改进空间屏蔽滤波算法在局部放电脉冲提取中的应用

提出了改进的空间屏蔽滤波算法，并将其应用于局部放电脉冲信号的提取。利用Teager能量算子得到能量强化后的小波变换系数，利用小波系数在相邻尺度的乘积突出奇异性信号，形成基于尺度的屏蔽滤波器，通过相邻屏蔽滤波器的逻辑“与”运算得到最终的屏蔽滤波器。将该屏蔽滤波器和不同尺度的小波系数相乘来提取局部放电脉冲。仿真信号和试验室线棒放电信号的测试表明该方法不仅能提高信噪比，还能很好保留局部放电信号的幅值和能量，有利于后续的局部放电分析。

APPLICATION OF IMPROVED SPATIAL MASK FILTER ALGORITHM IN PARTIAL DISCHARGE PULSE EXTRACTION

In this paper, an improved spatial mask filter algorithm is proposed and applied in partial discharge pulse extraction. Teager operator is used to strengthen wavelet coefficient local energy. Direct multiplication of coefficients at adjoining scales distinguishes signal singularity and obtain spatially selective filter based on scales. AND logic operator is used in different filter to get the last spatial mask filter. Partial discharge pulses are extracted through multiplication of wavelet coefficients and mask filter. Simulation method and bar discharge signal simulation test indicated that this algorithm will not only increase the signal to noise ratio(SNR),but also preserve the energy and pulse amplitude. This is very important for partial discharge analysis.