An Isolated Gate Driver for Multi-Active Bridges with Soft Switching

Abstract: The design of gate drivers is an important topic in power converter topologies that can help reduce switching losses and increase power density. Gate driving techniques that offer zero-voltage switching and/or zero current switching have recently been successfully proposed for different modular multilevel converters such as the cascaded H bridge. Previous papers on other multilevel converters such as the multi-active bridge, however, do not sufficiently assess the topics of gate driver design for this topology. This work presents a novel isolated gate driver architecture tailored to the multi-active bridge topology. Zero voltage switching is then achieved using two multi-winding transformers. The advantages of the proposed topology are not only a reduction of switching losses but also reduced component count. The topology is evaluated on a prototype using experimental results. It was shown using simulation and experiments that the proposed topology has a high efficiency while providing compact power packaging. Especially for converters with many levels, the proposed topology is therefore advantageous compared to existing solutions.