ロバスト最小次元VSSオブザーバを適用した弾性ロータ・磁気軸受系のスライディングモード制御

抄録

This paper deals with the flexible rotor-mangetic bearing system (FR-MBS) which has three concentrated masses. A mathematical model of the flexible rotor in the case of free-free condition is derived using a finite-element method. The reduced-order model is derived for control system design by eliminating higher-order modes. Three kinds of reduced-order observers have been designed in this paper. We have confirmed that the VSS reduced-order observers have greater robustness to parameter variations in the system. The sliding mode controller for this reduced-order model is proposed using sliding mode control theory, and the simulations are done on the calculating model in the two cases of the lift-off and rotations. The two unstable rigid modes can be easily controlled with good stability and the spillover phenomena caused by the higher-order modes do not occur. Moreover it is clear that the sliding mode control design is robust with respect to model parameter variations and external disturbances.