Synchronous disturbance attenuation in magnetic bearing systems using adaptive compensating signals

New adaptive vibration control algorithms are developed for minimizing selected vibration performance measures by adjusting the amplitude and phase of a synchronous signal injected at the summing junction of the magnetic bearing feedback control loop. Two methods have been investigated. One is the application of the filtered-x adaptive filtering techniques to directly attenuate the magnitude of the rotor displacements or currents and this will be referred to as a direct method for synchronous disturbance attenuation. The other method minimize the magnitude of the magnetic bearing system error signal and will be referred to as an indirect method for synchronous disturbance attenuation. The developed algorithms have been experimentally tested and the results showing the effectiveness of the algorithms are reported