Transient Voltages across Series Capacitors on Three-Phase Transmission Line due to Non-Simultaneous Switching

Abstract

Series capacitors have been utilized recently in order to increase the capacity of transmission systems by compensating the detrimental effects of inductance. In such cases, these capacitors have to be switched in or off according to the variation in load. This is necessarilly accompanied by power disturbances, abnormal voltage rises etc.. In order to insert the capacitors, the circuit breakers that are installed in parallel with them are opened, in which case it is scarcely possible to open all three poles of the breakers simultaneously. The present paper deals analytically the abnormal transient voltages across the capacitors arising due to non-simultaneous tripping of the poles, and the validity of the analytical results are affirmed by comparing with many experiments recently executed.