Clarifying Energy Storage Field Structure in Dynamic Systems

The energy variables associated with a dynamic system can be considered as a set of candidate state variables. However, when algebraic coupling among the energy variables exists, then the associated state-space equations are implicit in form. Typically, such equations require implicit integration methods for their solution, unless the original model is modified suitably. Bond graph models, through the use of causality techniques, allow one to identify the existence of algebraic energy-variable coupling. Based on the detailed nature of the coupling, various options are available for solving such problems. In this paper a modification of and extension to the standard Sequential Causality Assignment Procedure is given that permits the detailed identification of the structure of energy fields.