Nonlinear controller design of active magnetic bearing systems based on polytopic quasi-LPV models

Dong Hwan Lee, Jin Bae Park, Hyun Suk Jeong, Young Hoon Joo

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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.

Original languageEnglish
Pages (from-to)797-802
Number of pages6
JournalTransactions of the Korean Institute of Electrical Engineers
Issue number4
Publication statusPublished - 2010 Apr 1


All Science Journal Classification (ASJC) codes

  • Electrical and Electronic Engineering

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