干式并联电抗器频繁击穿原因分析

Analysis of Frequent Breakdown of Dry Type Shunt Reactor

根据某变电站干式并联电抗器多次击穿故障情况,现场开展了投切过电压测试,测试结果表明该断路器在合闸和分闸过程中均产生了幅值较高的过电压。通过对过电压产生原因以及避雷器保护效果的分析,确认真空断路器投切过程中产生的过电压超出电抗器绝缘水平是导致故障的主要原因,并提出将真空断路器更换为SF6断路器的整改措施。运行结果证明该措施的有效性,为今后类似情况的处理提供了依据。

Aiming at the multiple breakdown faults of a dry-type shunt reactor in a substation,the overvoltage test during switching is carried out on site.The test results show that the circuit breaker produces high amplitude overvoltage in the process of switching.Through the analysis of the causes of overvoltage and the protection effect of arrester,it is confirmed that the main cause of the fault is that the overvoltage generated in the switching process of vacuum circuit breaker exceeds the insulation level of reactor.This research suggests the improvement measures of replacing vacuum circuit breaker with SF6 circuit breaker.The operation results show that this measure is effective and provides a basis for other similar cases.