基于谐波电流抑制的双三相PMSM容错型直接转矩控制

Dual Three-Phase PMSM Fault-Tolerant Direct Torque Control Based on Harmonic Current Suppression

针对六相PMSM电机直接转矩控制系统在缺相运行时存在的转矩脉动大和电流谐波大等问题,提出了改进方法。根据矢量空间解耦的思想,推导出电机缺相后的数学模型和电压矢量方程,通过方程画出缺相后的电压矢量在基波平面和谐波平面的分布,分析了电压利用率的问题,在利用原始矢量制作出电机故障前后共用一个开关表的基础上,加入虚拟矢量合成后减少电流谐波的想法,以减小电机在直接转矩控制系统中缺相运行时的转矩脉动和电流谐波。利用虚拟合成矢量制作出电机在故障前后共用的一个开关表。仿真建模并验证了该方法的正确性。

Aiming at the problems of torque ripple and current harmonics in the direct torque control system of sixphase permanent magnet synchronous motor,improvement methods were proposed.The mathematical model of the motor and the voltage vector equation with open-phase were derived according to the idea of vector space decoupling.The distribution of the voltage vector with open-phase was drawn in the fundamental plane and the harmonic plane according to the equation,and the voltage utilization rate was analyzed.On the basis of using the original vector to make a common switch table before and after the motor fault,the idea of the harmonics after the virtual synthesis vector was added,so as to reduce the torque ripple and current harmonics of motor with open-phase in direct torque control.The virtual synthesis vector was used to create a switch table that the motor shared before and after the fault.Simulation modeling was carried out and the correctness of the method was verified.