Phasor measurement systems in the WECC

This paper presents the use of phasor measurement units (PMUs) in the Western Electric Coordinating Council (WECC) has been very successful. Phasor data recorded during the Aug. 10, 1996 blackout showed the phase difference growing as the system weakened well before system separation. It also showed clearly the dynamic system behavior before and during the blackout. WAMS measurements, particularly phasor measurements, filled the need to see system behavior that other measurements did not cover. Phasor measurements are now widely dispersed in the WECC, most of the in real-time systems. More of these are being connected in wide-area networks to support continuing efforts to improve operations