Interior Permanent Magnet Motors With Reduced Torque Pulsation

In this paper, three-phase interior permanent magnet brushless DC motors are analyzed. The effect of magnetization direction, number of stator slots, winding distribution, skew angle, current waveform, and advance angle on torque pulsation is examined. Finite element method is used to calculate the torque, reluctance torque, back iron flux density, tooth flux density, detent torque, and back electromotive force of the motors. Switching instants are calculated such that the reluctance torque can be utilized and maximum torque with reduced pulsation is achieved. Experimental results to support the simulation findings are included in this paper.