10kV无功补偿电容器分相合闸策略研究

Study on Phase Closing Strategy of 10kV Reactive Compensation Capacitor

在江门某变电站,搭建10kV无功补偿电容器分相投切实验系统。断路器采用随机合闸策略,无功补偿电容器最大暂态过电压为稳态运行的1.6倍左右,最大暂态过电流为稳态运行的3.7倍左右,暂态持续时间约为170 ms;而采用分相合闸策略,无功补偿电容器最大暂态过电压不会超过稳态运行的1.3倍,最大暂态过电流不会超过稳态运行的2倍,暂态持续时间约为130 ms。采用分相合闸策略能够有效减小电容器合闸过电压和合闸涌流,减少暂态持续时间,从而提高电容器运行的安全性与可靠性。

The phase switching experimental system of 10 kV reactive compensation capacitor is set up at certain substation in Jiangmen. The random closing strategy is adopted in the circuit breaker, the maximum transient overvoltage of reactive compensation capacitor is about 1.6 times that of steady operation, the maximum transient overcurrent is about 3.7 times that of steady operation and the transient duration is about 170 ms. However, in case of adopting phase closing strategy, the maximum transient overvoltage of reactive compensation capacitor will not exceed 1.3 times that of steady operation, the maximum transient overcurrent will not exceed twice that of steady operation and the transient duration is about 130 ms. The use of phase closing strategy can reduce effectively the closing overvoltage and the closing inrush current of the capacitor, reduce the transient duration, thus improving the safe and reliable operation of the capacitor.