A Novel Topology Derivation Method Revealed From Classical Cuk, Sepic, and Zeta Converters

The classical Cuk, Sepic, and Zeta converters have found wide applications in various fields. However, there has been limited research exploring their relationships. This letter aims to uncover their relationships by focusing on their capacitor-less circuits (CLCs). Initially, it is observed that these three converters exhibit highly similar performance characteristics, such as equal voltage gains and average component currents. Subsequently, this letter establishes that their equivalent CLCs are the reason behind these similarities, presenting a new perspective on understanding dc-dc converters with capacitors. Furthermore, based on the above findings, a novel topology derivation method is proposed by connecting capacitors to a CLC. Compared with the traditional methods, the proposed method can derive families of converters with comparable performance. Moreover, the proposed method is particularly suitable to leverage existing converter designs and modify them to meet specific requirements. The proposed method successfully derives several groups of converters from different CLCs. For a group of converters derived from an equivalent CLC, their effectiveness and their performance relationship are verified experimentally. © 2024 IEEE.