The Interval Localization Method For The Fault Of Distribution Network

The diversity of failure causes the miss trip or maloperation of device and the incompleteness of information transmission makes the fault addressing for distribution network more difficult.Taking fault indicator as fault acquisition device, and using GPRS and radio frequency communication to send the data to the center of fault addressing system. In this paper, the signals of fault indicators and protection relays are adopted as condition attributes, and used the arithmetic that based on the combination of Rough Set theory and the Boolean calculation, to refine the rule to diagnosis fault. According to the distribution network, this paper uses depth first search method to confirm the route from the power point to the fault points; and uses breadth first search method to make local search to each fault points to find the fault indicators which are around the points. According to the distribution network and the rule which is refined, this paper confirms a fault diagnosis decision table and its reduction of the original decision table. On this basis, a two-steps arithmetic and a hybrid search algorithm are presented, which uses the fault diagnosis decision table and its reduction of the original decision table.The simulation results indicate that the new arithmetic not only improves the speed of fault diagnosis, but also enhances the fault tolerance and accuracy of fault diagnosis. It is able to satisfy the requirements of fault diagnosis for distribution system and is very suitable for large-scale distribution network.