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

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 mechanicthermodynamic 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.