Simulation Research On Electric Traction Drive System

At present, our country rapid develop CRH high-power AC driving electric locomotive. In this background, the paper first introduces the development of the electric locomotive at home and abroad, and the advantages of AC driving compared with DC driving. Second, based on traction drive system of HXD3type electric locomotive, expounds technical characteristics and circuit theories of electric traction drive system. Last as well as inverter and traction motor circuit, four-quadrant rectifier circuit is simulated and analyzed.The four-quadrant rectifier applies to main converter of electric traction drive system, and its control method is PWM technology, which can achieve that power factor approach1. The paper analysis structure and principle of four-quadrant rectifier circuit, design control strategy, choose parameters of main circuit based on HXD3type locomotive, used Matlab/Simulink to built simulation models of four-quadrant rectifier circuit and six group rectifier circuits in parallel which are carrier shift, simulate rectifier working. The simulation results are that the rectifier’s output voltage quickly reach the set value, current’s phase on line side is the same as voltage’s, the power factor close to1; the AC side current waveform of six group rectifier circuits close to sine, which has little harmonic and lower influence for electrified wire netting. So that four-quadrant rectifier have high power factor, less pollution for the railway supply network, it is an excellent power electronic rectification device.The inverter and traction motor circuit employs bridge three-phase inverter circuit, traction motor employs the slip vector control, which belong to indirect vector control, slip calculation depends on motor parameters. Motor parameters of HXD3type locomotive are unknown, so use common motor model to simulate for vector control. Use Matlab/Simulink to built simulation model of the inverter and traction motor circuit; simulate motor’s start working condition. The simulation results are that the speed of the motor quickly reached the set target maintaining constant torque; slip vector control system although has a simple structure, can quickly adjust torque, improve the motor start and anti-slip capability, has well control performance.In design of which, traction drive system of CRH high-power AC driving electric locomotive, should firstly test the structure, performance, parameters and possible faults of system by simulation in circumstance of approaching actual. So that can shorten the development cycle, maximum simulate the fact of system. Simulation and analysis have important significance for designing electric traction drive system.