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

NATIONAL GRID QUICK FACTS 400 MU CONS IN A DAY-1.5% IS 6 MU, 2190 MU IN A YEAR, 2/UNIT IS 4400 MILLION RUPEES IS 440 CRORE RUPEES

REGIONAL GRIDS INSTALLED CAPACITY TOTAL(APPROX) 125,000 MW 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

‘ELECTRICAL’ REGIONS NORTHERN REGION 1 NORTH-EASTERN REGION EASTERN REGION WESTERNREGION TALA PROJECT-LARGE CENTRAL GRID ARUNACHAL TO GUJARAT ON SAME FREQ 2 SOUTHERN REGION WITH THE COMMISSIONING OF THE TALA PROJECT CONNECTING THE EASTERN AND NORTHERN GRIDS, INDIA WILL HAVE ONLY TWO GRIDS

Installed capacity & Inter regional links MW capacity NER-ER 1,850 ER-NR 2,700 ER-SR 1,200 ER-WR 1,650 SR-WR WR-NR 900 Talcher Kolar HVDC Bipole 2,000 Total as on 31.08.06 11,500 Target for 2012 37,500 Two synchronous systems -North-Central & South 34,307 MW 30,500 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

Energy Resource Map Coal Hydro

OVERVIEW OF SOUTHERN REGIONAL GRID

SOUTHERN REGION – GEOGRAPHY ANDHRA PRADESH TAMIL NADU KARNATAKA KERALA 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 TALA PROJECT-LARGE CENTRAL GRID ARUNACHAL TO GUJARAT ON SAME FREQ

GENERATING UNITS IN SOUTHERN REGION UNIT CAPACITY AP KAR KER TN CGS TOTAL THERMAL (500 MW) 2 8 10 THERMAL (200-250 MW) 7 13 15 45 GAS/THERMAL (100-150 MW) 9 3 24 HYDRO (>50 MW) 27 29 16 87 48 38 19 165 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

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

400KV SUB-STATIONS IN SR 8 9 2 19 6 5 1 12 1 22 15 42 AP KAR KER TN   POWERGRID STATE OTHERS TOTAL AP 8 9 2 19 KAR 6 5 1 12 KER TN  1 22 15 42 KALPAKKA RAMAGUNDAM 1 SIMHADRI GAZUWAKA KHAMMAM GMR VEMAGIRI HYDERABAD P P P JEGRUPADU EXTN MAMIDIPALLY MEHA BOOB NAGAR P VIJAYAWADA RAICHUR P NAGARJUNASAGAR MUNIRABAD SRI SAILAM P KURNOOL P GOOTY NARENDRA CUDDAPAH 60 DAVANAGERE P NELLORE KAIGA HIRIYUR CHITTOOR NELAMANGALA ALMATHI TALAGUPPA BANGALORE P KOLAR P MADRAS -- OF POWERGRID MYSORE HOODY HOSUR -- OF NTPC NEYVELI TPS I (EXP) 63 SALEM -- OF ANDHRA PRADESH P NEYVELI -- OF TAMIL NADU UDUMALPET P TRICHY TRICHUR -- OF KARNATAKA P P -- OF NLC P MADURAI -- OF NPC TRIVENDRUM

MONSOONS SOUTH WEST MONSOON NORTH EAST MONSOON BACK

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

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

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

LOAD ANGLE AN EMPIRICAL TOOL

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

STABILITY CLASSIFICATION VLPGO 2005 WG1

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

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

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

LOAD CHANGE OVER BY AP SKEWS LOADING PATTERN

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------------>

Visualization Techniques

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)