15th Triennial World Congress of the International Federation of Automatic Control
  Barcelona, 21–26 July 2002 
CONSERVATIVITY OF ELLIPSOIDAL STABILITY REGIONS ESTIMATES FOR INPUT SATURATED LINEAR SYSTEMS
J.M. Gomes da Silva Jr* S. Tarbouriech** R. Reginatto*
* UFRGS - Department of Electrical Engineering
Av. Osvaldo Aranha 103, 90035-190 Porto Alegre-RS, Brazil.
E-mail: jmgomes@delet.ufrgs.br, romeu@delet.ufrgs.br
** LAAS-CNRS
7 Avenue du Colonel Roche, 31077 Toulouse cedex 4, France.
E-mail: tarbour@laas.fr

This paper presents a comparative study of different existing algorithms for determining stability domains for linear systems with saturating inputs. Algorithms based on the solution of LMI problems carried out on the basis of three different saturation models, namely regions of saturation, differential inclusion, and sector modeling, are analyzed and compared in terms of their ability to provide large stability domains for the closed-loop system. The main reasons such algorithms incorporate conservativity are highlighted, this being the main contribution of this paper. Results are illustrated by means of an example.
Keywords: saturation control, linear systems, stability domains, optimization
Session slot T-We-M08: Stability and Stabilization/Area code 2c : Non-linear Systems