“Input saturation in nonlinear multivariable processes resolved by nonlinear decoupling”

Authors: Jens G. Balchen and Bjarne Sandrib,
Affiliation: NTNU, Department of Engineering Cybernetics
Reference: 1995, Vol 16, No 2, pp. 95-106.

Keywords: Multivariable control, saturation, nonlinear decoupling

Abstract: A new method is presented for the resolution of the problem of input saturation in nonlinear multivariable process control by means of elementary nonlinear decoupling (END). Input saturation can have serious consequences particularly in multivariable control because it may lead to very undesirable system behaviour and quite often system instability. Many authors have searched for systematic techniques for designing multivariable control systems in which saturation may occur in any of the control variables (inputs, manipulated variables). No generally accepted method seems to have been presented so far which gives a solution in closed form. The method of elementary nonlinear decoupling (END) can be applied directly to the case of saturation control variables by deriving as many control strategies as there are combinations of saturating control variables. The method is demonstrated by the multivariable control of a simulated Fluidized Catalytic Cracker (FCC) with very convincing results.

PDF PDF (1153 Kb)        DOI: 10.4173/mic.1995.2.2

DOI forward links to this article:
[1] Michael J. Kurtz and Michael A. Henson (1997), doi:10.1016/S0959-1524(96)00006-6
[2] A.G. Montandon, R.M. Borges and H.M. Henrique (2006), doi:10.3182/20060402-4-BR-2902.00415
References:
[1] BALCHEN, J.G. (1993). Design of the property transformation in elementary nonlinear decoupling of multivariable processes, Modeling, Identification and Control, 14, 219-227 doi:10.4173/mic.1993.4.3
[2] BALCHEN, J.G. SANDRIB, B.J. (1994). Elementary nonlinear decoupling control of composition in binary distillation columns, IFAC Symp. ADCHEM´94, Kyoto, Japan, May 1994.
[3] BALCHEN, J.G., LJUNGQUIST, D. STRAND, S. (1992). State-space predictive control, Chemical Engineering Science, 47, 787-807 doi:10.1016/0009-2509(92)80268-H
[4] BIEGLER, L.T. (1984). Solution of dynamic optimization problems by successive quadratic programming and orthogonal collocation, Comp. Chem. Engn., 5, 243-248 doi:10.1016/0098-1354(84)87012-X
[5] ISIDORI, A. (1989). Nonlinear Control Systems (2nd ed, ) (Springer Verlag, Berlin).
[6] KOTHARE, M.V., CAMPO, P.J., MORARI, M. NETT, C.N. (1993). A unified framework for the study of anti-windup designs, AIChE Annual Meeting. St. Louis, Paper no. 149d.
[7] LJUNGQUIST, D. (1990). On-line estimation in nonlinear state-space models with application to catalytic cracking, Dr. ing Thesis, Department of Engineering Cybernetics, The Norwegian Institute of Technology, Trondheim, Report nx-1990:89W.
[8] SINGSTAD, P. (1992). Modelling and multivariable control of high pressure autoclave reactors for polymerization of ethene, Department of Engineering Cybernetics, The Norwegian Institute of Technology, Trondheim. Report ITK- I992:29-W.


BibTeX:
@article{MIC-1995-2-2,
  title={{Input saturation in nonlinear multivariable processes resolved by nonlinear decoupling}},
  author={Balchen, Jens G. and Sandrib, Bjarne},
  journal={Modeling, Identification and Control},
  volume={16},
  number={2},
  pages={95--106},
  year={1995},
  doi={10.4173/mic.1995.2.2},
  publisher={Norwegian Society of Automatic Control}
};