LOAD ANGLE MEASUREMENT USING SCADA A UNIQUE VISUALISATION TOOL FOR GRID OPERATION

1. LOAD ANGLE MEASUREMENT USING SCADA A UNIQUE VISUALISATION TOOL FOR GRID OPERATION S.P.KUMAR CM(SCADA-IT) SRLDC, POWER GRID

2. NATIONAL GRIDQUICK FACTS

3. REGIONAL GRIDS INSTALLED CAPACITY NORTHERN :- 33,782 MW EASTERN :- 16,680 MW SOUTHERN :- 37,054 MW WESTERN :- 34,867 MW NORTH-EASTERN :- 2,443 MW TOTAL(APPROX) 125,000 MW NORTHERN REGION NORTH-EASTERN REGION EASTERN REGION WESTERNREGION SOUTHERN REGION

4. ‘ELECTRICAL’ REGIONS NORTHERN REGION 1 NORTH-EASTERN REGION EASTERN REGION WESTERNREGION 2 SOUTHERN REGION WITH THE COMMISSIONING OF THE TALA PROJECT CONNECTING THE EASTERN AND NORTHERN GRIDS, INDIA WILL HAVE ONLY TWO GRIDS

5. Installed capacity & Inter regional links Two synchronous systems -North-Central & South 30,500 MW 34,307 MW 2,404 MW 16,478 MW 16,000 37,140 MW 36,584 MW Installed Generation Capacity Current : 126,994 MW Target for Year 2012 : 200,000 MW Figures as on 31-Aug-2006

6. Hydro Coal Energy Resource Map

7. OVERVIEW OF SOUTHERN REGIONAL GRID

8. ANDHRA PRADESH KARNATAKA TAMIL NADU KERALA SOUTHERN REGION – GEOGRAPHY POPULATION :- 22.5 CRORES ( 22% OF INDIA) AREA :- 651 (‘000 SQ KM)(19% OF INDIA) INSTALLED CAPACITY:- 36,784 MW(29.5%) WEATHER :- South-west monsoon North-east monsoon SEA COAST :- AROUND 4000 KM

9. GENERATING UNITS IN SOUTHERN REGION A.P TYPICAL GENERATOR SPREAD IN SR KAR - HYDRO - THERMAL KER TN GENERATORS ABOVE 1000 MW - GAS / NAPTHA GENERATORS 500 – 1000 MW - NUCLEAR GENERATORS BELOW 500 MW

10. TYPICAL LOAD SPREAD IN SR LOAD 500-1500 MW LOAD 200-500 MW

11. 400KV SUB-STATIONS IN SR KALPAKKA RAMAGUNDAM SIMHADRI 1 GAZUWAKA KHAMMAM GMR VEMAGIRI HYDERABAD P P JEGRUPADU EXTN P MAMIDIPALLY P MEHA BOOB NAGAR VIJAYAWADA RAICHUR NAGARJUNASAGAR P SRI SAILAM MUNIRABAD P KURNOOL P GOOTY CUDDAPAH NARENDRA 60 P NELLORE DAVANAGERE KAIGA HIRIYUR CHITTOOR NELAMANGALA ALMATHI BANGALORE TALAGUPPA MADRAS KOLAR P -- OF POWERGRID P HOODY MYSORE HOSUR -- OF NTPC NEYVELI TPS I (EXP) 63 -- OF ANDHRA PRADESH SALEM P NEYVELI -- OF TAMIL NADU UDUMALPET TRICHY P -- OF KARNATAKA TRICHUR P P -- OF NLC P MADURAI -- OF NPC TRIVENDRUM

12. MONSOONS SOUTH WEST MONSOON NORTH EAST MONSOON BACK

13. SR QUICK FACTS • INSTALLED CAPACITY 37054 MW • THERMAL: HYDRO 67:33 • PEAK DEMAND MET ≈ 23,000 MW • MAX DAILY CONSUMPTION 525 MU

14. 400KV GRID MAP OF SOUTHERN REGION ORISSA TALCHER BHADRAVATI JEYPORE MAHARASHTRA AP SIMHADRI RSTPP KALPAKKA P KHAMMAM GAZUWAKA MMDP HYDERABAD P VEMAGIRI P GMR MAHABOOB NAGAR GVK P VIJAYAWADA N’SAGAR NARENDRA RAICHUR P KAR KURNOOL MUNIRABAD SSLMM P KAIGA GOOTY 1000 MW HVDC BACK TO BACK LINK P N KADAPA P GUTTUR NELLORE 2000 MW HVDC BIPOLE HIRIYUR TALGUPPA NELAMANGALA `HOODY CHITTOOR 500 KV HVDC LINE MADRAS BANGALORE P KOLAR MAPS HOSUR 400 KV LINE POWERGRID 400 KV LINE APTRANSCO SALEM NEYVELI 400 KV LINE KPTCL NEYVELI TPS – 1 (EXP) TN 400 KV LINE OPERATED AT 220 KV UDUMALPET P TRICHY TRICHUR P THERMAL GENERATING STATION MADURAI 400KV SUB-STATION KER NUCLEAR STATION SRLDC, BANGALORE MARCH 2006 THIRUVANANTHAPURAM

16. Grid Performance Number of Grid Disturbances have come down High Transmission System Availability

17. LOAD ANGLE AN EMPIRICAL TOOL

18. POWER SYSTEM STABILITY • ‘Power system stability is the ability of an electric power system, for a given initial operating condition, to regain a state of operating equilibrium after being subjected to a physical disturbance, with most system variables bounded so that practically the entire system remains intact.’ ---------------------------------------VLPGO ’05, WG1

19. STABILITY CLASSIFICATION VLPGO 2005 WG1

20. WHY DO WE NEED A LOAD ANGLE DISPLAY ? • SOUTHERN REGION WAS PLAGUED BY LOW VOLTAGES, HEAVILY LOADED LINES, LOW FREQUENCY PROBLEMS • SKEWED LOADING ON LINES DUE TO LARGE DISTANCES BETWEEN LOAD AND GENERATION • OPERATOR COULD NOT PERCIEVE HOW NEAR TO THE PRECIPE HE WAS • SEPARATIONS/ GRID DISTURBANCES WAS THE ORDER OF THE DAY • INTER AREA OSCILLATIONS WERE NOTICED FREQUENTLY • DECREASING GENERATION/LOAD SHEDDING IN SELECTED PLACES HELPED ALLEVIATE THESE SYMPTOMS • LOAD ANGLE WAS CALCULATED AND STORED • MANY DISTURBANCES WERE ANALYSED AND AN EMPIRICAL LIMIT WAS CONCIEVED • LOAD ANGLE FOR EACH CRITICAL LINE AND CORRIDOR IS DISPLAYED

21. LOAD ANGLE- VISUAL DISPLAY • DATA FROM ALL STATIONS ARE AVAILABLE AT 10 SEC REFRESH RATE • COMPUTATION OF ANGLE IS DONE AT RSCC SERVER • LINE WISE AND CORRIDOR WISE LOAD ANGLE DISPLAY IS GIVEN TO OPERATOR • GENERALLY LIMITED TO 50O FOR CORRIDOR AND 20O FOR SINGLE HOP FOR CRITICAL LINKS

22. 25 350KM line 200KM line 100KM line 20 15 10 5 0 100 200 300 400 500 600 LOADANGLE AND POWERLEVEL RELATION FOR DIFFERENT LINE LENGTHS Load Angle in degrees Power Level in MW

24. LOAD CHANGE OVER BY AP SKEWS LOADING PATTERN

25. LOAD ANGLE OF RGM-NLY DURING A SYSTEM SEPARATION 80.0 SYSTEM SEPARATION POINT 70.0 60.0 50.0 LOAD ANGLE IN DEGREE 40.0 30.0 20.0 10.0 0.0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 HOURS------------>

28. Visualization Techniques

30. Inputs used • Vindhyachal North Bus L-L Voltage. • Angular Separation between Vindhyachal North Bus and West Bus. ( Available through Phase angle transducer having one input through R-Phase North Bus and another through R-Phase West Bus having range only up to 60 degree) • Phasor Voltage difference between Vindhyachal North Bus and West Bus ( Available through voltage transducer having one input through R-Phase North Bus and another through R-Phase West Bus)