Variable selection for decentralized controlAuthors: Sigurd Skogestad and Manfred MorariAffiliation: NTNU and California Institute of Technology Reference: 1992, Vol. 13, No. 2, pp. 113-125. |
Keywords: DIC, relative gain array (RGA), steady-state, integral control, interactions
Abstract: Decentralized controllers (single-loop controllers applied to multivariable plants) are often preferred in practice because they are robust and relatively simple to understand and to change. The design of such a control system starts with pairing inputs (manipulated variables) and outputs (controlled variables). For a nxn plant there are n! possible pairings, and there is a great need for screening techniques to quickly eliminate undesirable pairings. In this paper we present several tests for eliminating pairings which are not decentralized integral controllable (DIC). A system is DIC if there exists a stabilizing decentralized controller with integral action such that the gains of the individual loops may be reduced independently without introducing instability. Note that the DIC is a property of the plant and the chosen pairings. The tests presented are in terms of different measures of the sign of the steady state gain matrix; including the RGA, the determinant and eigenvalues. The relationship to previously presented results is discussed in detail.
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DOI: 10.4173/mic.1992.2.3
DOI forward links to this article:
[1] Miltiadis V. Papalexandris, (2004), doi:10.1115/1.1789537
[2] Nima Monshizadeh-Naini Alireza Fatehi Ali Kahki-Sedigh, (2011), doi:10.1016/j.automatica.2010.10.008
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BibTeX:
@article{MIC-1992-2-3,
title={{Variable selection for decentralized control}},
author={Skogestad, Sigurd and Morari, Manfred},
journal={Modeling, Identification and Control},
volume={13},
number={2},
pages={113--125},
year={1992},
doi={10.4173/mic.1992.2.3},
publisher={Norwegian Society of Automatic Control}
};


