Control design of a cascade boost converter based on the averaged model

Cascade DC-DC power converters have as main advantage the large output-input voltage relation they provide. This advantage makes them ideal in applications such as the conversion of energy generated by means of non conventional sources. The boost converter dynamics is nonlinear and its linearization yields a non-minimum phase system, therefore a controller design must include the injection of damping to assure the asymptotic stability of the closed-loop system. In this paper is presented the design of an output feedback controller for the cascade boost of two stages, which is based on the dynamics of the averaged model of the power converter. The objective of the controller is the regulation of the output voltage to a desired reference, irrespective of the presence of load changes. The proposed controller makes use of only a subset of the state of the system, that is the output voltage and the input current. This paper also presents numerical simulation results which show the performance of the closed-loop system.