Study of Rotational Stability in HTS Magnetic Bearing Rotor Incorporated the Secondary of the Induction Motor

Abstract

This paper proposes the study of rotational stability in HTS magnetic bearing rotor using the pinning force of the high temperature superconductor (HTS) incorporated the secondary of the induction motor. In this study, the designed rotor is rotated by the rotating magnetic field of the secondary of the induction motor (IM). The magnetic bearing rotor has the function of the secondary side of the IM. In order to verify whether this instability affects the levitation characteristics by the pinning force, the horizontal angle of the rotor during the rotation is measured. At that time, the rotational characteristics are measured. Vibration suddenly occurred at a low rotational speed after the power supply started. After that, the rotor rotated stably. The inclination of the rotor is suppressed by 37.4% when the levitation gap <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g</i> decreases. The pinning force increases as the levitation gap decreases. Therefore, the vibration suppressing effect of the rotor is obtained and the average angle is decreased. From the rotational experiments, it was confirmed the rotor with secondary of the IM function does not affect the levitation characteristics by the pinning force.