Modeling with Respect to Uncertainties for a Magnetic Suspension System of a Double Flexible Beam

Abstract

This paper describes a modeling with unmodeled uncertainties and control configuration for a magnetic suspension system of a double flexible beam. It simplifies both an elastic rotor and a body in a magnetic bearing system. At first, the magnetic suspension system is introduced. Next, dynamical equations of two beam motions as a concentrated state system and an electrical equation of an electromagnet are derived. Then its linearized model with disturbance terms as unmodeled uncertainties is formulated in a state space form. Finally, in order to deal with the uncertainties as a control problem, a standard H^∞ control framework is set up. There the generalized plant is constructed from LQ differential game theoretical point of view, which involves weighting matrices for state variables and control input and frequency weighting functions for uncertainty models.