Electric Traction Drive System Fpga Modeling And Hardware-In-The-Loop Simulation

Electric traction drive system localization has been one of the most important issue of China railway equipment. During the research and development of electric traction drive system controller, hardware-in-the-loop (HIL) simulation technology is a major method. It can ensure the safety and reduce the risk of test. However, the simulation cycle lasts long because of the current technology limit and the time compensation algorithm must be used to improve the precision. This dissertation simplifies the math model of electric traction drive system, integrates this model in the FPGA chip and realizes the high speed real-time simulation system.Firstly, the structure and principle of electric traction drive system are introduced. Switching functions are defined to describe the two-level and three-level topology structure and state equation are deduced for rectifier, DC-link circuit and inverter. In addition, asynchronous motor is also modelled by state equation in the two static dimensional coordinate system. Moreover, auxiliary variables are used to reveal the relationship between pulse signal of switching devices and switching functions for rectifier and inverter the converter have switching devices. Switching functions logical expressions based on mathematical logic are derived by the Mixed Logical Dynamical Model method. In this way, the Mixed Logical Dynamical Model of the two-level and three-level topology structure system is accomplished.Secondly, high speed computing characteristic of Field-programmable gate array (FPGA) is declared and System Generator, a FPGA development toolbox is emphasized for its advantage. And FPGA basic calculation realization is introduced in small scale. Besides, the discretization block diagram is presented separated by rectifier, inverter and asynchronous motor. Last, the time distribution scheme of pipeline is provided.Thirdly, common control algorithms, transient current control for rectifier and rotor field-oriented vector control for inverter are exhibited to satisfy HIL simulation need. As for two-level and three-level topology converter, sine-wave pulse-width modulation (SPWM) for rectifier and space vector pulse width modulation (SVPWM) are introduced.Lastly, the HIL platform is made up of DSP F2812 and RT-LAB OP5600 real-time simulator. After the comparison of FPGA model and CPU model, the result shows that the simulation step decreases by a large margin. In addition, FPGA simulation model is tested compared with models in Simulink Power System library under the same encourage condition and the test verifies the validity of FPGA model. Next, this model is under different operating mode test, which indicates high stability. The microsecond level real-time HIL simulation method improves the response speed and accuracy of the electrical traction drive system modeling. Moreover, it avoids complex compensation algorithm.