Article | Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany | Collocation Methods for Optimization in a Modelica Environment

Title:
Collocation Methods for Optimization in a Modelica Environment
Author:
Fredrik Magnusson: Department of Automatic Control, Lund University/Modelon AB, Lund, Sweden Johan Åkesson: Department of Automatic Control, Lund University, Sweden
DOI:
10.3384/ecp12076649
Download:
Full text (pdf)
Year:
2012
Conference:
Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany
Issue:
076
Article no.:
066
Pages:
649-658
No. of pages:
10
Publication type:
Abstract and Fulltext
Published:
2012-11-19
ISBN:
978-91-7519-826-2
Series:
Linköping Electronic Conference Proceedings
ISSN (print):
1650-3686
ISSN (online):
1650-3740
Publisher:
Linköping University Electronic Press; Linköpings universitet


The solution of generic dynamic optimization problems described by Modelica; and its extension Optimica; code using direct collocation methods is discussed. We start by providing a description of dynamic optimization problems in general and how to solve them by means of direct collocation. Next; an existing implementation of a collocation algorithm in JModelica.org; using CasADi and IPOPT; is presented. The extensions made to this implementation are reported. The new implementation is compared to an old C-based collocation algorithm in JModelica.org in two benchmarks. The presented benchmarks are based on a continuously stirred tank reactor and a combined cycle power plant. The new algorithm and its surrounding framework is more flexible and shown to be several times more efficient than its predecessor.

Keywords: dynamic optimization; JModelica.org; collocation; nonlinear programming; CasADi

Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany

Author:
Fredrik Magnusson, Johan Åkesson
Title:
Collocation Methods for Optimization in a Modelica Environment
DOI:
10.3384/ecp12076649
References:
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[11] R. Parrotto; J. Åkesson; and F. Casella; “An XML representation of DAE systems obtained from continuous-time Modelica models;” in 3rd International Workshop on Equation-Based Object-Oriented Modeling Languages and Tools; (Oslo; Norway); pp. 91–98; Oct. 3 2010.
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Proceedings of the 9th International MODELICA Conference; September 3-5; 2012; Munich; Germany

Author:
Fredrik Magnusson, Johan Åkesson
Title:
Collocation Methods for Optimization in a Modelica Environment
DOI:
10.3384/ecp12076649
Note: the following are taken directly from CrossRef
Citations:
  • Roel De Coninck, Fredrik Magnusson, Johan Ă…kesso & Lieve Helsen (2016). Toolbox for development and validation of grey-box building models for forecasting and control. Journal of Building Performance Simulation, 9(3): 288. DOI: 10.1080/19401493.2015.1046933
  • A. Holmqvist, F. Magnusso & S. Stenström (2014). Scale-up analysis of continuous cross-flow atomic layer deposition reactor designs. Chemical Engineering Science, 117: 301. DOI: 10.1016/j.ces.2014.07.002
  • A. Holmqvist, T. Törndahl, F. Magnusson, U. Zimmerman & S. Stenström (2014). Dynamic parameter estimation of atomic layer deposition kinetics applied to in situ quartz crystal microbalance diagnostics. Chemical Engineering Science, 111: 15. DOI: 10.1016/j.ces.2014.02.005
  • Roel De Coninc & Lieve Helsen (2016). Quantification of flexibility in buildings by cost curves – Methodology and application. Applied Energy, 162: 653. DOI: 10.1016/j.apenergy.2015.10.114