Position-sensorless starting method and driving characteristics of closed-slot small permanent-magnet motor

This paper describes a method of estimating the rotor position of a surface permanent-magnet motor with a closed-slot stator for sensorless starting by using the effect of partial magnetic saturation. It also describes a starting scheme for the motor. Since the closed-slot stator is partially saturated at 12% of the rated stator current, this method reduces noise and vibration. Experimental results on the driving characteristics of the motor are also presented.