基于同步压缩域多级阈值变压器局部放电噪声抑制方法  

Noise Suppression Method for Transformer Partial Discharge Based on Multi-stage Threshold in Synchro-squeezing Domain

作　　者：徐艳春[1] 夏海廷 李振华[1] Mi LU XU Yanchun;XIA Haiting;LI Zhenhua;Mi LU(Key Laboratory of Operation and Control of Cascade Hydropower Stations in Hubei Province,China Three Gorges University,Hubei Yichang 443002,China;Department of Electrical and Computer Engineering,Texas A&M University,College Station,Texas,USA 77840)

机构地区：[1]三峡大学梯级水电站运行与控制湖北省重点实验室,湖北宜昌443002 [2]Department of Electrical and Computer Engineering,Texas A&M University,College Station,Texas USA 77840

出　　处：《高压电器》2021年第6期123-131,共9页High Voltage Apparatus

基　　金：国家自然科学基金(51507091)。

摘　　要：传统局部放电时频分析噪声抑制方法,存在时频分辨率低、可读性差和抑制噪声种类单一的局限。文中在同步压缩域中使用多级阈值方案对变压器局部放电检测时所受干扰:白噪声和窄带噪声进行抑制。同步压缩算法作为一种高分率的时频分析方法,旨在对时频域进行重新分配,更细致区分信号与噪声。多级阈值方案结合小波变换和同步压缩变换,利用信号的高阶统计特征计算噪声的初级阈值,完成对原始信号噪声的初步抑制;利用广义交叉验证算法求解噪声的次级阈值,完成对信号中残留噪声更进一步的抑制。文中所提基于同步压缩域的多级阈值噪声抑制方案能有效的对两种噪声进行抑制,信号失真度低。The traditional partial discharge time-frequency analysis de-noising method has the limitations of low timefrequency resolution,poor readability and single de-noising type.In this paper,the de-noising scheme of multi-stage threshold based on synchro-squeezing is used to filter out narrowband noise and white noise.As a high-rate time-frequency analysis method,the synchro-squeezing algorithm is designed to redistribute the time-frequency domain to distinguish the signal and noise more carefully.The multi-stage threshold scheme combines wavelet transform and synchro-squeezing transform to calculate the initial threshold of noise by using the characteristics of high-order statistics of the signal,thus completing the preliminary suppression of the original noisy signal.Then,the generalized cross validation algorithm is used to solve the secondary threshold of noise to further suppress the residual noise in the signal.The proposed method can effectively suppress the two kinds of noise and the signal distortion is low.

关 键 词：局部放电 噪声抑制 同步压缩 多级阈值 小波变换 

分 类 号：TM855[电气工程—高电压与绝缘技术]