Conference article

Modelica provides intuitive constructs to create and group model definitions. However; models themselves do not compose. In other words; the connection of type-compatible and locally balanced submodels does not generally yield a valid (e.g.; balanced; structurally non-singular) model. Starting from simple examples of such invalid models (resulting from commonly encountered situations when using Modelica); this paper explains how those problems could be avoided by introducing a safer notion of physical connector; similar in some aspects to the VHDL-AMS notion of terminal. An extension of the notion of connection is also presented; providing new opportunities to make efficient use of ideal models in Modelica.

Model composition; high-level physical connector; effort variable; flow variable; connection graph; effort graph; flow graph