Modelling and control of non-isolated high voltage gain boost converter employing coupled inductor and switched capacitor

Abstract

This paper investigates mathematical model of a high gain step-up boost converter built around coupled inductor and switched capacitor. Unlike the classical boost converter, which transfers input power to the output during the switch OFF period, here power is transferred to the output during the switch ON period. A state space averaging method is employed to derive the small signal ac model with ideal components. The control to output transfer function exhibits a non-minimum phase system identical to the conventional boost converter. The derived model is validated via simulation. A dual loop average current mode controller is designed to regulate the converter output voltage. Experimental results taken from a 250W laboratory prototype operating with an input voltage of 20V and output voltage of 190V verify the effectiveness of the controller. The proposed converter is well suited for renewable energy and grid connected power system applications.