Elimination in control theory

  • Sette Diop


For nonlinear systems described by algebraic differential equations (in terms of “state” or “latent” variables) we examine the converse to realization,elimination, which consists of deriving an externally equivalent representation not containing the state variables. The elimination in general yields not only differential equations but also differentialinequations. We show that the application of differential algebraic elimination theory (which goes back to J.F. Ritt and A. Seidenberg) leads to aneffective method for deriving the equivalent representation. Examples calculated by a computer algebra program are shown.

Key words

Equivalent system representations Latent variable elimination State elimination Elimination theory Differential polynomial algebras 


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Copyright information

© Springer-Verlag New York Inc. 1991

Authors and Affiliations

  • Sette Diop
    • 1
  1. 1.Laboratoire d’Automatique et de Génie des Procédés, URA D 1328 du CNRSUniversité Claude Bernard Lyon 1Villeurbanne cedexFrance

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