基于故障指示器的10kV系统单相接地故障选线及实验

Fault Selection and Experiment for Single Phase Ground Fault based on Fault Indicator in 10kV Distribution Networks

为克服现有故障指示器在单相接地故障选线和定位时灵敏度低、容易误判等不足,采用基于不对称工频电流注入的新型故障指示器。首先在介绍故障指示器基本结构的基础上,阐述了单相接地故障判断的工作原理。最后,在10k V配电网上对高阻接地与金属性接地进行了详细地实验和对比分析。结果表明,本实验采用的故障指示器能有效选线并定位故障区间,大幅缩短了故障点查找和排除时间。

To overcome the shortage of low sensitivity and misjudge easily for the single phase ground fault line selection and location in existing fault indicators, a novel fault indicator is proposed based on asymmetric power frequency current injection method. On the basis of the introduced basic structure of the proposed fault indicator, the working principle for deciding single phase ground fault is elaborated. Finally, detailed experiments and comparative analysis for high impedance grounded fault and metallic grounded fault are carried out in 10 k V distribution networks. Results show that, the proposed fault indicator can select line and locate fault section effectively, and shorten time of search and elimination for fault point significantly.