Abstract
This paper deals with modeling, uncertain structure and μ-synthesis of a magnetic suspension system. The dynamics of magnetic suspension systems are characterized by their instability and complexity of electro-magnets, and they should be robustly stabilized in spite of model uncertainties. First we derive a nominal design model of the plant under some assumption, then we investigate the gap between the real physical system and the obtained nominal design model. This gap has complex structure which is expressed by the structured uncertainties that includes linearization error, parametric uncertainties, and neglected dynamics. Then we set the interconnection structure which contains the above structurally represented uncertainties. Next we design a robust controller which achieves robust performance using the structured singular value μ. Finally, we evaluate the proposed interconnection structure and verify robustness and performance of the designed μ controller by several experiments.
