基于EEMD阈值的绝缘子泄漏电流去噪的研究

Research on De-nosing of Insulator Leakage Current Based on EEMD Threshold

绝缘子泄漏电流信号的采集受很多噪声信号的干扰,直接使用将影响准确地提取其特征量,本文对基于EEMD(Ensemble Empirical Mode Decomposition)阈值的绝缘子泄露电流去噪方法进行研究,借鉴小波去噪的4种阈值方法对泄漏电流信号进行去噪,分别是自适应阈值、固定阈值、启发式阈值和极大极小阈值,对EEMD阈值的去噪方法进行研究,通过对去噪前后信号的波形、有效值和谐波幅值比这3个特征量进行分析比较,综合比较仿真和实测信号去噪前后的效果,得出固定阈值是EEMD去噪方法的最佳阈值。

There is a large amount of noise in the process of measuring insulator leakage current, so it is a difficult task to pick up useful information if we use the signal directly. In this paper, we use four threshold, namely, the self-adaptive threshold, the fixed threshold, the heuristic threshold and the minimax threshold to filter the noises from measured leakage current with different signal-to-noise ratio （SNR） based on the research of the EEMD （Ensemble Empirical Mode Decomposition） de-noising method. Through the analysis and comparison of three characteristics of the signal pre-and-post de- noised, including waveforms, RMS and harmonic amplitude value ratio leakage, and the effect of simulation and actual measurement for signal pre-and-post de-noised. It is obtained that fixed threshold is the best threshold for EEMD De-nosing Method.