基于改进固有时间尺度分解法的绝缘子泄漏电流去噪研究  

Research on De-noising of Insulator Leakage Current Based on Improved Intrinsic Time-Scale Deposition

作　　者：黄建才[1] 朱永利[1] 

机构地区：[1]华北电力大学控制与计算机工程学院,保定071003

出　　处：《电工技术学报》2013年第1期57-64,共8页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金资助项目(60974125)

摘　　要：绝缘子泄漏电流中的噪声严重影响对泄漏电流的分析。给出了适用于泄漏电流去噪的改进固有时间尺度分解(ITD)方法。通过引入距离尺度,解决了ITD方法中的旋转混叠问题,避免了各个固有旋转分量(PRC)之间的频率交叉现象;通过引入两端延拓,解决了ITD方法中的端点效应问题。提出了采用改进ITD对安全区泄漏电流去噪时分解次数的计算公式,解决了分解时的盲目性;在借鉴小波阈值合理性的基础上,结合改进ITD方法的特殊性,给出了去噪时的阈值和去噪过程。采用所提方法对高压试验中采集到的绝缘子泄漏电流进行了去噪。结果表明,所提方法既平滑了泄漏电流信号,又有效保留了特征成分,效果优于未改进ITD方法的去噪结果。The noise in the insulator leakage current influences the analysis for the leakage current greatly.The improved ITD(intrinsic time-scale decomposition) is proposed,which is fit to de-noise the leakage current.In this method the distance scale is introduced to solve the rotation mixing problem.It avoids the situation that each PRC(proper rotation component) contained the frequency of the others.The extension of the two ends is introduced to solve the end effect problem.When the improved ITD is used to de-noise the leakage current at the safety stage,the formula calculating the decomposition number is proposed,which avoids the blindness of the decomposition.Based on the wavelet threshold and the special characteristics of the improved ITD,the threshold and the de-noising process are given.This proposed method is applied on the de-noising of the leakage current gathered in the high voltage experiment.The result shows that the proposed de-noising method smoothes the leakage current signal effectively and keeps its feature components well,which is superior to the de-noising result of the original ITD.

关 键 词：绝缘子 泄漏电流 去噪 固有时间尺度 阈值 

分 类 号：TM835.4[电气工程—高电压与绝缘技术]