Design And Implementation Of Electric Vehicle Controller

With the price of fuel keeping rising, and increasing concern about the environmental problem, Electric Vehicle (EV), which is characterized as safe, and reliable and clean, becomes a significant research and development direction of future vehicles. With its large starting torque and overload capability, series wound motor satisfying the demands of EV's quick start, acceleration, hill-climbing and frequent start or stop, is popularly used in EV driving around the world. This thesis mainli study on the series wound motor for EV and its control techniques and implemented the regenerative braking functionality. Based on the study, a highly intelligent, high-performance, safe and reliable EV controller was developed.Because field windings and armature winding are in series connection, full-bridge chopper for typical DC motor to achieve regenerative braking is not applicable for series wound motor. This thesis designed a new DC chopper based on popular DC chopper, which is not only capable of regenerative braking, but also can be used with series wound motor and other DC motor.The selection of the components in power circuit loop is first described. Then the simulation about the snubber circuit is performed, which assists in determining the sunbber circuit type and its parameters. The calculation on the power loss of chopper circuit follows, which provides a basis for the thermal design of the controller. The whole controller is implemented on a DSP. The hardware and software system are described in detail. Variant protection measures are adopted to ensure the safe and reliable operation of the controller.The thesis finally presents the test results of the controller. It shows that the controller can achieve regenerative braking, and can perform the functionalities of EV control well, with good robustness and stability.