Conference article

Simulating Modelica models with a Stand-Alone Quantized State Systems Solver

Federico Bergero
CIFASIS-CONICET, Rosario, Argentina

Xenofon Floros
Department of Computer Science, ETH Zurich, Switzerland

Joaquín Fernández
CIFASIS-CONICET, Rosario, Argentina

Ernesto Kofman
CIFASIS-CONICET, Rosario, Argentina

François E. Cellier
Department of Computer Science, ETH Zurich, Switzerland

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

Linköping Electronic Conference Proceedings 76:23, p. 237-246

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Published: 2012-11-19

ISBN: 978-91-7519-826-2

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


This article describes an extension of the OpenModelica Compiler that translates regular Modelica models into a simpler language; called Micro–Modelica (mu–Modelica); that can be understood by the recently developed stand–alone Quantized State Systems (QSS) solvers. These solvers are very efficient when simulating systems with frequent discontinuities. Thus; strongly discontinuous Modelica models can be simulated noticeably faster than with the standard discrete time solvers. The simulation of two discontinuous models is analyzed in order to demonstrate the correctness of the proposed implementation as well as the advantages of using the QSS stand-alone solvers.


OpenModelica; Quantized State Systems; Micro-Modelica; efficient simulation; discontinuous systems


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