局部放电在线监测中基于小波变换的阈值消噪算法研究

小波变换的正交多分辨率分析可将信号在不同尺度下进行分解。通过对各尺度上的分解系数进行合适的阈值处理，可有效地消除局部放电在线监测中的窄带干扰，提取脉种信号。通过对仿真信号和现场信号的处理，结果表明该方法行之有效。

WAVELET TRANSFORM BASED DE-NOISE ALGORITHM BY THRESHOLDING IN ON-LINE PARTIAL DISCHARGE DETECTION

One of the key problems in on-line partial discharge (PD) detection is to suppress many of the sinusoidal signals, which interfere the PD identification. Under different scales and using orthonormal multiresolution analysis based on wavelet transform, the signals can be decomposed into many different levels. By appropriate processing of the decom-position coefficients on the scales according to the threshold values the interference signals can be effectively eliminated and the de-noised signals can be obtained. Through the simulated and on-site experiments, it is proved that this method is very effective.