On Practical Implementations of Adaptive Control

  • C. C. Hang
  • K. W. Lim
  • T. T. Tay


Practical aspects of adaptive control are discussed. Basic assumptions such as linearity, persistent excitation, known process order and dead time could be violated unless special precautions are taken. Implementation guidelines to avoid consequent problems such as estimator windup and parameter divergence are surveyed. Further findings on practical aspects are derived from extensive studies in the implementation of an adaptive Smith Predictor. In particular, the effects of d.c. levels and of faults such as static load disturbance and large parameter change are discussed. A new solution based on a two-level fault detection scheme with modified estimator is introduced and substantiated by simulation.


Fault Detection Adaptive Control Dead Time Adaptive Controller Recursive Little Square 
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.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. [1]
    K.J. Aström, “Theory and Applications of Adaptive Control–a Survey,” Automatica, vol. 19, pp. 471–486, 1983.zbMATHCrossRefGoogle Scholar
  2. [2]
    G.C. Goodwin and K.S. Sin, Adaptive Filtering Prediction and Control, Prentice-Hall, 1984.Google Scholar
  3. [3]
    C.J. Harris and S.A. Billings, “Self-tuning and Adaptive Control: Theory and Applications,” IEEE Publication, 1981.Google Scholar
  4. [4]
    R. Isermann, Digital Control Systems, Springer-Verlag, 1981.Google Scholar
  5. [5]
    A. Hodgson, “Problems of Integrity in Applications of Adaptive Controllers,” Ph.D. thesis, Dept. of Engrg. Sc., Oxford University, UK, 1982.Google Scholar
  6. [6]
    B. Wittenmark and K.J. Aström, “Practical Issues in the Implementation of Self-tuning Control,” Automatica, vol. 20, pp. 595–606, 1984.zbMATHCrossRefGoogle Scholar
  7. [7]
    C.C. Hang, T.H. Lee and T.T. Tay, “Application of Recursive Parameter Estimation as an Auto-tuning Aid,” to be presented at ISA Annual Conference, Oct. 1985.Google Scholar
  8. [8]
    E. Irving, “Improving Power Network Stability and Unit Stress with Adaptive Generator Control,” Automatica, vol. 15, pp. 31–46, 1979.zbMATHCrossRefGoogle Scholar
  9. [9]
    T.R. Fortescue, L.S. Kershenbaum and B.E. Ydstie, “Implementation of Self-tuning Regulators with Variable Forgetting Factors,” Automatica, vol. 17, pp. 831–835, 1981.CrossRefGoogle Scholar
  10. [10]
    P.E. Wellstead and S.P. Sanoff, “Extended Self-tuning Algorithm,” Int. J. Control, vol. 34, pp. 433–455, 1981.CrossRefGoogle Scholar
  11. [11]
    T. Hagglund, “New Estimation Techniques for Adaptive Control,” Ph.D. thesis, Dept. of Automative Control, Lund Institute of Technology, Sweden, 1984.Google Scholar
  12. [12]
    T. Hagglund, “Adaptive Control of Systems Subject to Large Parameters Changes,” Proc. IFAC World Congress, Budapest, July 1984, pp. 202–207.Google Scholar
  13. [13]
    T.H. Lee and C.C. Hang, “The Effects of an Unmeasurable Step Disturbance on Recursive Parameter Estimation and Adaptive Control,” Proc. Int. Workshop on Appl. of Adaptive Systems Theory, Yale University, June 1983, pp. 223–227.Google Scholar
  14. [14]
    T.H. Lee and C.C. Hang, “A Performance Study of Parameter Estimation Schemes for Systems with Unknown Dead Time,” Proc. American Control Conference, Boston, June 1985, pp. 512–516.Google Scholar
  15. [15]
    T.T. Tay, “Computer Control of a Process with Significant Dead Time,” Final Year Project Report, National Univ. of Singapore, March 1985.Google Scholar
  16. [16]
    J.S. Moczek, R.E. Otto and T.J. Williams, “Approximation Models for the Dynamic Response of Large Distillation Columns,” Proc. IFAC World Congress, Switzerland, August 1963, pp. 238–248.Google Scholar
  17. [17]
    K.Y. Leong, C.C. Lim and C.C. Hang, “Auto-tuning of Cost Function Parameters for a Class of Explicit Stochastic Self-tuning Controllers,” Report CI-84–6, National Univ. of Singapore, August 1984.Google Scholar
  18. [18]
    K.J. Aström and J.J. Anton, “Expert Control,” Proc. IFAC World Congress, Budapest, July 1984, pp. 245–250.Google Scholar

Copyright information

© Springer Science+Business Media New York 1986

Authors and Affiliations

  • C. C. Hang
    • 1
  • K. W. Lim
    • 1
  • T. T. Tay
    • 1
  1. 1.Dept. of Electrical EngineeringNational University of SingaporeKent RidgeSingapore

Personalised recommendations