A class of port-controlled Hamiltonian systems

In this paper, we examine a particular class of port-controlled Hamiltonian systems for which the equations can be written in a form that is very similar to the equations of a linear passive system. We examine the passivity of such a system around an equilibrium point (u0,x0), which generates the output y0. We show that under some mild assumptions, a new Hamiltonian can be found such that the system is again passive with respect to the new supply rate (y-y0)^T(u-u0).