Earth Fault Location In Non-solidly Earthed Network For Distribution Network

With the development of national economy, the requirement for power distribution reliability becomes higher and higher, so the reformation and improvement of the power system are needed, especially the traditional network. The smart grid is the trend of future network. Self-heal and fast self-heal is the key function to the development of smart grid. Because of the special operation characteristics, non-solidly earthed network (isolated, Petersen coil compensated or high resistance earthed) is operated in distribution network. It can improve the self-healing performance. In distribution network, the faults are mostly single phase to ground faults, immediately 80%, so fast location becomes the focus of power system. Now some of the fault location methods are used in practice, but the success rate is low as a result of weak singles and the limitation of detection methods. So it is needed to research. For the fast and reliable location of single phase to earth fault, this paper combined the disadvantages of existing location methods and proposed a location method which can used in practice and can realize the fast and reliable location in order to reduce the economic loss.This paper proposes the basic principle of fault location and the design scheme of fault detection. It combines the fault line selection and location to realize the fault location. Firstly, it is needed to determine the fault line; secondly, the data of fault line will be uploading to fault location system by GPRS wireless network, so it can determine the fault section according to the fault location method. By this method, it can realize the fault point quickly and isolate the fault accurately. So the economic loss will be reduced.Compared with the traditional fault location, this paper combines the fault location methods for single phase to earth fault and the method which combines with the stable and transient information is used for fault location. This can utility the advantages of fault location based on stable information, such as simple calculation, high reliability, location repeatedly and so on, the most important is that it can applicable to the Petersen coil grounding system.. Finally, it only analysis the data from the fault line, so it can sane time and resources. It will be used broadly in the future.