tangedco, ped, ntpc (kayamkulam), maps, ntecl, ntpl, sel, cepl & mepl. 5. network configuration...

SOUTHERN REGIONAL POWER COMMITTEE

BENGALURU

Agenda for the 50

th Meeting of Protection Coordination Sub-Committee of

SRPC to be held on 29.12.2015 (Tuesday)

1. Introduction

2. Confirmation of Minutes of last PCSC meeting

Confirmation of minutes of 49th

Protection Coordination Sub-Committee meeting

held on 30.11.2015.

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 period November - December, 2015 given at Annexure-I would be discussed in

the PCSC meeting

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 of the tripping events

pertaining to their system.

3.2 In compliance of Regulations 5.2 (r) of IEGC, the Constituents are required to

furnish the following information in respect of Grid Occurrences:

(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 has been brought to Constituents attention vide SRPC letter

letter No. SRPC/ SE-III/ PCSC-50/ 2015/ 8687-719 dated 03-12-2015. The non-

compliance in this regard 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 49th

PCSC) given at Annexure-II may please be sent latest by 25.12.2015.

Agenda for the 50th Protection Coordination Sub Committee Meeting to be held on 29-12-2015 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-III)

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 November, 2015 is still awaited from the

following SR-Constituents:

APGENCO (Thermal), APTRANSCO, TSGENCO (Thermal), KPTCL,

TANGEDCO, PED, NTPC (Kayamkulam), MAPS, NTECL, NTPL, SEL,

CEPL & MEPL.

5. Network Configuration changes

As per the information furnished by SR-Constituents to the OCC forum in their 113th

meeting held on 06.11.2015 (Minutes circulated on 30.11.2015), the following network

configuration changes (additions/ deletions/ modifications of transmission elements) took

place in the southern grid during the month of October, 2015.

COD 220 kV Appayyadorapalem (ADR Palem) in Vizianagaram district was

commissioned on 15.10.2015 by APTRANSCO

220/132 kV Miyapur S/s of 1x160 MVA Transformer Capacity was augmented to

2x160 MVA Transformer Capacity on 07.09.2015 by TSTRANSCO.

220 KV D/C XLPE UG Cable from 220 kV Moulali SS to 220 KV GIS at Osmania

University in Hyderabad of ckm 17.926 was commissioned on 14.10.2015 by

TSTRANSCO.

220 KV line on Narrow Based Multi Circuit Towers with 4 Circuits for LILO of both

Circuits of Dindi - Chandrayangutta 220 KV D/C Line to the proposed 220 kV SS,

Bonguloor of ckm 2 was Commissioned on 31.10.2015 by TSTRANSCO.

LILO of 220kV Ramagundam- Mandamarry circuit-I to 220/6.6kV LI SS Murmur in

Karimnagar district of 3.9 ckm was commissioned on 21.10.2015 by TSTRANSCO.

220 KV 2nd ckt stringing from 220 KV RSS 220 KV Mandamarry (34 KM) in

Karimnagar of 34 ckm was commissioned by 20.10.2015 by TSTRANSCO.

LILO of 220kV Ogulapur- Durshed to 220/6.6kV LI SS Bommakal in Karimnagar

district of 0.108 ckm was commissioned on 27.10.2015 by TSTRANSCO.

http://srldc.in/DailyReport.aspx


220/132 KV GIS Osmania University in Chilakalaguda, Hyderabad was

commissioned on 14.10.2015 by TSTRANSCO.

220/6.6KV Murmur LI substation in Karimnagar district was commissioned on

21.10.2015 by TSTRANSCO.

220/6.6KV Bommakal LI substation in Karimnagar district was commissioned on


220/6.6KV Mallaram LI substation in Medak district was commissioned on


220/132 KVSS Bonguluru in Ranga Reddy Dist. (originally charged with

1x100MVA) was commissioned on 31.10.2015 by TSTRANSCO.

PGCIL vide their letter dated 16.10.2015 informed that consequent to the successful

completion of Trial Operation, Transmission system associated with Kaiga 3 & 4

(2x235 MW) Project (Mysore-Kozhikode 400 D/C line along with new 400/220 kV

S/S with 2x315 MVA ICTs and 2x50 MVAR switchable line reactors at Kozhikode and

associated bay equipment at Mysore Substation) had been put under COD w.e.f 00:00

hours of 16th October 2015 in terms of Clause 4 of CERC(Terms and Conditions of

Tariff) Regulations 2014.

6. Compliance of Hon’ble CERC Orders.

6.1 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).

6.2 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.

http://www.srpc.kar.nic.in/website/2014/operation/patrolling.pdf


6.3 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.

6.4 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.”

“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.”

6.5 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.”

6.6 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.

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.


7. Other Protection Issues, if any, with the permission of the Chair

8. 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.

9. Date of next PCSC meeting

The 51st PCSC meeting would be conducted on 27.01.2016 (Wednesday) at

Trivandrum, Kerala.

*******

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

Complete outage of

220kV Somanahalli

substation of

KPTCL

27-11-2015

at 18:47 hrs

Bus bar protection got operated

due to wrong bus bar zone

selection resulting in tripping of

both the 220kV bus at 220kV

Somanahalli substation

Load loss : 650MW

GD-1

2. ग्रिडडडस्टर्बन्स / ग्रिडइन्सडन्टकावििरण - Details of Grid incidents:

Sr. No.

क्र.

सं.

घटनाकावििरण / Details

of Event





1

Tripping of 220kV

Ambewadi-Ponda

line-2 04-11-2015at

13:09 hrs Line tripped on operation of

DEFR protection

2

Tripping of 400kV

Alamathy-

S.V.Chatram line-2 08-11-2015

at 10:48 hrs

Line tripped on D.T. receive on

CHANNEL-2 at SV.Chatram end

when the operator at

ALAMATHY S/S end tried to

close Alamathy-SVChatram-1&2

Feeder Tie Breaker. Suspected

DC earth fault had caused the

initiation of direct trip.

3

Tripping of

400/220kV ICT-2 at

Chitoor substation 10-11-2015

at 00:53 hrs ICT-2 tripped on operation of

overflux protection

4

Tripping of ICT’s-1,

2, 3 & 4 at Salem

substation

10th Nov

2015 at

02:29hrs, 349

hrs, 3:53

hrsand 11th

Nov 2015 at

4:42 hrs

ICT’s tripped on operation of

overflux protection

5

Tripping of 400kV

NPS-NELLORE

line-1 10-11-2015

at 15:37 hrs line tripped due to suspected DC

earth fault at Nellore end and sent

direct trip was sent to NPS

6 Tripping of HVDC

Bhadrawati pole-2

11-11-2015

at 5:35 hrs

HVDC bhadrawati pole-2 tripped

due to non-valid tap code alarm. GI-2

7 Tripping of 400kV

Kolar-Hoody line-1

11-11-2015

at 15:39 hrs

Line tripped on operation of over

voltage protection and pole

discrepancy at Hoody end and

Annexure-I

Page 1 of 4

direct trip was received at Kolar.

8

Tripping of 400kV

Gooty-

Neelamangala line

12-11-2015

at 00:20 hrs

R-phase toearth fault had occurred

in Line. Line did not auto-reclose

from both ends. It was mentioned

that Y&B pole breakers at

Neelamangala tripped on

operation of pole discrepancy and

backup impedence protection for

line reactor got operated.

9

Tripping of Unit-

3&4 at Simhapuri

power station

12-11-2015at

13:51 hrs

Unit-3 and Unit-4 got tripped due

to operation of Local Breaker

Backup (LBB) protection in both

GT-3 and GT-4 Bays

10

Tripping of

765/400kV ICT-2 at

Nellore pooling

station

14-11-2015at

1:03 hrs

765/400kV ICT-2 at Nellore

pooling station tripped due to

maloperation of PRD-OLTC

Pressure High Trip Bph

11

Tripping of 400kV

Neyveli TS2-Pugalur

line

14-11-2015at

4:01 hrs

Line tripped on operation of over

voltage protection at Pugalur end.

However from DR it was

observed that the voltages were

below the O/v stg-1 threshold

limits

12

Tripping of 400kV

Nellore-Tiruvelam

line-1

14-11-2015

at 14:04

hrsand at

12:12 hrs on

24-11-2015

line tripped due to suspected Mal-

operation of Line reactor PRD at

Nellore end

13

Tripping of 400kV

Nellore-NPS line-1

16-11-2015

at 17:28 hrs

and 17:52 hrs

line tripped due on protection

system mal-operation due to

heavy rain at Nellore

14

Tripping of 220kV

Chitoor-Tiruvelam

18-11-2015

at 11:20 hrs

During testing of DC earth

leakage, DC got extended to bus

bar protection relay. Hence bus

bar protection operated and

tripped the 220KV BUS

connected transformers and

feeders.

15

Tripping of

400/220kV ICT-3 at

Udumalpet

substation

27-11-2015

at 11:21 hrs

ICT-3 Bus Voltage selection

Relay 75B and 75D Y ph contacts

failed to operate . Due to that the

over flux relay of ICT 3 operated

and initiated the Group A and B

relays. T

16

Tripping of 400kV

Alamathy-

S.V.Chatram line-

1&2

27-11-2015

at 15:35 hrs

400KV Aalmathy-S.V.Chatram

line-2 Line tripped on R-phase to

earth fault. Line autoreclosed at

S.V.Chatram and failed to auto-

reclose at S.V.Chatram end.

17

Tripping of

400/230kV

Udumalpet ICT-3

27-11-2015

at 17:26 hrs

400/230kV Udumalpet ICT-3

Tripped due to the operation of

230KV CB LBB protection at 230

KV bus (TNEB) of Udumalpet

station.

Annexure-I

Page 2 of 4

Sr. No.

क्र.

सं.


of Event





18

Tripping of 400kV

UPCL-Hassan line-2

and running Units-

1&2 at Udupi power

station

30-11-2015

at 17:22 hrs

400kV Hassan-Udupi line-2

tripped on Directional earth fault

protection with Y-E fault and

direct trip was sent to Udupi end.

Directional Earth fault feature of

Main-2 relay at hassan gave 3

phtrip after 2.6 seconds and fault

current in Y-phase was 1.1 kA.

The distance as well as DEF

protection for 400kV UPCL-

Hassan line-2 at UPCL end did

not sense the fault. The generator

transformer backup earth fault

protection (51N) had sensed the

fault and tripped both the running

units at UPCL leading to

generation loss at UPCL power

station. Back up directional earth

fault protection at 220kV side of

400/220kV ICT’s at UPCL did

not sense the high resistance fault

in line-2

Generation loss : 1100 MW

GI-2

19

Tripping of 400kV

Bus-2 at Kalpakka,

400kV Sinhadiri-

Kalpakka-4, 400kV

Vemagiri-Kalpakka-

2, ICT-2 at Kalpakka

10-12-2015

at 15:20 hrs

While testing new 400kV Hinduja

Power station feeder bay in the

yard, trip pulse got extended to

Bus-2 of Busbar protection and all

connected feeders to Bus-2 got

tripped

GI-2

3. Failure or non-operation of Auto reclose during transient fault

Sr. No.

Element Date & Time

Reason

1

Tripping of 400kV Gajwel-

Shankarapalli line-1

02-11-2015 at

11:33hrs and 12:22

hrs

Line tripped on a R-phase to earth

fault and fault was persistent.

From PMU data it was observed

that the breaker tried two auto-

reclose attempts after dead time.

2

Tripping of 220kV

Kaniambeta-Kadakola line 04-11-2015at 12:38

hrs Line tripped on a B-phase to earth

fault. There is no provision for

auto-reclose for line

3

Tripping of 220kV Ambewadi-

Ponda line

11-11-2015 at

11:32hrs

Line tripped on a B-phase to earth

fault. There is no provision for

auto-reclose.

Annexure-I

Page 3 of 4

4

Tripping of 400kV NCTPS-

S.V.Chatram line-1 16-11-2015 at

17:24 hrs Line tripped on a Y-phase to earth

fault. Line auto-reclosed at

S.V.Chatram and failed to auto-

reclose at NCTPS. It was

mentioned in FIR of NCTPS that

the tie breaker was under

shutdown.

5

Tripping of 400kV

Krishnapatnam-Chitoor line-1

16-11-2015 at

18:49 hrs Line tripped on a permanent fault

in R-phase. Chitoor end attempted

for auto-reclose however

krishnapatnam end went for a 3

phase trip and did attempt for

auto-reclose.

6

Tripping of 220kV

Gumidipoondi- Sulurupeta line

03-12-2015 at

09:05hrs

Line tripped on a Y-phase to

ground fault. There is no

provision for auto-reclose for line.

4. Lines tripping due to tripping at one end/PLCC mal-operation

Sr. No.

क्र.

सं.


of Event





1 Tripping of 400kV

Pugalur-Karaikudi 8-11-2015 at

13:51hrs

line tripped at Karaikudi and was

holding from Pugalur due to

suspected PLCC mal-operation at

Karaikudi end.

2

Tripping of 400kV

Krishnapatnam-

Chitoor line-2

21-11-2015at

7:18 hrs

Line tripped at Krishnapatnam

end only on pole discrepancy

operation

*****

Annexure-I

Page 4 of 4

Meeting

No /

Index

Details of

Event

Date Reason PCSC Recommendations Utility

Responsible

for

implementat

ion

Status of Recommendations

as on 14-12-2015

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.

APTRANSC

O

Yet to be informed Pending

APTRANSC

O

APTRANSCO to furnish a report on the

tripping of 400 kV Vemagiri – Sattenapalli line

along with relevant DR & EL showing clearly

the successful operation of A/R followed by T-

LBB/ OVR, Stage-I operation.

Pending Implementation of PCSC Recommendations (30th to 49th)

Andhra Pradesh42/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.

APTRANSC

O

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

B-phase to earth fault had occurred

in line. From Vemagiri end D.R,

three phase trip and Tie-CB LBB

operated was observed.

Sattenapalli end had auto-reclosed,

however breaker at Satenapalli

tripped 8 sec after A/R on receipt

of DT from Vemagiri as observed

from EL of Satenapalli station.

For 400k Vemagiri-Kalpakka line

at Vemagiri end, Tie LBB

operation and Grp-A/B trip was

observed and direct trip was sent to

Kalpakka end

25-10-2015

at 10:56 hrs

Tripping of

400kV

Vemagiri-

Sattenapalli

line and

400kV

Vemagiri-

Kalpakka line

49/II/8 PendingYet to be informed

Annexure-II

Page 1 of 24


running Units

1 & 3 at

Rayalaseema

TPS of

APGENCO

31-10-2015

at 03:30 hrs

While synchronizing Unit-5 with

grid, BBP of 220kV Bus-1

operated which resulted in de-

energization of 220kV Bus-1. This

resulted in tripping of running Unit-

1&Unit-3, 220kV lines Pulivedula-

1, Yeralaguntla-1, Chinakampalli-

1, Timmapura

In view of the availability of 25AX,

APGENCO shall keep synchronizing facility in

auto-mode after getting it’s operation verified

by its OEM, M/s BHEL.

APGENCO Yet to be informed Pending

49/III/4 Tripping of

400kV

Krishnapatna

m-Chittoor

line-1

19-10-2015

at 07:49 hrs

R-phase to earth fault had occurred

in line. Chittoor end tried for auto-

reclose. However, due to persistent

fault, breaker at Chittoor end

tripped. Krishnapatnam end relay

did not try for auto-reclose and

gave a 3 phase trip as observed

from D.R

• APGENCO to make A/R functional on all

lines emanating from Krishnapatnam TPS by

10th December, 2015.

APGENCO Yet to be informed Pending


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

TSTRANSC

O

TSTRANSCO informed vide their mail dated 24.06.15 that the

existing relays would be replaced with numerical relays in DPR

works.

Pending

Telangana

Annexure-II

Page 2 of 24

48/II/5 Tripping of

400kV

Nagarjunsaga

r-

Mahboobnaga

r line

07-09-2015

at 2:58 hrs

Line tripped on operation of OV

protection at Mahboobnagar and

DT 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

TSTRANSCO to furnish a detailed report on

the tripping event along with remedial

measures taken to PCSC forum.

TSTRANSC

O



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

• TSTRANSCO to furnish a detailed report on

the tripping event along with remedial


TSTRANSC

O


47/I/1

(GD)

Disturbance

in Srisailam

left bank

power station

18-08-2015

at 15:25 hrs

PendingYet to be informedTSGENCO1. 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 sec possibly 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

PendingYet to be informedTSGENCO1. 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).

Tripping of

400kV

Khammam-

KTPS line-2

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.

47/II/6

Annexure-II

Page 3 of 24

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.


Timer relays have been received at site. A letter has been addressed to

M/s Alstom to complete the work on priority basis.


Commissioning of Autorecloser planned on 14, 15 & 16th of Dec-

2015 subject to availability of LC.

Pending

Karnataka30/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 21-10-2015 and 23-11-2015:

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.

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.

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 21-10-2015:

NIT floated on 5.5.15 through e-portal. Bid evaluation completed.

LOA's issued to M/s Schneider Electric Infrastructure Ltd. on

08.10.2015.


LOA's issued to M/s Schneider Electric Infrastructure Ltd. on

08.10.2015. Engineering work is in progress.

Pending

Pending

Annexure-II

Page 4 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

34/I/6 400/220 kV

ICT-1 & 2 at

MUNIRABA

D

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 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

Mahalingapur

a 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.

Pending

Annexure-II

Page 5 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

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 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

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 , 21-10-2015 and 23-11-2015:

1. Completed.

2. Completed.

3. Possibility of DC-1 & DC-2 arrangement and splitting of DC will

be reviewed.

Pending41/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

PendingMail 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

Annexure-II

Page 6 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 29-07-2015:


tendering stage.



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.



tendering stage.



Pending

42/II/2 Tripping of

220kV

Chikodi-

Talandage

and

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.


Action is taken for enabling AR for Mudashinge and Talandage lines.

Work is scheduled during first week of August 2015.

Pending



tendering stage.



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

Annexure-II

Page 7 of 24


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 Mail received on 07-09-2015 , 21-10-2015 and 23-11-2015:

Revised relay settings are awaited from KPTCL.

Revised relay settings furnished by KPTCL will be incorporated in co-

ordination with KPTCL shortly.

Pending


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 recieved on 23-11-2015:

Completed at RTPS end.

Pending

44/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 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 , 21-10-2015 and 23-11-2015:

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.

Pending

PendingMail recieved on 23-11-2015:

1) Completed

3) Two bus operation for 220kV buses : In place of existing CT

switching relays, High speed manual heavy duty change over switch

of sufficient current capacity will be retrofitted to all feeders at 220kV

station and same will be operated manually during changeover of

feeder by one bus to the other and this arrangement may facilitate to

put both buses in service. Time required for this retrofit is around

90days . However, this work will be taken up only after retrofitting of

electromagnetic relays with numerical relays for Main-2 protection of

all 220kV lines, for which work is in progress.

KPCL1. 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.

07-06-2015

at 01:35 hrs

Trippings at

220kV

Raichur TPS

46/II/21

Annexure-II

Page 8 of 24


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.


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

Ambewadi-

Ponda line-1

17-08-2015

at 13:20 hrs

Line tripped on a transient fault .

There is no provision for Auto

reclose.

Complete

outage of

220kV

Peenya

Substation in

Karnataka

48/I/2

(GD)

PendingYet to be informedKPTCL KPTCL to revise distance relay settings at

Nelamangala end for 220 kV Nelamangala –

Hebbal - Peenya line – 1 for the effective line

length of 17 km. These new settings can be

appropriately reviewed as and when the tie-

arrangement at Hebbal is done away with.

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.

27-09-2015

at 4:23:17

hrs

PendingYet to be informedKPTCLKPTCL to activate non-directional Over

Current protection with a time delay of 600-

800 msec for Fuse

failure condition at Lingasugur.

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

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.

06-08-2015

at 4:51 hrs

Tripping of

Unit-1&2

along with

400/220kV

ICT-2 at

Raichur TPS

47/II/13

Annexure-II

Page 9 of 24

48/I/3

(GD)

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.

KPTCL to fast-track providing A/R on all 220

kV lines emanating from Ambewadi SS to

prevent Station shut-down on temporary faults.


48/I/4

(GD)

Complete

outage of 220

kV HSR

substation of

Karnataka

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

KPTCL to review distance relay settings at

Naganathpura SS in view of LILO arrangement

at HSR Lay-out.


49/II/15 Trippings at

Raichur TPS

12-11-2015

at 00:30 hrs

Running Unit-4, 5 and Unit-8 and

400kV RTPS-Yeramaras TPS

feeder got tripped due to de-

energization of both 400kV Bus-

1&2 at Raichur TPS

1. KPCL to carry out hot-line washing of RTPS-

connected lines regularly to avoid trippings due

to fog and dust.

2. KPCL may see the feasibility of providing

breaker flashover protection at RTPS, and

implement the same if possible.

KPCL Yet to be informed Pending


400kV

Kaniyambeta-

Kadakola line

28-10-2015at

12:08 hrs

Line tripped on a Y-phase to earth

fault. There is no provision for auto-

reclose

• KPTCL to provide A/R on Kadakola –

Kaniyampeta line at Kadakola end.

KPCL Yet to be informed Pending

Pending1. KPCL to provide A/R on all 220 kV lines

emanating from Nagjheri PH.

2. KPTCL to provide A/R on all 220 kV lines

emanating from Ambewadi SS.

220kV Nagjheri-Ambewadi line-1

tripped at 13:33 hrs due to B phase

to earth fault. Ambewadi was

radially fed from Nagjheri power

station through 220kV Nagjheri-

Ambewadi line-2. Tripping of this

line caused 220kV Bus shut down

at Ambewadi and remaining lines

and transformers were hand tripped

29.10.2015

at 14:34 hrs

Complete

outage of

220kV

Ambewadi

Substation of

KPTCL

49/I/1.3

(GD)

Yet to be informedKPTCL

Annexure-II

Page 10 of 24

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 BBP Zone 1 & 2 Operated

at Alamathy substation. All the

230KV feeders, 230KV BC, ICT-3,

4 & 5 LV breakers got tripped.

TANTRANSCO to furnish a detailed tripping

report including reasons for delayed clearance

of fault at Almathy.

TANTRANS

CO

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

48/I/1

(GD)

Disturbance

in 220kV

Tamilnadu

system

05-09-2015

at 14:04 hrs

Complete outage of 230kV

Palladam, 230 kV

Othakalmandapam S/s, 230 kV

Coimbatore S/s, 230 kV Thudialur

and 230 kV Sadayapalayam S/s

TANTRANSCO to take suitable measures like

installing more stub-towers along 230 kV OK

Mandapam – Myvady line to avoid excessive

sag due to over-loading.

TANTRANS

CO


48/II/6 Tripping of

400/220kV

Alamathy

ICT-3,4&5

07-09-2015

at 04:24hrs

Triggering incident was failure of

Y & B phase CT failure in 230kV

Korattur feeder

1. TANTRANSCO to furnish a detailed report

on the tripping event covering the sequence of

events, and the remedial measures taken to

PCSC forum.

2. TANTRANSCO to configure Bus-Bar

protection at Alamathy for instantaneous

operation.

TANTRANS

CO


PendingTANTRANSCO vide their mail dated 24.06.15 informed that

different relays in Main-I & Main-II would be ensured at the earliest.


Different relays in Main-I & Main-II will be ensured.

TANTRANS

CO

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.

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.

29-03-2015

at

15:29 hrs

Tripping of

400kV

Alamathy-

SVChatram

line-1&2

and

400/230kV

ICT

at

S.V.Chatram

43/II/5

Tamil Nadu

Annexure-II

Page 11 of 24

49/II/3 Tripping of

220kV

Edamon-

Tirunelveli

line-1&2

12-10-2015

at 21:30 hrs

220kV Edamon-Tirunelveli lines -

1&2 got tripped due to operation of

Bus Bar protection which was due

to human error

KSEB to furnish reasons for DT not being

sent to the remote end during the tripping event

along with remedial measures taken to PCSC

forum.

KSEB Yet to be informed Pending


220kV

Sabarigiri-

Theni line

09-10-2015

at 16:56 hrs

Line tripped on a R-phase to earth

fault. At Sabarigiri, relay gave a 3

phase trip after 220ms. From Theni

end D.R, auto reclose block was

observed.

KSEB to furnish a report on the tripping

incident along with the remedial measures

taken to PCSC forum.

KSEB Yet to be informed Pending

PendingYet to be informedTANTRANS

CO

1. TANTRANSCO to ensure correctness of

operation of LBB relays at SP Koil.

2. TANTRANSCO & MAPS to furnish their

respective compliance report of the

recommendations of to-be-conducted PSAG-14

meeting at MAPS, Kalapakkam.

Fault had occurred in 230kV

MAPS-S.P.Koil feeder-1. LBB

protection got operated as breaker

of this feeder was under lockout

and resulted in tripping of 230kV

bus at S.P.Koil. Unit-1&2 at

MAPS due to loss of evacuating

feeders i.e. 230kV MAPS-S.P.Koil

feeder-1&2

09-11-2015at

09:33 hrs

Complete

outage of

S.P.Koil

station of

TANTRANS

CO and

generation

loss at

Madras

Atomic

Power

station(MAP

S)

49/I/1.5

(GD)

KeralaMail recieved on 30-10-2015:

1. Purchase procedures is still in progress.

2. Replaced.

3. PLCC equipment Tested and found OK.

Pending

(Recomm

endation

No.1)

44/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.

KSEB

Annexure-II

Page 12 of 24


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 25-11-2015:

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 Nov'15 end.

Pending


HVDC pole-

1&2

at Gazuwaka

and 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

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.


Being pursued with POWERGRID, WR-1

Pending

Pending42/II/7 Yet to be informedPGCILPGCIL (SR-II) to submit the report of M/s

ABB’s on preventing supply card failures.

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.

23-02-2015

at

13:34 hrs

Tripping of

400kV

Jeypore-

Gazuwaka

line-

1&2 and

tripping of

HVDC back

to back pole-

1&2 at

Gazuwaka

Annexure-II

Page 13 of 24


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.


Tertiary Transformer charged and auxiliary power for HVDC is being

availed from tertiary widings of ICT.

Pending

Annexure-II

Page 14 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

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

PendingYet to be informedPGCILPGCIL (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

Ramagundam-

Hyderabad

line-3,

400kV

Hyderabad-

Malkaram

line-1 and

400kV Bus-1

at Hyderabad

44/II/4

Multiple

tripping at

Vemagiri

substation of

APTRANSC

O

44/II/6 PendingYet to be informedPGCIL1. 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.

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.

25-04-2015

at 10:04

hrs

Annexure-II

Page 15 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.


44/II/8 Tripping of

400kV

Gooty-NPS

line-2

26-04-2015

at 13:16

hrs


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.



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.


PendingYet to be informedPGCILTo 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).

Lines tripped on transient fault.

Auto reclose was un-successful. SR

&NEW grid separated due to

tripping of 765kV lines

03-05-2015

at 4:13 hrs

Tripping of

765kV

Raichur-

Solapur line-

1&2

45/II/15

Annexure-II

Page 16 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.


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.


Tripping of

HVDC

Talcher-Kolar

Pole-2.

45/II/29

PendingYet to be informedPGCIL1. PGCIL (SR-I) to furnish a report detailing

the sequence of events including the remedial


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.

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.

01-07-2015

at 09:59 hrs

Tripping of

400kV Gooty-

NPS line-1

46/II/13


Major Shut Down of HVDC Bi-pole line for replacement of insulators

in Polluted Streched is planned from 07th 11th January-16 scheduled.

PGCILTo 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).

DC line fault26-05-2015

at 17.55 hrs

Annexure-II

Page 17 of 24


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.


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

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 OV stg-

1 protection at Raichur end on

04.09.2015 at 19:24 Hrs

49/II/4 Tripping of

400kV Gooty-

NPS line-1

13-10-2015at

10:15 hrs

DT was sent to NPS end of line-1

during opening of Main CB of

Gooty-NPS line-2 at Gooty end.

This resulted in tripping of line-1

at NPS and line was holding from

Gooty. OV protection got operated

at NPS end and resulted in tripping

of line

1. PGCIL (SR-I) to configure time scale

resolution in Event Logger to msec. at Nelllore

PS (NPS) and furnish DR corresponding to

OVR, Stag-I operation at NPS end during the

tripping event.

2. PGCIL (SR-I) to ensure time-sync of DR’s

and EL’s with GPS at Gooty & NPS.


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.


46/II/22 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


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.

28-07-2015

at 11.52.22

hrs.

Separation of

SR-grid and

NEW-grid

Annexure-II

Page 18 of 24


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


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

46/II/3 Tripping of

400kV

Ramagundam-

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 OV alongside checking the drop off-

to- pick-up ratio of the OV relay.

2. The tripping is not as per the grading

adopted for OV, 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


400kV

Vemagiri –

GVK (JPD)

line-2

16-07-2015

at 17:02 hrs


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


400 kV

Hassan -

Udupi line-1

05-10-2015

at 13:33

Line tripped due to B-E fault in Z2.

Main 1 relay tripped in Z2. 3 phase

trip operated at Hassan. AR

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

UPCL to furnish reasons for delayed operation

of distance relay in Zone-1 at their end, and the

remedial measures taken, if any.

UPCL Mail recieved on 19-11-2015 (UPCL):

The fault was of resistive nature, was sensed from Hassan end in Zone-

2 reach. The DR from UPCL indicates resistive high current prior to

operation of Zone-1 in C Phase. This is seen as development of Zero

sequence voltage and current prior to Zone -1 operation.

The operation of single phase Z1 from UPCL end was correct

followed by successful AR operation.

Pending

Others

Annexure-II

Page 19 of 24

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


38/II/5 400kV

Ramagundam-

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

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/

TSTRANSC

O

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-II

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.


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 B/U 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 and 25-11-2015:

All the relay settings were checked and found ok

Pending

with

PED.

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 and 25-11-2015:

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

with

CEPL

Annexure-II

Page 21 of 24

43/II/12 Multiple

tripping at

400kV

Raichur(PG)

and RTPS 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/KPTC

L/ PGCIL(SR-

I)


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

Tripping of

Unit-8 at

RTPS

24-05-2015

at 19:19 hrs

Tripped on Overvoltage.

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


2. KPCL to check the excitation system of Unit

8 of RTPS, and submit the remedial measures


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

with

KPCL,

APGEN

CO

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/TSTR

ANSCO/PGC

IL (SR-I)

Annexure-II

Page 22 of 24

Complete

outage of

Krishnapatna

m TPS

47/I/2

(GD)

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

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.

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

20-05-2015

at 20:38 hrs

Complete

outage of

MEPL power

station

45/I/2

(GD)

Tripping of

220kV Kadra-

Karwar line-

1&2 and

220kV

Kaiga-Kadra

line

47/II/7 PendingYet to be informedKPTCL/

KPCL/

NPCIL

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.

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.

31-07-2015

at

11:44 hrs

PendingYet to be informedAPGENCO/

PGCIL (SR-

I)

1. APGENCO to furnish to PCSC forum (i) A3-

size SLD 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 EL.

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.

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

08-09-2015

at 18:20 hrs

Annexure-II

Page 23 of 24


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.

TSGENCO/ APTRANSCO to carry-out PLCC

end-to-end testing in co-ordination with

APTRANSCO/ TSGENCO to sort out

reception of signals on 400 kV Kurnool –

Srisailam line.

TSGENCO/

APTRANSC

O



400/220 kV

ICT-2 at

Kurnool

Substation

and 400kV

Kurnool-

Srisailam line

26-10-2015

at 14:31 hrs

400kV Kurnool-Srisailam line -

distance protection zone-2 had

operated at Srisailam end.

However from DR, R-phase to

earth fault and zone-2 start were

observed. Breakers at Kurnool end

tripped on direct trip receive from

Srisailam end.

ICT-2 Main-CB tripped due to

operation of bus bar protection,

and Tie-CB tripped due to DT

receipt from Srisailam

1.TSGENCO in coordination with

APTRANSCO to carry out end-to-end testing

of PLCC channels by 15.12.2015 on 400 kV

Srisailam – Kurnool S/C line and 400 kV

Srisailam – Sattenapalli D/C line.

2. TSGENCO and APTRANSCO to make A/R

functional on 400 kV Srisailam – Kurnool line.

3. TSGENCO to resolve configuration

problems with the newly commissioned relays

at Srisailam LB so that unwarranted DT

sending to remote ends is addressed.

TSGENCO/

APTRANSC

O


Tripping of

220kV Kadra-

Karwar line-

1&2 and

220kV

Kaiga-Kadra

line

47/II/7

PendingYet to be informedNTPL/ CEPL1. 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.


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.

Tripping of

400kV

Coastal-

NTPL line

and running

units

at NTPL

47/II/9 03-08-2015

at

15:43 hrs

PendingYet to be informedKPTCL/

KPCL/

NPCIL

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.

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.

31-07-2015

at

11:44 hrs

Annexure-II

Page 24 of 24

Sl.No. Element NameOutage

date/time

Revival

date/time

Reason for

OutageSender/ Receiver

Remedial Measures/ Actions

taken

1400 Kv KRISHNAPATNAM -

NELLORE

20-07-

2015/11:27:00

20-07-

2015/12:00:00

BUS -1

TRIPPED :

REASON

AWAITED

APGENCO/

APTRANSCO

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):

2 220 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

3 220 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

Pending Remedial Measures/ Actions taken

for the Critical Tripping Incidents (as on 14-12-2015)

Annexure-III

Page 1 of 8

4 400 Kv NCTPS - SVCTM-I05-10-

2015/14:31:00

05-10-

2015/15:44:00

TRIPPED ON R-

PH FAULT

TANGEDCO/

TANTRANSCO

TANTRANSCO: Temporary

fault. AR lockout at both ends.

Feeder normalised at 15:43 hrs. on

05.10.2015.

TANGEDCO:

5 400 Kv VTPS - MALKARAM 112-10-

2015/11:40:00

12-10-

2015/16:01:00

TRIPPED ON B-

PH FAULT

APGENCO/

TSTRANSCOTo-be-discussed

6 400 Kv VTPS - MALKARAM 113-10-

2015/12:55:00B-N FAULT

APGENCO/

TSTRANSCOTo-be-discussed

7 400/220 kV ICT-1 AT BTPS30-10-

2015/21:02:00

30-10-

2015/22:42:00TRIPPED KPCL To-be-discussed

8400 Kv GAJWEL - SHANKARPALLY

1

02-11-

2015/11:33:00

02-11-

2015/11:59:00R-N FAULT TSTRANSCO To-be-discussed

9400 Kv GAJWEL - SHANKARPALLY

1

02-11-

2015/12:22:00

02-11-

2015/14:40:00R - N FAULT TSTRANSCO To-be-discussed

10 400/220 kV ICT-2 AT KAIGA03-11-

2015/08:26:00

03-11-

2015/09:49:00

TRIPPED ON

DIFFERENTIA

L

PROTECTION

KAPS To-be-discussed

11 400/110 kV ICT-3 AT SALEM10-11-

2015/03:49:00

10-11-

2015/05:04:00

DUE TO OVER

FLUX RELAY

ACTED

TANTRANSCO

TANTRANSCO:

Due to raise in 400 KV grid

voltage, Over fluxing relay

operated. The Frequency variation

from 49.90 Hz to 50.09 Hz was

recorded during the tripping of all

ICTs.

Annexure-III

Page 2 of 8

12 400/230 kV ICT-1 AT SALEM10-11-

2015/03:53:00

10-11-

2015/04:49:00

DUE TO OVER

FLUX RELAY

ACTED

TANTRANSCO

TANTRANSCO:






ICTs.

13 400/230 kV ICT-2 AT SALEM10-11-

2015/03:51:00

10-11-

2015/04:57:00

DUE TO OVER

FLUX RELAY

ACTED

PGCIL (SR-II)/

TANTRANSCO

TANTRANSCO:






ICTs.

PGCIL (SR-II):

14 400/110 kV ICT-4 AT SALEM10-11-

2015/02:29:00

10-11-

2015/07:17:00

TRIPPED DUE

TO OVER

FLUX

TANTRANSCO

TANTRANSCO:






ICTs.

15 400/230 kV ICT-4 AT SALEM11-11-

2015/04:42:00

11-11-

2015/17:58:00

TRIPPED DUE

TO OVER

FLUX

PGCIL (SR-II)/

TANTRANSCO

TANTRANSCO:



operated. Carried out the

maintenance work and the

overfluxing relay was tested and

healthiness was ensured.

PGCIL (SR-II):

Annexure-III

Page 3 of 8

16 400 kV KAIGA - GUTTUR 213-11-

2015/18:21:00

TRIPPED ON R-

PH FAULTKAPS/ KPTCL

PGCIL-SR2:

Portion of the line in which fault

occured owned and maintained by

M/s KPTCL. May be clarified

from M/s KPTCL

KPTCL:

KAPS:


2015/22:04:00

DISTANCE

PROTECTIONKAPS/ KPTCL To-be-discussed


2015/17:24:00

16-11-

2015/18:28:00Y -N FAULT

TANGEDCO/

TANTRANSCO

TANTRANSCO: Temporary

fault. Feeder normalised at 18:28

hrs. on 16.11.2015.

TANGEDCO:

19 220 kV CHITTOR - THIRUVALEM18-11-

2015/11:20:00

18-11-

2015/16:18:00

BUSBAR

PROTECTION

OPERATED @

CTR END

APTRANSCO/ TNEB

TANTRANSCO:

There was no tripping of 230kV

Thiruvalam – Chitoor feeder on

18.11.2015 at Thiruvalam end.

APTRANSCO:

20400 Kv KRISHNAPATNAM -

CHITTOOR

21-11-

2015/07:18:00CB PROBLEM

APGENCO/

APTRANSCOTo-be-discussed


2015/13:15:00

23-11-

2015/19:39:00

DISTANCE

PROTECTIONKAPS/ KPTCL To-be-discussed

Annexure-III

Page 4 of 8

22 400 Kv HASSAN - UPCL 223-11-

2015/12:53:00

23-11-

2015/13:14:00

B-PH ZONE-1

DISTANCE

PROTECTION

OPERATED

PGCIL-SR2/ KPTCL/

UPCLTo-be-discussed


2015/15:07:00

27-11-

2015/16:11:00R-G FAULT KAPS / KPTCL To-be-discussed

24 400/220 kV ICT-2 AT BANGALORE27-11-

2015/18:47:00

27-11-

2015/19:26:00

BUS BAR

PROTECTION

ACTED

PGCIL (SR-II) To-be-discussed

25 400/230 kV ICT-3 AT UDUMALPET27-11-

2015/11:25:00

27-11-

2015/11:34:00

TRIPPED ON

MAL

OPERATION


26 400/230 kV ICT-3 AT UDUMALPET27-11-

2015/17:25:00

27-11-

2015/18:38:00

RELAY

MALOPERATI

ON


27 400 Kv ALM - SVCTM-II27-11-

2015/15:40:00

27-11-

2015/16:37:00C -G FAULT TANTRANSCO

TANTRANSCO: 400kV

S.V.Chatram - Alamathy -1 feeder

'C' phase jumper got cut at

Loc.No.178 from Alamathy end

and created temporary fault with

400kV S.V.Chatram - Alamathy -

2 feeder 'A' phase jumper. Both

feeders runs on the same tower.

PUTT Trip and AR successful at

S.V.Chatram end. AR lockout at

Alamathy end.

28 220 kV KANIAMPET - KADAKOLA27-11-

2015/09:55:00

TRIPPED ON

DISTANCE

PROTN

KSEB / KPTCL To-be-discussed

Annexure-III

Page 5 of 8

29 400 Kv ALM - SVCTM-I27-11-

2015/15:40:00

SWITCH ON

TRANSIENT

FAULT

TANTRANSCO

TANTRANSCO: AR lockout at

both ends. C-Phase jumper cut at

LOC.NO.178 from Alamathy SS

end was attended. Feeder

normalised on 10.12.2015 at

12:45hrs.

30 400/220 kV ICT-1 AT BANGALORE27-11-

2015/18:47:00

27-11-

2015/19:15:00

BUS BAR

PROTECTION

ACTED



2015/14:09:00

28-11-

2015/16:20:00B-N FAULT KAPS / KPTCL To-be-discussed


2015/01:04:00

TRIPPED ON R-

N FAULTKAPS / KPTCL To-be-discussed


2015/01:04:00

TRIPPED ON R-

N FAULTKAPS / KPTCL To-be-discussed

34400 kV DICHIPALLY -

RAMAGUNDAM

02-12-

2015/02:46:00

02-12-

2015/04:13:00B-N FAULT TSTRANSCO / NTPC To-be-discussed

35400 kV DICHIPALLY -

RAMAGUNDAM

02-12-

2015/12:40:00

TRIPPED ON B-

Y FAULTTSTRANSCO / NTPC To-be-discussed

36400 kV TALAGUPPA -

NEELAMANGALA

03-12-

2015/16:20:00

TRIPPED ON

LINE FAULTKPTCL To-be-discussed


2015/03:54:00

04-12-

2015/04:58:00

TRIPPED ON B-

PH FAULT

TANGEDCO /

TANTRANSCO

TANTRANSCO/TANGEDCO:

Temporary fault. AR lockout at

both ends. No visible fault and

feeder normalised on 04.12.2015

at 04:58 hrs.

TANGEDCO:

Annexure-III

Page 6 of 8

38 400 Kv HASSAN - UPCL 106-12-

2015/10:40:00

06-12-

2015/10:56:00

TRIPPED ON R-

N FAULTPGCIL (SR-II) / UPCL To-be-discussed

39400 kV NEYVELI TS 2 - NEYVELI

TS2 EXP

06-12-

2015/20:35:00

06-12-

2015/23:03:00DT RECEIVED NLC To-be-discussed

40400 kV NEYVELI TS2- NEYVELI TS-

I

06-12-

2015/23:12:00

07-12-

2015/00:46:00

MALOPERATI

ONNLC To-be-discussed

41 400/220 kV ICT-3 AT TRICHUR06-12-

2015/13:50:00

06-12-

2015/21:38:00

REF

OPERATEDKSEB To-be-discussed

42 400 Kv NPS - TPCIL 210-12-

2015/03:48:00

10-12-

2015/04:56:00

RELAY

MALOPERATI

ON AT TPCIL

END

To-be-discussed

43400 Kv VIJAYAWADA - NELLORE -

AP -

10-12-

2015/10:51:00

10-12-

2015/11:46:00

TRIPPED DUE

TOBACKIP

IMPEDANCE

RELAY ACTED

To-be-discussed

44 400 kV KALPAKKA - VEMAGIRI 210-12-

2015/15:20:00

10-12-

2015/16:20:00

BUS BAR

PROTECTION

OPERATED @

KLPAKA

To-be-discussed

45 400 kV SIMHADRI - KALPAKKA 410-12-

2015/15:20:00

10-12-

2015/16:30:00

BUS BAR

PROTECTION

OPERATED @

KLPAKA

To-be-discussed

46 400/220 kV ICT-2 AT CHITTOOR11-12-

2015/07:12:00

11-12-

2015/16:23:00

BUCHOLZ

RELAY

OPERATION

To-be-discussed

Annexure-III

Page 7 of 8

47400 kV TRIVENDRUM -

TIRUNELVELI 1

11-12-

2015/04:56:00B-N FAULT To-be-discussed

48400 KV ALAMATHI -

THIRUVALLAM-1

13-12-

2015/22:42:00

Y-PH LA

BLAST @

THVLM END

To-be-discussed

49 400 kV ALAMATHI - VALLUR 213-12-

2015/22:42:00

Y-PH LA

BLAST @

THVLM END

To-be-discussed

Annexure-III

Page 8 of 8

SOUTHERN REGIONAL POWER COMMITTEE

BENGALURU

Additional Agenda for the 50

th Meeting of Protection Coordination Sub-

Committee of SRPC to be held on 27.01.2016 (Wednesday)

1. Grid Occurrences

1.1 Additional 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 period December, 2015 given at Annexure-IV would be

discussed in the PCSC meeting

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 of the tripping events

pertaining to their system.

1.2 In compliance of Regulations 5.2 (r) of IEGC, the Constituents are required to

furnish the following information in respect of Grid Occurrences:

(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 has been brought to Constituents attention vide SRPC letter

letter No. SRPC/ SE-III/ PCSC-50/ 2015/ 9091- 123 dated 18-12-2015. The non-

compliance in this regard would be discussed in the meeting.

*****

1. ग्रिडडडस्टर्बन्स / ग्रिडइन्सडन्टकावििरण - Details of Grid Disturbances:

Sr. No.

क्र.स.ं

घटनाकावििरण /

Details of Event

तारीख/ Date

&

समय /Time

कारण / Reason टटप्पणी /Remarks


1

Complete outage of

TPCIL power station 30-12-2015 at

06:02hrs Running units at Thermal Power

tech power Station tripped due to

tripping of 400kV Nellore pooling

station (NPS)-TPCIL line and

400kV Nellore pooling station

(NPS)-NCC line

Gen loss : 1270 MW

GD-1

2.

Complete outage of

230kV Mywadi

station of

TANTRANSCO

21-12-2015 at

6:28 hrs Busbar protection got operated for a

fault in 230kV Mywadi-Anaikadavu

line

0

GD-1

2. डडडस्टर्बन्स / ग्रिडइन्सडन्टकावििरण - Details of Grid incidents:

Sr. No.

क्र.

स.ं

घटनाकावििरण /

Details of Event

तारीख/ Date

&

समय /Time

कारण / Reason टटप्पणी /Remarks


1 Tripping of HVDC Bhadrawati Pole-2

06-12-2015 at 07:09 hrs

HVDC pole-2 tripped due to problem

in convertor transformer GI-2

2

Tripping of

400/220kV ICT-3 at

Madakathara

substation

06-12-2015 at

13:50 hrs

B-phase to earth fault had occurred in

220kV Shoranur-Madakathara line

due to snapping of earth wire. ICT-3

at Madakathara tripped on operation

of differential and REF protection for

this through fault.

3 Tripping of 400kV

Vijayawada-

Nellore(AP) line-3 10-12-2015 at

10:51 hrs

Operation of reactor Backup

Impedance protection resulted in

tripping of line. Direct trip was sent

to Nellore (AP)

3. Lines tripping due to tripping at one end/PLCC mal-operation

Sr. No.

क्र.

सं.


of Event





1

Tripping of 400 kV

Neyveli TS2-

Neyveli TS-I (EXP)

and

06-12-2015

at 23:12 hrs lines tripped due to suspected

mal-operation of PLCC

2

Tripping of 400 kV

Neyveli TS 2 -

Neyveli TS2 EXP

06-12-2015

at 20:35 hrs

lines tripped due to suspected

mal-operation of PLCC

3 Tripping of 400kV

NPS-TPCIL line-2

10-12-2015at

3:48 hrs

line tripped due to mal-operation

of PLCC and direct trip was

received at TPCIL end

Annexure-IV

tangedco, ped, ntpc (kayamkulam), maps, ntecl, ntpl, sel, cepl & mepl. 5. network configuration...

Documents