车用永磁同步电机最大转矩电流比控制研究

Research on Maximum Torque Per Ampere Control of Permanent Magnet Synchronous Motor for Vehicle

基于d,q转子坐标系建立了永磁同步电机的数学模型,对比分析了经典的矢量控制方法。与控制逻辑架构简单、且易于实现的I_(d)=0控制方法相比,最大转矩电流比(MTPA)控制可以充分利用磁阻转矩,减小输出相同转矩下所需电子电流,提高控制系统的效率。弱磁控制通过改变调整交直轴电流来削弱永磁体磁场,使永磁电机能够运行在更高的转速范围。为了实现对交直轴电流的独立控制,提高系统的动态性能,需要进行电流解耦控制,并且分析了反馈解耦的实现方式和特点。将MTPA控制、弱磁控制、电流解耦控制三者结合,可以实现永磁电机在多种工况下的稳定运行。

The mathematical model of permanent magnet synchronous motor(PMSM)was established based on the d and q axis rotor coordinate system,and the classical vector control method was compared and analyzed.Compared with the control method of I_(d)=0 which was simple control logic structure and easy implementation,the maximum torque per ampere(MTPA)control can made full use of the reluctance torque,reduced the stator current required under the same output torque,and improve the efficiency of the control system.The flux weakening control weakened the permanent magnet magnetic field by changing and adjusting the d and q-axis currents,so that the permanent magnet motor could operate in a higher speed range.In order to realize the independent control of the d and q-axis current and improve the dynamic performance of the system,the current decoupling control was required,and the realization methods and characteristics of the feedback decoupling were analyzed.The combination of MTPA control,flux weakening control and current decoupling control realized the stable operation of permanent magnet motor under various working conditions.