An accurate fault location method of smart distribution network

In order to deal with the global energy crisis and environmental problems, development direction of electric power industry in the new century has become a hot issue of global concern. The smart power grid concept has come into being as the times requires. Smart distribution power grid is an important part of the smart power grid, its core objective is to realize the self-healing distribution power grid. Smart distribution power grid self-healing control technology is one of the smart distribution power grid related problems, which are urgent and need to be focused on. The after fault self-healing control technique is an important content of research on control technology of the smart distribution grid self-healing. By intelligent means, after fault self-healing control technology can realize fault diagnosis, fault location, fault isolation and blackout areas fast restoration of power supply, with no or only a small amount of manual intervention, to achieve fast response, fast processing of distribution power grid fault and fast recovery. Based on the optimization of the network reconfiguration, as much as possible fault without losing load, or as little as possible loss of load, in order to achieve fast processing fault, reduce the fault processing time, reduce load power cut area, increase the reliability of the distribution power supply. One method of distribution power grid fault diagnosis and location uses fault detection signal uploaded by FTU installed on feeder column switch and DTU installed in power distribution room, and combines with distribution power grid state when fault occurred. Another method uses fault detection signal uploaded by fault indicator installed on switch and combines with distribution power grid state when fault occurred. An accurate fault location method is proposed in this paper, which uses the fault signal sent by FTU, DTU and fault indicator installed on switch, and combines with distribution power grid state when fault occurred. The method in this paper, defines a unified network topology model of the FTU, DTU or fault indicator installed on the switch and the fault indicator installed in feeder segment. Based uploaded fault signals and topology information when distribution power grid fault, it can do fault diagnosis and precise fault location, and can get accurate fault position between the tower which the fault indicator is installed on. An accurate fault location method proposed in this paper is suitable for overhead lines, cable lines and overhead cable mixed lines and other wirings, suitable for FTU, DTU and fault indicator mixed installation situation, adapts to the actual situation of Chinese distribution power grid, has the characteristics of strong adaptability and easy to use.