基于小波能量和EMD小电流接地故障选线  

Fault line selection based on wavelet energy and EMD in non-solid-earthed network

作　　者：孙蓉[1,2] 马寿虎 葛乐[3] 杨志超[3] 

机构地区：[1]河海大学能源与电气学院,南京211100 [2]国网江苏省电力公司电力科学研究院,南京211103 [3]南京工程学院电力工程学院,南京211167

出　　处：《中国科技论文》2017年第11期1247-1251,共5页China Sciencepaper

基　　金：国家自然科学基金资助项目(61473144);江苏省产学研联合前瞻性项目(BY201500905);江苏省电力公司科技基金资助项目(J2016018)

摘　　要：针对小电流接地系统中故障合闸角在0°附近时现有选线方法成功率低的问题,提出1种新的选线方法。该方法将暂态零序电流进行小波包变换和经验模态分解(empirical mode decomposition,EMD),在变换分解的过程中,根据不同的故障合闸角求取不同的故障特征量。若故障合闸角在0°附近,则求取各馈线的衰减直流分量,其极大值的馈线即为故障线路;若故障合闸角在90°附近,则求取各馈线的小波能量,其极大值即为故障线路;若衰减直流分量或小波均无极大值,则母线故障。在PSCAD/EMTDC中对搭建的6条电缆馈线的配网模型进行仿真,并通过MATLAB处理仿真数据。仿真结果证明了该方法在不同条件下小电流接地故障选线的准确性。In view of low success rate of fault line selection when fault close angle was near zero in the small current neutral grounding system,a new method of fault line selection was presented in this paper.The method was based on wavelet packet transform and empirical mode decomposition（EMD）of transient zero sequence current.In the process of transformation and decomposition,different fault characteristics were calculated according to different fault closing angle.If fault closing angle was near 0°,the decaying DC component of each feeder was calculated,and maximum value of feeders is the fault line.If the fault closing angle is near 90°,wavelet energy of each feeder is calculated,and maximum value of feeders is the fault line.If the decaying DC component or wavelet has no maximum value,it is bus fault.In this work,model of distribution network of 6cable feeder was simulated by PSCAD/EMTDC,and simulation data was processed by MATLAB.The simulation results showed the accuracy of method for different fault selection in small non-solid-earthed network.

关 键 词：小电流接地系统 接地故障选线 小波能量 经验模态分解 

分 类 号：TM862[电气工程—高电压与绝缘技术]