# Polytopic Quasi-LPV 모델 기반 능동자기베어링의 비선형제어기 설계

• 이동환 (연세대학교 전기전자공학과) ;
• 박진배 (연세대학교 전기전자공학과) ;
• 정현석 (군산대학교 전자정보공학부) ;
• 주영훈 (군산대학교 제어로봇시스템공학과)
• Accepted : 2010.01.30
• Published : 2010.04.01
• 36 12

#### Abstract

In this paper, a systematic procedure to design a nonlinear controller for nonlinear active magnetic bearing (AMB) systems is presented. To do this, we effectively convert the AMB system into a polytopic quasi-linear parameter varying (LPV) system, which is a representation of nonlinear state-space models and is described by the convex combination of a set of precisely known vertices. Unlike the existing quasi-LPV systems, the nonlinear weighting functions, which construct the polytopic quasi-LPV model of the AMB system by connecting the vertices, include not only state variables but also the input ones. This allows us to treat the input nonlinearity effectively. By means of the derived polytopic quasi-LPV model and linear matrix inequality (LMI) conditions, nonlinear controller that stabilizes the AMB system is obtained. The effectiveness of the proposed controller design methodology is finally demonstrated through numerical simulations.

#### Keywords

Active Magnetic Bearing (AMB);Polytopic Quasi-Linear Papameter Varying (LPV) Systems;Linear Matrix Inequality (LMI);Stabilization;Nonlinear Systems

#### Acknowledgement

Supported by : 한국연구재단

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