基于小波能量谱的输电线路雷击故障识别方法研究  

Identification Method of Lightning Fault for Transmission Lines Based on Wavelet Energy Spectrum

作　　者：李晓斌[1] 赵东阳[1] 钟光强[1] 郑富春 吴昊[2] 王琪[2] 姚陈果[2] 王俊凯[2] 

机构地区：[1]国网重庆市电力公司长寿供电分公司,重庆401220 [2]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400044

出　　处：《电测与仪表》2014年第12期34-39,共6页Electrical Measurement & Instrumentation

摘　　要：准确辨识输电线路雷击故障类型对于改进防雷设计、实现差异化防雷具有十分重要的意义,因此以雷击输电线路后三相导线暂态行波电流为研究对象,建立了基于小波能量谱的雷击故障识别方法。根据不同雷击情况下的小波能量谱分布特点,构建了相应特征量及故障识别判据。仿真结果表明,该方法不受雷电流参数及波形的影响,对于绕击未闪络、绕击闪络及反击三种雷击类型均能准确识别。通过合理选择判断阈值和电流行波监测点,可分别避免雷电冲击电晕及线路末端折反射波对算法准确性的影响,因此本方法具有较高的实用价值。Accurate identification of lightning fault is of great significance for improving the transmission line lightningprotection design. In this paper, the three-phase travelling wave current is studied. Based on the wavelet energy spec-trum, a lightning fault identification method is established. According to the distribution characteristics of the waveletenergy spectrum for different lightning faults, the corresponding characteristic and fault identification criterion are con-structed. The simulation results show that, the method is not affected by parameters and waveforms of lightning currentmodels. It can distinguish accurately the three fault types, which are shielding failure without flashover, shielding fail-ure with flashover and back flashover. By choosing the threshold and setting the detection point reasonably, it can re-spectively avoid the effect of lightning impulse corona and reflected wave at the end of the line on the accuracy of themethod. Therefore, the method has high practical value.

关 键 词：输电线路 雷击故障 识别方法 小波能量谱 

分 类 号：TM863[电气工程—高电压与绝缘技术]