Study On Vector Control System Of AC Drive Motor For HEV

As a novel technology of automotive industry, Hybrid Electric Vehicle (HEV), which can reduce automobile exhaust and fuel consumption and optimize energy structure, has a widely foreground and becomes a focus increasingly. Drive motor and its control system are the core of HEV. They decide mostly on vehicle's dynamic behaviour. So it has theoretical and practical value to study on them.This paper studies the control system of AC drive motor used for HEV. The system adopts Field Orientated Control (FOC) strategy with high performance Digital Signal Processor (DSP) as a core. And an AC drive motor controller based on DSP is developed. The main tasks are included in the paper as follows:Firstly, the paper analyzes the development of HEV at home and abroad and carries on comparation of several drive motors. AC induction motor is choosed for HEV and FOC technology is proposed to develop the project according to the requirements of HEV driver.Secondly, with the dynamic mathematical model of asynchronous motor, the paper sets up a current model to calculate rotor flux position to decouple components between torque and magnetic field of stator winding current. The structure diagram of vector control system of HEV drive motor is given combining vector control theory with SVPWM technique.Lastly, a main circuit is designed aiming at a 5kw AC induction motor. The system control circuits are designed around TMS320LF2407A DSP and made up of current, voltage, speed etc detection modules and CAN communication module. The software implementation by assembly language is debugged on the CCS2 IDE platform. A fully digital control system is realized on HEV drive motor. The debugging results of motor's real operation are given and analyzed in the end of the paper.The experimental results show that this control system has haracteristics of fast response, efficient voltage utilization and fine dynamic behaviour. It can meet the dynamic and static requirements of HEV drive motor. It confirms practical value of application on low-cost and high-performance drive mtor control system.