Research Of Traction Drive System Simulation Platform Based On RT-LAB For High-Speed Train

In recent years with the rapid development of high-speed railway in China, the scale of the investment and construction is larger and larger. The traction drive system, as the important component of high-speed EMUs, is not only a direct source of power which is required by the EMUs, and it’s also the key links to promise the EMUs to have a fast, safe and stable operation. The program which is undertaken by the laboratory is based on the structure and parameters of CRH3high-speed EMUs which are extensively researched currently. Use Matlab/simulink graphical simulation tools and RT-LAB software package to build traction drive system simulation model. Under the environment of train communication network, RT-LAB target emulator which is downloaded with compiled simulation model, cab console and external controller make up the traction drive semi-physical simulation system.Traction converter is the core control part of the traction drive system simulation model, it contains rectifier, intermediate DC voltage regulator circuit and inverter. The rectifier uses the four-quadrant pulse rectification control mode, its rectification and inversion during traction and braking conditions can ensure the rational use of energy. Filter and constant-voltage capacitor included in the intermediate DC voltage regulator circuit ensure the stability of the DC voltage. Compared with the vector control mode of actual EMUs, the inverter uses the direct torque control mode. It does not have a complex coordinate transformation and the rotor parameters don’t affect the estimate electromagnetic torque during the traction motor running. The control is simple and effective. The external controller mainly receives the control signals from communication network in order to achieve the traction control strategy algorithm. And it also receives the signals from the emulator to monitor the data for the console. After the entire semi-physical simulation system has been structured, the control signals are transferred through the train communication network and received by external controller to finish the control algorithm. After that, the signals are sent to the RT-LAB emulator to complete the entire operation of the traction drive system. During the operation, the amount of the relevant signals of the traction drive system simulation model can be transferred to the console through the external controller and the train communication network. Then the cab can monitor the entire operation real-time and make adjustments to the unexpected situations in time.Use the built traction drive semi-physical simulation system to simulate the operation of different working conditions. The results of train speed curve are smooth, the ripple of stator flux and electromagnetic torque in traction motor is also small. In addition to the operation simulation of switching in different working conditions, the system also simulates the fault operation conditions of the voltage fluctuations or power-down, and part of the lack of traction power. The analysis of fault simulation results shows that, when the duration of faults is short or the fault conditions are in the system allowable range, the train will quickly recover to the normal conditions after the faults are immediately removed. This provides a theoretical basis for the system to add fault diagnosis module in the future.