摘要
介绍了利用零序电流的相关性进行小电流接地系统故障选线的一种新方法,以解决当零序电流中含有较强直流分量时由于电流互感器饱和引起电流采集信号波形畸变带来的选线失效问题。小电流接地系统发生单相接地故障后,非故障线路的零序电流波形是相似的,而故障线路零序电流波形与非故障线路差别较大。利用现代信号处理方法计算出其相关系数,分析各线路零序电流的相似性,确定故障线路。根据该原理开发了选线装置,并进行了实时数字仿真(RTDS)试验,试验结果表明在各种工况下都可以正确地选出故障线路。
A method of faulty line selection by the correlativity of zero sequence current is introduced for non- solid- earthed network to solve the problem of faulty line selection invalidation when CT saturation causes great DC component in zero sequence current. When single- phase grounding fault occurs in non- solid network,the zero sequence current waveforms of healthy lines are similar while that of faulty line is quite different. The zero sequence current correlation coefficients between lines are calculated with modem signal processing method and their similarities are analyzed to determine the faulty line. A faulty line selection device is developed based on this principle and the results of RTDS（Real Time Digital Simulator） simulation indicate that the faulty line can be selected correctly at any operating conditions.
出处
《电力自动化设备》
EI
CSCD
北大核心
2008年第9期64-67,共4页
Electric Power Automation Equipment
关键词
小电流接地系统
单相接地故障
互相关系数
波形畸变
non- solid- earthed network
single- phase grounding fault
correlation coefficient
waveform distortion
