Research on Fault-phase Selection of New High-Speed Railway Continuous Power Line Based on Wavelet Transform

On the basis of constructing a new high-speed railway distribution network structure, according to the actual operation of Xi-Cheng passenger dedicated line, a simulation model of power cable continuous line between two distribution stations is built on MATLAB / Simulink platform. Based on this model, the operation status of the system connected with power electronic transformer is simulated and analyzed, and a low-power experimental platform is built for experimental verification. The method of high-speed fault-phase selection of transmission line based on wavelet transform is applied to fault-phase selection of new high-speed railway continuous power line. In this method, the detected transient fault current is transformed into a module component through the phase-mode transformation, and binary discrete wavelet transform (DWT) was carried out on the fault current mode component by using db5 wavelet basis in MATLAB wavelet toolbox, then the maximum modulus was obtained as the phase selection criterion for phase selection. According to the characteristics of the continuous power line and the simulation results, the phase selection criterion is modified and improved. A large number of simulation experiments show that this method can realize phase selection under different fault types, different fault distances and different fault grounding resistance in new high-speed railway continuous power line.