Design and prototyping of transformerless DC-DC converter with high voltage ratio for MVDC applications

Abstract

Power boost DC-DC voltage converters have become a key element for medium-voltage DC (MVDC) applications as a link between generation and distribution grids, it is possible to classify the DC-DC converters into four families, depending on their characteristics, as well, one of the actual principal needs is to reduce the number of passive and active components needed for voltage conversions. This article presents a novel transformerles DC-DC boost-resonant converter, which is destined for the interconnection of medium and high voltage DC smart grids. The proposed DC-DC converter is composed of two inductors, a capacitor, and five IGBTs interrupters, which are responsible for the interaction between resonant and boost converters, in the same way, the resonant converter is composed of one resonant inductor and one resonant capacitor while the boost converter is composed by one boost inductor. This paper also presents the operation principle of the proposed converter, as well as its control, modular connection, and simulation to probe the behavior of the converter and an experimental 100 W prototype with 9.5 gain.