Instabilities in Adaptive Control Systems

  • Romeo Ortega
  • Tang Yu
Conference paper
Part of the Lecture Notes in Control and Information Sciences book series (LNCIS, volume 83)


An exposition of some of the results in continuous-time adaptive control systems in stability is given. We study instabilities that arise due to: high adaptation gain and/or large reference signals, interplay between unmodeled dynamics and output dis turbances and crosscoupling in decentralized controllers. In all cases simple worked examples are included to illustrate the phenomena. In the disturbance-free case, the causes of instability are rigorously explained via instability theorems. The basic purpose of the paper is to establish criteria for instability, however, conditions for stability are also formulated concurrently.


Adaptive Control Adaptive System Adaptive Controller Unmodeled Dynamic Adaptive Control System 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media Dordrecht 1986

Authors and Affiliations

  • Romeo Ortega
    • 1
  • Tang Yu
    • 1
  1. 1.Facultad de Ingeniería ApdoDivisión de Estudios de PosgradoMéxico, D.F.Mexico

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