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Vol: 51(65) No: 3 / September 2006 Adaptive Self-Tuning Controllers Design based on Minimum Variance Strategies Ioan Filip Dept. of Automation and Applied Informatics, “Politehnica” University Timisoara, Bd. V. Parvan 2, 300223 Timisoara, Romania, phone: (+40) 0256-403238, e-mail: ioan.filip@aut.upt.ro, web: http://www.aut.upt.ro/~ifilip/ Keywords: self-tuning control, minimum variance control strategies, parameters estimator, control system stability. Abstract This paper describes two particular cases of the generalized minimum variance control strategy, usable for an adaptive self-tuning controllers design. The first strategy assures a compensation of output error (and a minimized control variance), and the second contains (additionally) a compensation mechanism of the reference value. Both approached control strategies have as result the synthesis of specific control law embedded in a self-tuning controller. A comparative study is performed concerning the stability of both control systems. References [1] K.J. Astrom and B. Wittenmark, \"Adaptive Control\", Addison-Wesley Publishing Company, Massachusetts, 1989. [2] I. Filip, O. Prostean, I. Szeidert, G. Prostean and C. Vasar, \"Self-tuning Control Using External Integrator Loop for a Synchronous Generator Excitation System\", Proc. 11th IEEE International Conference on Emerging Technologies and Factory Automation, ETFA2006, Prague, September 20-22, 2006. [3] D.P. Looze, \"Minimum variance control structure for adaptive optics systems\", Proc. American Control Conference, 2005. [4] V. Bobal, J. Bohm, J. Fessl and J.Machacek, \"Digital Self-tuning Controllers\", Acta Press, 2005. [5] L.M. Miskovicacute, Z.M. Djurovic and B. D. Kovacevicacute, \"Application of the minimum state error variance approach to nonlinear system control\", International Journal of Systems Science, vol. 33, no. 5, April 2002. [6] P.R. Kumar, \"Convergence of Adaptive Control Schemes Using Least-Squares Parameter Estimates², IEEE Transactions on Automatic Control, vol. 35, no. 5, Apr. 1990. [7] A. Loria, R. Kelly and A.R. Teel, \"Uniform parametric convergence in the adaptive control of manipulators: a case restudied\", Proc. IEEE International Conference on Robotics and Automation ICRA’03, 2003. [8] P.E. Wellstead and M.B. Zarrop, \"Self-Tuning Systems - Control and Signal Processing\", John Wiley & Sons Ltd., England, 1991. [9] S. Sastry and M. Bodson, \"Adaptive Control: Stability, Convergence, and Robustness\", Prentice-Hall, 1994. |