航天机电作动器中双三相永磁同步电机优化设计

Optimal Design of Dual Three-Phase PMSM for Electromechanical Aerospace Actuator

谐波可以应用于多相电机的相电流和反电势中,以提高其输出转矩的能力,但这种增加只适用于谐波阶数低于7阶的情况。与5次谐波和7次谐波注入相比,3次谐波注入可以有效提高双三相永磁电机的输出转矩,且不会产生转矩脉动。针对双三相电机相电流和反电势注入3次谐波以提升输出转矩进行了理论分析。同时对驱动系统进行改进,将每套绕组的2个孤立中性点分别连接到电容器的不同中点,为3次谐波电流提供流通路径,使2套绕组之间的电流达到平衡。并且提出了一种新的永磁体塑形方法,综合考虑定子齿槽效应、铁芯饱和以及齿尖、极间漏磁,得到了最优的类正弦反电势。类正弦电流与类正弦反电势相互作用,电机的输出转矩提升了18.2%,且转矩脉动没有增加。最后,通过有限元分析和样机实验验证了理论分析的正确性。

Harmonics can be applied to the phase current and back EMFs of multi-phase motors to improve the torque output capability,but this increase is only applicable when the harmonic order is lower than the seventh order.Compared with the fifth harmonic and the seventh harmonic injection,the third harmonic injection can effectively improve the output torque of the dual three-phase permanent magnet motor without generating torque ripple.In this paper,a theoretical analysis of the phase current and back-EMF injection of the third harmonic to increase the output torque of the dual three-phase motor is carried out.The drive system is improved by connecting the two isolated neutral points of each set of windings to different midpoints of the capacitor to provide a flow path for the third harmonic current to balance the current between the two sets of windings.A new permanent magnet shaping method is proposed,which takes into account the stator cogging effect,iron core saturation,and magnetic leakage between tooth tips and poles,and obtains the optimal quasi-sinusoidal back EMF.The optimal quasi-sinusoidal current interacts with the optimal quasi-sinusoidal back EMF,and the output torque of the motor is increased by 18.2%under the condition of constant torque ripple.Finally,the correctness of the theoretical derivation is verified through finite element analysis and experiments.