基于基波电流调控法的六相永磁同步电动机转矩波动抑制方法研究

Research on the Method of Reducing Torque Ripple for Six-phase Permanent Magnet Synchronous Motor(PMSM)Based on Fundamental Current Regulation

六相永磁同步电动机一相开路故障时,绕组中的三次反电势将与基波电流相互作用产生较大的转矩波动。针对六相永磁同步电机一相开路故障,以绕组铜耗最小为优化目标,故障前后转矩恒定分量不变和三次谐波电势产生的转矩波动最小为约束条件,建立拉格朗日方程,得到容错运行时相电流的最优解析解。采用数值方法对故障前后电机额定工作状态进行了仿真分析,验证了解析解的正确性。提出的转矩波动抑制方法可以通过调整基波电流的幅值和相位实现对三次谐波反电势所引起转矩波动的抑制,无需对非故障相绕组注入谐波电流,提高了多相电机的容错运行工程实用性。

During the one phase open circuit fault of the six-phase PMSM,the torque ripple was generated by the third back-EMF of the winding interacts with the fundamental current increased obviously.Aiming at the one phase open circuit fault of six-phase PMSM,the Lagrange function was built to obtain the optimal phase current in the fault tolerant mode.Taking the minimum copper loss of winding as the optimization objective,meanwhile,the constraints include that the constant component of torque in normal and fault mode remains unchanged,and the torque ripple producing by the third harmonic back-EMF is minimum.The most optimal results were given in fault tolerant mode.The rated parameters were analyzed by numerical simulation analysis which in normal and fault mode,and the results proved the correctness of the analytical solution.The proposed torque ripple suppression method can suppress the torque ripple caused by the third harmonic back-EMF through by adjusting the amplitude and phase of the fundamental current,and improved the fault tolerant operation engineering practicability of the multi-phase motor.