UI SUMMARY BOTTLENECKS IN SR GRID RECENT GRID DISTURBANCES MERIT ORDER OCC PRESENTATION FGMO KAR DISTURBANCE REDUCING THE LOSSES IN GRID BUYING AND SELLING UI RATES

BUYING AND SELLING RATES FOR UI  UI – NECESSARY FOR OVERALL ECONOMY (MERIT ORDER)  UI NEEDS CONSTRAINTLESS TRANSMISSION  TRANSMISSION IS CROSS-SUBSIDISING UI  UI USES TRANSMISSION AND CAUSES LOSSES  BILATERALS CAN BE HEDGED USING UI AND CfD  ……………THE SOLUTION SHOULD KEEP THE SIMPLICITY OF UI, EASY TO IMPLEMENT … YET TAKE CARE OF LOSSES AND TR.CHARGES

BUYING AND SELLING RATES FOR UI  INCREMENTAL LOSSES 2*AVG LOSSES ≈ 2*3.5% ≈ 7%  DIFF BETWEEN BUYING AND SELLING UI ≈ 30pS/UNIT  UI TURNOVER IN SR ≈ 5000 MU WOULD COST ≈ 150 CRORES IN UI RESIDUAL  THIS CAN BE SHARED BY TRANSMISSION STAKEHOLDERS  WOULD GIVE SIGNAL FOR TR.AUGMENTATION

REDUCING THE LOSSES IN THE GRID

 LOSSES REDUCED BY % THROUGHOUT THE GRID LOSSES REDUCED BY % THROUGHOUT THE GRID LOSSES REDUCED BY % THROUGHOUT THE GRID  OPTIMISATION AND CO-ORDINATION OF GT AND ICT TAPS –CORRECTIVE ACTION BASED ON  WEEKLY SEM READINGS  PTI (OFF-LINE)  ONLINE EMS STUDIES  THREE HVDC SET POINT OPTIMISATION  REDUCE THE NO. OF LINE OPENINGS –OPENING LINES IMPACTS LOSSES OPENING LINES IMPACTS LOSSESOPENING LINES IMPACTS LOSSES –SWITCHING OFF SHUNT CAPACITORS  SR HAS 7580 MVAR HT CAPACITORS –GENERATORS ON SYNCH CONDENSOR MODE GENERATORS ON SYNCH CONDENSOR MODEGENERATORS ON SYNCH CONDENSOR MODE  EXAMPLE.. IF SHARAVATHY COMPLEX GENERATORS ARE PUT ON CONDENSOR MODE – TALGUPPA VOLTAGE CAN BE CONTROLLED BETTER –BUS REACTOR SWITCHING  HARNESS GENERATORS CAPABILITY HARNESS GENERATORS CAPABILITY HARNESS GENERATORS CAPABILITY  FIELD ASSESSMENT OF GENERATOR CAPABILITY FIELD ASSESSMENT OF GENERATOR CAPABILITY FIELD ASSESSMENT OF GENERATOR CAPABILITY  MOST DORMANT INTER-STATE LINES CLOSED  BETTER VOLTAGE PROFILE BETTER VOLTAGE PROFILE BETTER VOLTAGE PROFILE

MAXIMUM & MINIMUM DRAWAL AUG ENTITLEMENT WITH TAL 1500MW 2000MW MIN DRAWAL AUG 04 TILL NOW AVG DRAWAL AP TN KER PONDY KAR MAX DRAWAL AUG 04 TILL NOW STATE APR-04 MAR-04 FEB-04 AUG-04 OCT-03 DEC-03 AUG-04

BOTTLENECKS IN TRANSMISSION  KAIGA COMPLEX EVACUATION STILL A PROBLEM  KARNATAKA COASTAL GENERATORS NOT FIRMLY ANCHORED  N.COASTAL AP – EVACUATION OF GAS STATIONS  GMR VASAVI EVACUATION – STILL ON 110KV  SRISAILAM SYSTEM – UNDER UTILISATION  SINGLE ICTs AT NUNNA, GAZUWAKA, CUDDAPAH, GOOTY ETC.  EXPEDITING 400 KV STATION AT MYSORE, CHITOOR  EXPEDITING ICT AT NELLORE

VARIABLE COST CURVE

UI DETAILS

APKARKERTNPONDY Total UI exported(-) / Imported(+) in MUs Total amount paid in Crores Rs Average rate of UI in paise/unit SUMMARY OF UI (FROM 01/JAN/03 TO 29/AUG/04)

INTER REGIONAL UI IN SR (FROM 01/01/03 TO 29/08/04)  TOTAL UI TURNOVER : MU  TOTAL UI AMOUNT DISBURSED:- 980 CR  INTER REGIONAL UI: MU (-)191 MU  AVG WEEKLY TRANSACTION:- 59 MU  AVG WEEKLY UI AMT DISBURSED:- 11 CR  AVG RATE OF UI WITH WR IN PS/U –155 –250  AVG RATE OF UI IMPORT FROM ER IN PS/U –144 ER

INTER-REGIONAL EXCHANGES A/C DETAILS TILL 29/08/04 1.SR IMPORTED 334 MU AND EXPORTED 181 MU TO WR. 2.AMOUNT ACCRUED IN SREB – IRE DUE TO DIFF. IN WR A/C = 38.2Crs 3.AMOUNT ACCRUED IN WREB – IRE DUE TO DIFF. IN SR A/C = 23.3Crs 4.AMOUNT DUE TO SR CONSTITUENTS ON 50:50 BASIS = 30.75Crs % DISBURSEMENT

IMPACT OF LINE OPENING ON SR SYSTEM LOSS  On 3 rd /4 th August all the above lines were opened to control over voltage.  The increase in loss would be around 71 MW LINE NAME INCREASE IN LOSS (MW) VIJAYAWADA-SRISAILAM I 4 VIJAYAWADA-NELLORE II 10 N’SAGAR-CUDAPPA II 9 NELLUR-MADRAS II 9 KOLAR-HOODY II 5 KHAMMAM-MAMIDIPALLI II 7 KOLAR-HOSUR I 8 NEYVELI-SALEM II 6 TRICHY-MADURAI II 7

SOUTHERN REGION LOSS * *Source : Report of System Studies conducted for Accessing Shunt Compensation requirement in Southern Region – March 2004 and March by SREB,CEA in co-ordination with the constituents ** Projected figuresYEAR LOAD (MW) LOSS (MW) %LOSS * * * *

GENERATORS ON SYNCH CONDENSOR MODE: ADVANTAGES  IMPROVED SHORT CIRCUIT LEVELS IMPROVED SHORT CIRCUIT LEVELS IMPROVED SHORT CIRCUIT LEVELS  CAN BE CONVERTED TO GENERATOR MODE IN SHORT NOTICE  EXCELLENT REACTIVE SOURCE  REDUCED LOSSES  CONTROL VOLTAGE FLUCTUATIONS

MW MVAR 3 QUADRANT OPERATION

SYNCHRONOUS CONDENSOR OPERATION: IN OPERATION S. No Name of the Generator Unit No Installed capacity (In MW) Remarks 1N'Sagar2100Running 2N'Sagar3100Running 3N'Sagar4100Running 4N'Sagar5100Running 5N'Sagar6100Running 6N'Sagar7100Running 7 SriSailam LBPH 1150Tested Tested Tested Tested Tested 12Iddukki1130Running 13Iddukki2130Running 14Iddukki3130Running

SYNCHRONOUS CONDENSOR OPERATION: POSSIBLE AT 10PEPPARA33SPELTON SL. NO. POWER STATION INSTALLED CAPACITY TYPE OF SCHEME TYPE OF TURBINE 1SHARAVATHI10x SV.PELTON 2JOG4x18+4x12120SV.PELTON 3VARAHI2x115230SV.PELTON 4KUTTIADI3x2575SPELTON 5 KUTTIADI EXTENTION 1x5050 PELTON 6PALLIVASAL3x7.5+3x437.5SPELTON 7SENGULAM4x1248RPELTON 8SABARIGIRI6x50300SPELTON 9IDUKKI3x130+3x130780SPELTON

DISTURBANCE AT NTPC RAMAGUNDAM ON 26/08/04  DURING TESTING OF GENERATOR NEUTRAL END Y –PH CT, THE LBB RELAYS OF UNIT 7 MAIN AND TIE C.B ACTED RESULTING IN BUSBAR TRIPPING  ALL UNITS ON BAR (UNIT 1,2,3,6) AT NTPC TRIPPED.  THE FEEDERS REMAIN INTER-CONNECTED THROUGH TIE BREAKER  THE TIE BREAKEER FOR AUTO 5 AND GHANAPUR CKT3 WAS NOT AVAILABLE, SO THE INTERCONNECTION WAS LOST  AUTO4 AND GHANAPUR CKT4 TRIPPED ON BACK UP O/C PROETECTION  CHANDRAPUR I & II TIE REMAINED CONNECTED WITHOUT POWER FLOW

N’SAGAR-1 N’SAGAR-2 GHANAPUR-1 GHANAPUR-2 ICT-1 ICT-2 ICT-3 GHANPUR MW 57 MW 95 MW BUS DEAD BREAKER OPEN ICT-4 BREAKER NOT IN SERVICE GHANPUR- 3 ICT-5 BUS DEAD 140 MW

RESTORATION AT RAMAGUNDAM DEVICE CLOSED TIME DATE  ICT 4 20:59 26/08/04  N’Sagar 2 22:00 26/08/04  Chandrapur1 22:36 26/08/04 (Charged)  Chandrapur2 22:37 26/08/04 (Charged)  ICT 5 22:51 26/08/04  Ghanapur2 23:11 26/11/04  Unit 1 23:45 26/08/04  Unit2 00:23 27/08/04  Unit3 09:55 27/08/04  Unit6 01:05 27/08/04

LINES UNDER SHUT DOWN 1.AMBEWADI-PONDA II 2.LINGAPUR-GADAG 3.HUBLI-LINGAPUR 4.HUBLI-NARENDRA II 5.SHARAVATHI-TALAGUPPA 6.HUBLI-TALAGUPPA 7.SHARAVATHI-SHIMOGA II 8.GUTTUR-RANIBENNUR DISTURBANCE IN KARNATAKA ON 02/09/04

 PRE-DISTURBANCE CONDITION –IN KARNATAKA SYSTEM 8 NOS OF 220 KV LINES WERE UNDER SHUTDOWN –SHARAVATHI NAGJHERI,KAIGA,VARAHI,KADRA AND KODASHALLI WAS CONNECTED TO THE REST OF THE SYSTEM VIA KAIGA-GUTTUR D/C AND SHARAVATHI –SHIMOGA LINES  AT 14:15 HRS THE CT ON SHARAVATHI – SHIMOGA 4TH CIRCUIT EXPLODED. BOTH BUSES AT SHIMOGA BECAME DEAD.  VARAHI AND MANGALORE ALSO BECAME DEAD BECAUSE OF LOAD – GENERATION MISMATCH.

DISTURBANCE IN KARNATAKA ON 02/09/04  THE ENTIRE POWER FROM HYDRO AND KAIGA WAS BEING EVACUATED THROUGH KAIGA- GUTTUR D/C.  SUBSEQUENTLY LINES KAIGA-GUTTUR D/C AND GUTTUR ICT TRIPPED. THIS CAUSED AN ISLAND OF SHARAVATHI,NAGHJERI,KAIGA WITH AROUND 500 MW LOAD. IN BLOCK SHARAVATHI,NAGHJERI BLOCK FREQUENCY WENT UPTO 50.8 HZ  KAIGA UNITS WENT ON HOUSE LOAD. KAIGA UNIT 1 SURVIVED AND WAS INTEGRATED WITH NAGJHERI BLOCK AT 15:33 HRS. KAIGA UNIT2 GOT POISONED OUT.

RESTORATION  GENARTION AT NAGJHERI WAS REDUCED AND 2 UNITS OF SHARAVATHI WERE SYNCHRONIZED.  GUTTUR-RANIBENNUR WAS CLOSED AND LOADS OF GUTTUR WERE TAKEN UP RADIALLY.THE GENERATION OF THIS BLOCK WAS STABLE AT 650 MW.  SUPPLY WAS EXTENDED TO KAIGA BY CLOSING ONE CIRCUIT OF KAIGA-GUTTUR LINE.  SHIMOGA BUS WAS ENERGIZED FROM PEENYA AND THE ISLAND WAS SYNCHRONIZED WITH REST OF THE GRID BY SYNCHRONIZING 220 KV SHARAVATHI-SHIMOGA CKT 1 AT 16:12 HRS.SUBSEQUENTLY SHARAVATH-SHIMOGA 3 WAS CLOSED.