小波分析在气体绝缘组合电器局部放电检测中的应用

The Application of Wavelet Transform in the Diagnostic Measurement of Partial Discharge in GIS

采用两种检测手段,测量了在气体绝缘组合电器(GIS)局部放电模拟系统中,由内导体固定突起所产生的局部放电。一种有效的滤除干扰的信号处理方法——小波分析法被应用于这个系统。结果表明,在背景有较强干扰情况下,由于小波分解的局部特性,在检测局部放电时优于传统的付里叶频谱分析方法及在单纯频率范围滤波的方法。

The partial discharge (PD) signals produced by a fixed protrution were measured by two PD measuring methods in a simulating system of Gas Insulated Switchgear (GIS). A way of noise rejection by a powerful tool. i. e. the wavelet transform was used in the system. Because of the local focus characteristics of the wavelet transform, the main characteristics of the PD signals could be abstracted under serious noise background. This is an application of an algorithm that removes noises from signals by analyzing the evolution of the wavelet transform maximums across scales. It is clear from the analysis that the signal processing on the basis of wavelet transform is really superior to the traditional method of spectrum analysis of FFT.