The Design Of Controller For Electric Smart Car

With the development of science and technology, people’s consumption of coal, oil, natural gas and other fossil fuels is growing, and was followed by the energy crisis and environmental pollution problems. In order to reduce environmental pollution caused by burning fossil fuels, electric car and related technologies research has become a hot trend of the world.In this thesis, a brief introduction of the status of research and development of electric cars at home and abroad. It analyzes the driving principle and structure of the existing power system of electric cars. Electric cars of this study use pure electric, single motor, rear-wheel drive centralized structure mode. The functional requirements of the car controller are defined. Car control signals are analyzed to determine the CAN bus as a communication car controller configuration program.Secondly, a more detailed analysis driver’s operation intention of the car under different working conditions. The operating state of the electric car driving mode is divided into seven, and developed a corresponding control strategy for each driving mode. Determining electric car braking and regenerative braking by mechanical combination of braking, developed a corresponding control strategy. Based on CAN bus communication technology, developed a two-car CAN communication topology. Study on the power lithium battery and super capacitor, the lithium battery charge and discharge characteristics were studied, we designed a variable-capacity lithium battery. We designed a hybrid power system of super capacitor+ lithium battery, develop a more detailed plan of energy flow depending on the work status of the power system. Developing a renewable energy recovery solution that super capacitor recovers the main energy and lithium batteries recover part of the energy.Finally, controller hardware circuit was design based on the completed car STM32F205ZET6 chip, including:minimum system circuit, a power conversion circuit, data processing circuit, a communication circuit. Completed car controller software design, including:the system main module self-test, the drive control, brake control, CAN communications. Preliminary simulation and experiments show that this thesis the car controller design feasible.