Dynamic modeling and design of a Cúk converter applied to energy storage systems

This paper presents the study of a Cúk converter as a battery charger in clean energy systems. In some applications like fuel cell and photovoltaic systems the converter input current ripple is desired to be reduced. As a battery charger, the converter should have a reduced output current ripple as well. The Cúk converter can achieve the reduction of both input and output current if the inductors of the circuit are properly designed. In a Cúk converter neither the input current nor output current are pulsed, which is good for the source and for the load. In addition, the Cúk converter can operate in step-down or step-up modes, according to the duty cycle. Dynamic modeling and the design of a 500 W Cúk converter fed by a 50 V power source and connected to a 24 V battery bank in the output are presented herein. The obtained models are validated using simulation.