一种基于MTPA的IPMSM弱磁控制系统

A Flux Weakening Control System of IPMSM Based on MTPA

内置式永磁同步电机,其速度运行范围与电机参数息息相关。本文从电机本身参数的角度出发,充分考虑电机实际运行的两个约束条件:电压极限椭圆和电流极限圆,对实验室电机进行分析,提出了一种基于MTPA的弱磁控制算法。在低速区,利用曲线拟合,解决了MTPA控制算法中d、q轴电流给定值无法获得解析解的问题,得到了不同转速要求时的交直轴电流给定值。在高速区,利用转矩的梯度和电压差对MTPA指令进行修正,对电机进行弱磁控制。理论、仿真和实验结果表明,在特定电机参数下,i_d=0的矢量控制无法使电机达到额定运行状态,而本文所提出的基于MTPA的弱磁算法,既满足了电机的额定运行状态,同时提高了电机的带载能力,拓宽了电机的调速范围。

The speed of interior permanent magnet synchronous motor is closely related to the motor parameters. In this paper, from the angle of the parameters of the motor, the two constraints of the actual operation of the motor were fully considered: voltage limit ellipse and the current limit circle. The laboratory motor is analyzed, and a weak magnetic control algorithm based on MTPA was proposed. In the low speed region, by using the curve fitting, the question of given value of the axis current can t be obtained in the MTPA control algorithm was solved and the given value of the d -axis and q -axis current was obtained at different rotational speed. In the high speed region, the MTPA instruction was corrected by torque gradient and voltage difference, and the motor was controlled by flux weakening. The theory, simulation and experimental results show that the vector control of i d =0 can t make the motor reach the rated operating state under the specific motor parameters, and the proposed MTPA based weak magnetic algorithm not only satisfies the rated operating state of the motor, but also improved the carrying capacity of the motor, and broadened the speed range of the motor.