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“Coordinator MPC for maximizing plant throughput”

Authors: Elvira M.B. Aske, Stig Strand and Sigurd Skogestad,
Affiliation: NTNU, Department of Chemical Engineering and Statoil
Reference: 2008, Vol 29, No 3, pp. 103-115.

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Keywords: bottleneck, maximize throughput, MPC

Abstract: In many cases economic optimal operation is the same as maximum plant throughput, which is the same as maximum flow through the bottleneck(s). This insight may greatly simplify implementation. In this paper, we consider the case where the bottlenecks may move, with parallel flows that give rise to multiple bottlenecks and with crossover flows as extra degrees of freedom. With the assumption that the flow through the network is represented by a set of units with linear flow connections, the maximum throughput problem is then a linear programming (LP) problem. We propose to implement maximum throughput by using a coordinator model predictive controller (MPC). Use of MPC to solve the LP has the benefit of allowing for a coordinated dynamic implementation. The constraints for the coordinator MPC are the maximum flows through the individual units. These may change with time and a key idea is that they can be obtained with almost no extra effort using the models in the existing local MPCs. The coordinator MPC has been tested on a dynamic simulator for parts of the Kårstø gas plant and performs well for the simulated challenges.

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DOI forward links to this article:
  [1] L.F. Acebes, A. Merino, A. Rodriguez, R. Mazaeda and C. de Prada (2019), doi:10.1016/j.jprocont.2019.05.005


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BibTeX:
@article{MIC-2008-3-3,
  title={{Coordinator MPC for maximizing plant throughput}},
  author={Aske, Elvira M.B. and Strand, Stig and Skogestad, Sigurd},
  journal={Modeling, Identification and Control},
  volume={29},
  number={3},
  pages={103--115},
  year={2008},
  doi={10.4173/mic.2008.3.3},
  publisher={Norwegian Society of Automatic Control}
};

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