Vibration Control of a Multi-Disc Rotor System with Active Lateral Bearings and Disturbance Estimation

Abstract

A rotor system used in a wide range of engineering applications generally consists of a rotor shaft, multiple discs, blades and other essential components, generating a multi-disc rotor arrangement. System uncertainties caused by unbalanced discs and disc mass variation, compounded with external disturbances under different operating conditions, can lead to a variation in rotor-dynamic characteristics with multiple structural resonances, potentially causing an excessive level of rotor lateral vibration. Therefore, to effectively suppress lateral vibration for such a multi-disc rotor system, an active vibration control approach using active lateral bearings with disturbance estimation is presented in this work. The utilized active lateral bearings can generate necessary bearing displacement regulations to eliminate the bearing forces so to effectively control the lateral vibration of the rotor system. The disturbance estimation approach is used to estimate the unknown uncertainties associated with the system's internal dynamics and external disturbances affecting the rotor system, incorporating an extended state observer (ESO). Utilizing the total disturbance estimated by the ESO to cancel out the effects of the disturbance using active lateral bearings, the rotor lateral vibration can be satisfactorily suppressed with sufficient control robustness against uncertainties in the rotor internal dynamics, particularly associated with the degree of mass unbalance of rotor discs, demonstrating the effectiveness of the active vibration control approach for suppressing vibration in a rotor system.