Conversores CA-CC trifásicos isolados com único transformador excitado pela tensão de modo comum e com comutação suave.

Abstract

This work proposes two new soft-switching, isolated, three-phase AC-DC converter topologies that introduce a novel concept: the intentional use of common-mode voltage—derived from connecting the DC bus midpoint to the converter neutral—as the excitation variable for a single high-frequency transformer. For both proposed topologies, the operating principles are presented, alongside a mathematical description covering their modeling, modulation and control strategies, and the design of the controllers employed. The theoretical analysis is verified through computational simulations and tests performed on experimental prototypes. The results obtained validate the proposed topologies.