Active Magnetic Bearings Robust Control Design based on Symmetry Properties

This paper describes an H_infin robust control design for an electromechanical system consisting of a rotary flexible spindle hovered by active magnetic bearings (AMB), whose potential uses in the machine-tool industry have been well documented. Symmetry properties are utilized to perform a model reduction avoiding the ill-conditioning of the matrices when H_infin algorithms are solved and hence, facilitating the design of the controller. The better behavior of the system is probed by simulation in a complete model of a real device.