Abstract：For the torque ripple of dual-stator low-speed high-torque permanent magnet synchronous motor, this paper studies the influence of the slot number combinations and the relative position of inner and outer stators on the torque ripple of dual-stator permanent magnet synchronous motor based on the phase analysis. The whole motor is divided into inner and outer motors by the superposition principle, and the torque ripple is studied separately. When the slot numbers of the inner stators and outer stators are different, by analyzing the back EMF, it is found that the positive and negative harmonic winding factors will affect the phases of the back EMF of the inner and outer motors. Based on this, the phases of the back EMF of the inner and outer motors are predicted, the respective ripple torque phases of the inner and outer motors are further predicted, and the influence of the inner and outer motors' ripple torque phases on the whole motor ripple torque is analyzed. When the slot numbers of the inner and outer stators are the same, based on the torque model of the back EMF and currents, it is demonstrated that the relative positions of the A-phase axis of the inner and outer stators will affect the torque ripple of the whole motor. The finite element simulation verifies the above theoretical predictions.
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2022, Vol. 37 
