Passivity approach for controller design and stability analysis of radial power systems

A passivity approach as a framework to analyse stability of power systems and to derive controllers is presented. A radial power system is decomposed according to the component oriented modelling technique which allows to view the whole system as a feedback decomposition suitable to apply the passivity approach. Under assumptions of passive or passified loads, L₂-stability properties are proved along this scheme when disturbances occur in the network. Once disturbances are cleared, asymptotic stability property is derived. In case of non-passivity of certain loads in the network satisfying an energy-like constraint, ultimate boundedness properties are obtained with the quasi-passivity concept