基于线电压和零模电流的小电流接地故障暂态定位方法

为解决配电网小电流接地故障时故障点定位困难的问题,提出一种基于线电压和零模电流暂态分量的故障定位新方法。该方法借助馈线自动化(feeder automation,FA)系统实现,不需要额外增加设备。馈线终端检测线电压和零模电流信号,利用暂态线电压的希尔伯特变换与暂态零模电流的乘积计算故障方向参数,FA主站根据故障点前后方向参数极性相反的特征确定故障点所在的线路区段。介绍基于线电压的小电流接地故障检测和接地故障相确定的算法。数字仿真与试验结果表明该方法是正确可行的。

Transient Fault Locating Method Based on Line Voltage and Zero-mode Current in Non-solidly Earthed Network

In order to solve the fault location problem of single phase grounding fault in non-solidly earthed distribution network,a new fault location method based on transient component of line voltage and zero-mode current was presented.This method is realized by the feeder automation(FA) system and does not require additional equipment.The product of transient line voltage after Hilbert transformation and transient zero-mode current is defined as the parameter of fault direction,calculated by the feeder terminal unit(FTU).The fault section is located by master station according to opposite polarity of direction parameter before and after fault point.The algorithm of detecting single phase grounding fault and confirming the fault phase was introduced.Results of digital simulation and experiment demonstrated the accuracy and feasibility of this method.