Conference article

An XML representation of DAE systems obtained from continuous-time Modelica models

Roberto Parrotto
Master’s student - Politecnico di Milano, Italy

Johan Åkesson
Department of Automatic Control, Lund University and Modelon AB, Sweden \ Modelon AB, Lund, Sweden

Francesco Casella
Dipartimento di Elettronica e Informazione, Politecnico di Milano, Italy

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Published in: 3rd International Workshop on Equation-Based Object-Oriented Modeling Languages and Tools; Oslo; Norway; October 3

Linköping Electronic Conference Proceedings 47:10, p. 91-98

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Published: 2010-09-21

ISBN: 978-91-7519-824-8

ISSN: 1650-3686 (print), 1650-3740 (online)


This contribution outlines an XML format for representation of differential-algebraic equations (DAE) models obtained from continuous time Modelica models and possibly also from other equation-based modeling languages. The purpose is to offer a standardized model exchange format which is based on the DAE formalism and which is neutral with respect to model usage. Many usages of models go beyond what can be obtained from an execution interface offering evaluation of the model equations for simulation purposes. Several such usages arise in the area of control engineering; where dynamic optimization; Linear Fractional Transformations (LFTs); derivation of robotic controllers; model order reduction; and real time code generation are some examples. The choice of XML is motivated by its de facto standard status and the availability of free and efficient tools. Also; the XSLT language enables a convenient specification of the transformation of the XML model representation into other formats.


DAE representation; XML design


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