Application of gain scheduled H_∞ robust controllers to a magnetic bearing

This paper deals with the problem of an unbalance vibration zof the magnetic bearing system. We design a control system achieving the elimination of the unbalance vibration, using a loop shaping design procedure (LSDP). After the introduction of our experimental setup, a mathematical model of the magnetic bearing is shown. Then, the gain scheduled H_∞ robust controllers with free parameters are designed, based on the LSDP, so as to asymptotically reject the disturbances caused by unbalance on the rotor, even if the rotational speed of the rotor varies. Finally, several simulation results and experimental results show the effectiveness of this proposed methodology.