Fault Positioning Technologies In Low Current Earthing System Based On The Transient Signal

Fault of distribution system, especially single phase fault, it is an important subject to repair fault line、supply power reliability and be security and stability、operate economically. This paper explained scientifically the method that utilized intelligence terminal’s information to Fault positioning technologies in low current earthing system.Networks with ungrounded neutral are widely used in distribution system, it is an important subject on how to detect line fault especially single phase to earth fault in power system protective relaying. Through reviewing the relevant published documents, this paper summarizes all the existing theories to three types, including measuring fault distance on line’s terminal, injecting stated signal in power system to search fault point, and check fault information’s difference on fault point’s forward and behind to confirm fault section.Advantages and disadvantages of these methods are analyzed respectively, based on which the problems existing in the field are proposed. In the end, the research orientation and further development of fault location technique are discussed.An experiment caused by grounding fault initiated artificially is carried out. Travelling wave fault locator captures voltage signal and arriving time of travelling wave. And the distance of fault is given. Correction of the proposed method is proved.