基于聚类分析和相关分析的故障选线方法

Faulty Line Selection Method Based on Correlation Analysis and Cluster Analysis in Distribution Network

为准确选出谐振接地系统单相接地故障线路,提出一种相关分析与聚类分析相结合的选线方法。根据系统单相接地故障后零序暂态电流在故障线路和健全线路的差异,首先运用相关分析得到各线路零序暂态电流的综合相关系数并以此选取候选故障线路;然后求取各线路零序暂态电流之间的综合欧氏距离,以综合欧氏距离为基础对各线路进行聚类分析,依据聚类结果结合相关分析得到的候选故障线路最终确定故障馈线。理论分析和大量仿真结果表明,该方法可以有效避免运用相关分析法时因各线路零序电流相关性减弱造成的选线误判问题,并且选线结果准确、可靠。

In order to choose accurately the single phase to ground fault line in resonant earthed system, a method of detection based on correlation analysis and cluster analysis was proposed. According to the characteristic of the zero sequence transient current, correlation analysis is used to get the comprehensive correlation degree of all the lines to determine the candi- date faulty lines; and then calculate the comprehensive Euclidean distance of the zero sequence transient current, and cluser the zero sequence transient current of the feeder lines based on Euclidean distance, by the result of cluster analysis to select the fault line from the candidates. The theory and simulation results show that the method can be used to resolve the mistaken-selection caused by the weak correlation of zero sequence transient current and the result is accurate and reliable.