Adaptive filtering for unbalance vibration suppression

A method is introduced which suppresses the unbalance vibration of a rotor suspended by magnetic bearings, using two adaptive filtering techniques. The first filter separates the rotor displacement signal into rotation-synchronous and rotation-asynchronous components. The former signal can be cancelled by the output of the second filter, which allows estimation of the unbalance disturbance force using the impulse response of the plant of rotor with control system measured online under high-speed rotation. Both simulation and experimental results are shown to describe the basic and practical effectiveness of the proposed method. The system works well even when using only the initial part of the plant response.