Download shutdown on kalpaka-simhadri both circuits

SHUTDOWN ON NUNNANELLORE BOTH CIRCUITS
STUDY RESULTS AND
PROPOSED ACTION PLAN
HIGHLIGHTS OF THE
SHUTDOWN
• 400 KV D/C NUNNA-NELLORESRIPERUMBUDUR LINE IS A VITAL LINK
• TYPICAL FLOW IS IN THE ORDER OF 330-380
MW EACH
• OUTAGE OF BOTH CIRCUITS IN PRESENT
CONDITION WOULD MEAN INCREASED
LOADINGS ON OTHER 400 KV NETWORK
LINES IN AP AS WELL AS OVERLOADING
THE 220 KV NETWORK OF APTRANSCO
• LARGE VOLTAGE DIPS WOULD ALSO
OCCUR IN CUDDAPAH, GOOTY, BANGALORE
AND MADRAS
BASE CASE
AFTER LC
PREVENTATIVE ACTIONS
• REDUCTION OF GENERATION IN VTS/LANCO BY 350-400 MW
• REDUCED GENERATION IN SILERU BASIN AND SRISAILAM
COMPLEX
• STRICTLY NO OVERDRAWALS BY TN-KERALA AND
KARNATAKA AND UNDERDRAWALS BY AP
• NO LOAD CHANGE-OVERS IN AP DURING THE SHUTDOWN
• IMPORT AT GAZUWAKA WILL BE MINIMISED
• REGULATE GENERATION AT SIMHADRI ,COASTAL GAS IN
CASE OF OVERLOADING OF CDP-MDS LINE.
• IMPROVE VOLTAGES AT CUDDAPAH, GOOTY, BANGALORE
AND MADRAS : BUS REACTORS TO BE TAKEN OUT IN
ADVANCE
• INCREASED FILTER COMMITMENT AT KOLAR
• NO OTHER LC TO BE TAKEN IN THIS PERIOD ESPECIALLY OF
VTS EVACUATION LINES – IF INEVITABLE LC ‘S MAY BE
STAGGERED SO THAT NETWORK IS NOT SEVERELY
DEFORMED
PLANNING FOR OUTAGE
• INITIALLY AT THE TIME OF SHUT-DOWN, VTS/LANCO TO BE
REDUCED BY AROUND 400 MW
• MINIMISE GENERATION AT SILERU BASIN
• REDUCTION IN GENERATION AT SIMHADRI, COASTAL GAS IF
FLOW ON THE LINES ARE NOT BELOW 200 MW EACH
• NO LOAD CHANGE OVERS FOR THE PERIOD OF SHUT DOWN
IN N.COASTAL AP
• FREQUENCY TO BE MAINTAINED AT 49.8 HZ AND ABOVE
• MORE HYDRO MACHINES TO BE ON BARS AS RESERVE
• ALL UNITS > 50 MW TO BE ON FGMO
• DF/DT AND U/F RELAYS TO BE IN SERVICE
• KOLAR INTER-TRIP SCHEME TO BE IN SERVICE
• ER RUN-BACK SCHEME TO BE IN SERVICE
• NELLORE LINES CAN BE IDLE-CHARGED FROM MADRAS FOR
VOLTAGE SUPPORT
CONTINGENCY PLAN
CONTINGENCY:-TRIPPING OF 400 KV CUDDAPAH-MADRAS DURING LC
• EFFECT:– LARGE VOLTAGE DIP OF MORE THAN 15 KV AT CUDDAPAH,
BANGALORE AND MADRAS:- NELLORE LINE CAN BE IDLECHARGED FROM MADRAS
– 400 KV CUDDAPAH-KOLAR LINE LOADING GOES ABOVE 700 MW.
– POSSIBLE SEPARATION OF AP-KARNATAKA FROM TN-KERALA
GRID .
• REMEDIAL ACTION:– IMMEDIATE REDUCTION IN VTS/LANCO GENERATION BY
FURTHER 400MW OR BETTER STILL FORCING TWO UNITS ON
HOUSE LOAD
– REDUCTION IN GENERATION BY SIMHADRI AND COASTAL GAS
STATIONS TO REDUCE LOADING ON CDP-KOLAR TO AROUND
450-500 MW
– LOAD SHEDDING BY TN-KERALA
– EXPORT TO ER/WR IF POSSIBLE
– INCREASED IMPORT AT KOLAR
– REDUCTION IN RAMAGUNDAM GENERATION AS EMERGENCY
MEASURE
CONTINGENCY
CASE
CONTINGENCY PLAN
CONTINGENCY:-TRIPPING OF 400 KV CUDDAPAH-KOLAR
DURING LC
•
•
EFFECT:– LARGE VOLTAGE DIP OF MORE THAN 15 KV AT CUDDAPAH,
BANGALORE AND MADRAS:-NELLORE LINE CAN BE IDLECHARGED FROM MADRAS
– 400 KV CUDDAPAH-MADRAS LINE LOADING GOES ABOVE 700
MW.
– POSSIBLE SEPARATION OF AP-KARNATAKA FROM TN-KERALA
GRID .
REMEDIAL ACTION:– IMMEDIATE REDUCTION IN VTS/LANCO GENERATION BY
FURTHER 400MW OR BETTER STILL FORCING TWO UNITS ON
HOUSE LOAD
– REDUCTION IN GENERATION BY SIMHADRI AND COASTAL GAS
STATIONS TO REDUCE LOADING ON CDP-MADRAS TO AROUND
450-500 MW
– LOAD SHEDDING BY TN-KERALA
– EXPORT TO ER/WR IF POSSIBLE
– INCREASED IMPORT AT KOLAR
– REDUCTION IN RAMAGUNDAM GENERATION AS EMERGENCY
CONTINGENCY
MEASURE
CASE
CONTINGENCY PLAN(CONTD)
CONTINGENCY:- TRIPPING OF ONE LINE OF TALCHER-KOLAR
REMAINING POLE ON GR MODE
•
EFFECT:–
–
–
–
–
–
•
FLOW WILL BE REDUCED TO 500 MW
LOSS OF 800-900 MW
RUN-BACK AT TALCHER WOULD ACT
SR INTER-TRIP SCHEME WOULD ACT
FREQ DIP OF AROUND 1 HZ EXPECTED IN SR GRID
DF/DT AND UFR TO BE IN SERVICE
REMEDIAL ACTION:–
–
–
–
FREQUENCY SHOULD BE MANTAINED 49.8 Hz AND ABOVE
ALL GENERATORS 50MW AND ABOVE SHOULD BE ON FGMO
IMMEDIATE REDUCTION IN VTS/LANCO GENERATION BY 250-300 MW
REDUCTION IN GENERATION BY SIMHADRI AND COASTAL GAS STATIONS
TO REDUCE LOADINGS ON CDP-KOLAR, CDP-MADRAS AND GTY-HOODY
– LOAD SHEDDING BY TN-KERALA AND KARNATAKA
– EXPORT TO ER/WR IF POSSIBLE
– REDUCTION IN RAMAGUNDAM GENERATION AS EMERGENCY MEASURE
CONTINGENCY PLAN(CONTD)
CONTINGENCY:- TRIPPING OF BOTH POLES AT KOLAR
•
•
•
•
•
•
•
EFFECT:LOSS OF 1200-1400 MW
RUN-BACK AT TALCHER WOULD ACT
SR INTER-TRIP SCHEME WOULD ACT
FREQ DIP OF MORE THAN 1.2 HZ EXPECTED IN SR GRID
DF/DT AND UFR TO BE IN SERVICE
REMEDIAL ACTION : IMPORT FROM ER AT GAZUWAKA MAY HAVE TO
BE INCREASED. THIS HAS TO BE DONE DEPENDING ON LOADING OF
CUDDAPAH-KOLAR AND CUDDAPAH-MADRAS LINES
–
–
–
–
FREQUENCY SHOULD BE MANTAINED 49.8 Hz AND ABOVE
ALL GENERATORS 50MW AND ABOVE SHOULD BE ON FGMO
IMMEDIATE REDUCTION IN VTS/LANCO GENERATION BY 300-400 MW
REDUCTION IN GENERATION BY SIMHADRI AND COASTAL GAS STATIONS
TO REDUCE LOADINGS ON CDP-KOLAR, CDP-MADRAS AND GTY-HOODY
– LOAD SHEDDING BY TN-KERALA AND KARNATAKA
– EXPORT TO ER/WR IF POSSIBLE
– REDUCTION IN RAMAGUNDAM GENERATION AS EMERGENCY MEASURE