Transmission voltage recovery delayed by stalled air conditioner compressors

Southern California Edison Company (SCE) has experienced delayed voltage recovery following fault clearing on the transmission system. The authors describe these occurrences and document the studies which successfully modeled the voltage recovery process. The studies showed how the stalling of single-phase air conditioner compressors following a power system fault was the root cause of delayed voltage recovery. Tests of air conditioner response to voltage dips are documented. The results of these tests are used to derive the mathematical load models used in voltage recovery studies