基于数学形态谱的配电网接地选线新方法

Faulty grounding line selection based on pattern spectrum in power distribution system

分析了配电网故障选线的现状,提出了一种新的基于图形识别的数学形态谱选线方法。从配电网发生单相接地时各线路的零序电流波形出发,采用不同刻度大小的结构元素对电流波形进行形态学开、闭运算,将运算结果对刻度求导,得到形态谱值曲线,求出各线路形态谱,找出形态谱不同于其他线路的线路即是故障线路。Matlab仿真结果表明,该方法不受有无中性点消弧线圈、过补偿度、过渡电阻和短路时刻的影响,能准确地选择出故障线路,为配电网单相接地选线提供了一种全新的思路。

The development of faulty line selection in distribution system is analyzed and a taulty line selection method of pattern spectrum based on image recognition is presented. The zero sequence current waveform of each line during single-phase grounding fault is recognized and the structure elements of different scales are used to transform the signals by open or close operation. The pattern spectrum curve is derived by differentiating the results to scale and the faulty line is selected by finding the line whose pattern spectrum is different from others＇. Matlab simulation test shows that, it selects the faulty line correctly, immune from the grounding fault neutralizer, over-compensation, transition resistance and fault occurrence time.