The Bond Graph - an excellent modelling tool to study abstraction level and structure comparison

In this paper the Bond Graph (BG) technique is used for modelling dynamical systems. Thus a typical modern power flow oriented representation ensures energy domain independency, a view inside the studied system and preservation of the physical structure based on special bidirectional connections. A comparison of scalar and vectorial connections between the components and a more detailed classification for vectorial models are firstly given. Thereafter it will be shown that the BG may be used as an excellent tool both for defining different abstraction levels of the same modelling artefact still without using the principle of subsystems and for the detection of the same power flow structure hidden behind different hardware solutions for one given problem. That way the paper proves that scalar, vectorial or compact modelling provides specific advantages respectively and that the definition of two conjugated power variables is a basic principle of structure comparisons. The electrical machine and the task of power split are used as examples close to the subject of vehicle power and propulsion.