永磁同步电机直接转矩控制不合理转矩脉动

Unreasonable torque ripple of direct torque control in permanent magnet synchronous motor

针对永磁同步电机直接转矩控制转矩脉动问题,依据永磁同步电机直接转矩控制理论,建立了永磁同步电机直接转矩控制系统模型,并分析了电压矢量对转矩的作用,得出以下结论:当定子磁链幅值与转矩角变化矛盾时,一定条件下转矩变化与定子磁链幅值的变化一致;此时传统开关表选择的电压矢量对转矩的实际作用与系统期望值相反,从而产生了不合理的转矩脉动。仿真结果验证了理论分析的正确性。

In order to decrease torque ripple of direct torque control （DTC） in permanent magnet synchronous motor （PMSM）, the PMSM DTC model is set up and the effect of voltage vectors on torque is analyzed based on the theory of DTC in PMSM. The conclusion that the changes in the magnitude of stator flux and torque angle （ angle between stator and rotor flux vector） is opposite under some conditions（ the change in torque is consistent with the change in the magnitude of stator flux）, is proposed. The actual effect of voltage vectors on torque based on traditional switching table is opposite to the expectation and causes unreasonable torque ripple. The simulation shows that the conclusion is correct.