The Research On The Feeder Fault Location System Of Distribution Network And Design Of Intelligent Location Terminal Unit

The feeder fault location in distribution network is an important content of distribution automation, which has great influence on the reliability of power supply. The broad extension of distribution network and large amount of branches reduce to the difficulty of feeder fault location, especially location to the single-phase ground faults. Based on the research of existing methods of fault location in distribution network, two kinds of feeder fault location systems and the core equipment-intelligent location FTU (Feeder Terminal Unit) are designed in the paper. The location system advanced in the paper and the location FTU can meet the need of distribution automation. The research on the paper has theory significance as same as value of engineering practicality.According to the characteristics of the faults in the feeders of the distribution network, the K-fault diagnosis method of analog circuit diagnosis is employed in the feeder fault location in distribution network. The realization scheme of the application of K- fault diagnosis method is presented. Based on feeder fault location method of cooperation of reclosure and voltage-time sectionalizer, an improved voltage feeder fault location method is put forward. The method can realize fault section automatic location and separation in the conditions of all kinds of short circuit faults and single-phase ground fault based on the feeder intelligent location terminal, that is intelligent location FTU(Feeder Terminal Unit).Aimed at the shortage of current feeder fault location methods and the actual requests of distribution automation, the distributed and the combination of distributed intelligent and concentrated feeder fault intelligent location schemes are designed, which can be used in areas in different distribution automation developing phases. The combination location scheme can realize fault location regardless of the communication channel, with avoidance of the disadvantages of the over depending on communication of current feeder fault location methods.In the paper, the core equipment of the feeder fault intelligent location scheme-intelligent location FTU is designed emphatically. The FTU can not only be used to be the supervising and controlling terminal of distribution automation with generic functions, but also match the demands of special signal detecting. And it can realize both distributed and concentrated feeder fault location. In order to meet the demands of communication network construction in different areas, the intelligent location FTU includes RS485, CAN, Ethernet, GPRS communication interfaces, and it can accord with several communication protocols, so it has broad applicability.