STATE ESTIMATOR QUALITY TRACKING IN BC Hydro EMS IMPLEMENTATION

1. STATE ESTIMATOR QUALITY TRACKING IN BC Hydro EMS IMPLEMENTATION Dr. DJORDJE ATANACKOVIC, P.Eng. Engineering Team Leader, Power system Applications, Grid Operations Support

2. STATE ESTIMATOR GENERAL PERFORMANCE REQUIREMENTS • CONVERGENCE SUCCESS RATE OF 98% • COST FUNCTION IN THE RANGE OF 8000 – 11000 (~2500 BUSES, 4000 ANALOG MEASUREMENTS) • TOTAL GENERATION ERROR < 40 MW • TOTAL INTERCHANGE ERROR < 10MW • MAX. MW BUS MISMATCH < 50MW • TOTAL LOAD ALLOCATION ERROR < 400MW

3. STATE ESTIMATOR QUALITY MONITORING – NEW INDICES • TOTAL LOAD ALLOCATION ERROR • TOTAL MW, MVAR LINE FLOW RESIDUAL PER MEASUREMENT • TOTAL MW, MVAR INJECTION RESIDUAL PER MEASUREMENT • TOTAL VOLTAGE AND CURRENT RESIDUAL PER MEASUREMENT

4. STATE ESTIMATOR QUALITY MONITORING TOTAL LOAD ALLOCATION ERROR • CALCULATED AS A SUM OF LOAD RESIDUALS FOR ALL LOADS IN BC HYDRO AREA • LOAD RESIDUAL IS A DIFFERENCE BETWEEN ESTIMATED LOAD AND ALLOCATED LOAD • BC HYDRO PERFORMANCE CRITERIA : • TOTAL LOAD ALLOCATION ERROR SHOULD NOT EXCEED 600 MW MAXIMUM • AVERAGE LOAD ALLOCATION ERROR OVER A PERIOD OF ONE YEAR SHOULD NOT EXCEED 400 MW

5. STATE ESTIMATOR QUALITY MONITORING TOTAL MW,MVAR LINE FLOW RESIDUAL PER MEASUREMENT • CALCULATED AS A SUM OF MW/MVAR LINE FLOW RESIDUALS FOR ALL MEASUREMENTS IN THE CONSIDERED ZONE DIVIDED BY NUMBER OF MEASUREMENTS • THREE ZONES ARE USED FOR THIS TRACKING: • TRANSMISSION (230 KV AND ABOVE) • SUBTRANSMISSION (60 – 138KV) • DISTRIBUTION (BELOW 60 KV) • BCTC PERFORMANCE CRITERIA FOR A PERIOD OF ONE YEAR: • TRANSMISSION - BELOW 7 MW • SUBTRANSMISSION - BELOW 15 MW • DISTRIBUTION - BELOW 20 MW

6. STATE ESTIMATOR QUALITY MONITORING TOTAL MW,MVAR INJECTION RESIDUAL PER MEASUREMENT • CALCULATED AS A SUM OF ALL INJECTION RESIDUALS IN A CONSIDERED ZONE DIVIDED BY NUMBER OF MEASUREMENTS IN THE ZONE • BCH PERFORMANCE CRITERIA FOR A PERIOD OF ONE YEAR: • TRANSMISSION – BELOW 3 MW • SUBTRANSMISSION - BELOW 7 MW • DISTRIBUTION - BELOW 10 MW

7. STATE ESTIMATOR QUALITY MONITORINGNORMALIZED RESIDUALS • ENABLES RANKING OF MEASUREMENTS OF DIFFERENT TYPES (MW, MVAR, AMPS, KV) BASED ON A NORMALIZED INDEX • BCH PERFORMANCE CRITERION: • NORMALIZED RESIDUAL GREATER THAN 10 UNITS INDICATES A MEASUREMENT OF A LOWER QUALITY • NEEDS IMPROVEMENT : DOES NOT REFLECT ERRORS OF GENERATOR UNIT MEASUREMENT AND OTHER INJECTION MEASUREMENTS

8. STATE ESTIMATOR QUALITY MONITORINGCONSISTENCY OF VOLTAGE STABILITY REGION

9. STATE ESTIMATOR PERFORMANCE TRACKING • TRACK SOLUTION QUALITY INDICES IN PI • IMPROVE ONLINE SEQUENCE DISPLAY TO INCLUDE ALERT SIGNALS (FLASHING APPLICATION STATUS BOXES) • MONITOR IMPACT ON OTHER APPLICATIONS E.G. VSA • PERFORM REGULAR REAL TIME TELEMETRY QUALITY ANALYSIS AND PRODUCE TELEMETRY QUALITY REPORTS • ISSUE TELEMETRY CALIBRATION REQUESTS • RTNET SOLUTION INVALIDATED IF QUALITY MEASURES OUTSIDE PERFORMANCE LIMITS

10. BASIC QUALITY INDICES

11. AVERAGE MEASUREMENT RESIDUALS

17. QUESTIONS?