Single Phase-to-earth Fault Selection And Location Of Small Current Grounded System

The single phase grounding fault location is the focus which researchers pay attention to and study in the small current grounding power systems. With the improvement of aut- omatic level in distribution systems, the study about it is urgent daily.In this paper, the important point is the study about the application of wavelet analysis in single phase grounding fault location of small current grounding power systems, wav- elet transform is used as a novel tool of signal analysis to obtain useful fault transient components, a new criterion of fault line selection is constructed based on the time and frequency localization character of wavelet transform. The new criterion obtain the singular signal fully and exactly as the jumping-off place, take advantage of wavelet disposing the transient singular or faint signal, scarcity of the analyzing principle based on steady signal is fetched up and enhance the anti-disturb capability, so that it has higher reliability and accuracyArc–grounding fault line selection is the paper's key point and innovative point about small current grounding power systems. A lot of simulations are made based on the change rule and the character of fault voltage, fault current The simulation study declare that the use of the method of wavelet analysis can select the fault line when the arc-grounding fault take place, it will play a important directive role in the research of the protection equipmentThe fault location principle that utilizes traveling wave is used in the small current grounding power systems firstly in my paper. Using the powerful function of wavelet in the face of singular detection, the time that the wave Crest arrives are detected and the fault location is realized. This paper provides a new approach for the research of equipment of the single phase grounding fault location and makes a significant step for the improvement of automation level in the distribution systems.