Suppression Method of Harmonic Disturbance Caused by Misalignment in MLRMS Using Improved Fractional-Order Repetitive Controller

In a large magnetic levitation rotating mechanical system (MLRMS) with multi-span rotors (MSR), the misalignment of the coupling will disturb the safe operation. To compensate the interference caused by misalignment of the coupling, a rotor disturbance suppression method using a resonant controller based on parallel fractional order repetitive control is proposed. In this paper, the mathematical model of coupling misalignment disturbance is established, and the influence of unbalanced mass is investigated. The stability analysis of the system with proposed disturbance suppression algorithm is carried out. The simulation results show that the method can effectively suppress the disturbance of unbalanced mass and misalignment.