基于经验小波分析的小电流接地系统单相接地故障选线方法

Single phase grounding fault line selection method based on EWT for small current grounding system

针对小电流接地系统单相接地故障选线中因故障特征量不明显而导致选线困难甚至误选的问题,提出了一种基于经验小波变换(Empirical Wavelet Transform,EWT)的小电流接地系统单相接地故障选线方法。该方法利用经验小波变换能自适应分割傅里叶频谱以分离不同模态和提取调幅-调频模态函数的优点,对小电流接地系统中单相接地故障零序电流的模态分量进行提取,并以零序电流的低频模态分量综合相关系数和高频分量能量值实现故障线路的综合选线。最后在Matlab仿真软件中验证了所提方法的有效性和优越性。

In view of the small current grounding fault line selection system for single-phase fault feature is not obvious due to difficulties even wrong line selection problem,a small current grounding system fault line selection method is proposed based on empirical wavelet transform(EWT).The method uses empirical wavelet transform to advantages of adaptive segmentation to separate the different modes and the Fourier spectrum extraction AM-FM mode function,the modal component of zero-sequence current of single-phase grounding fault in small current grounding system is extracted,and the low frequency modal component comprehensive correlation coefficient and high frequency energy of the zero-sequence current value selection implementation fault line.Finally,the validity and superiority of the proposed method are verified in the Matlab simulation software.