Robust stabilization of a magnetic levitation system

The method of robust stabilization based on H/sup infinity / control is applied to the control of a simple magnetic levitation system on the laboratory scale. The system is highly nonlinear due to the magnetic force which is inversely proportional to the gap width. Also, it contains significant uncertainty of the coil characteristics caused by the temperature variation. To take into account the robustness against the error in linearizing the magnetic force and various kinds of uncertainty due to temperature variation, a robust stabilization method, which has been successfully applied to the control of a flexible beam, is used to design a robust control. The effectiveness of the method was demonstrated in experiments.<<ETX>>