Impact of negative sequence current of traction load on the grid running state

On the basis of considerable amount of measured wave-recording data of electrical traction load, this paper used the measurement-based method to establish models of negative sequence current source in different traction working conditions. The establishment of UDM in PSASP has enabled the information exchange between models of negative sequence current source and the harmonic analysis and calculation in PSASP. With WEPRI-36 nodes set as network background to conduct the simulation of grade operating state, this paper systematically analyze the influence that traction load has on a series of aspects like generator, transformer, line and relay protection by making comparison between simulation results of different traction transformers. Accordingly, corresponding measures are put forward.