Abstract
It is well known that the Smith Predictor Controller SPC may be very sensitive to model-plant mismatch, resulting in a poor performance when model uncertainty is present. This paper introduces two criteria for the design of a SPC when the plant-rational part and time delay- is not precisely known.
The first criterion (First Step) is based on bandwidth frequency considerations. The procedure finds the set of models of the plant so that, if the SPC adopts one of them, the desired bandwidth BW will not be reduced by the effect of the parameter uncertainty.
The second criterion (Second Step) introduces some guidelines to improve the design of the SPC by using the QFT technique. That lead us to make the question that which is the optimal model of the plant that we have to choose in order to improve the resulting templates, i.e. to make easier the loop-shaping, and hence to present the less restrictive system to the controller design stage.
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References
Smith, O.J.M., 1957. Closer control of loops with dead time. Chem. Eng. Progr., 53, 217–219.
Ioannides, A.C., G.J. Rogers and V. Latham, 1979. Stability limits of a Smith controller in simple systems containing a dead-time. Int.J.Control, 29, 557–563.
Palmor, Z., 1980. Stability properties of Smith dead-time compensator controllers. Int. J. Control, 32, 937–949.
Horowitz, I., 1983. Some properties of delayed controls (Smith regulator). Int.J.Control, 38, 977–990.
Yamanaka, K. and E. Shimemura, 1987. Effects of mismatched Smith controller on stability in systems with time-delay. Automatica, 23, 787–791.
Horowitz, I., 1991. Survey of quantitative feedback theory. Int. J. Control, 53 (2), 255–291.
D'Azzo, J. J. and C. H. Houpis, 1995. Quantitative Feedback Theory (QFT) Technique. In: Linear Control System Analysis and Design. 4th Ed. (McGraw Hill, New York), 580–635.
Astrom, K.J., 1977. Frequency domain properties of Otto Smith regulators. Int.J.Control, 26, 307–314.
Marlin, T.E., 1995. Process Control. (McGraw-Hill, Inc.), 620–634.
Santacesaria, C. and R. Scattolini, 1993. Easy tuning of Smith Predictor in Presence of Delay Uncertainty, Automatica, 29 (6), 1595–1597.
Borghesani, C., Y. Chait and O. Yaniv, 1995. Quantitative Feedback
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© 1999 Springer-Verlag London Limited
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Garcia-Sanz, M., Guillen, J.G. (1999). Smith predictor for uncertain systems in the QFT framework. In: Tzafestas, S.G., Schmidt, G. (eds) Progress in system and robot analysis and control design. Lecture Notes in Control and Information Sciences, vol 243. Springer, London. https://doi.org/10.1007/BFb0110548
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DOI: https://doi.org/10.1007/BFb0110548
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