Studies On Online Fault Locating Method For Multiple Branch Complex Distribution Networks

The online fault location technology for Distribution networks has the vital significance to research. It can not only reduce the outage time to achieve resume power supply fast, but also is a key part of smart distribution networks to achieve self-healing control.The majority of distribution networks are characterized by having several laterals, nonsymmetrical lines and time-varying loads, so in this paper, it firstly gets all node voltages and the line currents through pre-fault three-phase power flow calculation, and sets up the equivalent models of distribution network, at the same time has load compensation to reduce the impact of load fluctuation on the equivalent models. Secondly, an online fault location method for multi-branch complex distribution networks is proposed. When a certain fault occurs in the network, on the basis of the already known fault type and fault phase, and according to the real-time data of the voltage and current value recorded from the feeder, fault location algorithm is executed to determine the fault section and the fault point. Thirdly, using the simulation software PSCAD,16nodes and IEEE123nodes simulation model has been established for the research of the fault location. The effects of the fault resistance, the fault distance and the load variation on the proposed method are analyzed. Finally, the proposed method has been improved, a fault location method for distribution network based on line current measurement unit has been proposed, the effects of the fault resistance, the fault distance and the load variation on the proposed method are also analyzed.