Disturbance-observer based control for magnetically suspended wheel with synchronous noise

A disturbance-observer based method is proposed to attenuate the synchronous vibration of a magnetically suspended wheel (MSW). When the rotary speed is nonzero, the synchronous vibration exists. To analyze this vibration, a precise dynamic of the MSW is researched and the synchronous vibrations model is established. A novel vibration attenuation method is proposed by combining a disturbance observer and a state-feedback method. Using Lyapunov's stability theorem, parameters of the controller are determined. Finally, results of numerical simulations and experiments indicate that the proposed method dramatically reduces the synchronous jitter and thus significantly improves precision of the deflection angle.