Self-adaptive transient segment of SLG fault location in neutral non-effective earthed system

The duration of single-line-to-ground (SLG) fault transient signal is greatly influenced by the fault resistance in neutral non-effectively earthed power distribution system. This paper presents a method using the effective segment of transient signal identified by the magnitude of transient signal adaptively for SLG fault location. Therefore, available fault location method can adjust the length of the effective transient signal segment based on the fault cases. The advantage of the presented method is that it can make full use of the transient signal and the accuracy and robustness of the result can be enhanced. In this paper, the location principle is deduced and different approaches are introduced to extract the charge signal, including real wavelet transform, complex wavelet transform and S transform. The validity of the algorithm is studied within MATLAB Simpowersystem environment and the results show that S transform has better accuracy for SLG fault location.