基于VMD-WVD相位法的长电缆局放双端定位  

Double-ended positioning of partial discharge for long cable based on VMD-WVD phase method

作　　者：陈皇熹 方春华[1] 普子恒[1] 吴田 CHEN Huangxi;FANG Chunhua;PU Ziheng;WU Tian(College of Electrical Engineering and New Energy,China Three Gorges University,Yichang 443002,China)

机构地区：[1]三峡大学电气与新能源学院,湖北宜昌443002

出　　处：《电力工程技术》2022年第3期171-177,共7页Electric Power Engineering Technology

基　　金：国家自然科学基金资助项目(51807110)。

摘　　要：快速准确定位电缆局放故障位置对电缆系统安全稳定运行具有重要意义。针对传统行波定位法在长电缆局放定位时反射信号难以识别以及存在时间同步误差的问题,提出一种基于变分模态分解-维格纳威尔分布(VMD-WVD)相位法的电缆局放双端定位方法,通过准确标记双端局放信号波头时刻实现双端局放信号的同步,利用相位定位实现长电缆局放入射信号的双端同步。文中建立了长线路PSCAD模型,分析故障位置、电缆长度和采样率对VMD-WVD相位法在长电缆定位的精度影响。结果表明,在上述3种因素影响下,VMD-WVD相位法的平均定位精度分别为0.54%,0.85%,0.69%,高于传统行波定位法。文中研究成果为长电缆局部放电精准定位提供一种全新思路。Obtaining the cable partial discharge fault location quickly and accurately is of great significance to the safe and stable operation of the cable system.In order to resolve the problem of the traditional traveling wave positioning method on time synchronization,a double-ended positioning of partial discharge for cable based on variational mode decomposition-Wigner Ville distribution(VMD-WVD)phase method is proposed to reduce the influence of reflected waves identification in long-cable.It is marked the wave head of the double-ended partial discharge signal accurately to achieve the synchronization of the double-ended partial discharge signal by the proposed method.Through phase positioning,the advantages that synchronizing the incident signal of double-ended partial discharge in the long cable are realized.It is built a PSCAD model of a long line to analyze the positioning accuracy of the VMD-WVD phase method under the influence of fault location,cable length and sampling rate in long cables.The results show that the average positioning accuracy by the VMD-WVD phase method for the above three influencing factors is 0.54%,0.85%and 0.69%respectively,which is higher than the value by the traditional traveling wave positioning method.The research results provide a new idea for the precise positioning of partial discharge in long cables.

关 键 词：长电缆 变分模态分解-维格纳威尔分布(VMD-WVD) 局放信号 波头时刻 双端定位 定位精度 

分 类 号：TM755[电气工程—电力系统及自动化]