Modeling Simulation Of High Speed Railway Traction Power System And Harmonic Analysis

Compared with ordinary railway, high-speed railway is a faster means of transport.High-speed railway in China has developed rapidly in recent years; it makes electrifiedrailway put forward higher requirements on traction power supply system. Universally theelectric locomotives that run on high-speed railway are AC drive locomotives; thesingle-phase, non-linear, stochastic features of their loads are very obvious and may result inpower quality issues such as unbalanced three-phase voltage, harmonics and voltagefluctuations on grid public nodes. As main circuit of AC-DC-AC locomotive contains a lot ofnon-linear elements, and locomotive operation is complex, high-speed railway accessesindustrial frequency power from the grid, pumping a lot of harmonics into the public grid atthe same time. Harmonic is serious threat to traction power supply system and electriclocomotives; it will also affect the normal operation orders of high-speed railway. Therefore,to do high-speed railway traction load harmonics research for the future operation of railwayand design work is of great significance.Based on the first high-speed railway in China Beijing-Tianjin intercity railway, variouscomponents of the traction power supply system are studied carefully in this thesis, afterabstracting and simplifying the whole traction power system simulation models andCRH3-unit model of EMU traction drive system have been built on MATLAB/Simulinksimulation platform. After several simulation tests, currents of traction system are capturedand carried out by Fast Fourier Transform Algorithm analysis, getting the harmonic currentscontent and the distribution of initial phase angles. And correlation analysis program is coded byLabVIEW to get the linear correlation and formula between harmonic currents content andtrain speed. Finally the probability distribution laws of harmonic current initial phase anglesare analyzed by Monte Carlo method. Results of this thesis provide a simulation platform forpreliminary design work for the future high-speed railway and provide a reference for tractionpower supply system harmonics governance and filter design installation.