# IPACS Electronic library

## Sensorless Generalized $\mathcal{H}_{\infty}$ Optimal Control of a Magnetic Suspension System

Mark Kogan, Dmitry Balandin, Ruslan Biryukov
An optimal stabilization problem of a body in the electromagnetic suspension is studied. For the linearized system we synthesize the time-invariant output-feedback controller based on the measurement of the current in the solenoid circuit without measuring the position and velocity of the body. A generalized $mathcal{H}_infty$-norm of the linearized system is used as the optimality criterion. It characterizes the disturbance attenuation level for both exogenous signals and an uncertain initial state. The controller parameters are computed using linear matrix inequalities (LMIs). Numerical simulation carried out for the nonlinear mathematical model of the magnetic suspension system demonstrates some advantages of the generalized $mathcal{H}_infty$ controller over standard ones.