Structural analysis and duality for bond graph models

The object of this paper is to shown how the algebraic approach plays an essential role in order to extend classical graphical procedures developed on linear time invariant bond graph models for the study of solvability conditions of classical problems such as disturbance rejection, input-output decoupling, unknown input observers and fault detection and isolation problems. This extension is addressed to linear time varying bond graph models. Two key points in this paper are the concept of duality and structural analysis.