Article | Proceedings of the 2nd International Workshop on Equation-Based Object-Oriented Languages and Tools | Selection of Variables in Initialization of Modelica Models

Title:
Selection of Variables in Initialization of Modelica Models
Author:
Masoud Najafi: INRIA-Rocquencourt, Domaine de Voluceau, France
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Full text (pdf)
Year:
2008
Conference:
Proceedings of the 2nd International Workshop on Equation-Based Object-Oriented Languages and Tools
Issue:
029
Article no.:
012
Pages:
111-119
No. of pages:
9
Publication type:
Abstract and Fulltext
Published:
2008-07-02
ISBN:
978-91-7519-823-1
Series:
Linköping Electronic Conference Proceedings
ISSN (print):
1650-3686
ISSN (online):
1650-3740
Publisher:
Linköping University Electronic Press; Linköpings universitet


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In Scicos; a graphical user interface (GUI) has been developed for the initialization of Modelica models. The GUI allows the user to fix/relax variables and parameters of the model as well as change their initial/guess values. The output of the initialization GUI is a pure algebraic system of equations which is solved by a numerical solver. Once the algebraic equations solved; the initial values of the variables are used for the simulation of the Modelica model. When the number of variables of the model is relatively small; the user can identify the variables that can be fixed and can provide the guess values of the variables. But; this task is not straightforward as the number of variables increases. In this paper; we present the way the incidence matrix associated with the equations of the system can be exploited to help the user to select variables to be fixed and to set guess values of the variables during the initialization phase.

Keywords: Modelica; initialization; coupling algorithm; numerical solver; Scicos

Proceedings of the 2nd International Workshop on Equation-Based Object-Oriented Languages and Tools

Author:
Masoud Najafi
Title:
Selection of Variables in Initialization of Modelica Models
References:

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Proceedings of the 2nd International Workshop on Equation-Based Object-Oriented Languages and Tools

Author:
Masoud Najafi
Title:
Selection of Variables in Initialization of Modelica Models
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