The Research On Performance Analysis And Simulation Technology Of Traction Drive System

The high-speed electric multiple units (EMU) train has high operating speed and great traction power, so the operating characteristics of the traction drive system are very important. This thesis focuses on CRH2and CRH3traction drive system, their complete simulation models based on Matlab/Simulink are established, and then the simulation results are obtained. The results show the four quadrant pulse rectifier can realize the system unit power factor operation and DC bus’s voltage stability by adopting the transient current direct control. Three level modulation and double change carrier phase shift technology can reduce the current harmonics of grid side. With both the indirect rotor magnetic field orientation vector control (FOC) and direct torque control (DTC) strategy, the running speed and output torque have good tracking performance. To DTC strategy, the torque responses more quickly, but torque ripple is more obvious, especially below the speed of200km/h.Based on the simulation model, this thesis analyses the performance of the EMU train traction drive system with fluctuated voltage or in phase separations region. The results show that the train can quickly adapt to the voltage variations for ensuring the reliability of the traction system. According to four traction motors of one carriage in parallel operation, the load unbalanced distribution status is analyzed due to the wheel diameter deviation and motor parameters deviation, and then a suitable control strategy based on the weighted control method is proposed.The traction drive system simulation model is packaged as a dynamic link library files by rapid prototyping technology, and then the high speed train traction drive simulation software is developed based on the platform of Visual C++. It not only realizes the graphical, dynamic simulation of the train traction drive system, but also has interfaces with other sub modules. The friendly software interface, simple operation and accurate simulation results can provide a reference for optimization design and operation to the train traction drive system.