An Overview of Converter Topologies and Their Derivations and Interrelationships

Canonical switching cell is known as the basic building block of dc-dc buck, boost, buck-boost, Ćuk converters, voltage/current source inverters (VSI/CSI) as well as multilevel converters (MLCs). This article reveals the existence of another basic switching cell as a singular structure of the canonical switching cell. The proposed new basic cell can constitute single-ended primary-inductor converter (SEPIC), Zeta converters, and Z-source converters. Each of the basic switching cells has the simplest form with two complementary switches, one inductor and one capacitor. An approach to construct a dc-dc converter by connecting source/load to the basic switching cells’ terminals is demonstrated. Some existing topologies of dc-dc converters are correlated following the proposed approach. Further, this article reviews Z-source/quasi-Z-source (qZS) converters, universal converters, and multiple-source converters to uncover some general approaches for topology manipulating. Z-source/qZS converters and the emerging classes of universal converters are used as examples to demonstrate the incorporation of their switches. Multiple source converters are fabricated by combining basic switching cells, in both the voltage source and current source form, using the duality principle. With the ever-increasing research efforts on converter topologies, it is hoped that this article will improve the understanding of the existing converter relationships and inspire insights for new topological developments and applications.