Decentralized PI/PD position control for active magnetic bearings

This paper discusses a closed-loop decentralized control for active magnetic bearings. A cascade connection of PI and PD position controllers is proposed. The control design is based on a simplified linearized model for one axis using a root locus. An excellent agreement is noticeable between simulation and experimental results. It has been shown, that the presented PI/PD control guarantees satisfactory high damping and stiffness of the overall system.