| Consideration that about 80% of the total fault in distribution system is the single phase grounded fault, we should find fault line or feeder exactly and get fault location accurately after fault occurred. Only on that way, we can absolutely accerlate the technology in distribution system (DS). However, in DS the signal is too tenuous to detection because of the huge amounts of bifurcations and the complex system and so on, which make many devices cannot get right selection and location. With the rapid development in transmission system, many fault location methods can be used for reference. But if we use those methods directly without considering the charactertic of DS, we could gain invaild result.This thesis combines the matured-method in transmission network with the existing techniques of fault line selection by the charactertic in distribution network for getting the fault line or feeder exactly and get fault location accurately.We can use fault information by the fault recorders after fault occurred. First of all, use the impedance scheme to obtain a rough outcome. Secondly, utilizing traveling wave fault location and the correlation of figures, which are processed by the wavelet transform, find a maximum correlation figure with the first wave. Thirdly, the distance responds to the other figures with the first figure are used to compare to the network structure for exclusion the sound feeders and finding fault line. Last but not least, the duality of the fault line is used for checking the result.At last, the result of ATP simulation show that the algorithm proposed in this paper is accurate and possible. Using the method of figure correlation can get accurate fault location. Using the exclusion can get correct line selection, even check the algorithm whether can get right results. And using the method which combine impedance with traveling wave, can improve the robustness of result. So the proposed method in this thesis is good for market.
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