Development of Magnetic Bearing Wheel (MBW) with Inclined Magnetic Poles (1st Report, Magnetic Bearing Control and Compensation of Surface Distortion of Sensors and Magnetic Poles)

A Magnetic Bearing Wheel (MBW) with inclined magnetic poles is under development, which enables the 5-DOF magnetic bearing to be composed of six electromagnets and thus to reduce the size and the weight. This paper deals with the control method and the surface distortion compensation of the sensors and the magnetic poles of the MBW. In general, the control of electromagnetic force of magnetic bearing with inclined magnetic poles tends to be complex. Based on a geometric analysis of electromagnetic force and magnetic bearing force/moment, a synthesis of simple magnetic bearing controller is proposed, which utilizes redundant freedom of electromagnetic force in order to satisfy a certain restriction on the magnetically suspended system and to optimize bias electromagnetic force. Next, a compensation method of the surface distortion of sensors and magnetic poles, which induces force/moment disturbance of the MBW, is presented.