220kV变电站35kV电容器组差压保护频繁动作的原因分析

Cause Analysis on Frequent Differential Protection Actions of 35 kV Capacitor Bank in 220 kV Substation

某变电站35kV1号电容器连续在4天内发生了3起差压保护动作事件。经过现场检查及电容器试验后,排除了电容器内部故障的可能性。在考虑外部因素时提出假设,并通过理论分析和电能质量测试,最终证实了谐波是导致电容器熔丝多次熔断的主要原因。

Three differential protection action events occurred in 35 kV #1 capacitor bank in a substation in four days. By field examination and capacitor test,the possibility of internal capacitor fault is excluded. The paper makes assumptions while its takes the external factors into account, and through theoretical analysis and power quality test it proves that the frequent capacitor fusing is mainly caused by harmonic.