Interconnection and Damping Assignment - Passivity Based Control of Irreversible Port Hamiltonian Systems

Abstract

Irreversible port Hamiltonian systems are a class of pseudo Hamiltonian systems that expresses both the conservation of energy and the irreversible entropy production as a structural property. These systems encompass a large class of irreversible themordynamic systems, such as heat exchangers and chemical reactors, and also multi-energy systems such as coupled mechanic-thermodynamic systems. In recent work the irreversible port-Hamiltonian formulation has been used to derive a closed-loop stability condition using an energy based availability function, generated by the internal energy, as Lyapunov function. This paper presents an important extension of the previous results: the system theoretic interpretation of the stability condition in terms of conjugated inputs and outputs and the formulation of the control as an interconnection and damping assignment - passivity based control problem. A constructive method to derive the stabilizing control law is proposed and the formalism is illustrated on a general CSTR example.