Research On Open-end Winding Asynchronous Motor And The Fault-tolerant Control

With car ownership is increasing rapidly in China, the problems of huge oil consumption lead to the oil resources drying up and serious air pollution. Therefore, developing the electric vehicles will be significant. Asynchronous motor is cheap, simple structure and reliable, so it is widely used in the electric vehicles. At the same time open-end winding has the same output voltage ability with the three-level inverter, and has a unique fault-tolerant ability, has started to use in electric vehicles in recent years. However, motor drive system is directly related the personal safety, thus improving the reliability of control system is important, and research should be done on the fault-tolerant control about the open-end winding asynchronous motor.Based on analysis of the open-end winding asynchronous motor structure, the mathematical models in different coordinate are built. According to the mathematic model in two phases rotating coordinate the MATLAB model of open-end winding asynchronous motor is established. Research has been done on open-end winding asynchronous motor based on rotator field oriented. Considering the zero sequence voltage and zero sequence current of the single power supply open-end winding system, corresponding suppression methods are presented. It gives the inverter and winding fault identification method. And guaranteeing the space voltage vector of fault unchanged, the control method is given to realize fault tolerant control. For double power supply system, suppression of common mode voltage is researched. On the basis of fault identification, two phase fault tolerance and three-phase fault tolerant control system is compared. Simulation model is built by MATLAB/Simulink to verify the theory above.Considering the open-end winding asynchronous motor and fault-tolerant control system, the control system chooses the Freescale's DSP chip MC56F8346 as the core of the system, and the hardware and software design of the system are completed, and relevant experiments are completed. The experimental results show that the feasibility of the open-end winding asynchronous motor vector control is proved by the experiment, and realize fault tolerant operation of the inverter and winding fault.