电动汽车用永磁同步电机的弱磁控制策略分析研究

Analysis and Research on the Flux-weakening Strategy of Permanent Magnet Synchronous Motor for Electric vehicle

对于电动汽车的驱动电机来说,功率密度和转矩-转速特性是衡量电机运行性能的重要指标,而电机在弱磁扩速的过程中,随着转速的不断升高,电机的转矩和效率都会明显下降,进而影响了电机的运行性能。针对这一问题,本文基于最大转矩电流比算法原理以及永磁同步电机弱磁原理,提出在电机处于深度弱磁时采用定子电流最优控制策略,以保证电机在深度弱磁阶段能充分利用定子电流,使电机在深度弱磁阶段仍具有良好的特性。通过Simulink模型进行仿真计算,验证理论分析结果。研究结果表明,该方法具有一定的可行性。

For electric vehicle drive motor,power density and torque-speed characteristic are important indicators to measure the motor operation performance,but when the motor is in the process of flux-weakening,with the increasing of the speed,mo tor torque and efficiency will be significantly lower,which will then influence the performance of the motor.Aimed at this problem,based on the maximum torque per ampere algorithm and permanent magnet synchronous motor magnetic principle,when the motor is deep flux-weakening,the magnetic stator current optimal control strategy is used in this paper,which ensures the motor in deep flux-weakening can make full use of the stator current,and also with good performance Simulink model was established for simulation calculation.The results indicated that the method has certain possibility.