A novel optimal control strategy of turn-on angle and turn-off angle for doubly salient permanent magnet motor

Doubly salient permanent magnet (DSPM) motor suffers severe torque ripples when the motor operating at control strategy of standard angle because three phases are turned on or turned off at the same time. On the base of applying finite element analysis method to DSPM motor, the cause of torque ripple is analyzed in detail. A novel optimal control strategy is proposed in order to reduce commutation torque ripple. And conduction angle of upper power devices of inverter is advanced and conduction angle of lower power devices is delayed. The conduction mode of power devices is subdivided in commutation area. And there is a transition between conduction mode of two phases and three phases. The torque ripple of motor is reduced and the total torque is increased at commutation area. A simulation model of DSPM motor is built according to the value of flux linkages and inductions. The validity of the novel control system is verified by simulation and experiment. The low speed comparison between the law of standard angle control and novel optimal control through experiments indicates that the novel optimal control strategy can reduce torque ripple greatly.