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Robust Adaptive Observer Design for a Class of Nonlinear Systems via an Optimization Method

최적화 기법에 의한 비선형 시스템에서의 강인한 적응 관측기 설계

  • 정종철 (한양대학교 대학원 자동차공학과) ;
  • 허건수 (한양대학교 기계공학부)
  • Published : 2006.10.01

Abstract

Existing adaptive observers may cause the parameter drifts due to disturbances even if state estimation errors remain small. To avoid the drift phenomena in the presence of bounded disturbances, several robust adaptive observers have been introduced addressing bounds in state and parameter estimates. However, it is not easy for these observers to manipulate the size of the bounds with the selection of the observer gain. In order to reduce estimation errors, this paper introduces the (equation omitted) gain minimization problem in the adaptive observer structure, which minimizes the (equation omitted) gain between disturbances and estimation errors. The stability condition of the adaptive observer is reformulated as a linear matrix inequality, and the observer gain is optimally chosen by solving the convex optimization problem. The estimation performance is demonstrated through a numerical example.

Keywords

Adaptive Observer;Robustness;LMI(Linear Matrix Inequality);Optimization Problem

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