Input disturbance suppression for Port-Controlled Hamiltonian systems via the internal model method

This paper investigates the input disturbance suppression problem for nonlinear Port-Controlled Hamiltonian (PCH) systems and presents a number of new results on the controllers design via the internal model approach. Different from the existing results on this topic we consider two cases: the case of the disturbance generated from a linear Hamiltonian system acts through a channel other than the input channel and the case of the disturbance generated from a bounded nonlinear exosystem is studied by presenting a procedure of designing a nonlinear internal model to zero the effect of the disturbance under two fundamental assumptions. Simulations of a three-order synchronous generator model with disturbance generated from a nonlinear exosystem show the effectiveness of the designed internal model.