Motor drive for a novel high-speed micro-milling spindle

This paper focuses on integration of a permanent magnet motor with active magnetic bearings for driving a high-speed micro-milling spindle. A new concept of supporting a short rotor with a slotless PM motor embedded by 5DOF bearings is conceived. In the concept, the bearings and motor functions remain independent. A 100 W, 200000 rpm motor compatible with magnetic bearings was designed and manufactured. An additional setup with aerostatic bearings was also constructed for testing of the motor.