转移型消弧装置对线路首端断线故障试验处理异常分析

Analysis of the Abnormal Treatment of the First End Line Failure Test by Using Transferring-Type Arc-Suppression Device

针对故障转移消弧装置发生首端断线故障,装置不能准确选相并可靠动作,可能会进一步发生变电站相间短路故障的问题,在某10 k V配电真型试验场进行了故障接地转移装置首端断线故障试验,分析了配电网首端断线故障特征。试验结果表明,线路首端断线故障与单相接地故障的母线电压变化有相似之处,故障转移消弧装置仅利用中性点位移电压的变化和相电压的变化来判断是否发生单相接地故障是不可靠的,装置会出现选相错误的现象,应增加零序电流的判据条件加以限制。

In view of the potential failure at the first end line by using transferring-type arc-suppression device,which cannot accurately select the phase and act reliably,and may further cause the problem of inter-phase short circuit fault in the substation,the first end broken line fault test of the fault grounding transfer device has been carried out in a 10 kV distribution true test field,followed by an analysis of the fault characteristics of the first end of the distribution network.The test results show that the fault of the first end line is similar to the change of the busbar voltage of the single-phase grounding fault.The fault transfer arc suppression device only uses the change of neutral point displacement voltage and the change of phase voltage to judge whether a single-phase grounding fault occurs,which result is not reliable.The phase selection error will occur in this device,therefore,the criterion of the zero sequence current should be increased.