Development Of The Miniature Active Magnetic Bearing With 6 Concentrated Wound Poles

This paper introduces design and control of a miniaturized radial active magnetic bearing (AMB) aiming the improvement in durability and noise reduction of small motors. The purpose of this research is to develop miniaturized practical AMB so that it can be applicable to the small motor. The proposed AMB, which is inner rotor hetero polar type. Generally, the stator has 8 poles. However fewer pole numbers leads to lower cost of AMB, but disadvantage is low bearing force. In order to balance the cost and the bearing force, the pole number was set to 6. Then, the control of the bearing force is introduced. In order to reduce energy consumption, the minimum energy control method is developed. In this method, coil currents are calculated from a simple magnetic circuit so that the copper loss in a coil may become minimum. Finally, the prototype motor is fabricated using the proposed AMB.