Analysis and Control of a Three-Pole Permanent Magnet Type Bearingless Motor

The active magnetic bearing (AMB) possesses several advantages such as no friction, high rotational speed, less energy loss, and long life span etc. In rotation application, however, it must be connected to a motor, which may degrade its performance. Bearingless motor is the combination of the active magnetic bearing and motor. It saves software and hardware facilities, resulting in lower costs. This paper mainly designed a three-pole permanent-magnet type bearingless motor, and analyzed the rotational magnetic field, magnetic force of the bearing, and resulting torque of the motor. Finally, we established system dynamic mathematical model. The controller design and numerical simulations are implemented, and reach the last target.