State feedback decoupling control of AC 5 degrees of freedom hybrid magnetic bearings

The AC 5 degrees of freedom (DOF) hybrid magnetic bearings (HMB) system is a multivariable, nonlinear and strong coupled system, which requires decoupling control to achieve stable operation at a high speed. In this paper, a dynamic decoupling control approach based on state feedback method is developed for the AC-5DOF-HMB system. Firstly, the configuration of the system and the mathematical models of radial and axial suspension forces are introduced and deduced, respectively. Secondly, based on the setting of the state equations of the system, the control law of state feedback is educed by introducing the theory of state feedback decoupling control. Finally, the control system is designed and simulated. The simulation results show that this kind of control strategy can realize dynamic decoupling control among the 5 displacement subsystems for the AC-5DOF-HMB system, and the whole system has good dynamic and static performance.