Multidomain Systems Modeling With SPICE: Equivalent Circuit and Bond Graph Approaches

Equivalent circuits (EC) and bond graphs (BG) are inventive approaches to represent energy interactions in complex multidomain systems. Undergraduate and graduate students in engineering and physics courses benefit from such intuitive representations as alternatives to abstract space-state models and block diagram forms. However, differences between EC and physical counterparts frustrate their implementation and simulation in network analysis software like the widespread SPICE-based ones. Therefore, this paper proposes a method for converting EC and BG into realizable models through modulated effort/flux sources supported by systematic node labeling. Comparative transient simulations in LTspice and MATLAB encompass examples of mechanical, electrical, and magnetic systems, yielding compatible results apart from the multidomain interfaces. The presented technique supports elaborated models’ development and validation through an open-source and lightweight software, motivating further applications in didactic projects and virtual labs.