电力系统故障信号小波消噪应注意的问题

An attentive problem on wavelet-based reduce noises of fault signals of electronic power system

小波由于其时频窗口的灵活性 ,使小波变换近几年来在电力系统故障信号处理中得到广泛应用。特别是 ,电机的故障信号含有大量的噪声 ,有时噪声将故障信号完全淹没 ,很难直接用于故障的分析和诊断。所以在故障信号分析之前 ,必须对故障信号进行消噪。然而小波变换并不是对所有噪声都是有效的。故提出了将三角样条调频小波方法用于噪声的消噪 。

Wavelets have inflexible time-frequency windows, so wavelet transforms have been used to process fault signals of electric power systems extensively. In particular, the fault signals contain many kinds of noise. Sometimes, fault signals are submerged by noise, so it is difficult to analyze and diagnose directly. It is essential to denoise before analyzing. But, wavelet transforms are not always validated to denoise all kinds of noise. So, in this paper, LFM trigonometric spline wavelets are being used to reduce noises. The result has be demonstrated by the example.