摘要
传统的线路过电流保护以电流值的大小为特征量,通过整定短路电流值来检测短路故障,可能会出现整定值与最大负荷电流值重合,引起误动;对于高过度电阻故障也不灵敏。小波变换可以对故障进行时-频分析,将故障电流的频域特征提取为特征量,对故障进行有效检测。文章介绍了极大堆叠离散小波变换(MODWT)分析线路短路故障的一般思路,以及现有的一些故障特征量选取方法,并对相关研究以及应用进行了展望。
Traditional line over-current protection takes the current value as the characteristic quantity,and detects short-circuit faults by setting the short-circuit current value.The setting value may overlap with the maximum load current value,thus causing malfunction;and it is also insensitive to high excessive resistance faults.Wavelet transform can perform time-frequency analysis on faults,extract the frequency domain characteristics of fault currents as characteristic quantities,and effectively detect faults.This paper introduces the general idea of MODWT analysis of line short-circuit faults,as well as some existing fault feature selection methods,and puts forward prospects for related research and applications.
出处
《科技创新与应用》
2021年第6期28-30,共3页
Technology Innovation and Application
关键词
线路保护
故障特征
MODWT
时频分析
line protection
fault characteristics
MODWT
time-frequency analysis
