一起断路器合闸单相延时的异常分析

针对一起换流站交流滤波器断路器C相合闸时间异常现象，分别开展断路器本体试验和二次控制回路检查，通过分析该断路器机械特性、气体成分、传动试验结果及合闸回路电压监测结果，最终确定异常原因为该断路器合闸回路过长导致合闸线圈两端电压降低，长期低压运行令断路器C相机构合闸线圈与衔铁动作配合性能下降，产生100 ms动作延时。根据分析结果对现有断路器控制回路进行优化改造，并对改造后回路持续监测，断路器三相可靠合闸动作均无延时。合闸线圈端电压提升至正常电压。

Analysis on the abnormality of the single phase delay for circuit breaker closing

In view of the abnormal closing time of phase C circuit breaker of the AC filter group in the converter station,the circuit breaker body test and secondary control circuit inspection were carried out respectively.Through analyzing the mechanical characteristics,gas composition,transmission test results and closing circuit voltage monitoring results of the circuit breaker,the causes were concluded that the long closing circuit of the circuit breaker led to the voltage reduction at both ends of the closing coil.Long time low-voltage operation reduced the cooperation performance between the closing coil and the armature of the phase C mechanism of the circuit breaker,resulting in 100 ms action delay.According to the analysis results,the control circuit of the circuit breaker is optimized,and the improved circuit is continuously monitored.The three-phase closing action of the circuit breaker was reliable without delay,and the voltage at the end of the closing coil restored to the normal voltage.