Unbalance compensation of magnetic bearings

In a rotational machine, unbalance of the rotor is formidable since it causes resonance synchronized with the rotation of the rotor. In order to suppress this unfavorable vibration, an active vibration control system, which accommodates changes of rotor dynamics is desired. In this paper we propose a vibration control system using active magnetic bearings to cope with a sudden sinusoidal disturbance, which simulates a turbine blade loss. Experimental results reveal that our vibration control system is effective enough to suppress the whirling motion of the rotor caused by a sudden disturbance