15th Triennial World Congress of the International Federation of Automatic Control
  Barcelona, 21–26 July 2002 
ROBUST CONTROL SYNTHESIS VIA A GENETIC ALGORITHM AND LMIS
R. H. C. Takahashi* D. C. W. Ramos*** P. L. D. Peres**
* Department of Mathematics, Universidade Federal de Minas Gerais,
Av. Antônio Carlos 6627 - 31270-010, Belo Horizonte - MG - Brazil,
e-mail: taka@mat.ufmg.br
** School of Electrical and Computer Engineering, University of
Campinas, CP 6101, 13081-970, Campinas - SP - Brazil,
e-mail: peres@dt.fee.unicamp.br
*** EMBRAER, São José dos Campos - SP - Brazil,
e-mail: domingos.ramos@embraer.com.br

This paper is concerned with the use of genetic algorithms for robust control synthesis, in a context where there is no convex formulation for such design. For that aim, a robustness analysis condition is given in terms of a linear matrix inequality feasibility problem, producing less conservative results than recent parameter dependent Lyapunov based methods (which encompasses quadratic stability) for polytopic uncertainties in linear systems. Since the design criterion is a closed-loop test formulated in the controller parameter space, any control structure constraint is allowed, such as: low-order dynamic controllers, static output feedback controllers, decentralized control, etc. The role of genetic algorithms for the design of “less conservative” and “structure-constrained” controllers is discussed.
Keywords: Genetic Algorithm, Linear Matrix Inequalities, Parameter Dependent Lyapunov Functions, Robust Control
Session slot T-Th-M16: Evolutionary Algorithms in Control Design/Area code 2a : Control Design