Winding Design and Characteristic of a Consequent-Pole Type Bearingless Motor with 4-Axis Active Magnetic Suspension

Suspension winding design has been investigated for successful magnetic suspension under the limited voltage and current of suspension power electronics circuits. In bearingless motors, winding configuration design is a critical issue. To reduce requirements in suspension winding and its inverter, required current should be reduced. Thus, a large number of series windings with small diameter conductors is preferred. However, the current response in suspension winding becomes slow, and in the worst case, magnetic suspension is not possible. Design consideration of suspension winding is reported with experimental confirmation. Successful start up and operating characteristics are presented.