An Adaptive-controlled Self-gap-detecting Electromagnetic Suspension System

There are few self-gap-detecting electromagnetic suspension (EMS) systems robust enough against variation of coil resistance. The authors succeeded in providing much robustness against the variation of coil resistance with a self-gap-detecting EMS system. An adaptive control for coil resistance and an exciting voltage compensator for differences between the coil resistances were applied to the self-gap-detecting EMS system. This paper proposes this new self-gap-detecting technique. The adaptive controller and the exciting voltage compensator is explained. The experimental result shows that the proposed controller can keep stability of the EMS system from variations of not only coil resistance but also levitation mass