Self-Sensing Control Technique of Self-Bearing Motor

This paper introduces a self-sensing technique of self-bearing motor by using the differential transformer principle. This self-sensing technique has wide linear range than the other technique due to the use of the carrier frequency component. Therefore it is expected to have robust displacement information for the temperature fluctuation. This technique uses the structure of the motor and levitation coils which are similar to the differential transformer. In this paper, the fundamental principle is introduced how the self-sensing is achieved by the differential transformer principle. Then the differential output characteristics is examined experimentally. Finally levitated rotating test is carried out by self-sensing control.