基于零序电流特征量的选择性漏电保护选线方法

针对现有选择性漏电保护装置灵敏度低、可靠性差的问题,提出了一种基于零序电流特征量的选择性漏电保护选线方法;分析了供电系统漏电故障时各支路零序电流的逻辑关系,介绍了基于零序电流特征量的选择性漏电保护选线方法的原理及实现。该方法根据各支路零序电流互感器二次侧零序电流的逻辑关系及数值关系建立特征量,并以该特征量作为选线判据。Matlab仿真结果表明,该方法能够有效地选出故障线路。

Line Selection Method of Selective Leakage Protection Based on Characteristic Quantity of Zero Sequence Current

In allusion to the problem of low sensitivity and poor reliability of existing selective leakage protection device,the paper proposed a line selection method of selective leakage protection based on characteristic quantity of zero-sequence current.It analyzed logical relationship of zero-sequence current of each branch during failure of power supply system and introduced principle and realization of the method.The method creates characteristic quantities according to logical relationship and value relationship of secondary side zero-sequence current of zero-sequence current transformer of each branch,and takes the characteristic quantities as criterion of line selection.Matlab simulation result showed the method can effectively select the fault line.