Passivity-based output synchronisation of port-controlled Hamiltonian and general linear interconnected systems

Abstract

This article studies output synchronisation of a set of non-linear interconnected systems and general linear interconnected systems. It will be shown that output synchronisation of the systems can be achieved by adding a new coupling interconnections (consensus algorithm) to the existing interconnections if the input and output relationship of the given system is passive. The output synchronisation scheme will then be applied to a class of interconnected non-linear systems with the special structure of port-controlled Hamiltonian (PCH) dynamics. Since the structure of the PCH systems is restrictive, we further present a synthesis of state feedback controller to overcome the restriction. This result will be applied to multi-machine power systems. As the second part of this paper, the output synchronisation of general linear interconnected systems will be ensured. In the case of linear interconnected systems, the synchronisation can be achieved by a decentralised observer-based output feedback control scheme. The controller and observer gains will be calculated from decentralised linear matrix inequality conditions. Simulation tests are conducted to evaluate the performance of the proposed methods.