A Research On Single Phase Grounded Fault Locating For Power Network With Arc Suppression Coil Grounding System

With the advancement of intelligent power grid construction, State Grid's demand of setting high voltage transmission and distribution line monitoring range is more and more intense, but the traditional fault indicator by mechanical structure can unable to realize real-time monitoring. Line fault must be found and locating by artificial work. In the system of center ineffective grounding, it's difficult to achieve accurate locating of grounded fault which is the most important point that can't satisfy the needs of State Grid.In this paper, the method of small signal input which is the most stable and reliable is chosen to judge and locate line grounded fault through the research called way of fault indicator judging and locating. For wireless communication technology, GPRS technology is selected to be remote data interaction combined with the actual situation of Shanghai Power Grid, through the comparison of seven advanced ways which are commonly used. Based on fault judgment principle, a mathematical model of a short circuit and small current grounded fault is abstracted to be a criterion of line selection technology of single phase grounded fault in arc suppression coil grounding system.The new fault locating system developed on the base of the theories mentioned above can be used to detect the segment of line fault effectively. With the combination of fault selection software and fault indicators on-line, the position information of line fault can be given on PMS in a few minutes which can help the maintenance team get to the scene and remove the fault in the first time. In this way, the power-supply reliability can be greatly improved.