPPGCL N SGTPS, Birsinghpur Sukha Feeder : :32 Line tripped on B phase fault. MPPGCL Y ATPS, Chachai Sidhi Feeder : :32 Trip ABC, Z-1, Z-2 MPPGCL Y ATPS, Chachai BRS- Satna : :34 Line tripped on R phase fault, Z-1, Dist Km from Satna end. MPPGCL N SGTPS, Birsinghpur Jabalpur Feeder No : :40 Line tripped on C Phase Fault, Zone-1. MPPGCL Y ATPS, Chachai Sukha Feeder : :30 Line tripped on A Phase fault, DPR Operated, Zone-1. MPPGCL Y ATPS, Chachai Sidhi Feeder : :02 Line tripped on A phase fault, Z-1, DPR operated. MPPGCL Y ATPS, Chachai Jabalpur Feeder No : :08 Line tripped on C Phase Fault, DPR optd. MPPGCL Y ATPS, Chachai BRS-Sukha Feeder : :39 Line tripped on Y Phase to earth fault, Z1, 159 Km from Birsinghpur end MPPGCL N SGTPS, Birsinghpur BRS- SATNA : :25 Line triped on B phase fault, Z1. MPPGCL N SGTPS, Birsinghpur Sarni- I.S.P Line : :17 Line tripped on R Phase fault, Z-1, 37.5% from Sarni end. MPPGCL Y STPS Sarni Birsinghpur-Katni -II Feeder : : Sarni- Koradi Line : : Sarni- Koradi Line : : Birsinghpur-Katni -II Feeder : :45 Line tripped on Over voltage due to direct trip received from Katni end. Line tripped on over voltage due to direct trip received from Koradi end. Line tripped on overvoltage due to carrier received from Koradi end. Line tripped on Over voltage due to direct trip received from Katni end. MPPGCL Y SGTPS, Birsinghpur MPPGCL Y STPS Sarni MPPGCL Y STPS Sarni MPPGCL Y SGTPS, Birsinghpur Sarni- Koradi Line : :51 Line tripped due to direct trip received from Koradi end. MPPGCL Y STPS Sarni Birsinghpur-Katni -II Feeder : : Birsinghpur-Katni -II Feeder : :32 Line tripped on Overvoltage due to Carrier received at Birsinghpur. Line tripped on Over voltage due to direct trip received from Katni end. MPPGCL Y SGTPS, Birsinghpur MPPGCL Y SGTPS, Birsinghpur

65 Sarni- Itarsi Line : :25 Line tripped due to carrier received from Itarsi end. MPPGCL Y STPS Sarni Sarni- I.S.P Line : :08 Line tripped on Y phase fault, 41 per centage from Sarni end. MPPGCL Y STPS Sarni Sarni- Itarsi Line : :07 Line tripped due to carrier received fromsarni end. MPPGCL Y STPS Sarni Sarni- Koradi Line : : Birsinghpur-Katni -II : Birsinghpur-Katni -II : :45 Line tripped on over voltage due to direct trip received from Koradi end. Line tripped on O/V due to DT received from Katni end. Feeder not charged upto as per system requirement. Line tripped on Over voltage due to direct trip received from Katni end. MPPGCL Y STPS Sarni MPPGCL Y SGTPS, Birsinghpur MPPGCL Y SGTPS, Birsinghpur 400 Sarni- I.S.P Line : :17 Line tripped on Y phase fault, 40.5 per centage from Sarni end. MPPGCL Y STPS Sarni Sarni- I.S.P Line : :44 Line tripped on R Phase fault MPPGCL Y STPS Sarni Sarni- I.S.P Line : :45 Line tripped on R Phase fault MPPGCL Y STPS Sarni Sarni- I.S.P Line : :35 Line tripped on overvoltage due to direct trip received from ISP end. MPPGCL Y STPS Sarni Sarni- I.S.P Line : :47 Line tripped on B phase fault. Fault from Sarni end. 99.9% MPPGCL Y STPS Sarni /220 I.C.T : :42 ICT tripped due to 220KV side B phase Back up instantaneous O/C protection operated Budhipadar- Korba (E) : :18 Line tripped due to Bus fault at Korba (east) end WR I Parli-Wardha # : : Bhatapara-Bhilai : : Bhadrawati -Raipur # : : Bhatapara -Korba : : Raigarh - SEL # : :01 Line tripped on R-Y Phase fault. Fault location 121km from Wardha end. Line tripped due to R-e fault,f.l=52.6km from Bhilai end, 29km from Bhatapara Line tripped due to Spurious signal, PLCC maloperated at Raipur Line tripped due to Yph- e fault Insualtor string falshover heavy raifall & lightning at site. Line tripped due to Bph-E. fault in LILO portion of M/S SEL ltd. Fl= 18km from SEL, 101km from Raigarh DB Power-KSK : :47 Line tripped due to DT sent from DBPL end WR I DB Power-Raigarh : :35 Line tripped due to DT sent from DBPL end WR I Bhadrawati - Chandrapur # : : Bhadrawati - Chandrapur # : :52 Line tripped due to bus-bar protection operation at MSECTL Chandrapur. Line tripped due to bus-bar protection operation at MSECTL Chandrapur. 400 Bhilai -Korba # : :18 Line tripped due to Busbar protection operated at Korba end. WR I 400 Bhilai-Koradi : : Akola-Wardha # : : Bilaspur-Seoni # : :01 Line A/R successful at Bhilai end but tripped at Koradi end on Y ph- E fault. F/L=40.24Km from Bhilai end. Line tripped on Y-E fault Yph Insulator D-capped at loc. no Line tripped due to Yph-e fault F.L=190KM from Bilaspur & 142km frpm Seoni end Seoni-Khandwa I : :56 A/T on Operation of O/V Protection at Khandwa WR II Mundra-Limbdi I : :38 A/T from Limdi (GETCO) end only due to ingress of moisture in CB housing. MPPGCL Y STPS, Sarni WR I WR I WR I WR I WR I WR I WR I WR I WR I WR I WR II

66 Vindhyachal-Jabalpur I : :36 A/R successfully from both sides on Y-E Transient Fault WR II Vindhyachal-Jabalpur II : :36 A/R successfully from both sides on Y-E Transient Fault WR II Vindhyachal (NTPC) -Sasan (Reliance) : :44 A/R successfully at SASAN end only on R-ph to E/F. A/R failed at VSTPP (NTPC) end Nagda-Dehgam I : :05 A/T on B-E Fault due to Insulator Flashover. WR II Jabalpur-Itarsi II : :18 A/T on operation of O/V Protection I at Itarsi WR II Vindhyachal-Jabalpur I : :03 A/T on operation of O/V Protection at Jabalpur WR II Indore-Asoj II : :25 A/R successfully from both ends on on B-E transient fault WR II Seoni-Khandwa I : :50 A/T on operation of O/V protection at Khandwa WR II Vindhyachal - Nigrie : :04 A/T on D/T recived from Nigrie JP power Plant. WR II Satna-Bina(PG) II : :20 A/T on operation of Reactor PRV due to entry of lizard in PRD housing at Bina Vindhyachal-Jabalpur II : :57 A/T due to receipt of Direct Trip from VSTPP (NTPC) end. WR II Nagda-Dehgam II : :28 A/T on operation of O/V Protection at Nagda (MPPTCL) S/S. WR II Vindhyachal-Jabalpur I : :50 A/T on operation of O/V Protection at Jabalpur WR II Damoh-Birsinghpur I : :59 A/T due to Y-E (persisting fault) WR II Mundra-Jetpur II : :16 A/T due relay mal-operation at Mundra (CGPL) WR II Seoni-Khandwa I : :14 A/T on operation of O/V protection at Khandwa WR II Nagda-Dehgam II : :07 A/T due to transient R-N fault (Insulator flashover). WR II Mundra-Limbdi II : :06 A/T due to Bus fault at Limbdi S/S( GETCO) WR II Vindhyachal-Jabalpur I : :55 A/T tripped on DT send from Jabalpur due to DC earth leakage. WR II Itarsi-Indore II : :21 A/T due to maloperation of bus bar at Indore(MPEB) WR II Indore-Asoj II : :30 A/T due to maloperation of bus bar at Indore(MPEB) WR II Nagda-Dehgam i 06/10/13 19:23 06/10/13 19:23 A/T due to transient R-N fault (Insulator flashover) WR II Vindhyachal-Jabalpur IV 07/10/13 05:18 07/10/13 05:18 A/R successfully on B-E transient fault WR II Seoni-Khandwa I 13/10/13 02:15 13/10/13 02:25 A/T on operation of O/V protection at Khandwa WR II Indore-Asoj II 22/10/13 19:22 22/10/13 19:22 A/R successfully on Y-E transient fault WR II Damoh-Bhopal II 08/11/13 18:50 08/11/13 21:20 A/T on Y-E (transient fault) WR II Mundra-Jetpur II 14/11/13 17:47 14/11/13 18:16 A/T on operation of O/V protection at Mundra WR II Vindhyachal-Satna I 14/11/13 19:41 14/11/13 19:41 A/R successfully on R-E transient fault WR II Shujalpur-Nagda I 18/11/13 07:10 18/11/13 07:53 A/T due to operation of Busbar protection at Nagda. WR II Bhachau-Ranchodpura I 21/11/13 19:56 21/11/13 20:06 A/T on operation of O/V protection at Bhachau WR II Damoh-Birsinghpur II 23/11/13 18:24 23/11/13 19:28 A/T due to operation of Reactor Differential protection at Damoh Jabalpur-Itarsi II 30/11/13 14:38 30/11/13 14:53 A/T on B - E (persisting Fault) WR II Sasan-Satna I : :46 A/T due to mal-operation of Reactor REF protection at Satna end Bina (PG) -Indore I : :55 A/T on operation of O/V Protection at Indore WR II WR II WR II WR II WR II

67 Bina-Indore : :09 A/T on operation of O/V protection at Indore. WR II Bina-Indore : :32 A/T on operation of O/V protection at Indore. WR II Bina-Indore : :45 A/T on operation of O/V protection at Indore. WR II Bina-Indore : :12 A/T on operation of O/V protection at Indore. WR II Bina-Indore : :12 A/T on operation of O/V protection at Indore. WR II Bina (pg) -Indore I 08/10/13 04:01 08/10/13 04:11 A/T on operation of O/V protection at Indore. WR II Agra-Gwalior I 20/10/13 19:50 20/10/13 20:16 A/T on operation of O/V protection at Agra. WR II Bina (pg) -Indore I 27/10/13 03:04 27/10/13 03:14 A/T on operation of O/V protection at Indore. WR II Bina-Indore 11/11/13 19:06 11/11/13 19:16 A/T on operation of O/V protection at Indore WR II Seoni-Bina I 26/11/13 21:48 26/11/13 21:58 A/T due to operation of O/V protection at Bina WR II /220 ICT I Satna 08/11/13 10:25 Still out _ A/T due to failure of 220kV side Y-ph bushing WR II Gadchandur-Virur ckt. No R,Y,B phase pickup, general trip MSETCL Gadchandur-Virur ckt. No :20 R & E phase pickup, zone 2, general trip MSETCL Virur-Gadchiroli ckt R & E phase pickup, VT fuse failed MSETCL Gadchandur-Grace ckt Directional IDMTL earth fault relay 67N- 1flag MSETCL kV TSS Ckt. No. I : :00 O/C, E/F Prot. MSETCL kV HGT-WRR Line : :39 O/C E/F Prot. Relay MSETCL /132kV, 100 MVA ICT. II : :40 RET 67- Start LED, Master trip relay, Back Up Relay MSETCL kV HGT-B'GOAN Line : :30 Distane Relay: i) Y ph, ii) Zone 2, iii) A/R block MSETCL kV TSS Ckt. No. II : :19 Tripping Back Up Relay O/C, E/F & LBB Prot. MSETCL Gadchandur Gadchandur Gadchandur Gadchandur Hinganghat Hinganghat Hinganghat Hinganghat Hinganghat

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73 Format for Collecting information in regard to implementation of Recommendation of the Enquiry Committee. FORMAT -1 (PROTECTION AUDIT) Agency for furnishing information. Recommendation 9.1.1: There is a need to review protection schemes. This Committee concurs with recommendation of previous enquiry committee that a throrough third party protection audit need to be carried out in time bound manner. This exercise should be repeated periodically and monitored by RPC's. Action : RPCs, CTU, STUs. (D)Target date for completion of audit. (E ) No. of S/S where deficiencies detected. WR Constituent (A) Total No. of S/S in region. (B) No. of S/S identified for audit. ( C) No. of S/S yet to be audited 132 kv 220 kv 400 kv 765 kv HVDC Total 132 kv 220 kv 400 kv 765 kv HVDC Total 132 kv 220 kv 400 kv 765 kv HVDC Total Maha NA NA Guj October for 132 & 220 kv = 91 CG MPPGCL NA MPPTCL OSP ISP MP Total WR-I (PG) NA NA WR-II (PG) NA 4 WR-I (NTPC) WR-II (NTPC) Total (F) Action plan (on observation of third party protection audit) finalization date/target date for finalizing plan (G) Detail of S/S where no procuremnet is required for removal of deficiencies. No. of S/S Target date for removal of deficiencies (H) Detail of S/S where procurement is required. No. of SS Target date of removal of deficiencies. (I) Reason/remarks for rectification of deficiencies requiring period of more than one year. (J) Cost estimates for removal of deficiencies. 132 kv 220 kv 400 kv 765 kv HVDC S/S Total 132 kv 220 kv 400 kv 765 kv HVDC S/S Total 132 kv 220 kv 400 kv 765 kv HVDC S/S Total Maha NA NA NA NA NA Guj CG MP WR-I (PG) NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA WR-II (PG) WR-I (NTPC) WR-II (NTPC)

74 FORMAT -2 ( REVIEW OF ZONE - 3 PHILOSOPHY) Recommendation 9.1.2: Till protection audit is taken up, there is a need to take immediate review of zone 3 philosophy in paticular. Techniques are available to modify characteristics of the relay so that it can distinguish between load encroachment and faults. These techniques and other alternatives should be explored immediately. Action : RPCs, CTU, STUs.: Time frame : WRPC Total No. of S/S at 220 kv & above (132 KV & above in NER states, J&K, Uttarakhand, HP, Sikkims, etc) No. of sub-stations covered at each voltage level. No. of S/S where revised Z- III setting have been implemented. Month and year by when revised Z-III settings would be implemented at remaining substation. Constituent \ kv Total Total Total Total Maha Guj NA CG MPPGCL MPPTCL MP WR-I (PG) NA NA NA NA WR-II (PG) WR-I (NTPC) WR-II (NTPC)

75 Format 3 S No. Constituent No. of PMUs installed Locations Details of existing PMUs No. of PMUs functional and time syndchronised Target date for making defective PMU functional Additional PMUs planned to be insatlled No. of PMUs Locations Target date for commissioning Total No. of PMUs in the State 1 Maha Guj CG 0 4 MP 0 5 WR-I (PG) 6 WR-II (PG) WR-I (NTPC) 8 WR-II (NTPC) S No. Constituent Purpose of SPS 1 Maha 2 Guj 6 3 CG 4 MP 5 WR-I (PG) 6 WR-II (PG) 2 7 WR-I (NTPC) 8 WR-II (NTPC) SPS is already operational at present Trigger for SPS operation result of SPS operations (detailof load shedding/backing down) SPS under Implementation Details of SPS Being Planned / Under study Trigger for SPS Result of SPS Purpose operation operations Target date of Finalization of SPS Target date for commissioning of SPS Sr. No. (B) SPS already operational at present SPS Under implementation Target date of finalization of Purpose of SPS Trigger for SPS operation Result of SPS Details of SPS being planned / under study SPS operations Trigger for Result of SPS (details of load shedding Purpose SPS operation operations / backing down). 1 GETCO To restrict overloadding on 220 KV Ukai-Mota- D/C lines at Mota s/s Stage-1:-700 A, 5 Minutes. Stage-2 : 750 A, 6 sec. (It will cut off load of 66 KV System at 220 KV Mota and Ambheta S/s) Operated on Recently on , , To restrict overloadding of 220 KV D/C KAPP-Vapi line Under planning NA Target date of commissionin By end of By end of October-2013 October-2013

76 2 GETCO To restrict loading of Stage: 240 A, 5 Sec. 3 nos. of 100 MVA 220/66 KV (It will cut of load of 66 KV transformers at Bhilad Bhilad-Silvasa-1 & 66 KV s/s. Bhilad-Silvasa-2) Not operated Yet. To restrict overloadding of 400 KV S/C Hadala- Jetpur & 400 KV Hadala -Chorania Under planning NA By end of By end of October-2013 October GETCO To restrict overloadding on 220 KV Amreli- Savarkundla D/C lines Stage-1:-660 A,10 Sec. Stage-720 A, 1 sec. (It will cut off load of 66 KV System at 220 KV Savarkundla S/s) Operated on GETCO To restrict overloading Stage : 400 A, 5 Sec. of 400/220 KV 315 MVA ICT at 400 KV Amreli (It will cut of load of 66 KV S/s feeders at 400 KV Amreli s/s) Not operated Yet. 5 GETCO 6 GETCO To restrict the loading on 150 MVA, 220/132 KV ICT at 400 KV Asoj S/s in case of the sudden loss of GIPCL generation. To restrict the loading on 220/132 KV transformers at 220 KV Jambuva S/s in case of the sudden loss of GIPCL generation. Setting HV current :- 360 A Rated HV Current: 394 A (It will trip 132 KV Asoj- Manjusar line no. 1 &2. Commissioned on 23/7/13 Setting HV current :- 231 A Rated HV Current: 262 A (It will trip 132 KV Karjan, Tilakwada. 66 KV Dabhoi, 66KV Tarsali 1 &2) Commissioned on 29/7/13 Operated on Not operated Yet. 7 GETCO To restrict loading of 220 KV Hadala- Nyara 1 & 2 line at Nyara s/s Setting 720 A, 1 sec. It will trip breaker of 220 KV Kangashiyali feeder. Not operated Yet. 8 GETCO To restrict overloading of 400/220 KV ICT at 400 KV jetpur S/s Alarm Setting : 408 A, 1 sec. Tripping setting : 430 A, 5 sec. (It will trip 66 KV feeders at 400 KV Jetpur S/s.) Not operated Yet. 9 GETCO To restrict overloading of 400/220 KV ICT at 400 KV Asoj S/s Setting : 650 A, 5 Sec. (It will shed 66 KV feeders at Jambuva & Chandrapura S/s using direct trip command.) Not operated Yet.

77 10 GETCO To restrict overloading of 400 KV D/C APL- Sami-Dehgam lines without FSC. Stage-1:- 500 MW, 10 Sec - Alarm Stage-2:- 650 MW, 03 Sec - Tripping of APL Unit No. 3 or 4 Stage-3:- 750 MW, 01 Sec - Tripping of one 660 MW Unit. Most of the time, these lines remain in service with FSC only. 11 GETCO To restrict overloading of 400 KV D/C APL- Sami-Dehgam lines with FSC. Stage-1:- 500 MW, 10 Sec - Alarm Stage-2:- 750 MW, 03 Sec - Tripping of APL Unit No. 3 or 4 Stage-3:- 800 MW, 01 Sec - Tripping of one 660 MW Unit. Operated successfully many times. Recently operated on tripping APL Unit No. 4 (running at 235 MW) 12 GETCO To restrict overloading of 400 KV APL-Varsana & 400 KV APL-Hadala lines Stage-1:- 500 MW, 10 Sec - Alarm Stage-2:- 750 MW, 03 Sec - Tripping of APL Unit No. 3 or 4 Stage-3:- 850 MW, 01 Sec - Tripping of one 660 MW Unit. 13 GETCO To restrict overloading of 220 KV D/C APL- Nanikhakhar & 220 KV D/C APL-Tappar lines Stage-1:- 500 A, 05 Sec - SPS has operated Alarm successfully. Stage-2:- 550 A, 02 Sec - Tripping of any one 400/220 KV, 315 MVA ICT at APL Stage-3:- 605 A, 05 Sec - Generation backing down. Stage-4:- 670 A, 02 Sec - Tripping of APL Unit No. 1 or WR II 15 WR II 16 SPS at LANCO- Pathadi Gwalior S/S - 765kV Gwalior-Agra ckt.1 & 2 - For Load Shedding in Northern Region Gwalior S/S - 220kV Gwalior(PG)-Gwalior(MP) & Malanpur-For Tripping of 220kV Lines at Gwalior (PG) S/s in case of tripping of 765kV lines When 400kV Pathadi- Raipur trips, I unit of 300MW of LANCO has to be tripped. commissioned in Aug 2010 M/s LANC

78 SPS at JPL- Tamnar SPS at APL- Mundra SPS at HVDC, APL,Mundra If one ckt of 400kV Tamnar-Raipur trips, iunit of 250MW will trip and other 3 units would reduce by 60MW as one coal mill trips. When DCPP units are on bar, 220kV DCPP- JPL line will also trip. Details of the scheme at 400kV and 220kV are given as Annex-I Details of the scheme are given as Annex-II Sudden reduction of import by NR due to 20 tripping of Agra-Gwalior SPS for tripping I& II, a total of 500MW of Agra-Gwaliorbacking down in Western Bina lines Region automatically in Korba,Vindhyachal,Sipat, CGPL & JP Bina. If 400kV Balco- Birsighpur trips, Balco to reduce generation to 21 SPS at BALCO 100MW. If 400kV Balaco-Birsinghpur flow is more than 550MW, Balco to reduce generation by 100MW SPS at Korba Complex SPS at 765kV Sipat Power Station Total flow on Korba(E)- Raigarh + Korba(W)- Kotmikla<525MW. Details given in Annex-III. Tripping of 765kV Seoni- Bilaspur D/C. Details given in Annex-III commissioned in Sept 2011 commissioned in Aug 2011 commissioned in July12 24 SPS for CGPL In Annex-IV Proposed CGPL 25 SPS for Wardha Flow gate Proposed Proposed Proposed Proposed Proposed M/s JPL M/s APL M/s APL POWERG M/s BALC CSPTCL NTPC MSETCL Maha rastra S. NO. Voltage (kv) PMU Location Chandrapur Bhusawal New Koyna Padghe Dhule

79 6 400 Kalwa Kolapur Aurangabad Lamboti Lonikand Girwali Trombay Eklahare Boisar WR II No. of PMUs Location No. of units functional & Time Synchronised Target date to Make defective PMUs functional 1 1 Satna 1 Under Operation 2 3 Itarsi 3 Under Operation 3 2 Jabalpur 2 Under Operation 4 1 Dehgam 1 Under Operation 5 1 Vapi 1 Under Operation

80 Format - 4 (Enabling UFR and df/dt relay) Action: STUs, RPCs, Posoco, Time frame: immediate A. State wise details of UFR (as on date ) RPC (State) Total No. of UFRs installed No. of UFRs functional No. of UFRs nonfunctional Maha Guj CG MP OSP WR-I (PG) WR-II (PG) WR-I (NTPC) WR-II (NTPC) action being taken to make them functional Defective relay being replaced OEM is contacted for repairing scheme month and year to complete the remedial action B. RPC (State)State wise details of df/dt (as on date ) Details of additional UFRs under implementation/planned No. Target date of commissioning Total No. of df/dt relayss installed No. of df/dt relays functional No. of df/dt relays nonfunctional action being taken to make them functional Month and year to complete the remedial action Details of additional df/dt relays under implementation/planned No. Target date of commissioning Maha Guj OEM is contacted for repairing scheme CG MPPGCL Oct-13 OSP ISP MP WR-I (PG) WR-II (PG) WR-I (NTPC) WR-II (NTPC)

81 Format -5 Real time Security Desk POSOCO Details of real time security desk at each RLDC and NLDc Provided in WRLDC control room Action: Posoco, Time frame: 6 months Details of outage scenarios built to be used by despatcher in real time for revising TTC calculations Status of development of faster algorithm for for real time updation of TTC calculations by load despatcher under outage conditions

82 FORMAT - 6 (ADUIT OF HVDC, TCSC SVC AND PSS TUNING) Maha Guj CG MP WR-I (PG) WR-II (PG) WR-I (NTPC) WR-II (NTPC) Recommendation: : An audit of devices such as HVDC, TCSC, SVC and PSS should be done immediately to enusre that their stability features are enabled. Further exercise of PSS tuning should be planned and implemented. Settings of these dynamic stabilizing devices should be reviewed at appropriate intervals. Action : CTU, STUs, Generators: Time Frame : 6 months. (A) Audit of HVDC Location of HVDC BHADRAVATI HVDC Back to Back Audit status (completed on dd/mm/yyyy) rvations of the aduit and the name of audit ag Action plan with timeline to remove deficiencies as per audit WR-II and WRLDC Representative No discrepancy Found. Location of TCSC (B) Audit of TCSC Audit status (completed on dd/mm/yyyy) rvations of the aduit and the name of audit ag Action plan with timeline to remove deficiencies as per audit. Maha Guj CG MP WR-I (PG) Raipur TCSC WR-II and WRLDC Representative No discrepancy Found. WR-II (PG) WR-I (NTPC) WR-II (NTPC) Location of SVC Audit status (completed on dd/mm/yyyy) rvations of the aduit and the name of audit ag Action plan with timeline to remove deficiencies as per audit. Maha Guj CG MP WR-I (PG) NA NA NA NA WR-II (PG) WR-I (NTPC) ( C) Audit of SVC

83 WR-II (NTPC) RPC (state wise) Name and Location of generator identified for PSS tuning. Audit status (completed on dd/mm/yyyy) (D) Status of PSS Tuning ction plan with time line to complete PSS tuning. Maha 23 Guj CG MP OSP 1 ISP 1 WR-I (PG) NA NA NA NA WR-II (PG) WR-I (NTPC) WR-II (NTPC) Constituents Station Unit No. Capacity (MW) Gujarat Wanakbori TPS Wanakbori TPS Chattisgarh Korba (W) TPS Korba (W) TPS Korba (W) TPS Madhya Pradesh Satpura STPS Satpura STPS SGTPS Birsinghpur SGTPS Birsinghpur SGTPS Birsinghpur SGTPS Birsinghpur Maharashtra Nasik TPS Nasik TPS Parli TPS Parli TPS Parli TPS NTPC Korba STPS Korba STPS Korba STPS Korba STPS Korba STPS REL Dahanu TPS Dahanu TPS 2 250

84 Format-7 Voltage collapse prediction relay Action: RPCs, Time Frame: 1 year Status of exploration of voltage collapse prediction relay WRLDC In Boisar, A-eberle collapse prediction relay was installd on as a demo project. Currently, offline analysis is carried out by WRLDC regularly and exploring the opportunities to integrate with real time visualization software

85 Format-8 Telemetry facilities POSOCO (Region/State/ CPSU wise) GETCO MPPTCL MSETCL CSPTCL Goa DD DNH Total Name and location of Generating station / transmission element without telemetry facility Action: RPCs, Posoco, Time frame: 6 months Fault in telemetry / reason for non-availability of telemetry Nature of communication link for required telemetry in column (A) (Micro wave /fibre/plcc etc..,) Action plan with time line to operatiionalize the required telemetry facility

86 STATUS OF OPERATION OF POWER STATIONS UNDER FGMO/RGMO As on Format-09 Name of Region: Description Total No. units/station s in the region Units required co Units operate under RGMO/FGMO as per IEGC operating under RGMO Units operating in FGMO with manual intervention to archive RGMO Total No. of units under FGMO/RGMO (4+5) Units Exempted from FGMO/ RGMO by CERC Units applied to CERC for exemption/ extension Units operating with locked governors Units whose status is not available Remarks especially regarding entries, if any, in column (9) or (10) No. of Units (CS) No. of Units (SS) No. of Units (Pvt sector) No. of Stations (CS) No. of Stations (SS) No. of Stations (Pvt sector) Installed capacity CS (MW) Installed capacity SS (MW) Installed capacity FS (MW) It has been reported that there are problems associated with governors of the units indicated in column 9

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93 Annexure Lines which require NGR by pass scheme to connect line reactor as bus reactor when the line is kept out. 400 kv Lines Equipment Owner Line reactor at End 1 Line Reactor at End 2 Akola-Aurangabad-1 PGCIL Akola-Aurangabad-2 PGCIL Damoh-Bhopal 1 MPPTCL 50 Damoh-Bhopal 2 MPPTCL 50 Indore-Asoj 1 PGCIL Indore-Asoj 2 PGCIL Indore-Itarsi 1 PGCIL Indore-Itarsi 2 PGCIL Nagda-Dehgam 1 PGCIL Nagda-Dehgam 2 PGCIL Nagda-Sujalpur 1 PGCIL 50 Nagda-Sujalpur 2 PGCIL 50 Nagda-Rajgarh-1 MPPTCL 50 Nagda-Rajgarh-2 MPPTCL 50 Akola-Bhusawal S/c MSETCL 50 Chandrapur-Chandrapur II MSETCL 50 Chandrapur II-Parli 1 MSETCL 50 Chandrapur-Parli 2 MSETCL Chandrapur-Parli 3 MSETCL Karad Solapur (PG) MSETCL 50 Sub Total Total

94 GUJARAT ENERGY TRANSMISSION CORPORATION LIMITED Regd. Office: Sardar Patel Vidyut Bhavan, Race Course, VADODARA Telephone No.(0265) (D) Fax No.(0265) (GETCO) / (0265) / (GUVNL) Web site: cetr.getco@gebmail.com No. CE (TR)/ACE (Testing)/WRPC/11/1862 Date: 3/12/13 To, Superitending Engineer (Protection) Western Regional Power Committee F-3, MIDC area, Andheri (East) Mumbai Sub. Providing high speed bus bar differential protection along with LBB at 132 KV and above voltage class. Dear Sir, GETCO has implemented bus bar protection schemes in 220 KV and above voltage class substations. The implementations of bus bar schemes are as per the CEA notifications, of dated 20 th August -2010, Schedule V, regulations 43(4) (c), attached herewith. [Para-1] The Chief Electricity Authority of Gujarat State has informed that high speed bus bar differential protection scheme with local breaker back up protection shall be commissioned and always be available at all 132 KV and above voltage class substations, switching stations, generating stations connected with grid. Provided that in respect of 132 KV substations and switching stations having more than one incoming feeders. The same is as per the CEA regulations 2013(book), chapter no. VI, clause no. 45 (2) (vii). [Para-2] At present, GETCO does not have bus bar protection scheme in all 132 KV class substations as per the guide lines mentioned in [Para-1]. Further, Western Region Protection Committee (WRPC) has not given any guidelines in same context. As per the regulations mentioned in [para-2], all existing 132 KV class substations are required to be provided with high speed bus bar differential protection scheme including local breaker back up scheme. It is further to state that existing 132 KV class substations are generally single bus stations. Even, zone wise isolation for bus fault may not be possible if space of sectional isolator/breaker was not available in the switchyard. Hence, whole substation shall be entered in to the dark during failure of operation of breaker (stuck breaker) or during bus fault. It is requested to guide in the matter, so further course of action shall be finalized. Thanking You, Yours Faithfully Sd/- (U.C.Patel) Chief Engineer (TR)