High Step-Down Gain Bridgeless Cuk PFC Converter for Battery Charging Applications

This paper presents a bridgeless Cuk converter topology, designed with a better stepdown capability, suited for Electric Vehicle (EV) charging applications. The proposed topology puts forward a switched capacitor network merged with bridgeless Cuk configuration to offer notable advantages including higher stepdown gain, reduced current stress and enhanced efficiency. Design and operational analysis are derived under Discontinuous Inductor Current Mode (DICM) operation. DICM mode facilitates natural alignment of supply voltage and current utility side, therefore, eliminating additional controlled converters to achieve unity power factor operation. The presented topology is particularly well-suited for on-board battery charging in light EV applications. This paper presents a comprehensive design, modelling and simulation analysis for a proposed topology rated for 600W at 60V. With a switching frequency of 20kHz, the converter demonstrates harmonics-free input current, well in coherence with IEC 61000-3-2.