GIS设备局部放电图谱噪声抑制方法

针对GIS设备典型缺陷的局部放电图谱主要受白噪声干扰的问题,提出一种空域修正阈值的小波去噪方法。首先对小波变换的各种去噪算法进行了比较分析,由于小波去噪中的阈值算法存在着固有缺陷的使去噪效果并不十分理想,也不够稳定,然后本文提出将小波阈值算法与空域相关算法有机结合,同时给出一种新的阈值选择方法,对信号进行联合去噪。实验结果表明,本文提出的方法与传统方法具有明显优势,不但能在较强干扰情况下有效地将PD信号提取出来,且去噪后能量损失小,反映原始信号的特征尖峰点得到了较好的保留,波形峰值下降比较小。

Research on Noise Suppression Method of the GIS Equipment Partial Discharge

Partial discharge for the typical defects of the GIS equipment are mainly affected by white noise interference problems, it is proposed the wavelet threshold de - noising method of correction in this paper. Firstly, the some de - noising methods of wavelet transform were compared, because the wavelet threshold algorithm noise exists in the inherent defects of the de - noising effect is not very ideal, but is not stable enough. Then wavelet threshold algorithm and spatial correlation is combined, at the same time, it is given a new threshold selection method of the signal de - noising. In this paper, it is showed that the proposed method has obvious advantages than the traditional method that has not only strong interference effectively the PD signal is extracted, and the energy loss noise is small. And feature point spikes that reflect the original signal better retains. The wave peak value decreased relatively small.