Research On Braking Energy Storage Of The Electric Vehicle With Permanent Magnet Synchronous Motor Based On Battery And Ultracapacitor

At present, all countries in the world is faced with environmental pollution and oil shortage problem. Taking electric energy as the power source, environmentally friendly, reducing dependence on the oil energy, electric vehicles get more attention of academia and industry. Motor and electric drive technology and battery technology is the key technology of electric vehicles. Currently the development of battery technology enter the bottleneck, in this case, one way is to use high-efficiency motors, electric drive technology to improve efficiency in the use of energy, the other way is to study motor brake feedback energy storage, which is not only an important vehicle energy management part, but also effectively enhance the energy efficiency of the electric vehicle and increase cruising mileage. As the main power source of traditional electric vehicles, the battery has low power density and cycle life. In comparison, the super capacitor has high power density and cycle life. Combining power battery and super capacitor together, the double power source structure can play their respective advantages, to achieve optimum combination under the existing technical level. This thesis is aimed to study on the PMSM driving and regenerative braking system for electric vehicles based on the battery and ultracapacitor.The main content of this thesis include the following five aspects:1. Analyze the working principle and mathematical model of PMSM, and measure the static characteristics of a three-phase 2.2kW PMSM.2. Design the PMSM drive hardware circuit and build a trailer platform to Simulate electric vehicles.. Design the SVPWM algorithm of PMSM, TMS320F28335 as microcontrollers, write control program of the PMSM driving system.3. According to the vehicle condition and energy flow requirements, analyze the topology of the selected bidirectional DC/DC converter, the working principle, further put forward the selecting principle of device models and parameters. Set up the related simulation, and analyze the simulation results in MATLAB/SIMULINK environment.4. Analyze the working principle of regenerative braking, establish the energy storage system of permanent magnet synchronous motor’s regenerative braking in MATLAB/SIMULINK simulation environment, analyze operating characteristics and simulation results of the system.5. Design and produce the bi-directional DC/DC converter system’s hardware circuit based batteries andultracapacitors, do the related experiments on the simulation conclusion. Build a hardware platform to analog braking energy storage of the electric car with permanent magnet synchronous motor, the hardware-in-the-loop simulation system ADI as the controller, to verify the proposed PMSM regenerative braking control strategy is correct and feasible.