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Dynamic start-up optimization of a plate reactor with uncertainties

Haugwitz, Staffan LU ; Åkesson, Johan LU and Hagander, Per LU (2009) In Journal of Process Control 19(4). p.686-700
Abstract
In this paper, start-up of a plate reactor with an exothermic reaction is considered. Dynamic optimization is used to obtain start-up trajectories, while a feedback control system is designed for on-line control. The problem is challenging, since the process model is highly nonlinear, and subject to uncertainty. Limited bandwidth of the feedback control system requires that the optimization gives optimal solutions with low sensitivity to uncertainty. Special attention is given to the problem of formulating an optimal control problem based on physical insight to reduce the sensitivity of the solution, thus increasing the overall robustness of the closed loop system. The resulting solutions are evaluated in Monte Carlo simulations. The study... (More)
In this paper, start-up of a plate reactor with an exothermic reaction is considered. Dynamic optimization is used to obtain start-up trajectories, while a feedback control system is designed for on-line control. The problem is challenging, since the process model is highly nonlinear, and subject to uncertainty. Limited bandwidth of the feedback control system requires that the optimization gives optimal solutions with low sensitivity to uncertainty. Special attention is given to the problem of formulating an optimal control problem based on physical insight to reduce the sensitivity of the solution, thus increasing the overall robustness of the closed loop system. The resulting solutions are evaluated in Monte Carlo simulations. The study shows that introducing concentration constraints on the injected chemical in combination with high frequency penalties on the control signals lead to less sensitive optimal solutions, thus yielding a more robust start-up. Automatic computer tools that greatly simplifies the task of formulating complex dynamic optimization problems have been used to obtain the start-up trajectories and are briefly presented. (C) 2008 Elsevier Ltd. All rights reserved (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Process control, Uncertainty, Dynamic optimization, Sensitivity, Plate, reactor, Modelica
in
Journal of Process Control
volume
19
issue
4
pages
686 - 700
publisher
Elsevier
external identifiers
  • wos:000265992100013
  • scopus:63249090547
ISSN
1873-2771
DOI
10.1016/j.jprocont.2008.07.005
language
English
LU publication?
yes
id
2ad8e2db-ea33-4e68-8994-c5ca1baa8531 (old id 1425915)
date added to LUP
2009-06-26 14:31:30
date last changed
2017-08-27 04:09:15
@article{2ad8e2db-ea33-4e68-8994-c5ca1baa8531,
  abstract     = {In this paper, start-up of a plate reactor with an exothermic reaction is considered. Dynamic optimization is used to obtain start-up trajectories, while a feedback control system is designed for on-line control. The problem is challenging, since the process model is highly nonlinear, and subject to uncertainty. Limited bandwidth of the feedback control system requires that the optimization gives optimal solutions with low sensitivity to uncertainty. Special attention is given to the problem of formulating an optimal control problem based on physical insight to reduce the sensitivity of the solution, thus increasing the overall robustness of the closed loop system. The resulting solutions are evaluated in Monte Carlo simulations. The study shows that introducing concentration constraints on the injected chemical in combination with high frequency penalties on the control signals lead to less sensitive optimal solutions, thus yielding a more robust start-up. Automatic computer tools that greatly simplifies the task of formulating complex dynamic optimization problems have been used to obtain the start-up trajectories and are briefly presented. (C) 2008 Elsevier Ltd. All rights reserved},
  author       = {Haugwitz, Staffan and Åkesson, Johan and Hagander, Per},
  issn         = {1873-2771},
  keyword      = {Process control,Uncertainty,Dynamic optimization,Sensitivity,Plate,reactor,Modelica},
  language     = {eng},
  number       = {4},
  pages        = {686--700},
  publisher    = {Elsevier},
  series       = {Journal of Process Control},
  title        = {Dynamic start-up optimization of a plate reactor with uncertainties},
  url          = {http://dx.doi.org/10.1016/j.jprocont.2008.07.005},
  volume       = {19},
  year         = {2009},
}