基于暂态零序电流幅值比较的配电网单相接地故障定位

Power Distribution Network Single Phase Grounding Fault Positioning Based on Amplitude Comparison of Transient Zero-Sequence Current

阐述了中性点非有效接地系统零序网络的相频特性,分析了故障线路首容性频段内暂态零序电流,指出正常区段两端的暂态零序电流幅值近似相同,故障区段两端的暂态零序电流上游的幅值远大于下游的幅值,并据此提出了比较相邻馈线终端装置(FTU)暂态零序电流幅值的故障定位方法。仿真分析表明,该方法对于中性点不接地或经消弧线圈接地系统均适用,能够很好地克服故障时刻和过渡电阻的影响。具有暂态零序电流幅值大、检测灵敏度高、数据传输量小且不需要时钟精确同步的特点。

This paper described the phase frequency characteristics of neutral point non-validity grounding system zero-sequence network, analyzing transient zero-sequence current within fault line first capacitive frequency band and pointing out that the transient zero-sequence amplitude of normal section＇s both ends is nearly the same, while the upper reaches of fault section is much larger than the lower ones. On the basis of this, a new fault positioning method was raised to compare adjacent FTU transient zero-sequence current amplitude. Simulation analysis shows that the method is adaptable to both neutral point grounding and through-arc-extinction coil grounding system, being able to overcome the influence of fault time and interim resistance, with large transient zero-sequence amplitude, high test sensitivity, small data transmission and non-clock accurate synchronous etc characteristics.