A New Method for Earth Fault Line Detection Based on Two-Dimensional Wavelet Transform in Distribution Automation

A novel method based on two-dimensional wavelet transform to detect single-phase faults in distribution systems is proposed in this paper. After structuring analytic signals of zero sequence current, the two-dimensional wavelet transform is applied. Thus the analysis of combined signal of amplitude and phase is realized. Compared with the use of single amplitude or single phase, combined signal carries more details of transient signal. Theoretical analysis and MATLAB based simulation show that the presented method can exactly and effectively choose the faulty line in single phase-to-ground fault.