An application of sensorless drive technology to a three-phase hybrid stepping motor drive

This paper presents a three-phase hybrid stepping motor drive system to which sensorless drive technology of brushless DC motors is applied. The drive system is characterized by measurement of back EMF in the motor windings. As a result, the drive system can damp rotor natural vibration of the three-phase hybrid stepping motor. Moreover, an acceleration and deceleration pattern is proposed to suppress undesirable transient vibration in acceleration, deceleration, and positioning operations. Some experimental results show that the experimental system can damp the rotor natural vibration even if the rotor inertia varies.