A magnetic bearing system has been designed, fabricated and tested for high speed rotating machines. The system is composed of flywheel, magnetic actuators and their controllers. The five axis positions are actively controlled by the independent 5-channel PD controllers.
In this experiment a rigid rotor having mass of 3.3 Kg can be levitated and rotated up to rpm 11,500 for 10 minutes. Here, the operating time limitation is due to temperature raise of the rotor and motor, but not due to any defects of the magnetic bearing itself. The temperature raise of the rotor is assumed to be caused by the residual vibration of the rotor during rotation.