基于高阶累积量的局部放电超高频信号时延估计算法  

Time-delay Estimation Algorithm of Partial Discharge Ultra High Frequency Signals Based on Higher-order Cumulant

作　　者：侯慧娟[1] 盛戈皞[1] 朱文俊[2] 王红斌[2] 江秀臣[1] 

机构地区：[1]上海交通大学电气工程系,上海200240 [2]广东电网公司电力科学研究院,广州510080

出　　处：《高电压技术》2013年第2期342-347,共6页High Voltage Engineering

基　　金：国家高技术研究发展计划(863计划)(SS2012AA050803);上海市科委项目(10dz1203000)~~

摘　　要：时延估计是基于时间差的变电站局部放电空间定位算法的基础,也是决定定位准确度的关键。为此,以Tugnait的高阶统计量理论为基础,提出了基于4阶累积量的局部放电超高频(UHF)信号时延估计算法,并给出了具体的时延计算方法。该算法以高阶累积量代替信号本身来进行相关分析,估算得出信号时延,具有对相关特性未知的Gaussian噪声不敏感的优点。仿真实验利用双指数振荡衰减函数,并加入Gaussian噪声和定频干扰,模拟变电站现场局部放电超高频信号,利用该时延估计算法可以准确得到信号时延。最终利用该算法计算变电站实测多路超高频信号的时延,并将该时延序列应用于基于天线阵列的变电站局部放电定位,估算出局部放电源的空间位置,且定位误差<0.3m,验证了该算法的有效性和实用性。Time-delay estimation is the basis of the location algorithm for partial discharge based on time difference in substations,and it is the key to the accuracy of location.According to the higher-order statistics theory raised by Tugnait,a novel time delay estimation algorithm for partial discharge ultra-high frequency（UHF） signals is put forward based on 4-order cumulant.The algorithm substitutes high-order cumulants for the signals themselves to analyze the correlation,then the signal time delay is gained after estimating the time delay between signals.The presented method has advantages in its insensitive to Gaussian noises with unknown related characteristics.The signals of the UHF caused by partial discharge are simulated by double exponential oscillation decay function,interfered by Gaussian noises and fixed-frequency signals,meanwhile,the accuracy of the algorithm has been verified by the simulated signals.Finally the algorithm has been used to calculate the time delay of field partial discharge（PD） signals,and the sequence of the delay has been applied to substation PD location based on antenna array.The PD source location is estimated,and the locating error is less than 0.3 m.Therefore the effectiveness and practicality of the algorithm are verified.

关 键 词：时延估计 变电站 局部放电 定位算法 超高频(UHF) 高阶累积量 

分 类 号：TM855[电气工程—高电压与绝缘技术]