High-Gain Cuk DC-DC Converter with Switch-Capacitor and Switched Inductor: A Non-Isolated Design

Abstract

This work introduces the DC-DC topology of a non-isolated high-gain step-up Cuk converter. The proposed topology is based on implementing switched-capacitor (SC) and switchedinductor (SL) techniques. The primary focus of this topology is the application in renewable energy systems and electric vehicles, specifically in photovoltaic and fuel cell technologies. The proposed topology exhibits a notable enhancement in voltage boost capability when compared to the traditional boost and Cuk converters, owing to the implementation of SC and SL approaches. The suggested Cuk converters are obtained by modifying the original Cuk converter, wherein the single inductor present at the output and input sides is substituted with an SL, and the energy-transferring capacitor is replaced with an SC. The primary benefits of the recommended Cuk converters lie in their ability to achieve a high output voltage gain and mitigate the voltage stress experienced by the power switch. Hence, it is possible to utilize a MOSFET with a lower voltage capacity, resulting in a lesser Rds-ON and increasing efficiency. A comparison has been made between the voltage gain and voltage stress across the primary switch in the proposed converter and the Cuk and boost converter. The recommended topology is intended to circumvent the need for a transformer, coupled inductors, or severe duty cycles. This design approach results in reduced volume, loss, and cost. The proposed converter is evaluated under the continuous conduction mode. The present study provides a theoretical investigation of the continuous conduction mode, whereby all relevant expressions are derived and compared with the corresponding simulation results.