A Multilevel Active-Clamped Converter Topology—Operating Principle

This paper presents a novel multilevel active-clamped converter topology, which is an extension tomlevels of the three-level active neutral-point-clamped topology. The operating principle is established through the definition of a proper set of switching states and a transition strategy between adjacent switching states. The benefits of the proposed converter topology and control in comparison to alternative multilevel converter topologies are discussed. The simulation and experimental results of a simple four-level dc-dc converter configuration are presented to illustrate the converter performance features. The experimental results of a four-level three-phase dc-ac converter are also presented to further validate the proposed topology and operating principle.