In this paper are discussed model order reduction and simplification techniques (e.g.; metrics used by these techniques for rankings of elements) which are applicable to wide range of Modelica models built from already available libraries. Modelica models are translated to set of differential-algebraic equations and for the latter there are numerous tools for model order reduction already available. However; these tools are not designed for helping users understand the model’s behavior and the reduced model may be hard to understand by the user because the structure of the original model is lost. Hierarchical decomposition of the model must be presereved and if the model is developed with a graphical schematics then elements (nodes) of the schematics must be ranked. Therefore we adapted energy-based metrics used in ranking of bond-graphs’ elements to much more losely defined Modelica’s schematics; so they can be used complementary with ranking methods that work with equations.
Keywords: model order reduction; model simplification; verification
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