An LMI Approach to Mixed H2/H8 Synthesis via Dynamic Output-Feedback for Active Magnetic Bearing

This paper considers the robust control of an active radial magnetic bearing system, having a homopolar, external rotor topology, which is used to support an annular fiber composite flywheel rim. A second-order dynamical compensator is used for control, its design being based on a linearized one-dimensional model which is treated as an interval system in order to cope with parameter uncertainties. We formulate a problem of multiobjective dynamic output feedback synthesis which incorporate nominal H₂ and H_infin performances. Simulation results demonstrate both stability and performance robustness of the developed controller.