Abstract: After a large number of distributed power sources are connected to the distribution network, the dimension of the network structure and the uncertainty of the power flow direction when a fault occurs are increased. In view of the information distortion and the complexity of fault location when collecting or uploading fault current information, a fault location solution method is proposed, which establishes a mathematical model according to the network structure of distribution network, constructs a hierarchical model with the idea of hierarchical simplification, greatly reduces the variable dimension of distribution network, constructs a switching function and adds fault auxiliary criteria, and then improves the whale algorithm by population distribution, adaptive weight adjustment and cross-border treatment. The simulation results show that the proposed method can accurately locate the fault section and improve the efficiency and accuracy of distribution network fault solution under various working conditions, such as single fault, multiple faults, distorted current information or switching state of distributed generation.

Key words: distributed power supply, information distortion, hierarchical model, switching state, fault location