Address List - Southern Regional Power Committee¤•ेंद्र तनदे क,...
Transcript of Address List - Southern Regional Power Committee¤•ेंद्र तनदे क,...
पता सूचि / Address List
1. मुख ्य अमभयंता ( एिपीसी ि जऱ पररयोजना) एपीजेनको, हैदराबाद / Chief Engineer (Generation I),
APGENCO, Hyderabad
2. मुख्य अमभयंता (पररयोजना), एपीजेनको, हैदराबाद/ Chief Engineer (Projects), APGENCO, Hyderabad
3. मुख्य अमभयंता ( विद्युत प्रणाऱी), एपीट्रान्स्को, हैदराबाद/ Chief Engineer (Power System),
APTRANSCO, Hyderabad.
4. मुख्य अमभयंता ( उत्पादन), टीएसजेनको, हैदराबाद/ Chief Engineer (Generation), TSGENCO,
Hyderabad
5. मुख्य अमभयंता (पररयोजना), टीएसजेनको, हैदराबाद/ Chief Engineer (Projects), TSGENCO, Hyderabad
6. मुख्य अमभयंता ( विद्युत प्रणाऱी), टीएसट्रान्स्को, हैदराबाद/ Chief Engineer (Power System),
TSTRANSCO, Hyderabad
7. मुख्य अमभयंता (इऱे.डडजाईन), केपीसीएऱ, बेंगऱूर/ Chief Engineer (Ele. Designs), KPCL, Bangalore
8. मुख्य अमभयंता ( आर टी), केपीटीसीएऱ, बेंगऱूर/ Chief Engineer (RT), KPTCL, Bangalore
9. मुख्य अमभयंता, एसएऱडीसी, केपीटीसीएऱ, बेंगऱूर/ Chief Engineer, SLDC, KPTCL, Bangalore
10. मुख्य अमभयंता ( एनसीटीपीएस-।।), टैनजोडको, िैन्नै/ Chief Engineer (NCTPS-
II),TANGEDCO,Chennai
11. मुख्य अमभयंता (संरऺण एिं संिार), टी एन ई बी, िने्नै/ Chief Engineer (Protection & Communication),
TANTRANSCO, Chennai
12. मुख्य अमभयंता (पारेषण), प्रणाऱी प्रिाऱन, एिएमटी काऱोनी, केएसईबी, कऱमस्सेरी-683503/ Chief Engineer
(Transmission) System Operation, HMT Colony, KSEB, Kalamassery-683503
13. मुख्य अमभयंता (पारेषण) एनपीसीआईएऱ, मुंबई/ Chief Engineer (Transmission), NPCIL, Mumbai.
14. अपर तनदेशक (पररयोजना), पीसीकेएऱ, बेंगऱूर-9/ Additional Director (Projects), PCKL,Bangalore-9
15. महाप्रबंिक ( ओ एस), एनटीपीसी, दक्षऺण ऺेत्रीय मुख्याऱय, मसकंदराबाद/ General Manager (OS), NTPC
SRHQ, Secunderabad
16. अिीऺण अमभयंता (विद्युत), केपीसीएऱ, बेंगऱूर/ Superintending Engineer (El.), KPCL, Bangalore
17. अिीऺण अमभयंता ( विद्युत), मुख्य अमभयंता ( आरटी) का कायासऱय, केपीटीसीएऱ, बेंगऱूर/ Superintending
Engineer (El.), KPTCL, O/o Chief Engineer (RT), KPTCL, Bangalore
18. जी एम ( प्रिा ि अनु) दऺ-े।, पािरधिड, मसकंदराबाद/ GM (O&M), SR-I, PGCIL, Secunderabad
19. जी एम ( प्रिा ि अनु) दऺ-े।।, पािरधिड, बेंगऱूर/ GM (O&M), SR-II, PGCIL, Bangalore
20. श्री पी पी जेस्टीन, एजीएम ( ईएम), एनटीईसीएऱ, िने्नै-103/ Shri P.P.Gestine, AGM (EM), NTECL,
Chennai-103.
21. श्री ई सिींद्र कुमार, सी. एम. (विद्यतु ), टीपीएस-। विस्तार, एनएऱसी, नैिेऱी- 607807/ E. Sachindra Kumar,
CM (Electrical), TPS-I Expn. NLC, Neyveli-607807 (Fax No: 04142 – 257944)
22. कें द्र तनदेशक, केजीएस 3 ि 4, कैगा, कनासटक/ Station Director, KGS 3&4, Kaiga, Karnataka
23. अनुरऺण अिीऺक, केजीएस 1 ि 2 , कैगा कनासटक/ Maintenance Superintendent, KGS 1&2, Kaiga,
Karnataka.
24. अनुरऺण अिीऺक, एमएपीएस, कऱ्पक्कम/ Maintenance Superintendent, MAPS, Kalpakkam
25. अनुरऺण अिीऺक, केकेएनपी, ततरुनऱ्िेऱी न्जऱा, तममऱनाडु- 627106/ Maintenance Superintendent,
KKNP, Thirunelveli Dist,TN-627106
26. कायसकारी अमभयंता (पी ि एमडी), मुख्य अमभयंता (जी) का कायासऱय, मूऱमट्टम, केएसईबी, इडुक्की न्जऱ्ऱा/ EE
(P&MD), O/o CE (G), Moolamattom, KSEB, Idukki (dist) - 685589
27. कायसकारी अमभयंता/ प्रभागीय ईएििी, विद्युत विभाग, पुदिुरेी/ EE/ Div EHV, Electricity Department,
Puducherry
28. श्री सतीष न्जंदऱ, सीईओ, जेएसडब्ऱ्यू एनजी मऱ. नई ददऱ्ऱी–110066/Shri Satish Jindal, CEO, M/s JSW
Energy Ltd, New Delhi-110066
29. श्री िीरेश देिरमनी, उ म प्र, जेएसडऱ्ब्यू एनजी मऱ. तोरणगऱ्ऱू. बेऱ्ऱारी- 583275/ Shri Veeresh Devaramani,
DGM, M/s JSW Energy Ltd, Toranagallu, Bellary-583275
30. श्री आर िी भट्टए, उपाि्यऺ ( प्रिाऱन) यूपीसीएऱ, बेंगऱूर/ Shri R.V.Bhat, Vice President (Operations),
UPCL, Bangalore
31. सह उपाध्यrऺ ( संरऺण ि मीटररगं) , अदानी पािर मऱ , 8-ए , 'संभि' जज भिन के सामने , बोदकदेि , अहमदाबाद- 380015 , गुजरात / Associate Vice President (Protection & Metering), Adani Power
Ltd, 8-A, ‘Sambhav,’ Opp. Judge’s Bungalow, Bodakdev, Ahmedabad 380 015, Gujarat, India
*****
SOUTHERN REGIONAL POWER COMMITTEE
BENGALURU
Agenda for the 48
th Meeting of Protection Coordination Sub-Committee of
SRPC to be held on 29.10.2015 (Thursday)
1. Introduction
2. Confirmation of Minutes of last PCSC meeting
Confirmation of minutes of 47th
Protection Coordination Sub-Committee meeting
held on 15.09.2015.
3. Grid Occurrences
3.1 Grid Disturbance (GD), Grid Incidences (GI), and trippings due to failure of Auto-
reclosing (A/R), and Mal-operation of PLCC equipment that occurred during the
last one-month period (August - October, 2015) would be discussed in the PCSC meeting [Annexure-I].
Constituents are requested to furnish the following information in respect of the
above grid occurrences to have fruitful discussions in the PCSC forum.
(a) Single line diagram of the station with switching devices, CT, PT and relay
details.
(b) Cause of the tripping & Remedial Action taken
(c) Relay setting details
(d) Deficiencies / Observations as perceived by the Utility which needs PCSC’s
intervention.
Constituents are requested to bring/ give full particulars for the tripping events
incident to their system.
3.2 In compliance of Regulations 5.2 (r) of IEGC, the Constituents are requested to furnish the following information in respect of Grid Occurrences (Annexure-II)
latest by 20.10.2015:
(a) First Information Report (FIR)
(b) Event Logger (EL) output
(c) Disturbance Recorder (DR) output
(d) Trip event analysis report (with pre and post fault system conditions)
Non-furnishing of Tripping details including Disturbance Recorder/Sequential
Event logger output would be discussed in the meeting.
4. Submission of reports/compliance by Constituents
4.1 Status of pending Protection Coordination Sub-Committee (PCSC)
Recommendations
Status of the pending PCSC recommendations (from 30th
PCSC to 47th
PCSC) given at Annexure-III may please be sent latest by 26.10.2015.
Agenda for the 48th Protection Coordination Sub Committee Meeting to be held on 29-10-2015 Page 2
4.2 Remedial measures for "Transmission Line under Forced Outage"
The constituents are requested to send the remedial measures/ actions taken by them for the tripping events as circulated vide our emails. (Annexure-IV)
The trip events are based on the daily reports at SRLDC website
http://srldc.in/DailyReport.aspx under the menu: Reports->Daily-> "TL under
Forced Outage")
4.3 Certificate for Healthiness of Batteries
As per the MoP direction given in pursuant to recommendations of the
Enquiry Committee (NEW grid disturbance on 30th
& 31st July, 2012), RPC’s
are required to obtain from their respective Constituents the monthly
certificate for healthiness of batteries, installed at 220 KV and above voltage
level Substations (for power supply to Relays, RTUs and PLCC equipment)
and furnish the same to CEA/ MoP.
With reference to above, the Constituents are requested to submit the
certificate on healthiness of batteries on monthly basis (i.e. on 7th
day of the
month) to SRPC.
The sought status for the month of September, 2015 is still awaited from the
following SR-Constituents:
APTRANSCO, TSGENCO (Thermal & Hydro), KPTCL, TANGEDCO,
KSEB, PED, PGCIL (SR-II), NTPC (Ramagundam), NTPL, SEL, CEPL,
MEPL & TPCIL.
5. SPS for contingency of 400 Nellore-NPS lines
It is to bring to your kind notice that continuous high flows in the order of 600 MW to
900 MW are being observed in each of the 400kV Nellore-NPS D/C lines. The issue of
over loading of these lines was also discussed in PCSC-47 held on 15.09.2015, when it
was opined to put in place an SPS to deal with system security issues that may arise on
account of tripping of one of the lines. The ‘N-1’ thermal limit of these lines (quad
Moose) is assumed as 1700 MW. However, in the event of tripping of one of 400kV
Nellore (PG) - NPS D/C lines, ‘N-1’ security of the system will be breached as the flow
on the second line crosses the thermal limit.
Presently, generation from TPCIL, MEPL and SEPL (2000 MW approx.) is being
evacuated through these lines and the situation would only get aggravated in the absence
of generation at Krishnapatnam TPS (SDSTPS). Further, generation (amounting to 600
MW) from NCC TPS, which is expected to be commissioned in March, 2016, would also
have to be evacuated through these lines.
Considering above factors and in the interest of operational security of the grid to make
it ‘N-1’ secure, it is proposed to provide an SPS for contingency of one of 400kV NPS -
Nellore (PG) D/C lines. The SPS, which necessitates backing down/ generation tripping
of 650 to 750 MW at SEPL, MEPL and TPCIL power stations, would be presented along
with study results by SRLDC for discussion and approval.
Agenda for the 48th Protection Coordination Sub Committee Meeting to be held on 29-10-2015 Page 3
6. Provision of line differential protection for 400 kV Nellore-NPS D/C lines
The 400 kV Nellore (PG) - NPS lines being of short length, need for provision of line
differential protection (Main-1& Main-2) for the same has been emphasized and
discussed in several PCSC meeting of SRPC. There have been few cases in the recent past
also where distance relay at NPS/ Nellore (PG) over-reached and tripped for remote end
faults.
1. 400kV NPS-Nellore lines tripped on zone-2 from NPS end during tripping at
Krishnaptnam TPS at 18:20 hrs on 8.09.2015.
2. Line tripped at NPS end only and was holding from Nellore during CT failure at
MEPL station at 20:38 hrs on 20-05-2015
Considering their importance in grid, it is necessary to avoid unwarranted tripping of
these lines. As such, the line differential protection for these lines is envisaged to avoid
mal-operation of protection system.
7. Review of implementation of certain Protection Audit Recommendations of SR-
Constituents
Based on the status updates received from APGENCO, TANGEDCO, TANTRANSCO
w.r.t. implementation of protection audit recommendations of their stations, certain recommendations, as brought out in Annexure-V, are proposed to be reviewed for
implementation.
8. Network Configuration changes
As per the information furnished by SR-Constituents to the OCC forum in their 110th
meeting held on 06.08.2015 (Minutes circulated on 27.08.2015) and 111th meeting held
on 08.09.2015 (Minutes circulated on 28.09.2015), the following network configuration
changes (additions/ deletions/ modifications of transmission elements) took place in the
southern grid during the months of July-September, 2015.
The following assets under “ Transmission System associated with System
Strengthening –XVIII in SR grid “ along with Communication Signal from sending end
to receiving end, metering, telemetry and protection system had been put under COD
8th August 2015 (charged on 4th August 2015) :
400 kV Vijayawada (Nunna PG) - Nellore (APTRANSCO) Ckt-III along with
1 x 63MVAR line reactor.
400 kV Vijayawada (VTPS)-Nellore (APTRANSCO) along with 1 x 63
MVAR line reactor.
9.6 MW Wind Generation capacity was added in Tamil Nadu during the month of
July 2015.
COD of LANCO St-3 Unit 3A was declared on 11-08-2015.
COD of Unit II (800 MW) of SDSTPP (Krishnapatnam JV) of APGENCO was
declared on 24-08-2015 from 00:00 hrs.
Unit I (600 MW) of IL &FS was synchronized to grid on 05.08.2015.
Unit II (500 MW) of NTPL was declared COD on 29-08-2015 from 00:00 hrs.
Subsequently Unit II (660 MW) of TPCIL was declared COD w.e.f. 00:00 hrs of 15-
09-2015.
0.75 MW Wind Generation Capacity was added in Tamil Nadu during the month of
August, 2015.
Agenda for the 48th Protection Coordination Sub Committee Meeting to be held on 29-10-2015 Page 4
9. Compliance of Hon’ble CERC Orders.
9.1 Petition No. 146/MP/2013 with I.A. 36/2013: Order dated 20.02.2014
Compliance of Regulations 5.2 (r) of the Grid Code: Issue regarding non-
furnishing of FIR / Trip Analysis Report, EL, DR, etc. was also
highlighted. It is pointed out that the above reports are to be submitted /
uploaded on SRLDC web application within 24 hours as mandated under
IEGC / CEA Regulations.
Implementation of Phase-I and Phase-II of Protection Audit
Recommendations: All the constituents are requested to submit the updated
status of the compliance (those who have not completed recommendations
mentioned in the Phase I and Phase II) to SRPC Secretariat at the earliest.
Compliance of Regulations 5.2 (e) & 5.2 (l) of the Grid Code and Regulation
3(1)(e) of CEA Grid Standards: The constituents are requested to strictly
comply with these provisions by ensuring standard protections systems having
the reliability, selectivity, speed and sensitivity to isolate the faulty equipment
and protect all components from any type of faults, within the specified fault
clearance time and providing protection coordination
Ensuring proper maintenance of transmission lines and adopting best O&M
practices: The constituents are requested to conduct line patrolling regularly
as per the SRPC transmission line patrolling guidelines (available under the
menu item "All Uploads Operation Miscellaneous Transmission Line
Patrolling Protocol / Guidelines for Southern Region" on SRPC website).
(http://www.srpc.kar.nic.in/website/2014/operation/patrolling.pdf).
9.2 Petition No. 167/Suo- Motu/2012: Order dated 22.02.2014
The Constituents are requested to follow approved protection philosophy
ISTS licensees are requested to submit details of updated distance protection relay
setting of all inter-regional lines to POSOCO & RPCs.
All SLDCs are requested to install/activate sound recording system in their control
rooms within three months from the date of issue of this order.
The Constituents are requested to submit the progress of implementation to
SRPC and SRLDC as specified in the Hon'ble CERC Order.
9.3 Petition No. 263/MP/2012: Order dated 19.12.2013
Constituents are requested to implement the quantum of relief by AUFR and df/dt
relays by identifying additional feeders and keep them functional within one month
of issuing this order.
SLDCs are also requested to map these relays on their respective SCADA
system within three months of issuance of this order.
The Constituents are requested to submit the progress of implementation to
SRPC and SRLDC as specified in the Hon'ble CERC Order.
9.4 APTRANSCO’s Petition No.95/MP/2015: Date of hearing 09-04-2015
It was noted in the Analysis and Decision part of the Order that:
“8. Noting the submissions of the petitioner, SRPC and SRLDC and activities
initiated by the petitioner for procurement of materials required for
implementation of the remarks of protecting audit, we allow time to the
petitioner till 31.12.2015 for completion of our directions in Order dated
19.12.2013 in Petition No. 146/MP/2013.”
Agenda for the 48th Protection Coordination Sub Committee Meeting to be held on 29-10-2015 Page 5
“9. SRPC is directed to monitor the status of completion of works relating to
protection audit remarks in respect of 7 nos 400 kV sub-stations and 11 nos
220 kV sub-stations of APTRANSCO, protection audit remarks in Protection
Coordination Sub-Committee (PCSC) meetings and coordinate the periodic
protection audit to be carried out in Southern Region after deliberation in
SRPC and submit bi-monthly report to the Commission.”
9.5 TSTRANSCO’s Petition No.83/MP/2015: Order dated 14-05-2015
It was noted in the Order that:
“12. Noting the submission of the petitioner, SRLDC and SRPC and
considering the actions already initiated by the petitioner for implementation
of works relating to protection audit, we allow time till 31.10.2015 and
31.8.2016 for implementation of Phase-I and Phase -II works respectively.
The petitioner is directed to submit affidavit confirming the completion of
Phase I of protection audit remarks by 31.10.2015 and Phase-II of protection
audit remarks by 31.8.2016.
13. SRPC is directed to monitor the status of completion of remarks in these
substations vis-à-vis protection audit remarks in Protection Coordination Sub
Committee (PCSC) meetings. SRPC is further directed to coordinate the
periodic protection audit to be carried out in Southern Region after
deliberation in SRPC.”
9.6 Order in Petition No. 86/MP/2014 and 374/MP/2014: Order dated 18-08-2015
The time-lines given to the various SR-Constituents for completion of Phase-I and
Phase-II activities of Protection Audit Recommendations are given below:
(A) KSEBL:
18. Noting the submission of KSEBL, SRLDC and SRPC and considering the actions
already initiated by KSEBL for implementation of remarks of protection audit, we
allow time till 31.12.2015 and 31.3.2016 for implementation of Phase-II works
and R&M works at Idduki HEP respectively.
(B) TANTRANSCO: 21. After considering the submissions of TANTRANSCO, SRLDC and SRPC, it is noted
that TANTRANSCO`s request for time till 31.5.2015 for implementation of Phase–I
activities of providing numerical relays for feeder protection and Auto transformer
protection is already over. We allow time till 30.6.2016 for other Phase-I activities
such as provision of line VT, 5 core CT, Time synchronizing with GPS, Disturbance
recorder & event logger and Phase-II activities. According to SRLDC, total
implementation period is 15 to 16 months for items which involve major
procurement, design changes with major site modification/civil activities.
Accordingly, we allow 16 months time i.e up to 30.11.2016, for Renovation and
Modernization of Singarpet, Singaperumalkoil, Salem and Tondiarpet 230 kV sub-
stations from the issue of the order.
(C) NLC:
22. NLC has sought time upto 31.12.2014 and 31.3.2015 for completion of Phase-I work
of Numerical Relay Retrofitting and for Phase-II works of providing second battery
bank of PLCC respectively. It is noted that the completion dates for Phase-I and
Phase-II of protection audit remarks as requested by NLC are already over.
Agenda for the 48th Protection Coordination Sub Committee Meeting to be held on 29-10-2015 Page 6
Therefore, no direction is required in this regard. However, we direct NLC to file a
confirmation report regarding completion of protection audit works for Phase-I and
Phase-II.
(D) KPTCL:
23. …
…
Considering the submission of KPTCL and SRLDC, we allow time to KPTCL time till
15.01.2016 for completion of Phase-I and Phase-II of protection audit remarks. No
further extension shall be granted in this regard.
(E) KPCL:
24. …
… Considering the submission of KPCL and SRLDC, we allow time to KPCL till
31.10.2015 and 31.12.2015 for completion of Phase-I for Phase-II of protection
audit remarks respectively. No further extension shall be granted in this regard.
26. We direct SRPC to (a) submit status of protection audit remarks in respect of
APGENCO, NTPC (SR), Talcher, Puducherry, PGCIL (SRTS I & II), MAPS and
TANGEDCO, (b) monitor the status of completion of remarks of protection audit in
respect of all constituents of Southern Region in Protection Coordination Sub-
Committee (PCSC) meetings, and (c) to coordinate periodic protection audit to be
carried out in Southern Region after deliberation in SRPC. All the constituents of
Southern Region are directed to file their status with SRPC on regular basis to
facilitate proper monitoring in PCSC meetings. SRPC is directed to submit bi-
annually status report to the Commission confirming the completion of Phase-I,
Phase-II and R&M works of protection audit remarks of the constituents of Southern
Region.
10. Other Protection Issues, if any, with the permission of the Chair
11. Sending Agenda items for the PCSC meetings
As per the Guidelines of CEA/MOP, it has been decided to conduct the PCSC
meetings on monthly basis. It is requested that Agenda Items for the PCSC meetings,
if any, may please be sent latest by 5th
working day of the month to SRPC Secretariat
to compile and circulate the same so as to have fruitful discussions in the PCSC
meetings.
12. Date of next PCSC meeting
The 49th
PCSC meeting would be conducted on 30.11.2015 (Monday) at UPCL,
Mangalore, Karnataka.
*******
Grid Occurrences
For all tripping events involving failure of substation equipment, Constituents are
requested to kindly furnish the SLD or equivalent pictorial representation showing
(i) Location of the fault, and (ii) Bus-bar arrangement/ Configuration of feeders and
other connected equipment with proper CB positions (OPEN/ CLOSE) at the time of
occurrence of the fault.
1. ग्रिडडडस्टर्बन्स / ग्रिडइन्सडन्टकावििरण - Details of Grid Disturbances:
Sr. No.
क्र.सं. घटनाकावििरण /
Details of Event
तारीख/ Date &
समय /Time कारण / Reason
टटप्पणी /Remarks
शे्रणी/ Category
1
Disturbance in
220kV Tamilnadu
system
05-09-2015
at 14:04 hrs
Complete outage of 230kV
Palladam, Othakalmandapam
S/s, Coimbatore S/s, Thudialur
and Sadayapalayam S/s
GD-1
2
Complete outage of
220kV Peenya
Substation in
Karnataka
27-09-2015
at 4:23:17
hrs
all connected 220kV lines and
transformers were taken on
220kV North bus as South bus
was under shut down for
conversion of strung bus to rigid
bus and isolator replacement
under R&M works. Failure of
HV side Y phase CT of
150MVA Transformer-3
occurred at Peenya Substation
which resulted in operation of
Differential and HV REF
protection. The failure of CT
also resulted in a 220kV bus
fault in North Bus
GD-1
3
Outage of 220kV
Ambewadi station
in Karnataka
30-09-2015
at 10:41 hrs
220kV Ambewadi-Nagjheri line-
2 tripped on B-phase to earth
fault. This resulted in loss of
supply to 220kV Ambewadi bus.
220kV Ambewadi-Ponda line-
1&2 were hand tripped after
deenergization of bus at
Ambewadi.
GD-1
4
Complete outage of
220 kV HSR
substation
06-10-2015
at 16:32 hrs
All connected 220kV lines at
220kV HSR substation i.e.
Somanahalli, EPIP, Hoody and
Nagnathapura tripped during the
incident. Triggering incident was
fault in 220kV HSR-EPIP line
GD-1
Annexure-I
1 of 6
2. ग्रिडडडस्टर्बन्स / ग्रिडइन्सडन्टकावििरण - Details of Grid incidents:
Sr. No.
क्र.
सं.
घटनाकावििरण / Details
of Event
तारीख/ Date &
समय /Time कारण / Reason
टटप्पणी /Remarks
शे्रणी/ Category
1 Tripping of 400kV
Hassan-Udupi line-2
21-08-2015
at 23:48 hrs,
04-09-2015
at 21:42 hrs,
06-09-2015
at 1:59 hrs,
04-09-2015
at 21:42 hrs,
06-09-2015
at 1:59 hrs,
08-09-15 at
20:35 hrs
400 KV Hassan-Udupi line-2
tripped on receipt of DT from
UPCL end. DR and EL of Hassan
end was not furnished
2
Tripping of 400kV
Neyveli TS-2 –
Pugalur line 25-08-2015
at 16:09 hrs Line got tripped on broken
conductor fault and direct trip was
received at Pugalur end
3 Tripping of HVDC
Bhadrawati pole-1 29-08-2015
at 15:17 hrs Pole-1 blocked due to failure of
PLC AD4301 communication link
4
Tripping of 400kV
Gajwel-Hyderabad
line 05-09-2015
at 08:09 hrs
line tripped at Hyderabad end on
operation of reactor WTI
protection and line was holding
from Gajwel
5
Tripping of 400kV
Nagarjunsagar-
Mahboobnagar line 07-09-2015
at 2:58 hrs
line tripped on operation of over-
voltage protection at
Mahboobnagar and direct trip
received at N’sagar station. DT
receive was observed in DR and
EL of N’sagar station. D.R/EL of
Mahboobnagar was not furnished
to validate the overvoltage
tripping
6
Tripping of
400/220kV
Alamathy ICT-1&2
07-09-2015
at 04:24hrs
Triggering incident was failure of
Y & B phase CT failure in 230kV
Korattur feeder
7
Tripping of 400kV
YTPS-BTPS line
and tripping of
400kV RTPS-YTPS
line
08-09-2015
at 15:58 hrs
400kV YTPS-BTPS line tripped
on zone-2 at BTPS and in Zone-1
at YTPS. 400kV YTPS-RTPS line
tripped at RTPS end on operation
of over-current protection
Annexure-I
2 of 6
Sr. No.
क्र.
सं.
घटनाकावििरण / Details
of Event
तारीख/ Date &
समय /Time कारण / Reason
टटप्पणी /Remarks
शे्रणी/ Category
8
Tripping of 220KV
Tandur -Sedam line
10.09.2015 at
16:35 hrs
Line did not trip at Tamdur end.
FIR, DR EL of Sedam end was
not furnished
9
Tripping of ICT-1&2 at CHITTOOR
15.09.2015 at
16:55 hrs
Tripped on the operation of
directional overcurrent relay
10
Tripping of 400kV
Gajwel-Hyderbad
line
17-09-2015
at 1:45 hrs
Y-phase to earth fault had
occurred in line. 360ms after
occurrence of fault, over-voltage
stg-1 got operated at Hyderabad
end which resulted in a 3 phase
trip and DT send to Gajwe
11
Tripping of ICT-
1&2 at Arasur
substation
22-09-2015
at 15:01 hrs
400/230kV ICT-1 tripped on
operation of winding temperature
and ICT-2 tripped 8 seconds after
tripping of ICT-1 on operation of
back up overcurrent protection
12
Tripping of 400 kV
Guttur-Hiryur line-1
23-09-2015
at 15:45 hrs
Tripped at Guttur end during PT
supply change over. Direct trip
was received at hiryur end.
Similar tripping had occurred at
11:08 hrs on 29-07-2015 and at
17:54 hrs on 18-05-2015.
13
Tripping of 400/220
kV ICT-2 AT VISAKHAPATNAM
24-09-2015
at 18:09 hrs
ICT-2 tripped due to operation od
busbar protection at 220kV VSS
station of APTRANSCO
14
Tripping of 400kV
Gajwel-Hyderabad
line
25-09-2015
at 23:18 hrs
B-phase to earth fault occurred in
line. Line auto-reclosed at gajwel
end and failed to reclose at
Hyderabad. As per FIR of
Hyderabad S/s, over-voltage Stg-1
protection got operated 383ms
after occurrence of fault in B-
phase.
15
Tripping of
400/220kV ICT-3 at
Neelamangala
27-09-2015
at 14:55 hrs
ICT-3 (Y-phase) got tripped on
operation of oil surge relay and it
was found that OSR got operated
due to moisture ingress
16
Tripping of 765kV
Kurnool-Thiruvelam
line-2
29-09-2015
at 12:57 hrs
line tripped on operation of REF
protection of line reactor at
Kurnool end and direct trip was
sent to Tiruvallum end. REF had
operated due to suspected mal-
operation of CT switching relays
Annexure-I
3 of 6
Sr. No.
क्र.
सं.
घटनाकावििरण / Details
of Event
तारीख/ Date &
समय /Time कारण / Reason
टटप्पणी /Remarks
शे्रणी/ Category
17 Tripping of 400 KV
Hassan -Udupi line1 5-10-2015 at 13:33
Line tripped due to B-E fault in
Z2. Main 1 relay tripped in
Z2.Three phase trip operated at
Hassan. Auto relose successful at
other end and line was charging
from other end. Then OV stage 1
picked up in Main2 relay and
operated in OV after the time
delay
3. Failure or non-operation of Auto reclose during transient fault
Sr. No.
Element Date & Time
Reason
1
Tripping of 400kV
Vijayawada-Nellore(AP) line-3
05-09-2015 at
14:43 hrs&06-09-
2015 at 15:01 hrs
line tripped on a B-phase to earth
fault. Line auto-reclosed at
Nellore(AP) end and failed to
reclose at Vijayawada
2
Tripping of 400kV
Ramagundam-Hyderabad line-
4
11-09-2015 at 2:26
hrs R phase to earth fault had
occurred in line and line auto-
reclosed at Ramagundam end and
failed to reclose at Hyderabad end
3
Tripping of 400kV Gooty-
Neelamangala line
15-09-2015 on
23:55 hrs
Line tripped on R-phase to earth
fault and successfully reclosed at
Gooty end and failed to reclose
from Neelamangala end. Main-2
distance protection gave a three
phase trip
4
Tripping of 220kV Gajwel-
Shankarapally line 20-09-2015 at 2:24
hrs line tripped at Gajwel end on R-
Phase to ground fault. Reason for
non-auto reclose could be
established as DR and EL of both
ends were not furnished
4
Tripping of 400kV Udumalpet-
Tirunelveli line-2
23-09-2015 at
14:27 hrs B-phase to earth fault had
occurred in line. Line did not
auto-reclose and got tripped as
over-voltage stage-2 got operated
250 ms after occurrence of fault.
Similar tripping had occurred on
28-07-2015 at 16:48 hrs
5
Tripping of 400kV
Nagapatinam-Trichy line
26-09-2015 at
15:14 hrs
Y phase to earth fault occurred in
line. Line auto-reclosed at Trichy
end and failed to reclose at
Nagapatinam.
6
Tripping of 400kV Satenapalli-
Srisailam line1
26-09-2015 at
16:45 hrs
R-phase to earth fault had
occurred in line. Line did not auto
reclose from both ends. Direct trip
receive was observed in both end
Annexure-I
4 of 6
DR’s.
7
Tripping of 400kV Kayathar-
Karaikudi line-2
26-09-2015 at
17:05hrs
R Ph -earth fault had occurred in
line Line auto reclosed at
Karaikudi end and failed to
reclose at Kayathar
8
Tripping of 400kV Kayathar-
Karaikudi line-2
28-09-2015 at
15:42hrs
Y Ph -earth fault had occurred in
line Line auto reclosed at
Karaikudi end and failed to
reclose at Kayathar
9
Tripping of 400kV Neyveli
TS-2 Exp – Pugalur line
29-09-2015 at
16:42 hrs on
R-phase to earth fault had
occurred in line. Dt was received
at Pugalur from Neyveli 130ms
after occurance of the fault. This
resulted in a 3 phase trip at
Pugalur end.
10
Tripping of 400 kV Kurnool-Srisailam line
03-10-2015 at
04:40 hrs on
Tripped at both ends on Y-Phase
to ground zone-1fault. Attempt for
auto-reclose could not be
established.
11
Tripping of SATTENAPALLI - SRISAILAM 2
05-10-2015 at
16:24 hrs
B-phase to earth fault occurred in
line. Line did not auto-reclose as
DT was received from Srisailam
end.
4. Lines tripping due to tripping at one end/PLCC mal-operation
Sr. No.
क्र.
सं.
घटनाकावििरण / Details
of Event
तारीख/ Date &
समय /Time कारण / Reason
टटप्पणी /Remarks
शे्रणी/ Category
1
Tripping of 400kV
Trivandrum-
Tirunelveli line-2
at 16:36 hrs
and 16:50hrs
on 07-09-
2015
line tripped at Tirunelveli on
receipt of DT and line was
holding from Trivandrum
2
Tripping of 400kV
Kalpaka-Khammam-
2
08.09.2015 at
15:37 hrs
Tripped at Kalpaka end only on
receipt of Direct trip from
Khammam
3
Tripping of 400kV
Chittoor-
Krishnapatnam-II
08.09.2015 at
09:04 hrs
Tripped at Chittoor end on receipt
of direct trip from Krishnapatnam
4
400kV VTPS-
Malkaram line-1
10-09-2015
at 11:27 hrs
line tripped on DT receive at
Malkaram end and was holding
from VTPS
5
Tripping of 400kV
Guttur-Hiryur line-2
10:33 hrs on
18-09-2015,
9:40hrs on
19-09-2015,
13:53 hrs on
22-09-2015,
at 10:12hrs
on 30-09-
2015, 02:05
on 01-10-
line tripped at Guttur end only on
direct trip receive and was holding
from Hiryur.
Annexure-I
5 of 6
2015
6
Tripping of 400kV
Guttur-Narendra line
22-09-2015
at 13:53 hrs
line tripped at Guttur end only on
direct trip receive and was holding
from Narendra
7
Tripping of 400kV
Nellore-Thiruvelam
line-1
24-09-2015
at 10:52 hrs
line tripped at Thiruvelam end on
direct trip receive and was holding
from Nellore end.
8
Tripping of 400kV
Warangal-
Khammam line
29-09-2015
at 17:06 hrs
line tripped at Warangal end only
due to receipt of direct trip and
line was holding from Khammam
*****
Annexure-I
6 of 6
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Annexure-II
Page 20 of 20
Meeting
No /
Index
Details of
Event
Date Reason PCSC Recommendations Utility
Responsible
for
implementatio
n
Status of Recommendations
as on 06.10.2015
Remarks
45/II/14 Tripping of
400/220 kV
ICT-1&2 at
Gooty
substation
31-05-2015at
06:37 hrs
As per FIR, ICT-1&2 tripped on
operation of directional
overcurrent and earth fault
protection. It was reported that
there was fault in 220kV
APTRANSCO system
1. APTRANSCO to check resistive reach
of the distance relays on 220 kV Gooty
SS – Gooty RS line
2. APTRANSCO to check time
coordination of distance relay on Gooty
SS – Gooty RS line at Gooty SS with
Gooty ICT’s (1 & 2) back-up protection.
APTRANSCO Yet to be informed Pending
Pending Implementation of PCSC Recommendations (30th to 47th)
Andhra Pradesh
42/II/3 Outage at
Regulapadu
station of
APTRANSC
O
21-02-2015 at
00:49 hrs
Y-Ph Metering PT failed at
220KV
Ragulapadu Substation. Fault got
cleared
by tripping of lines from remote
ends.
APTRANSCO to furnish the remedial
measures taken in consequent to the
tripping
incident along with the status of bus bar
protection and bus coupler at Regulapadu
S/s.
A/R feature to be enabled on
Regulapadu – Alipuira 220 kV inter-state
line.
APTRANSCO Mail received on 27-05-2015:
1)Failed metering PT was replaced with new PT.
2) 220kV Ragulapadu is a single bus system. Hence there
is no provision for bus coupler at Ragulapadu SS.
Mail received on 24-06-2015:
APTRANSCO Vide Ltr. Dt. 23/06/2015, requested
KPTCL to furnish the details of available tele protection
equipments and details of the equipments going to be
procure for enabling the carrier aided protection on
220KV Ragulapadu-Alipura line. Based on the KPTCL
information we will take further necessary action.
Mail recieved on 22-08-2015:
APTRANSCOhas planned to commission ABB make
ETL-41 type PLCC terminal along with NSD-50 type
protection coupler at Ragulapadu end towards Alipura.
vide our Ltr Dt 23-07-2015, it is requested KPTCL to
arrange ABB make ETL-41 cabinet with NSD-50 type
protection coupler for establishing PLC communication
between Alipura- Ragulapadu.
Pending
ANNEXURE-III
Page 1 of 24
44/III/2 Tripping of
400kV
Ghanapur-
Mamidapalli
line
15-04-2015
at 2:03 hrs
Line tripped at Mamidapalli end
only and was holding at
Ghanapur. Overvoltage
protection had operated at
Mamidapalli
TSTRANSCO to make DR
functional at Mamidipalli
TSTRANSCO TSTRANSCO informed vide their mail dated 24.06.15
that the existing relays would be replaced with numerical
relays in DPR works.
Pending
Telangana
1. TSGENCO to disable sensitive earth
fault protection provided as
supplementary to static bus-bar
protection at Srisailam LB (GIS).
2. TSGENCO to set the current setting for
phase-to-ground faults for numerical bus-
bar protection at a
suitable value so that the prominent high-
resistance earth faults occurring within
the bus-zone are
covered at Srisailam LB (GIS).
400kV Srisailam-Mamidapalli
line-2, 400kV Srisailam-
Satenapalli line-2 and 400 kV
Srisailam-Kurnool line tripped
during multiple tripping at
Srisailam power station. 400kV
Srisailam-Mamidapalli-1 and
400kv Srisailam-Satenapalli-1
was kept out of service due over-
voltage conditions. There was no
generation at Srisailam left bank
power station. Triggering
incident was failure of CT in
400kV Srisailam- Satenapalli line-
2 at Srisailam end.
18-08-2015 at
15:25 hrs
Disturbance
in Srisailam
left bank
power station
47/I/1
(GD)
TSGENCO Yet to be informed Pending
ANNEXURE-III
Page 2 of 24
Yet to be informed Pending
Karnataka
30/I/A RTPS
Tripping
incidents and
the Spl
meeting held
at RTPS on
13th and
14th March
2014
Mar-14 Spl meeting held at RTPS on 13th
and 14th
March 2014
The PCSC forum recommended for
replacement of existing
electromechanical relays with
Numerical relays.
KPCL Mail recieved on 07-07-2015:
1. Retrofit of existing static relays with Numerical version
for lines M.nagar, M.bad and ICT- 1 & 2 -- Inspection of
the Numerical relays at M/s Siemens works completed
on 11-06-2015 and Dispatch clearance has been issued.
Materials received.
2. Retrofit of existing bus bar (CAG-34) with numerical
version – Budgetary offers obtained and is under process.
Mail recieved on 07-09-2015:
1. Replacement of Old electromagnetic relays with
Numerical relays has been completed for RTPS-BTPS
line & commissioned on 18.03.2014.
Raichur-PG1 & Raichur-PG2 lines have already
retrofitted with numerical relays.
The retrofitting of electromechanical relays with
Numerical version for ICT-1, ICT-2 and Munirabad line
has been completed.
Retrofitting work for Mehaboobnagar line is pending.
Awaiting for line shutdown.
2. Job order placed on 26.06.2015 on M/s Alstom T&D
India Ltd. Chennai for retrofitting of relays for all 220kV
lines at RTPS.
3. Retrofit of existing bus bar(CAG-34) with numerical
version– Budgetary offers obtained and is under process.
TSGENCO1. TSGENCO to check the reclaim time
of A/R and set it at 25 sec at KTPS.
2. TSGENCO to carry out PLCC end-to-
end testing in coordination with PGCIL
(SR-I) for KTPS – Khammam
line-2; retrofitting of Protection Coupler
may be carried out based on the test
results.
Y-phase to earth fault had
occurred in line. From Khammam
end DR it was observed that the
relay after dead time tried for
auto-reclose. The fault was
persisting and relay gave a single
phase
trip instead of a 3 phase trip after
1.25sec. R& B pole voltage dip
after 2 secpossibly due to
operation of pole discrepancy.
Auto-reclose close command
observed after 2.5 seconds
and all poles got closed.
30-07-2015 at
6:08 hrs
Tripping of
400kV
Khammam-
KTPS line-2
47/II/6
Pending
ANNEXURE-III
Page 3 of 24
30/I/A RTPS
Tripping
incidents and
the Spl
meeting held
at RTPS on
13th and
14th March
2014
Mar-14 Spl meeting held at RTPS on 13th
and 14th
March 2014
The PCSC forum recommended for
replacement of existing
electromechanical relays with
Numerical relays.
KPCL Mail recieved on 07-07-2015:
1. Retrofit of existing static relays with Numerical version
for lines M.nagar, M.bad and ICT- 1 & 2 -- Inspection of
the Numerical relays at M/s Siemens works completed
on 11-06-2015 and Dispatch clearance has been issued.
Materials received.
2. Retrofit of existing bus bar (CAG-34) with numerical
version – Budgetary offers obtained and is under process.
Mail recieved on 07-09-2015:
1. Replacement of Old electromagnetic relays with
Numerical relays has been completed for RTPS-BTPS
line & commissioned on 18.03.2014.
Raichur-PG1 & Raichur-PG2 lines have already
retrofitted with numerical relays.
The retrofitting of electromechanical relays with
Numerical version for ICT-1, ICT-2 and Munirabad line
has been completed.
Retrofitting work for Mehaboobnagar line is pending.
Awaiting for line shutdown.
2. Job order placed on 26.06.2015 on M/s Alstom T&D
India Ltd. Chennai for retrofitting of relays for all 220kV
lines at RTPS.
3. Retrofit of existing bus bar(CAG-34) with numerical
version– Budgetary offers obtained and is under process.
Pending
34/III/1 400kV
Raichur-
BTPS line
26-06-2014 Transient fault in R-phase.
Line did not auto reclose
A/R at BTPS end to be made
operational within one month
KPCL 1. A/R for 220kV lines enabled already.
2. Shut down of lines availed to commission the auto
reclosing schme for 400 kV line at BTPS.
Mail recieved on 28-05-2015:
P.O. placed for procurement of timers for A/R function.
Work shall be completed by July 2015.
Mail recieved on 07-07-2015:
P.O. placed for procurement of timers for A/R function.
Work shall be completed by August 2015.
Mail recieved on 07-09-2015:
P.O.placed for procurement of timersforA/R function.
Materials received at site. Work shallbecompleted by
December2015.
Pending
38/GD/3.
5
GD-1 at
Kadra and
Kodasalli
hydro power
station
13-11-2014 at
19:31hrs
A fault had occurred in 220 kV
Kadra and
Kodasalli. As A result, de-
energization of
220kV bus occurred at Kadra and
Kodasalli.
1. The PCSC forum requested KPCL to
speed up the installation of Numerical
Distance Protection relay in Kadra
–Kaiga and Kodasalli –Kaiga.
2. The PCSC forum requested KPCL to
submit the implementation status of
PSAG-10 recommendations within a
week’s time.
KPCL Mail recieved on 07-07-2015:
1. Cover -1 of the bid is scheduled for open eing on
25.06.2015.
2. As per the recommendations of PSAG, Relays were
temporarily rearranged. testing & commissioning
completed with the assistance of KPTCL.
Mail recieved on 07-09-2015:
NIT floated on 5.5.15 through e-portal. Bid evaluation
completed. Obtaining of Administration approval to place
P.O is in progress.
However, as per therecommendationsof PSAG-10, Relays
weretemporarilyrearranged.Testing & commissioning
completed with the assistanceofKPTCL.
Pending
ANNEXURE-III
Page 4 of 24
38/GD/3.
5
GD-1 at
Kadra and
Kodasalli
hydro power
station
13-11-2014 at
19:31hrs
A fault had occurred in 220 kV
Kadra and
Kodasalli. As A result, de-
energization of
220kV bus occurred at Kadra and
Kodasalli.
1. The PCSC forum requested KPCL to
speed up the installation of Numerical
Distance Protection relay in Kadra
–Kaiga and Kodasalli –Kaiga.
2. The PCSC forum requested KPCL to
submit the implementation status of
PSAG-10 recommendations within a
week’s time.
KPCL Mail recieved on 07-07-2015:
1. Cover -1 of the bid is scheduled for open eing on
25.06.2015.
2. As per the recommendations of PSAG, Relays were
temporarily rearranged. testing & commissioning
completed with the assistance of KPTCL.
Mail recieved on 07-09-2015:
NIT floated on 5.5.15 through e-portal. Bid evaluation
completed. Obtaining of Administration approval to place
P.O is in progress.
However, as per therecommendationsof PSAG-10, Relays
weretemporarilyrearranged.Testing & commissioning
completed with the assistanceofKPTCL.
Pending
Mail recieved on 27-05-2015 (KPTCL):
1. KPTCL has taken action to provide bus bar protection
to 220kV buses.
2. Over current relay Settings of ICTs to be reviewed by
PGCIL.
Mail received on 29-07-2015 (KPTCL):
Initial Tendering stage
Pending
38/GD/3.
1
GD-1 at
Mahalingapu
ra Substation
of KPTCL
25-10-2014 Fault had occurred in 220kV
Mahalingapura-Narendra line-2.
Due to the
failure of relay operation at
Mahalingapura,
breakers at remote end tripped
which
resulted in bus dead condition.
1. PCSC forum recommended KPTCL to
replace the old static distance
protection relays with numerical
relays.
2. PCSC forum also requested KPTCL to
provide a broken conductor alarm
indication in Control Room.
3. Standing instruction needed to be given
to the all substation personnel for not
changing the relay settings without
approval of RT/MRT wing.
KPTCL Mail received on 27-05-2015 (KPTCL) & 29-07-2015:
1.Existing Back up relays will be replaced by numerical
type distance relays.Procurement is in tendering stage.
Remaining observations were attended.
34/I/6 400/220 kV
ICT-1 & 2 at
MUNIRAB
AD
16-07-2014 As reported directional over
current relay of ICT’s operated
due to snapping of line jumper
in 220kV Lingapur line.
1. Bus bar protection shall be provided
by asset owner ( i.e KPTCL).
2. Settings for main distance protection
& Overcurrent protection shall be
examined and reviewed.
3. Time synchronization of the
Substation shall be ensured.
4. Correct DR shall be submitted to the
SRLDC for trip analysis.
KPTCL
Pending
ANNEXURE-III
Page 5 of 24
38/GD/3.
2
GD-1 at
Guttur
Substation of
KPTCL
05-11-2014 at
11:42 hrs
Circuit breaker of 400kV Guttur-
Hiriyur
line-1 failed at Guttur end while
availing
shutdown for replacement of
CVT. The
failure of breaker caused bus
fault at Guttur.
KPTCL was requested to expedite the
early implementation of pending
recommendations of:
1. Protection Audit (Phase-I & Phase-II)
2. PSAG-4, PSAG-5, and PSAG-8
KPTCL Mail received on 27-05-2015 & 29-07-2015:
Latest satus of implementatin of Phase-1 &2
recommendations, PSAG 4,5 and 8 is being obtained
from field. The Status will be updated witin a weeks time.
Pending
39/I/5 Tripping of
400/220kV
ICT-2 at
Hoody
substation of
KPTCL
01-12-2014 Suspected mal-operation of
220kV side Rphase
over current relay
1. PCSC forum recommended KPTCL to
replace the relay with a different make.
2. KPTCL was also requested to train the
O&M personnel adequately before
performing any maintenance works to
avoid such unwanted trippings.
KPTCL Mail received on 27-05-2015 & 29-07-2015:
C&R panels of 500MVA ICT 1&2 will be replaced
under scheduled R&M works. O&M personnel are
instructed to take sufficient care in order to avoid
unwarrented trippings.
Pending
40/I/1 GD-1 at
220kV
Ambewadi
Station of
KPTCL
22-12-2014 at
21:22 hrs
Triggering incident was B-phase
to earth fault in 220kV
Ambewadi- Nagzari line-1. B-
pole of breaker did not open at
Ambewadi end. LBB protection
not available at Ambewadi end.
All elements tripped on Zone-2
from remote ends.
1. Till the completion of R&M works for
bus bar and LBB protection, KPTCL shall
explore the possibility of having split
bus operation at Ambewadi and submit
the details of the same to PCSC forum.
2. KPTCL shall provide the details of the
tripping of Supa hydro station connected
downstream from 110 kV bus.
KPTCL Mail received on 28-04-2015:
1. In view of operating 220kV Ambewadi SS in split bus
mode, action is being taken up by KPTCL . Problem in
the 220kV bus coupler breaker is attended and isolator
overhauling work is under progress. Spilt bus
operation at Ambewadi will be made possible at the
earliest.
2. ICT protection system at Ambewadi and trippings
occured at Supa GS during the instance is checked up
and remedial measures already furnished in this regard.
Mail recieved on 29-07-2015:
Action is being taken by KPTCL for operating Ambewadi
in split bus mode. Problem in bus coupler breaker is
attended.Isolator overhaulling work is completed.PTs are
already provided to 220kV Bus-II. After commissioning
of Bus-II PTs, Ambewadi can be operated in split bus
mode. Pending works will be completed within a months
time.
Pending
ANNEXURE-III
Page 6 of 24
40/IV/1 220kV
Sedam-
Tandur line
20-12-2014
at 22:20 hrs
Line tripped on Yphase to earth
fault from both the ends
KPTCL was requested to explore the
possibility of providing A/R feature to
this line and submit the remedial
measures to the PCSC forum.
KPTCL Mail recieved on 29-07-2015:
Carrier protection is being restored for 220kV Sedam-
Tandoor line at Sedam end. After restoring the carrier
protection , AR will be enabled.
Pending
Mail received on 29-07-2015:
1. Procurement of Bus bar and LBB protection is in the
final tendering stage.
2. Action is being taken to restore the carrier protection
for 220kV Sedam-Tandoor line. AR will be enabled
after restoration of PLCC.
KPTCL 1. KPTCL to provide Bus bar and
LBB protections for 220 kV bus at
Sedam S/s.
2. KPTCL to implement A/R feature
on 220 kV Sedam-Tandur inter-state line.
R-Phase to ground fault occurred
on 220kV Sedam-Shahpur line.
Fault not cleared from Sedam end
due to stuck-breaker condition.
While the Sedam- Sahapur line
tripped from Shahapur end in
Zone-1, the other 220 kv lines
from Sedam tripped at remote
ends in Zone-2. This caused
complete outage of 220kV Sedam
substation.
27-01-2015 at
8.00 hrs
Complete
outage at
220kV
Sedam
Substation of
KPTCL (GD-
1)
41/I/4 Pending
41/I/1 GD-1 at
220kV Kadra
power
Station of
KPCL
16-02-2015 at
12:56 hrs
Triggering incident was B-phase
to earth fault had occurred in
220kV Kadra-Kodasalli line.
Line tripped from Kodasalli end
only. 220kV Kaiga-Kadra tripped
in Zone-3 from Kaiga end.
Tripping of evacuating lines
caused bus shut down at Kadra
hydro station.
1. KPCL to make functional the
Main2 (EPAC) relay with the help of
KPTCL at the earliest.
2. KPCL to investigate the reason for
DC fuse fail during transient fault in
220kV Kadra-Kodasalli line including the
testing/ checking of DC supply cables,
breaker control cables, and trip coils.
3. KPCL to ensure supply for Main-1&
Main-2 protections, Trip Coils (TC1,
TC2) from separate battery banks.
KPCL Mail received on 28-05-2015:
1. Main-2 relays already installed and commissioned.
2. DC fuses are intact. Till date no such incidence
occurred.
3. Possibility of DC-1 & DC-2 arrangement and splitting
of DC will be reviewed.
Mail received on 07-07-2015:
1. Completed.
2. Completed.
3. Possibility of DC-1 & DC-2 arrangement and splitting
of DC will be reviewed.
Pending
ANNEXURE-III
Page 7 of 24
42/I/1
(GD)
Complete
outage of
220kV
Sedam
substation of
KPTCL
15-02-2015 at
14:24 hrs
Fault occurred in 220kV Sedam-
Shahpur line
1. KPTCL to provide Bus Bar protection
and LBB protection at Sedam S/s and
furnish
the status of their implementation to
PCSC forum.
2. KPTCL to implement A/R feature on
220 kV Sedam-Tandur inter-state line.
KPTCL Mail received on 27-05-2015: 1. Bus Bar protection will
be provded under R&U.
2. A/R yet to be enabled.
Mail received on 29-07-2015:
1. Procurement of Bus bar and LBB protection is in the
final tendering stage.
2. Action is being taken to restore the carrier protection
for 220kV Sedam-Tandoor line. AR will be enabled after
restoration of PLCC.
Pending
42/I/2
(GD)
Complete
outage of
220kV
Ambewadi
substation of
KPTCL
12-03-2015 at
7:51 hrs
Fault in 220kV Ambewadi-
Nagjheri line-2
1. KPTCL shall provide A/R feature on
Ambewadi – Ponda 220 kV D/C inter-
state line.
2. Till the completion of R&M works for
bus bar and LBB protection, KPTCL shall
explore
the possibility of having split bus
operation at Ambewadi and submit the
details of the
same to PCSC forum.
KPTCL Mail received on 29-07-2015:
1. Procurement of Bus bar and LBB protection is in the
final tendering stage.
2. Action is being taken to restore the carrier protection
for 220kV Sedam-Tandoor line. AR will be enabled after
restoration of PLCC.
Pending
42/II/2 Tripping of
220kV
Chikodi-
Talandage
and
220kV
Chikodi-
Mudshingi
line
20-02-2015 at
06:40 hrs
Lines tripped during test charging
220kV
Chikodi-Belgaum line-2 from
Chikodi
end.
1. KPTCL to provide A/R feature on the
220 kV Chikkodi – Talandage, and 220
kV Chikkodi –Mudashinge inter-state
lines.
2. KPTCL to carry out E/F relay
coordination for Chikkodi - Talandage
and Chikkodi –
Mudashinge lines in coordination with
Maharashtra.
KPTCL Mail received on 27-05-2015:
Carrier protection is put in to service. AR will be enabled
at the earliest.
Mail received on 29-07-2015:
Action is taken for enabling AR for Mudashinge and
Talandage lines. Work is scheduled during first week of
August 2015.
Pending
43/II/14 Tripping of
400/220kV
ICT-1 at
BTPS
14-01-2015 at
1:09
hrs
ICT tripped due to operation of
Over current and Earth fault relay
KPCL to check the possibility of
providing line differential protection
between RTPS and Yermarus stations.
KPCL KPCL vide their mail dated 07.07.2015 informed that
revised relay settings would be incorporated in co-
ordination with KPTCL.
Mail received on 07-09-2015:
Revised relay settings are awaited from KPTCL.
Revised relay settings furnished by KPTCL will be
incorporated in co-ordination with KPTCL.
Pending
ANNEXURE-III
Page 8 of 24
45/III/12 Tripping of
400kV
Raichur-
BTPS line
01-06-2015 at
01:02 hrs
line tripped on R-phase to earth
fault. Line did not auto-reclose
KPCL to make A/R operational on 400
kV RTPS – BTPS S/C line at both ends.
KPCL Mail received on 07-09-2015:
PSL, Settings, Event & DR files have been sent to OEM
for checking & reviewing. Awaiting reply from OEM for
the same.
Pending
46/II/21 Trippings at
220kV
Raichur TPS
07-06-2015 at
01:35 hrs
1. KPCL to check the operation of anti-
pumping relay on 220 kV side and keep it
in healthy condition.
2. KPCL to provide manual reset to the
220 kV side master trip relay.
3. KPCL to use both the 220 kV buses as
main buses under normal operation, and
should go for single bus operation only
during emergencies.
KPCL Yet to be informed Pending
Mail received on 07.07.2015:
The matter had been discussed with KPTCL. KPTCL
recommended to keep Zone-2 time lever to zero. If this is
acceptable, then the same shall be incorporated
immediately.
Mail received on 07-09-2015:
The matter has been discussed with KPTCL. KPTCL
recommended to keep Zone-2 time lever to zero.
If this is acceptable to SRLDC, then the same shall be
incorporated immediately.Reply from SRLDC is awaited.
Pending44/II/3 Tripping of
220kV
Kaiga-
Kodasalli
and 220kV
Kodasalli-
Nagjheri line-
1
22-04-2015 at
20:28 hrs
220kV Kodasalli-Nagjheri line-1
tripped from Kodasalli end on
operation of
distance protection, zone-2.
220kV Kodasalli-Nagjheri line-
1&2 is kept opened from
Nagjheri end, hence fault
could not be cleared with carrier
aided protection. Backup earth
fault relay at
Kaiga end got operated during the
event and resulted in tripping of
220kV Kaiga-
Kodasalli line from Kaiga end.
1. KPCL to check the possibility of
implementing Permissive Over Reach
(POR) with Echo feature at Kodasally
end.
2. If the above is not possible, KPCL shall
check the possibility of keeping the
220kV
Kodasalli-Nagjheri lines OPEN at
Kodasalli end and idle-charged at
Nagjheri end, and
implement the same.
KPCL
KPTCL Mail receieved on 01-08-2015:
The problem is attended on 31.07.2015 and controls of
both the bays have been made independednt with effect
from 15.22Hrs.
KPCL1. KPCL to resolve the Lingapur line CB
Isolator problem without further delay.
2. Till the above issue is resolved, KPCL
shall use the said by-pass arrangement
only after revising the remote end
(Alipura and Lingapur) relay settings
suitably.Otherwise, the bypass isolator
and the Lingapur line CB shall be kept
open.
3. KPCL to furnish an action taken report
on these trippings to PCSC forum.
On 05-07-2015, ICT-1 tripped on
operation of 400kV side earth
fault and over current and Earth
fault relay. The reason for
tripping of ICT-1 on 06-07-2015
was not furnished in FIR
5-07-2015 at
20:56 hrs& 06-
07-2015 at 6:28
hrs
Tripping of
400/220kV
ICT-1 at
Bellary TPS
46/II/16 Pending
ANNEXURE-III
Page 9 of 24
47/III/8 Tripping of
220kV
Ambewadi-
Ponda line-2
02-08-2015
at 13:20 hrs
Line tripped on a transient fault
in B-phase. There is no
provision for auto reclose.
47/III/10 Tripping of
220kV
Ambewadi-
Ponda line-1
08-08-2015 at
10:51
hrs and 09-08-
2015 at
11:15 hrs
Line tripped on a B-phase to
earth fault. Line tripped as there
is no provision for auto-reclose
220kV RTPS-Lingasugur line-2
tripped at
TPS end on operation of distance
protection zone-1. 400/220kV
ICT-2 got
tripped on operation of earth fault
protection. 220kV RTPS-
Lingasugur line-
1&3 tripped on distance
protection
zone-2 and zone-3 respectively.
Due to
tripping of ICT-2, the running
units got
overloaded and it was mentioned
that
under frequency occurred as units
are
on load control. The Units got
tripped
on under frequency.
KPTCL to activate non-directional Over
Current protection with a time delay of
600-800 msec for Fuse
failure condition at Lingasugur.
KPTCL Yet to be informed Pending06-08-2015 at
4:51 hrs
Tripping of
Unit-1&2
along with
400/220kV
ICT-2 at
Raichur TPS
47/II/13
Till A/R is put into service on Ambewadi-
Ponda line-1, KPTCL to reduce Zone-2
time setting to zero sec. at Ambewadi
end.
KPTCL Yet to be informed Pending
ANNEXURE-III
Page 10 of 24
47/III/12 Tripping of
220kV
Ambewadi-
Ponda line-1
17-08-2015
at 13:20 hrs
Line tripped on a transient fault .
There is no provision for Auto
reclose.
45/II/12 Multiple
tripping at
400/230kV
Alamathy
substation
25-05-2015at
09:08hrs
As per FIR, failure of R-phase
CT of 230kV Alamathy-Manali
feeder occurred at Alamathy end.
Hence 230KV Bus bar protection
Zone 1 & 2 Operated at Alamathy
substation. All the 230KV
feeders, 230KV Bus Coupler,
ICT-3, 4 & 5 LV breakers got
tripped.
TANTRANSCO to furnish a detailed
tripping report including reasons for
delayed clearance of fault at Almathy.
TANTRANSC
O
TANTRANSCO's letter dtd 14-07-2015 received, but
reasons for the delayed clearance of the third fault not
furnished.
Mail received on 03-09-2015:
The faults were cleared with out time delay at Alamathy
SS. Detailed Tripping report sent vide
Lr.No.CE/P&C/SE/D/ EPC4/AEE3/F.SRPC/ D.21/15,
dated 14.07.2015.
The reasons for the delayed clearance of the third fault
not furnished.
Pending
KSEB Mail received on 31-07-2015:
1. Reducing the sensitivity of REF protection of Unit # 4,
5, 6 at Idukki PH: - Generation wing is planning to
purchase new transformer management relays with low
impedance REF protection. Purchase procedures initiated.
2. The replacement/ repair of faulty breakers are under the
consideration of Generation wing. Breakers will be
replaced / repaired in a phased manner. Unit #3 breaker
was replaced with available breaker from the 220kV
IDMD feeder. The 220kV CBs of unit #2 and unit #3 will
be replaced with in two months.
3. No abnormalities were noticed in the PLCC equipment
at New Pallom station. It is kept under observation.
Till A/R is put into service on Ambewadi-
Ponda line-1, KPTCL to reduce Zone-2
time setting to zero sec. at Ambewadi
end.
KPTCL Yet to be informed Pending
Tamil Nadu
Kerala
Line-2 tripped on R-phase to
earth fault.
Line autoreclosed at SVChatram
end and failed to reclose at
Alamathy end. Bphase to earth
fault in line-1. Line tried for A/r
but due to permanent fault line
did not reclose. ICT tripped on
operation of over flux protection.
TANTRANSCO was requested to swap
the relays between two stations, so that
Main-1 and Main-2 will be of different
make at each station.
TANTRANSC
O
TANTRANSCO vide their mail dated 24.06.15 informed
that different relays in Main-I & Main-II would be
ensured at the earliest.
Mail recieved on 24-07-2015:
Different relays in Main-I & Main-II will be ensured.
Pending29-03-2015 at
15:29 hrs
43/II/5 Tripping of
400kV
Alamathy-
SVChatram
line-1&2
and
400/230kV
ICT
at
S.V.Chatram
Pending44/I/1
(GD)
Complete
outage of
Idukki Hydro
Power
Station (GD-
1)
28-04-2015 at
12:30 Hrs
220 kV breaker of unit-3 at
Idukki Power
house flashed and bus differential
protection
acted. All Generators (6Nos.)
along with all
220 kV feeders tripped during the
incident.
1. KSEB to reduce sensitivity of REF
protection appropriately at Idukki PH.
2. KSEB to replace/ repair the faulty
breaker.
3. KSEB to check the PLCC equipment at
New Pallam and inform the remedial
measures taken to PCSC forum.
ANNEXURE-III
Page 11 of 24
44/I/2
(GD)
Disturbance
in North
Kerala
system (GD-
1)
09-05-2015 at
11:18hrs
Blackout had occurred in North
kerala i.e.,
Complete outage of 220kV
Mylatty, 220kV
Taliparamba, 220kV Kanhirode,
220kV Vadakara and Shoranur
substations occurred due
to tripping of 220kV Thrissur-
Areacode and
220kV Thrissur-Shoranur
feeders.
1. KSEB to replace Quadramo relay
(static) with numerical one at
Madakkathara station.
2. After finalizing the SPS, KSEB shall
share the details of the revised SPS logic
for the
North Kerala system to PCSC forum.
KSEB Mail received on 31-07-2015:
1. All quadramo relays in Madakkathara is working in
good condition. Replacement of the same with numerical
one will be carried out in a phased manner.
2. The SPS settings were revised after this disturbance
and the revised logic is already forwarded to that office
vide reference (2) above. Copy of the same is attached
Pending
41/III/2 Tripping of
400kV
Udumalpet-
Palakad line-
1& 400
Udumalpet-
Arasur line-2
09-02-2015 at
9:50hrs
PLCC of Udumalpet-Arasur-2
mal-operated
• PGCIL to furnish remedial measures
taken.
• PGCIL to properly tune PLCC panels.
PGCIL Mail received on 02-09-2015:
The issue was referred to BPL and OEM suggested to
upgrade the panels with design modifications. LOA has
been placed on BPL for the same. Work is expected to be
completed by Aug'15 end.
Pending
KSEB Mail received on 31-07-2015:
1. Reducing the sensitivity of REF protection of Unit # 4,
5, 6 at Idukki PH: - Generation wing is planning to
purchase new transformer management relays with low
impedance REF protection. Purchase procedures initiated.
2. The replacement/ repair of faulty breakers are under the
consideration of Generation wing. Breakers will be
replaced / repaired in a phased manner. Unit #3 breaker
was replaced with available breaker from the 220kV
IDMD feeder. The 220kV CBs of unit #2 and unit #3 will
be replaced with in two months.
3. No abnormalities were noticed in the PLCC equipment
at New Pallom station. It is kept under observation.
PGCIL34/I/7 HVDC
BHADRAV
ATHI POLE
2
18-07-2014 As reported pole-2 tripped due
on 5th harmonic alarm.
1. Complete analysis of the faults and
rectification/remedial action taken to
avert similar occurrence in the HVDC
Back to Back station shall be submitted.
2. The PCSC forum recommended
PGCIL, SRTS-I take up the issue with
WRTS to submit the report as per IEGC
guidelines.
3. SRLDC is also requested to send a
letter to WRLDC to submit the reports to
SR also.
4. Based on the SRTS/SRLDC
correspondences, SRPC would take it up
with WR and PGCIL if the issue is not
getting resolved.
PGCIL Reply received during 46th PCSC meeting:
Being pursued with POWERGRID, WR-1
Pending44/I/1
(GD)
Complete
outage of
Idukki Hydro
Power
Station (GD-
1)
28-04-2015 at
12:30 Hrs
220 kV breaker of unit-3 at
Idukki Power
house flashed and bus differential
protection
acted. All Generators (6Nos.)
along with all
220 kV feeders tripped during the
incident.
1. KSEB to reduce sensitivity of REF
protection appropriately at Idukki PH.
2. KSEB to replace/ repair the faulty
breaker.
3. KSEB to check the PLCC equipment at
New Pallam and inform the remedial
measures taken to PCSC forum.
Pending
ANNEXURE-III
Page 12 of 24
42/II/7 Tripping of
400kV
Jeypore-
Gazuwaka
line-
1&2 and
tripping of
HVDC back
to back pole-
1&2 at
Gazuwaka
23-02-2015 at
13:34 hrs
HVDC pole-1 got tripped due to
failure
of 4 no. power supply card.
HVDC
pole-2 tripped on DC low voltage
trip.
400kV Jeypore-Gazuwaka line-
1&2
tripped due to operation of Over
voltage
protection at Gazuwaka end.
PGCIL (SR-II) to submit the report of
M/s ABB’s on preventing supply card
failures.
PGCIL Yet to be informed Pending
42/II/22 Tripping of
HVDC pole-
1&2
at Gazuwaka
and
400kV
400kV
Jeypore
Gajuwaka
line -1
14-03-2015 at
17:12 hrs
HVDC Pole-1 at Gazuwaka
tripped due to
tripping of filter banks and Pole-
2 tripped
due to operation of differential
protection.
400kV Jeypore-Gazuwaka line-1
tripped
on over-voltage from Gazuwaka
end.
PGCIL (SR-I) to furnish the reasons for
Converter Transformer differential
protection
operation for Pole-2 along with the
remedial measures taken.
PGCIL Reply received during 46th PCSC meeting:
Operation is in-order as per OEM manual (ABB HVDC)
Pending
42/II/23 Tripping of
HVDC
Bhadravathi
Pole-1
18-03-2015 at
13:55 hrs
Pole tripped due to failure of
auxiliary supply
PGCIL (SR-I) to submit the compliance
report on PSAG-11 recommendations to
PCSC
forum.
PGCIL Reply received during 46th PCSC meeting:
Tertiary Transformer charged and auxiliary power for
HVDC is being availed from tertiary widings of ICT.
Pending
43/II/2 Multiple
tripping
at 400/230kV
Hosur
substation
of Powergrid
26-03-2015
at 15:40 hrs
230kV Bus-2 at Hosur (PG) got
tripped as spurious initiation got
extended to LBB relay of 230kV
Hosur-Hosur(PG) line at
Hosur(PG)
end due to shorting of contacts in
lockout relay. 400/230kV ICT-2,
ICT-
3, 230kV Hosur-
Vinnamangalam,
230kV Hosur(PG)-Hosur which
were
connected to Bus-2 got tripped
along
with bus coupler breaker
PGCIL (SR-II) to check the possibility of
providing re-trip feature in LBB relay.
PGCIL Mail received on 02-09-2015:
The scheme was tested thoroughly found normal.
Pending
ANNEXURE-III
Page 13 of 24
44/I/3
(GD)
765 kV
Raichur-
Sholapur line
1 &
2 tripped
24-05-2015
at 19:19 hrs
Tripped on Overload. 1. PGCIL to provide the status of
healthiness of SPS contact logic in
SRLDC’s SCADA.
2. PGCIL to furnish the details of the
implemented SPS-7 scheme including
logic diagram to PCSC forum.
PGCIL Yet to be informed Pending
44/II/6 Multiple
tripping at
Vemagiri
substation of
APTRANSC
O
25-04-2015 at
10:04
hrs
400kV Vemagiri-Vijayawada line-
1&3, 400kV Vemagiri-Goutami
line-2, 400kV Vemagiri-
Konaseema line-2 and
400/220kV ICT-2 at Vemagiri
tripped during the incident.
Triggering incident
was failure of B-phase L.A in
400kV Vijayawada-Vemagiri line-
1 at Vemagiri end.
1. PGCIL (SR-I) to enable Auto reclosure
feature at Vijayawada end.
2. PGCIL (SR-I) to check distance relay
settings for Vijayawada – Vemagiri line
3, and
furnish a compliance report to PCSC
forum.
PGCIL Yet to be informed Pending
PGCIL (SR-I) to check healthiness of
PLCC panels at Hyderabad SS, and
repair/ replace
them, if necessary.
400kV Ramagundam-Hyderabad
line-3 at
ramagundam end only due to DT
receive.
400kV Hyderabad-Malkaram line-
1
tripped at Hyderbad end only and
was holding from Malkaram end.
400kV Bus-1 at Hyderabad due
to operation of bus bar protection.
23-04-2015 at
15:11 hrs
Tripping of
400kV
Ramagunda
m-Hyderabad
line-3,
400kV
Hyderabad-
Malkaram
line-1 and
400kV Bus-1
at Hyderabad
44/II/4 PendingYet to be informedPGCIL
ANNEXURE-III
Page 14 of 24
44/II/7 Tripping of
765kV
Kurnool-
Tiruvalam
line-1
and 765kV
Kurnool-
NPS-1
25-04-2015 at
18:10 hrs
REF protection of Line reactor of
Nellore-1&2 and Tiruvalam line-
1 maloperated
due to DC earth fault
1. PGCIL (SR-I) to submit the action
taken report on the measures suggested by
their OEM.
2. PGCIL (SR-I) to check for the
availability of Chatter Disable feature in
P141 and
configure it appropriately to block
operation of REF protection on DC
fluctuations.
PGCIL Yet to be informed Pending
44/II/8 Tripping of
400kV
Gooty-NPS
line-2
26-04-2015 at
13:16
hrs
R-phase to earth fault had
occurred in
line. Lines auto-reclosed at gooty
end
and later tripped due to DT
receive from
NPS end.
PGCIL (SR-I) to coordinate STUB
protection settings with the distance
protection time
settings at NPS.
PGCIL Yet to be informed Pending
45/II/21 Tripping of
400/220kV
ICT-1 at
Gooty
Substation
03-06-2015 at
12:30 hrs
ICT tripped due to mal-operation
of differential relay
1. PGCIL to follow IS and CEA
regulations while carrying out
maintenance work.
2. PGCIL to furnish a report on what
caused the ICT-1 tripping including
remedial measures.
PGCIL Yet to be informed Pending
To avoid tripping of transmission lines on
transient faults, PGCIL is recommended
to carry out periodic patrolling of lines,
and ensure their proper maintenance by
carrying out jungle/ bushing clearance
and trimming of tree branches within the
RoW of transmission lines as per the
SRPC transmission line patrolling
guidelines (available under the menu item
"All Uploads Operation
Miscellaneous Transmission Line
Patrolling Protocol / Guidelines for
Southern Region" on SRPC website).
PendingYet to be informedPGCIL45/II/15 Tripping of
765kV
Raichur-
Solapur line-
1&2
03-05-2015 at
4:13 hrs
Lines tripped on transient fault.
Auto reclose was un-successful.
SR &NEW grid separated due to
tripping of 765kV lines
ANNEXURE-III
Page 15 of 24
46/II/1 Tripping of
400/220kV
ICT-2 at
Nagarjunsaga
r Station
16-06-2015 at
18:12 hrs&
19:18 hrs
ICT-2 tripped due to mal-
operation of 86B relay due to
suspected DC earth fault.
PGCIL (SR-I) to furnish a detailed
report on ICT-2& Bus II outage at 19.18
hrs on 16.06.2015 along with the
remedial measures taken.
PGCIL Yet to be informed Pending
46/II/4 Tripping of
400/220kV
ICT-2 at
Gooty
substation
22-06-2015 at
13:06 hrs
At 220kV Gooty Switching
Station, 220KV Gooty Receiving
Station feeder line side Y-Phase
jumper connected between line
isolator to boom resulting in a
220kV Bus fault. This resulted in
tripping of ICT-2 and 220kV
feeders connected to 220KV BUS-
II
PGCIL (SR-I) to furnish a detailed
report as to what caused LBB operation at
400 kV Gooty SS along with the remedial
measures taken.
PGCIL Yet to be informed Pending
46/II/13 Tripping of
400kV Gooty-
NPS line-1
01-07-2015 at
09:59 hrs
Breaker at NPS end tripped on
Direct Trip receipt from NPS
end. After 4 seconds, over voltage
protection operated at NPS end as
observed from EL, and direct trip
was sent to Gooty.
PendingYet to be informedPGCIL1. PGCIL (SR-I) to furnish a report
detailing the sequence of events including
the remedial measures taken to PCSC
forum.
2. PGCIL (SR-I) to verify and ensure
time-synchronizationof DR& EL with
GPS at both Gooty and NPS.
3. PGCIL (SR-I) to check and resolve,in
co-ordination with APTRANSCO, the
professed Phase-Discrepancy that is
found to be occurring between 400 kV
Gooty (PG) SS and the surrounding 220
kV network of APTRANSCO in the
event of a fault.
45/II/29 Tripping of
HVDC
Talcher-
Kolar Pole-2.
26-05-2015 at
17.55 hrs
DC line fault PendingYet to be informedPGCILTo avoid tripping due to transient faults,
PGCIL (SR-I) is recommended to carry
out periodic patrolling of lines, and
ensure proper maintenance of
transmission lines by carrying out jungle/
bushing clearance and trimming of tree
branches within the RoW of transmission
lines as per the ‘SRPC transmission line
patrolling guidelines’ (available under the
menu item "All Uploads Operation
Miscellaneous Transmission Line
Patrolling Protocol / Guidelines for
Southern Region" on SRPC website).
ANNEXURE-III
Page 16 of 24
47/II/11 Tripping of
HVDC
Bhadrawati
Pole-1
05-08-2015 at
10:53 hrs
Main pump-2 of valve cooling
got
tripped during dip in 33kV
auxiliary bus
voltage. Valve cooling flow got
reduced
due to tripping of pump and
resulting in
tripping of pole-1
PGCIL (SR-I) to furnish compliance
report on PSAG-11 recommendations
without further delay to PCSC
forum.
PGCIL Yet to be informed Pending
765 kV
RAICHUR -
SHOLAPUR
1 and 2
04-09-2015 at
19:25 hrs
Sholapur -1 and 2 Feeder got
tripped at
Raichur end on operation of over
current
protection in Main-1 distance
relay and
holding from Solapur end on
04.09.2015 at
19:24:42 Hrs
46/II/13 Tripping of
400kV Gooty-
NPS line-1
01-07-2015 at
09:59 hrs
Breaker at NPS end tripped on
Direct Trip receipt from NPS
end. After 4 seconds, over voltage
protection operated at NPS end as
observed from EL, and direct trip
was sent to Gooty.
PendingYet to be informedPGCIL1. PGCIL (SR-I) to furnish a report
detailing the sequence of events including
the remedial measures taken to PCSC
forum.
2. PGCIL (SR-I) to verify and ensure
time-synchronizationof DR& EL with
GPS at both Gooty and NPS.
3. PGCIL (SR-I) to check and resolve,in
co-ordination with APTRANSCO, the
professed Phase-Discrepancy that is
found to be occurring between 400 kV
Gooty (PG) SS and the surrounding 220
kV network of APTRANSCO in the
event of a fault.
46/II/22 Separation of
SR-grid and
NEW-grid
28-07-2015 at
11.52.22 hrs.
PendingYet to be informedPGCIL1. PGCIL (SR-I) to obtain from PGCIL
(WR-l) the reasons for DT receipt from
Sholapur end and furnish thesame along
with the remedial measures taken to
PCSC forum.
2. PGClL (SR-I) to verify the logic
implemented of SPS-1 and SPS-7 for the
76S kV Raichur - Sholapur link
byavailing the line shutdown at the
earliest opportune time.
3. PGCIL (SR-I) to furnishthe details of
the implemented SPS-1 and SPS-7
schemes including their logicdiagrams to
PCSC forum.
47/II/18 1. PGCIL (SR-I) to check the A/R scheme
implemented through BCU’s at all its
GIS/ SAS substations for correct
operation.
2. PGCIL (SR-I) to ensure time-
synchronization of DR & EL of 765 kV
Kurnool SS with GPS.
3. PGCIL (SR-I) to sort out the LEGEND
ISSUE related to tripping of the lines in
the Event Logger of Raichur.
4. PGCIL (SR-I) to check & ensure the
functionality & healthiness of
synchronization facility at Raichur end at
the earliest opportune time.
PGCIL Yet to be informed Pending
ANNEXURE-III
Page 17 of 24
765 KV
RAICHUR –
KURNOOL
2
04-09-2015 at
19:25 hrs
Kurnool -II Feeder got tripped on
B-N fault
and holding from Kurnool end
(successfully
auto-reclosed at Kurnool end)
subsequently
tripped at other end on operation
of Over
Voltage stg-1 protection at
Raichur end on
04.09.2015 at 19:24 Hrs
47/IV/1 Tripping of
400kV
Kayathar-
Karaikudi
line-
2
26-07-2015
at 23:03 hrs
Line tripped on operation of
overvoltage protection at
Karaikudi end. However voltage
was continuously observed in
D.R of Karaikudi station.
PGCIL (SR-II) to adopt SRPC provided
voltage grading for OVR, Stage-I
operation for the 400 kV lines emanating
from Karaikudi.
PGCIL Yet to be informed Pending
41/II/10 Tripping of
Hassan-
UPCL line-2
12-02-2015 at
15:57 hrs
Line tripped due to high
resistance fault in B-phase. DEF
picked up at hassan end and DT
was sent to UPCL. DEF
protection did not pick up at
UPCL
UPCL to revise their DEF relay
settings.
UPCL Mail recieved on 28-04-2015: Revised settings
issued to UPCL on 27-04-2015 for implementation.
Mail received on 27-05-2015: Revised settings have to
be implemented by UPCL
Pending with
UPCL
47/II/18 1. PGCIL (SR-I) to check the A/R scheme
implemented through BCU’s at all its
GIS/ SAS substations for correct
operation.
2. PGCIL (SR-I) to ensure time-
synchronization of DR & EL of 765 kV
Kurnool SS with GPS.
3. PGCIL (SR-I) to sort out the LEGEND
ISSUE related to tripping of the lines in
the Event Logger of Raichur.
4. PGCIL (SR-I) to check & ensure the
functionality & healthiness of
synchronization facility at Raichur end at
the earliest opportune time.
PGCIL Yet to be informed Pending
Others37/I/9 Tripping of
400/220kV
ICT-1&2 at
UPCL
04-10-2014 ICT-1&2 tripped during transient
fault in R-phase in 400kV Hassan-
UPCL line-1
To avoid tripping of ICTs for line fault,
UPCL is requested to review the settings
of ICT’s SEF relay and consider IDMT
setting instead of existing Definite Time
setting.
UPCL It has been reported by UPCL that, the work of review of
relay coordination and setings for the entire plant is given
to M//s Alstom for entire plant. UPCL has furnished the
settings given by M/s Alstom for verification. Revised
settings will be issued this week for implementation
Mail recieved on 28-04-2015: Revised settings
issued to UPCL on 27-04-2015 for implementation.
Mail received on 27-05-2015: Revised settings have to
be implemented by UPCL
Pending with
UPCL
ANNEXURE-III
Page 18 of 24
41/II/12 Tripping of
400KV
Coastal-
NTPL line
13-02-2015 at
22:54 hrs
Line tripped B-phase to earth
fault and later tripped on R-Y
phase fault. From Coastal end
D.R, Y & B poles of breaker
opened first and R-pole appears
to be opened on Pole discrepancy.
CEPL to check A/R scheme at their
end.
CEPL Yet to be informed Pending
41/IV/2 400kV
Tuticorin PS-
NTPL line
09-02-2015 at
03:17 hrs
Y-phase to earth fault had
occurred in line. Line auto
reclosed at Tuticorin PS end and
failed to reclose at NTPL end.
NTPL to check A/R scheme at their end. NTPL Yet to be informed Pending
44/III/4 Tripping of
400kV
Coastal
(CEPL)-
Tuticorin
pooling
station
20-04-2015
at 12:35 hrs
Line tripped at Coastal energen
end only and was holding from
TTRNPS
CEPL to furnish a detailed report on this
trip event to PCSC forum.
CEPL Yet to be informed Pending
44/IV/8 Tripping of
400kV
Hassan-
UPCL line-2
06-05-2015 at
15:37 hrs
Y-phase to earth fault in line.
Line auto reclosed at
Hassan end and did not reclose at
UPCL
UPCL to check A/R relay operation at
their end.
UPCL Yet to be informed Pending
46/II/3 Tripping of
400kV
Ramagunda
m-Dichipalli
line
21-06-2015 at
03:27 hrs
Line tripped on operation of
overvoltage protection at
Ramagundam end and direct trip
was received at Dichipalli. Over-
voltage operation could not be
established with D.R & E.L
submitted by Ramagundam
station.
1. NTPC, Ramagundam to investigate
the reasons for Over Voltage alongside
checking the drop off- to- pick-up ratio of
the OV relay.
2. The tripping is not as per the grading
adopted for Overvoltage, Stage-I
protection (Grading is C2: 110% and 6
sec time delay) at Ramagundam. NTPC,
Ramagundam to check up the same.
NTPC Yet to be informed Pending
ANNEXURE-III
Page 19 of 24
47/III/2 Tripping of
400kV
Vemagiri –
GVK (JPD)
line-2
16-07-2015
at 17:02 hrs
R-phase to earth fault had
occurred in line. Line auto
reclosed at Vemagiri end and
failed to reclose at GVK end.
GVK to put A/R into service at GVK
Jegurupadu end on 400 kV GVK
(Jegurupadu) – Vemagiri line-2.
GVK Yet to be informed Pending
36/II/8 400kV
Raichur-
Munirabad
line
07-09-2014 B-phase to earth fault had
occurred in line.
Line auto reclosed at Munirabad
end and failed to reclose at
Raichur end.
KPTCL:
PD (pole discrepancy) time delay would
be changed.
PGCIL /
KPTCL
Yet to be informed Pending
38/II/5 400kV
Ramagunda
m-
Hyderabad
line-4
27-10-2014 Line tripped on Bphase
to earth fault.
Line did not auto
reclose at Hyderabad
end due to
PLCCmal-operation.
Planned to replace the PLCC system
within a week's time at both the ends
during the shutdown.
NTPC/ PGCIL Yet to be informed. Pending
Miscellaneous
37/I/6 Tripping of
400KV
Hassan-
UPCL line-2
25-09-2014 High resistance fault as the fault
ampere was very less i.e., 0.6kA
at Hassan end and nearly 0.9kA
at UPCL end.
Back up earth fault protection
had operated at Hassan.
At UPCL end the high resistance
fault got converted into a R ph-B-
ph fault which resulted in
operation of distance protection
Zone-1.
The reason for non-picking up of
Back up earth fault at UPCL
needs investigation.
1. At UPCL end, unused zones of
distance protection (probably zone 5 to
8) shall be disabled.
2. At UPCL end, time synchronization
between main-1 and main-2 relays shall
be ensured.
3. UPCL shall ensure time
synchronization with Hassan
substation.
4. Reasons for non operation of back
up protection at UPCL for high
resistance fault is to be submitted.
5. Reasons for not sending DT to
UPCL by Hassan end is to be submitted.
6. Settings of UPCL are to be reviewed
and informed to PCSC forum.
UPCL /
KPTCL
It has been reported by UPCL that, the work of review of
relay coordination and setings for the entire plant is given
to M//s Alstom for entire plant. UPCL has furnished the
settings given by M/s Alstom for verification. Revised
settings will be issued this week for implementation.
Mail recieved on 28-04-2015:
Revised settings issued to UPCL on 27-04-2015 for
implementation.
Mail received on 27-05-2015 (KPTCL):
Revised settings have to be implemented by UPCL
Pending with
UPCL.
ANNEXURE-III
Page 20 of 24
40/II/3 Tripping of
400
kV
TALAGUPP
A
– HASSAN
line
01-01-2015 at
13:38 hrs
On account of R-phase to earth
fault, line
tripped at Hassan end due to
operation of
distance Zone-2 and non-receipt
of
carrier. From D.R of Talaguppa
end it is
observed that fault had occurred
in Yphase.
1. PGCIL and KPTCL to ascertain the
reason for the phase discrepancy in the
relay operation and take suitable
remedial measures.
2. KPTCL to check the PLCC operation
at Talaguppa end and submit the report
to the PCSC forum.
PGCIL/
KPTCL
Mail received on 27-05-2015 (KPTCL) & 29-07-2015:
End to end testing of PLCC has been done and problem in
the PLCC is atttended.
Phase discripancy in the relay operation is to be
checked jointly.
Mail recieved on 02-09-2015:
Problem is in identification of phases at Talguppa end. To
be rectified by M/s KPTCL.
Pending
41/I/2 Complete
outage at
220kV
Bahoor
Substation of
Pondicherry
(GD-1)
15-02-2015 at
11:20 hrs
Bus fault occurred in 110kV bus
at 230/110kV Bahoor substation
due to failure of Y-phase main
bus strain insulator. 220kV lines
connected to Bahoor (viz.,
Bahoor- NLC TPS II and Bahoor
– Pondy) tripped from remote
end on operation of back up
protection.
1. PED to investigate the cause of non-
operation of ICT’s protection system
(differential protection, back-up
protection) and review the relay settings
suitably.
2. PGCIL to check the settings of
distance relay and back-up relays for
correctness of operation.
PED/PGCIL Mail received on 02-09-2015:
All the relay settings were checked and found ok
Pending
42/II/1 Tripping of
400kV
Coastal-
Tuticorin PS
line
19-02-2015 at
16:37 hrs
Line tripped at Coastal end only
due to suspected PLCC
maloperation
and was holding from
Tuticorin PS end. Running Unit
at
Coastal energen also got tripped
during the event.
PLCC end-to-end testing shall be carried
out by CEPL and Tuticorin PS (PGCIL-
SR II) by
06.04.2015.
CEPL/
PGCIL(SR-II)
Mail received on 02-09-2015:
On 11.06.2015 PLCC testing carried out by M/s ABB
Engineer. ABB suspects that the problem is with
frequency interference related issue, and suggested to
change to new frequecies.
Pending
39/I/2 Tripping of
400Kv
Ghanapur-
Mamidipally
line
22-12-14
at 10:52 hrs,
24-12-14 at
11:32
hrs,
24-12-14 at
16:16 hrs
Due to PLCC Mal-operation at
HYD S/S end, DT received at
MMPLY end and line got
tripped.
PGCIL is requested check up with the
manufacturer to resolve the issue and
submit remedial measures to PCSC
forum.
PGCIL/
TSTRANSCO
Mail received on 26-05-2015 from TSTRANSCO:
On 27-12-2014 PGCIL requested to arrange services of
OEM(Manufacturer)for identifying the problem.
TSTRANSCO arranged the same on 06-01-2015 and the
manufacturer testing and concluded that the problem in
not in the newly erected digital protection coupler at both
ends and the issue is related to relay panel at Ghanapur.
[OEM minutes enclosed]
Pending
ANNEXURE-III
Page 21 of 24
43/II/12 Multiple
tripping at
400kV
Raichur(PG)
and Raichur
thermal
power station
of
KPCL
11-04-2015at
18:04 hrs
400kV Raichur(PG)-Gooty line-
2,
400kV Raichur TPS-
Raichur(PG)
line-1&2, 400kV Raichur-
Mahboobnagar, Unit#5 at RTPS
tripped during the incident
KPCL, KPTCL and PGCIL (SR-I) to
furnish the action taken report on the
recommendations given by PSAG
members held at Raichur on 22-04-2015
and
23-04-2015.
KPCL/KPTCL/
PGCIL(SR-I)
Yet to be informed Pending
Tripping of
Unit 1 at
NCTPS
24-05-2015
at 19:13 hrs
ID Fan trip
Tripping of
Unit 1 at
MEPL
24-05-2015
at 19:13 hrs
Coal Mill tripped
Tripping of
Unit 1 at
Krishnapatna
m
24-05-2015
at 19:17 hrs
Generator Protection operated
Mail received on 26-05-2015 from TSTRANSCO:
It is found that the main-2 ABB make REL316 type
distance relay was defective and same was replaced with
MICOM P444 by M/s.PGCIL on 23.04-2015. After
replacement of main-II, DR can be extracted from this
relay. For EL in to service, some field winding is pending
which is being taken up in this month.
Pending
44/I/3
(GD)
1. All Tripped units, viz.,
Krishnapatinam, MEPL, Raichur,
NCTPS to submit a detailed report
on this event including the remedial
measures taken to PCSC forum.
2. KPCL to check the excitation system of
Unit 8 of RTPS, and submit the remedial
measures
taken to PCSC forum.
KPCL/ MEPL/
APGENCO/
TNEB
TANGEDCO vide their mail dated 07.07.2015 informed
that as per the discussion and recommendation of 44th
meeting of PCSC held on 28.05.2015, a time delay of 2
Sec had been introduced for the above tripping for all the
ID fans at NCTPS-II.
MEPL vide their mail dated 14.09.2015 informed that
they have implemented 2 seconds delay for under voltage
tripping of all Drag Chain Feeder Conveyors. And this
has been done for both the Units.
Pending
42/II/18 Multiple
tripping at
Raichur
thermal
power station
of
KPCL
09-03-2015 at
06:36 hrs
400kV Raichur TPS-
Raichur(PG) line- 1&2, 400kV
Raichur-Mahboobnagar,
Unit#7 and ICT-2 at RTPS
tripped during the incident. B
phase to earth fault had occurred
in 400kV Raichur TPS-Raichur
line-1
1. KPCL to review REF setting (DMT or
IDMTL) for unit-7 by first week of April,
2015 and
inform the same to PCSC forum.
2. TSTRANSCO to furnish
Mehaboobnagar’s DR and EL and the
reasons for distance relay
operation at their end within a week’s
time.
3. PGCIL (SR-I) to rectify the issues
relating to A/R operation, relay reach
(Z2), reverse reach
(Z4) and SOTF auxiliary contacts within
a week’s time, and submit the actions
taken to
PCSC forum.
KPCL/TSTRA
NSCO/PGCIL
(SR-I)
ANNEXURE-III
Page 22 of 24
Tripping of
Unit-8 at
RTPS
24-05-2015
at 19:19 hrs
Tripped on Overvoltage.
PendingMEPL vide their mail dated 14.09.2015: informed the
following
1. Tan Delta Testing of winding and DGA of Insulating
Oil for all CTs was carried out and normal.
2. Could not find any problem during internal checks
hence we are in touch with ABB for rectification work.
Will be done by the end of 15th Oct'15
3. End to end testing of Carrier signals was carried out
and found them healthy.
MEPL/
PGCIL(SR-I)/
SEL
45/I/2
(GD)
Complete
outage of
MEPL power
station
20-05-2015 at
20:38 hrs
Y phase CT failure at MEPL led
to tripping of 400kV NPS-
MEPL, 400kV SEPL-MEPL line
and Unit-2 at MEPL. Uni-1 was
not in service at the time of
tripping
1. MEPL to ensure healthiness of all
CT’s by carrying out Tan Delta and DGA
tests wherever necessary.
2. MEPL to take suitable action to
correct the operation of tie-CB Bay
Control Unit that caused LBB/ BBP
operation.
3. PGCIL (SR-1) to carry out end-to-end
PLCC testing in coordination with MEPL
and ensure that carrier-aided protection
on MEPL – NPS line is in healthy
condition.
4. SEL to properly time-coordinate their
Over Current phase and Earth fault relays
in consultation with MEPL.
44/I/3
(GD)
1. All Tripped units, viz.,
Krishnapatinam, MEPL, Raichur,
NCTPS to submit a detailed report
on this event including the remedial
measures taken to PCSC forum.
2. KPCL to check the excitation system of
Unit 8 of RTPS, and submit the remedial
measures
taken to PCSC forum.
KPCL/ MEPL/
APGENCO/
TNEB
TANGEDCO vide their mail dated 07.07.2015 informed
that as per the discussion and recommendation of 44th
meeting of PCSC held on 28.05.2015, a time delay of 2
Sec had been introduced for the above tripping for all the
ID fans at NCTPS-II.
MEPL vide their mail dated 14.09.2015 informed that
they have implemented 2 seconds delay for under voltage
tripping of all Drag Chain Feeder Conveyors. And this
has been done for both the Units.
Pending
Yet to be informed Pending47/I/2
(GD)
Complete
outage of
Krishnapatna
m TPS
08-09-2015 at
18:20 hrs
As per FIR submitted, CT
damage observed in Chitoor-
Main bay (404). Main breakers
connected to bus-1 (401, 404,
407, 410) got tripped on
operation of bus bar protection.
Unit-1 tripped on operation of
MFT. Unit-2 was not in service
1. APGENCO to furnish to PCSC forum
(i) A3-size Single Line Diagram of
SDSTPS, and (ii) the sequence of
events with time stamp showing the
protection that opened Tie-CB (405) at
SDSTPS.
2. APGENCO to review STUB/TEED
protection in all dias at SDSTPS and
ensure that they are configured
for instantaneous operation.
3. APGENCO to properly configure the
STATE of the tripping events so that they
get recorded
appropriately like TRIP/ OPERATED in
their corresponding Event Loggers.
4. APGENCO to ensure time sync of all
DR’s and EL’s at SDSTPS.
5. PGCIL (SR-I) to provide line
differential protection for 400 kV NPS
–Nellore-PG lines 1 & 2.
APGENCO/
PGCIL (SR-I)
ANNEXURE-III
Page 23 of 24
47/II/9 Tripping of
400kV
Coastal-
NTPL line
and running
units
at NTPL
03-08-2015 at
15:43 hrs
R-phase to earth fault had
occurred in 400kV Coastal NTPL
line. Line autoreclosed at NTPL
end and failed to
reclose at Coatal end. Auto
reclose block was persisting due
to PLCC channel fail. Also
running Units-1&2 at NTPL
tripped on operation of GT
differential protection.
1. NTPL to ensure (i) proper DATE
settings, and (ii) time-sync with GPS for
DR and EL at NTPL.
2. CEPL to furnish remedial measures
taken regarding PLCC channel failure.
NTPL/ CEPL Yet to be informed Pending
PendingYet to be informedKPTCL/
KPCL/ NPCIL
47/II/7 Tripping of
220kV Kadra-
Karwar line-
1&2 and
220kV
Kaiga-Kadra
line
31-07-2015 at
11:44 hrs
220kV KAdra-Karwar lines-1&2
tripped
on earth fault in B-phase in zone-
2.
Kaiga-Kadra line tripped at
Kaiga end
only on operation of directional
eath
fault protection.
1. KPTCL/ KPCL to see the possibility of
implementing Weak Infeed logic with
Echo feature enabled by Under
Voltage (27) element on Kadra-Karwar
lines 1 &2, and implement the same if
feasible.
2. NPCIL to time-coordinate Kaiga’s
DEFR settings with (i) Zone-2 settings at
Kaiga, and (ii) primary protections of the
lines emanating from Kadra and
Kodasalli.
3. KPCL to ensure time-sync of EL’s, and
healthiness of the Fault Locators at
Kadra.
ANNEXURE-III
Page 24 of 24
Sl.No. Element NameOutage
date/time
Revival
date/time
Reason for
OutageSender/ Receiver
Remedial Measures/ Actions
taken
1220 kV AMBEWADI -
PONDA 123-06-2015/11:39:00
EARTH FAULT
RELAY
OPERATED
KPTCL/ GOA To-be-discussed
2
400 Kv
KRISHNAPATNAM -
NELLORE
20-07-2015/11:27:00 20-07-2015/12:00:00
BUS -1 TRIPPED :
REASON
AWAITED
APGENCO/
APTRANSCO/ PGCIL
(SR-I)
APGENCO: BUS-1 was tripped
at Power Grid Sub-
Station(PGCIL), Nellore during
the operation of the Isolators,
which is not pertaining to
APGENCO.
APTRANSCO: Line tripped at
Krishnapatnam end only.Line is
in service from Nellore-AP.
PGCIL (SR-I):
3400 kV VIJAYAWADA -
VTPS IV 126-07-2015/00:05:00
TRIPPED DUE
TO B-PHASE CT
BLAST
PGCIL(SR-I)/
APGENCO
APGENCO: This issue pertains
to PGCIL.
PGCIL(SR-I):
4GOOTY-
NELAMANGALA02-08-2015/09:18:00 02-08-2015/10:57:00
TRIPPED AT
SHOLAPUR END
ONLY.
KPTCL To-be-discussed
5400/220 kV ICT-1 AT
KAIGA04-08-2015/21:56:00
Y-PH LA
FAILUREKAPS To-be-discussed
6
220 kV
YERANDAHALLY -
HOSUR
17-08-2015/12:50:00 B-N FAULT KPTCL / TNEB
KPTCL: Transient fault. Stood
OK after test charging.
TANTRANSCO: Temporary
Fault and AR lockout at Hosur
end. The Feeder was normalized
at 13:14 Hrs.
Pending Remedial Measures/ Actions taken
for the Critical Tripping Incidents (as on 06.10.2015)
Annexure-IV
Page 1 of 10
7220 kV EDAMON -
EDAPPON18-08-2015/16:32:00 18-08-2015/17:01:00
TRIPPED ON Y-
PH FAULTKSEB
PGCIL (SR-II): Portion of the
line in which fault occured
owned and maintained by M/s
KSEB. May be clarified from M/s
KSEB.
KSEB:
8220 kV KUNDRA -
KAYAMKULAM18-08-2015/16:32:00
TRIPPED ON Y-
PH FAULTKSEB / NTPC
PGCIL (SR-II): Portion of the
line in which fault occured
owned and maintained by M/s
KSEB. May be clarified from M/s
KSEB.
KSEB:
9400 kV GUTTUR -
HIRIYUR 123-08-2015/10:01:00 23-08-2015/13:12:00
BUS BAR
CONNECTIONKPTCL/ PGCIL(SR-II) To-be-discussed
10400 kV NEYVELI TS 2 -
PUGALUR25-08-2015/16:09:00 25-08-2015/17:50:00
TRIPPED DUE
TO ARCHING ON
BUS-1
ISOLATOR AT
NLC
NLC/ PGCIL(SR-II)
PGCIL (SR-II): Tripped on
receipt of DT from TS2 end, (
Understood that due to isolator
problem at TS2 end.)
NLC:
11400 kV SRISAILAM-
MAMIDIPALLI 226-08-2015/15:40:00 26-08-2015/18:40:00 JUMPER CUT
TSGENCO/
TSTRANSCOTo-be-discussed
12400 kV KAIGA - GUTTUR
228-08-2015/15:17:00 28-08-2015/16:18:00 B - N FAULT KAPS/ KPTCL
PGCIL (SR-II): Portion of the
line in which fault occured
owned and maintained by M/s
KPTCL. May be clarified from
M/s KPTCL.
KPTCL:
13400 kV KHAMMAM -
KALPAKKA 103-09-2015/02:26:00 R-B FAULT
PGCIL (SR-I)/
APTRANSCOTo-be-discussed
Annexure-IV
Page 2 of 10
14 400 Kv HASSAN - UPCL 1 03-09-2015/11:23:00 03-09-2015/11:55:00 R-N FAULT PGCIL (SR-II)/ UPCL
PGCIL (SR-II): Line owned and
maintained by M/s KPTCL. May
be clarified from M/s KPTCL.
KPTCL:
15 400 Kv HASSAN - UPCL 1 03-09-2015/12:15:00 03-09-2015/15:19:00 R-N FAULT PGCIL (SR-II)/ UPCL
PGCIL (SR-II): Line owned and
maintained by M/s KPTCL. May
be clarified from M/s KPTCL.
KPTCL:
16220 kV SABARGIRI -
THENI04-09-2015/13:23:00 04-09-2015/13:56:00 Y -N FAULT
KSEB/
TANTRANSCO
TANTRANSCO: Temporary
fault. AR lockout at Theni end.
Feeder normalised at 13:56 hrs.
KSEB:
17400 kV GAJWEL -
HYDERABAD05-09-2015/08:09:00 05-09-2015/08:44:00
TRIPPED DUE
TO MAL
OPERATION OF
REACTOR WTI
AT HYD
TSTRANSCO/
PGCIL(SR-I)To-be-discussed
18400 Kv VIJAYAWADA -
NELLORE - AP - 305-09-2015/14:43:00 05-09-2015/15:59:00 B - N FAULT
PGCIl (SR-I)/
APTRANSCOTo-be-discussed
19220 kV KANIAMPET -
KADAKOLA05-09-2015/12:05:00 05-09-2015/12:25:00
TRIPPED ON R-
PH FAULTKSEB/ KPTCL
KPTCL: Transient fault. Stood
OK after test charging.
KSEB:
20400 Kv VIJAYAWADA -
NELLORE - AP -06-09-2015/15:01:00 06-09-2015/15:07:00 B-N FAULT
PGCIl (SR-I)/
APTRANSCOTo-be-discussed
21400 kV TRIVENDRUM -
TIRUNELVELI 207-09-2015/16:50:00 07-09-2015/17:09:00
MALOPERATIO
N OF DTPGCIL (SR-II)
PGCIL (SR-II): PLCC mal-
operation at TVM end. Rectified
the faulty card.
Annexure-IV
Page 3 of 10
22220 Kv REGULAPADU-
ALIPUR LINE07-09-2015/03:23:00 07-09-2015/04:32:00 EFR ACTED
APTRANSCO/
KPTCL
KPTCL: Transient fault. Stood
OK after test charging.
APTRANSCO:
23400 kV RAMAGUNDAM -
CHANDRAPUR 207-09-2015/22:20:00
DISTANCE
PROTECTION
ACTED
NTPC/ PGCIL (WR-I) To-be-discussed
24400 kV TRIVENDRUM -
TIRUNELVELI 207-09-2015/16:36:00 07-09-2015/16:47:00
MALOPERATIO
N OF DTPGCIL (SR-II)
PGCIL (SR-II): PLCC mal-
operation at TVM end.
25 400 Kv BTPS - YTPS 08-09-2015/15:58:00 08-09-2015/17:27:00 R-N FAULT KPCL To-be-discussed
26400 kV KHAMMAM -
KALPAKKA 208-09-2015/15:37:00 08-09-2015/15:54:00
TRIPPED AT
KLPA END
ONLY
PGCIL (SR-I)/
APTRANSCOTo-be-discussed
27 400 Kv RAICHUR - YTPS 08-09-2015/15:58:00 08-09-2015/17:22:00 R-N FAULT KPCL To-be-discussed
28
400 Kv
KRISHNAPATNAM -
CHITTOOR -2
09-09-2015/09:04:00 09-09-2015/09:52:00 DT RECEIVEDAPGECNO/
APTRANSCOTo-be-discussed
29400 Kv VTPS -
MALKARAM 110-09-2015/11:27:00 10-09-2015/11:37:00
TRIPPED AT
MLKRM END
ONLY
APGENCO/
TSTRANSCOTo-be-discussed
30220 KV BHAVINI -
SIRUSERI 210-09-2015/00:48:00 10-09-2015/01:34:00 R-N FAULT
NPCIL/
TANTRANSCOTo-be-discussed
31400 kV KAIGA - GUTTUR
110-09-2015/15:21:00 10-09-2015/19:16:00
TRIPPED ON B-
PH FAULTKAPS/ KPTCL
PGCIL (SR-II): Portion of the
line in which fault occured
owned and maintained by M/s
KPTCL. May be clarified from
M/s KPTCL.
KPTCL:
32220 kV SEDAM -
TANDUR10-09-2015/16:35:00 10-09-2015/19:15:00
TRIPPED DUE
TO LOSS OF
INFEED AT
SEDAM
KPTCL/
TSTRANSCOTo-be-discussed
Annexure-IV
Page 4 of 10
33400 kV RAMAGUNDAM -
HYDERABAD 411-09-2015/22:26:00 11-09-2015/23:02:00
PLCC
MALOPERATIO
N
NTPC/ PGCIL (SR-I) To-be-discussed
34400 kV KAIGA - GUTTUR
112-09-2015/11:07:00 12-09-2015/11:55:00
TRRIPPED ON B-
PH FAULTKAPS/ KPTCL
PGCIL (SR-II): Portion of the
line in which fault occured
owned and maintained by M/s
KPTCL. May be clarified from
M/s KPTCL.
KPTCL:
35 400 Kv HASSAN - UPCL 1 12-09-2015/13:48:00 12-09-2015/14:48:00 B - N FAULT PGCIL (SR-II)/ UPCL
PGCIL (SR-II): Line owned and
maintained by M/s KPTCL. May
be clarified from M/s KPTCL.
KPTCL:
36400 kV TALAGUPPA -
NEELAMANGALA14-09-2015/11:21:00
TRIPPED ON Y-N
FAULTKPTCL To-be-discussed
37400 kV GOOTY -
NELAMANGALA15-09-2015/23:55:00 16-09-2015/00:13:00
TRIPPED ON R-
PH FAULTPGCIL (SR-I)/ KPTCL To-be-discussed
38400 Kv IL&FS -
NAGAPATTANAM-115-09-2015/10:51:00 15-09-2015/13:39:00 Y-N FAULT IL&FS/ PGCIL (SR-II) To-be-discussed
39400/220 kV ICT-1 AT
CHITTOOR15-09-2015/16:55:00 15-09-2015/19:51:00
WHILE CLOSING
BUS COUPLER
AUTO TRIP
COMMAND
SENT TO ICT'S
APTRANSCO To-be-discussed
40400/220 kV ICT-2 AT
CHITTOOR15-09-2015/16:55:00 15-09-2015/19:58:00
WHILE CLOSING
BUS COUPLER
AUTO TRIP
COMMAND
SENT TO ICT'S
APTRANSCO To-be-discussed
Annexure-IV
Page 5 of 10
41400 kV GAJWEL -
HYDERABAD17-09-2015/01:45:00
TRIPPED ON Y-N
FAULT
TSTRANSCO/ PGCIL
(SR-I)To-be-discussed
42400 kV KAIGA - GUTTUR
117-09-2015/14:55:00
TRIPPED ON
DISTANCE
PROTECTION
KAPS/ KPTCL To-be-discussed
43400 KV ALAMATHI -
THIRUVALLAM-117-09-2015/16:45:00
TRIPPED ON
LINE TO
GROUND FAULT
TANTRANSCO To-be-discussed
44400 kV GUTTUR -
HIRIYUR 218-09-2015/10:33:00 18-09-2015/11:01:00
D/T RECEIVED
FROM HIRIYUR
END
KPTCL/ PGCIL (SR-
II)To-be-discussed
45400 kV KAIGA - GUTTUR
119-09-2015/13:55:00 19-09-2015/14:59:00
TRIPPED ON B-
PH FAULTKAPS/ KPTCL To-be-discussed
46400 kV GUTTUR -
HIRIYUR 219-09-2015/09:40:00 19-09-2015/09:55:00
TRIPPED AT
GUTTUR END
ONLY
KPTCL/ PGCIL (SR-
II)To-be-discussed
47400 Kv GAJWEL -
SHANKARPALLY 220-09-2015/02:24:00 20-09-2015/04:27:00 LINE FAULT TSTRANSCO To-be-discussed
48400 kV KAIGA - GUTTUR
121-09-2015/11:26:00 21-09-2015/12:10:00
TRIPPED ON B-N
FAULTKAPS/ KPTCL To-be-discussed
49220 Kv CHIKKODI -
MUDUSHINGI21-09-2015/10:58:00 21-09-2015/17:35:00
TRIPPED ON PH-
PH FAULTKPTCL To-be-discussed
50400 kV VIJAYAWADA -
VEMAGIRI 121-09-2015/17:20:00 21-09-2015/17:44:00
TRIPPED ON
PLCC TESTING
PGCIL (SR-I)/
APTRANSCOTo-be-discussed
51400 kV GUTTUR -
NARENDRA 222-09-2015/13:53:00 22-09-2015/14:19:00
DT RECIEVED
AT GUTTUR
END
KPTCL/ PGCIL (SR-
II)To-be-discussed
52400/230 Kv ICT-1 AT
ARASUR22-09-2015/15:01:00 22-09-2015/17:24:00
TRIPPED ON
OVER LOADINGPGCIL (SR-II) To-be-discussed
Annexure-IV
Page 6 of 10
53400/230 Kv ICT-2 AT
ARASUR22-09-2015/15:01:00 22-09-2015/16:52:00
TRIPPED ON
OVER LOADINGPGCIL (SR-II) To-be-discussed
54220 kV KANIAMPET -
KADAKOLA22-09-2015/22:30:00 22-09-2015/22:51:00
TRIPPED ON
DISTANCE
PROTECTION
KSEB/ KPTCL To-be-discussed
55400 kV GUTTUR -
HIRIYUR 123-09-2015/10:32:00 23-09-2015/12:46:00 DT RECEIVED
KPTCL/ PGCIL (SR-
II)To-be-discussed
56400 kV GUTTUR -
HIRIYUR 123-09-2015/15:45:00 23-09-2015/16:24:00
DT RECEIVED
AT GUTTUR
END
KPTCL/ PGCIL (SR-
II)To-be-discussed
57220 kV KANIAMPET -
KADAKOLA23-09-2015/12:06:00 23-09-2015/12:36:00 B-N FAULT KSEB/ KPTCL To-be-discussed
58400/220 kV ICT-2 AT
GUTTUR23-09-2015/10:48:00 23-09-2015/13:27:00
RELAY
MALOPERATIO
N
KPTCL To-be-discussed
59220 kV KANIAMPET -
KADAKOLA24-09-2015/04:20:00
TRIPPED DUE
TO BREAKER
PROBLEM-POLE
DISCREPENCY
KSEB/ KPTCL To-be-discussed
60400 Kv NELLORE -
THIRUVALLAM 124-09-2015/10:52:00 24-09-2015/11:49:00
DT RECEIVED
AT THVLM
PGCIL (SR-I)/ PGCIL
(SR-II)To-be-discussed
61400/220 kV ICT-2 AT
VISAKHAPATNAM24-09-2015/18:09:00 24-09-2015/18:44:00
220 KV SIDE
BUS BAR
PROTECTION
OPERATED
PGCIL (SR-I) To-be-discussed
62220 kV AMBEWADI -
PONDA 124-09-2015/13:20:00 24-09-2015/17:25:00 B-N FAULT KPTCL/ GOA To-be-discussed
63400/220 Kv ICT-2 AT
SATTENAPLLI24-09-2015/08:33:00 24-09-2015/11:26:00
RELAY
MALOPERATIO
N
APTRANSCO To-be-discussed
64400 kV GAJWEL -
HYDERABAD25-09-2015/23:18:00 25-09-2015/23:34:00
TRIPPED ON B-N
FAULT
TSTRANSCO/ PGCIL
(SR-I)To-be-discussed
Annexure-IV
Page 7 of 10
65400 kV VIJAYAWADA -
NELLORE 125-09-2015/10:10:00 25-09-2015/10:55:00 Y-N FAULT PGCIL (SR-I) To-be-discussed
66
400 Kv
KRISHNAPATNAM -
CHITTOOR -1
25-09-2015/21:34:00 25-09-2015/22:09:00TRIPPED ON R-N
FAULT
APGENCO/
APTRANSCOTo-be-discussed
67400 Kv NAGAPATNAM-
TIRCHY-126-09-2015/15:14:00 26-09-2015/15:30:00
TRIPPED ON Y-
PH FAULTPGCIL (SR-II) To-be-discussed
68400 Kv SATTENAPALLI -
SRISAILAM 126-09-2015/16:45:00
TRIPPED ON R-
PH FAULT
APTRANSCO/
TSGENCOTo-be-discussed
69400 Kv KAYATHAR -
KARAIKUDI 226-09-2015/15:16:00 26-09-2015/17:54:00
TRIPPED ON R-
PH FAULT
TANTRANSCO/
PGCIL (SR-II)To-be-discussed
70400 Kv KAYATHAR -
KARAIKUDI 126-09-2015/17:05:00 26-09-2015/17:46:00
TRIPPED ON R-
PH FAULT
TANTRANSCO/
PGCIL (SR-II)To-be-discussed
71220 kV AMBEWADI -
PONDA 127-09-2015/15:53:00 27-09-2015/16:38:00
DUE TO BUS
DEAD AT
AMBAWADI
STATION
KPTCL/ GOA To-be-discussed
72220 kV AMBEWADI -
PONDA 227-09-2015/15:53:00 27-09-2015/18:43:00
DUE TO BUS
DEAD AT
AMBAWADI
STATION
KPTCL/ GOA To-be-discussed
73400 KV ALAMATHI -
THIRUVALLAM-127-09-2015/11:32:00 27-09-2015/16:53:00
TRIPPED DUE
INSULATOR
DECAPPING
TANTRANSCO To-be-discussed
74400 kV KAIGA - GUTTUR
127-09-2015/14:52:00
TRIPPED ON B-
PH FAULTKAPS/ KPTCL To-be-discussed
75400 kV KAIGA - GUTTUR
228-09-2015/16:32:00 28-09-2015/17:18:00 B - N FAULT KAPS/ KPTCL To-be-discussed
76400 Kv KAYATHAR -
KARAIKUDI 228-09-2015/15:42:00 28-09-2015/16:24:00 Y- N FAULT
TANTRANSCO/
PGCIL (SR-II)To-be-discussed
Annexure-IV
Page 8 of 10
77400 kV WARANGAL -
KHAMMAM29-09-2015/17:06:00 29-09-2015/18:27:00
PLCC
MALOPERATIO
N
PGCIL (SR-I) To-be-discussed
78765 KV KURNOOL -
THIRUVALLM 229-09-2015/12:57:00 29-09-2015/15:39:00
REF
PROTECTION
ACTED
PGCIL (SR-I)/ PGCIL
(SR-II)To-be-discussed
79400 kV NEYVELI TS 2
(EXP) - PUGALUR29-09-2015/16:42:00 29-09-2015/17:24:00 R - N FAULT NLC/ PGCIL (SR-II) To-be-discussed
80400 kV KAIGA - GUTTUR
129-09-2015/12:02:00 29-09-2015/12:45:00
TRIPPED ON B-
PH FAULTKAPS/ KPTCL To-be-discussed
81220 kV AMBEWADI -
PONDA 230-09-2015/10:41:00 30-09-2015/11:03:00
BUS DEAD AT
AMBEWADI
END
KPTCL/ GOA To-be-discussed
82400 kV GUTTUR -
HIRIYUR 230-09-2015/10:12:00 30-09-2015/11:56:00
PLCC
MALOPERATIO
N
KPTCL/ PGCIL (SR-
II)To-be-discussed
83220 kV AMBEWADI -
PONDA 130-09-2015/10:41:00 30-09-2015/11:03:00
BUS DEAD AT
AMBEWADI
END
KPTCL/ GOA To-be-discussed
84220 Kv CHIKKODI -
MUDUSHINGI01-10-2015/20:10:00 Y-N FAULT KPTCL To-be-discussed
85220 kV SABARGIRI -
THENI02-10-2015/16:31:00 02-10-2015/16:59:00
DISTANCE
PROTECTION
KSEB/
TANTRANSCOTo-be-discussed
86400 KV ALAMATHI -
THIRUVALLAM-102-10-2015/18:36:00 R-N FAULT TANTRANSCO To-be-discussed
87400 kV WARANGAL -
BOOPALPPALLI 104-10-2015/14:42:00 04-10-2015/15:52:00
TRIPPED ON B-
PH FAULT
PGCIL (SR-I)/
APTRANSCOTo-be-discussed
88400 kV KAIGA - GUTTUR
204-10-2015/14:27:00
TRIPPED ON B-
PH FAULTKAPS/ KPTCL To-be-discussed
89400 Kv PONDY-
SVCHATRAM04-10-2015/22:55:00 Y-N FAULT PGCIL (SR-II) To-be-discussed
Annexure-IV
Page 9 of 10
90 400 Kv NCTPS - SVCTM-I 05-10-2015/14:31:00 05-10-2015/15:44:00TRIPPED ON R-
PH FAULT
TANGEDCO/
TANTRANSCOTo-be-discussed
91400 Kv SATTENAPALLI -
SRISAILAM 205-10-2015/16:24:00 B-PH FAULT
APTRANSCO/
TSGENCOTo-be-discussed
Annexure-IV
Page 10 of 10
S.
No
Name of
Substation Details of work Status of Implementation of Protection Audit Recommendations Remarks
1 220 KV- Dr.
NTTPS, Stage-I,
220 KV Switch
yard. VTS
Only 220 V DC Source with one battery
set is available for entire 220 kV SS.It is
recommended to have redundant DC
source.
Redundant 220 kV DC supply is available from station Battery Bank. Pending
7 230 kV Basin
Bridge Substation No Earth fault protection on HV & LV
side of transformer. Same to be providedE/F settings for AUTOs not being adopted in TANTRANSCO. Pending
8 230 kV Ennore
(ETPS) Earth fault relay to be provided on HV &
LV sides of Auto t/p # 1, 2 and TO # 3 t/f.
Over fluxing relayto be provided.
E/F settings for AUTOs not being adopted in Tantransco. Pending
9 230 kV Korattur
Substation No E/L relay protection on ATR 1, 2 & 3
HVs. Same to be providedE/F settings for AUTOs not being adopted in Tantransco. Pending
10 230 kV Mylapore
Substation No Earth fault protection on HV & LV
side. Same to be reviewed and providedE/F settings for AUTOs not being adopted in Tantransco. Pending
11 230 kV Tondiarpet
Substation 100 MVA, 230/110 kV transformer # 1
&2, back up O/C relays setting need
review. Earth fault relays to be provided
on both HV & LV side of ICT's
Uniform setting adopted for O/C. E/F settings for AUTOs not being adopted in
TantranscoPending
Review of implementation of certain Protection Audit Recommendations of
SR-Constituents (PCSC-47)
APGENCO (THERMAL) [Phase-II]
TANGEDCO (Phase-I)
TANTRANSCO (Phase-I)
Annexure-V
1
Additional Agenda for 48th PCSC meeting Page 1
SOUTHERN REGIONAL POWER COMMITTEE
BENGALURU
Additional Agenda for the 48th
meeting of Protection Coordination Sub-Committee (PCSC-
48) of SRPC to be held on 29.10.2015
1. Non- furnishing of Tripping Details
The members were intimated about non- furnishing of tripping details for the grid incidents that occurred
during the period 1st - 15
th October, 2015 vide SRPC letter dated 20.10.2015 (Annexure-VI). The issue
would be discussed in the meeting.
2. Review of implementation of certain Protection Audit Recommendations of APTRANSCO
APTRANSCO vide their letter dated 01-10-2015, requested to drop certain protection audit
recommendations of their 220 kV Bommur and 400 kV Kurnool Substations. In this regard, PCSC forum may appropriately review the recommendations given at Annexure-VII.
3. Provision of Auto-Reclosure on lines (400 kV & 220 kV) emanating from Kaiga NPP
A special meeting was held at SRPC, Bengaluru on 20-10-2015 to discuss grid related issues with
representatives of NPCIL, CTU and APTRANSCO as a follow-up to 28th SRPC meeting held on
10-10-2015. During the deliberations relating to providing Auto-Reclosure on lines (400 kV & 220 kV)
emanating from Kaiga NPP, the following were noted:
As regards A/R provision on
220 kV lines emanating from Kaiga (U1 & U2), their representative informed
that they are ready to provide A/R from Kaiga end, however, readiness from
the other ends, viz., Kadra and Kodasalli needed to be found out. Further,
closing of Kodasalli – Nagjheri line from Nagjheri end also needs to be
considered for better reliability.
400kV Kaiga- Guttur D/C, their representative informed that even though they
are ready to provide A/R from Kaiga end, the same cannot be put into service
until the trippings on these lines are brought down to minimum by KPTCL. The
KPTCL management has been apprised of the severity of the issue and
affirmative action from them in this regard is still awaited.
After deliberations, it was decided that the issue would be discussed in detail in the
forthcoming Protection Co-ordination Sub-Committee meeting.
Accordingly, it is proposed to further deliberate on the above issue.
4. Meeting of Standing Committee of Experts to investigate the failure of equipment at 220 kV and
above substations
It is intimated that the meeting of Standing Committee of Experts to investigate the failure of equipment
at 220 kV and above substations would be held on 4th November, 2015 at 2:30 PM in Conference Room, 6
th
Floor (North), CEA, Sewa Bhawan, R.K Puram, New Delhi (Annexure-VIII). Members may kindly note.
*****
Annexure-VI
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Annexure-VI
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Annexure-VI
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Annexure-VI
Page 4 of 10
Annexure-VI
Page 5 of 10
Annexure-VI
Page 6 of 10
Annexure-VI
Page 7 of 10
Annexure-VI
Page 8 of 10
Annexure-VI
Page 9 of 10
Annexure-VI
Page 10 of 10
Review of implementation of certain Protection Audit Recommendations
of APTRANSCO
Name of
the SS
Protection audit observations Remarks
400KV
Nannur
item 5, of
Phase I.
400KV Kurnool (Nunnur) Gooty
feeder main I protection on SEL-
421 the “out of step
tripping/blocking”. Settings are
different from approved settings.
This is to be reviewed.
This line pertaining to PGCIL and hence
may be dropped from the list.
220KV
Bommur
item 3 of
phase1.
REF is not used in
APTRANSCO for 220KV
substations
At present differential protection is used
as a main protection and O/C & E/F
protection as a back up protection for the
PTRs at 220KV level. REF protection is
being used as an additional protection by
using bushing CTs of PTR at 400KV
level. For providing REF protection for
the existing PTRs at 220KV Bommur SS
transformer neutral side CTs are to be
provided. And also spare core is not
available on the phase side CTs for REF
protection. So the CTs on Phase side
also need to be replaced. There will be
clearance problem and constraint of place
in the event of erection of neutral side
CTs. This will have cumulative effect in
the yard. Hence the proposal for
providing REF protection for the existing
transformers at 220KV level may be
dropped.
ANNEXURE-VII
ANNEXURE-VIII