【摘要】 本文尝试将小波变换应用于提高用脉冲电流法测得的局部放电脉冲的信噪比。本文先采用二进尺度离散序列小波变换Ｍａｌａｔ算法，应用Ｄａｕｂｅｃｈｉｅｓ小波设计了低通、带通滤波器，再根据连续小波变换的基本理论编制程序。然后用上述两种方法对模拟现场数据和现场采集数据进行处理以验证小波变换的去噪能力。结果表明，小波变换能快速而有效地从不同窄带干扰中提取出放电信号。结果同时表明，由于白噪与局部放电信号的Ｌｉｐｓｃｈｉｔｚ指数明显不同，从而可以利用原信号中信号与白噪的小波变换极大值在多尺度上的变化的差异，区别局部放电信号与白噪声，从而将放电信号从白噪中鉴别出来。更多还原

【Abstract】 This text tried to apply wavelet transform in detecting the partial discharge(PD) signal in transformer.At first,dyadic wavelet transform was applied to design lowpass and strap pass filter,and then,according to theory of integral wavelet transform the program for wavelet transform was completed.Then the two methods mentioned above were applied to process the simulated data and on site detected data.We can draw a conclusion that wavelet transform can extract PD signal from many kinds of narrow band disturbance.At the same time,taking advantage of the distinctness of Lipschitz exponential between the signal and the white noise in different wavelet scale,we can distinguish the PD signal from white noise.更多还原