Influence of Rotor Position Error on the Torque Performance of Doubly Salient Electro-magnetic Motor Drives

Precise rotor position information is needed in the doubly salient electro-magnetic motor (DSEM) drives to realize desirable torque performance. In this paper, the influence of the rotor position error on the current and torque performance of the DSEM drives are analyzed respectively. The mathematical model of the reference current as a function of the rotor position error is deduced. The simulation results show that rotor position error causes the fluctuant reference current and significant current tails. The relationship between the rotor position error and the amplitude of the current tails is also given. Consequently, the erroneous rotor position leads to serious torque ripple and less torque output capability.