H∞ Controller Design for Magnetically Levitated Steel Plate Conveyance System: Experimental Verification

In this paper, an H-infinity controller is designed for disturbance attenuation of magnetically levitated steel plate. The system contains U-type hybrid electromagnet which constructed by using permanent magnet. A detailed model having nonlinear attraction force of a U-shaped hybrid electromagnet is presented and linearized for controller design purpose. Based on the linearized model, the H-infinity controller is designed to minimize air gap variation under unknown loading disturbances. Thereafter, a set of experiments conducted to compare performance of the H-infinity controller with our previously published I-PD controller on the same experimental setup.