基于经验小波变换与Hilbert边际谱的电缆局部放电定位方法

Cable partial discharge location based on EWT and Hilbert marginal spectrum

针对背景噪声干扰和放电信号匹配影响电缆局部放电定位精度的问题,提出一种基于经验小波变换与Hilbert边际谱的局部放电定位处理方法。通过建立振荡波电压局部放电仿真模型产生局部放电信号,经EWT分解信号,获取多分辨率分量。采用Hilbert变换对MRA分量求其边际谱能量值,计算脉冲匹配,将放电信号接收时间代入行波公式计算出故障位置。结果表明,该方法可以有效实现放电信号匹配,与传统定位方法相比,精度更高,定位误差达到0.33%。

This paper proposes a partial discharge localization method based on empirical wavelet transform and Hilbert marginal spectrum to address the accuracy of cable partial discharge localization affected by background noise interference and discharge signal matching.The study is performed by establishing a voltage partial discharge simulation model of the oscillating wave to generate partial discharge signals;obtaining the multi-resolution components by decomposing signal with EWT;using Hilbert transform to calculate the marginal spectrum energy value of MRA components and pulse matching;and substituting the reception time of discharge signal into the traveling wave calculation formula to calculate the fault location.The results show that compared to traditional positioning methods,this method can effectively achieve discharge signal matching with higher accuracy of position error of 0.33%.