Efficient Control Strategy for Circulating Current Minimization in Dual Active Bridge Applications

Abstract

This research thoroughly examines control strategies for the isolated dual active bridge (DAB) isolated bidirectional dc-dc converter (IBDC), introducing an advanced switching method designed to optimize performance. The proposed method’s effectiveness is validated through a comprehensive evaluation involving theoretical analysis, simulations, and experimental testing. This article addresses the limitations of conventional phase shift techniques, notably their issues with circulating currents and current stress, by developing a technique offering a 3° flexibility, thereby significantly reducing circulating currents. This reduction leads to lower power losses and substantially improves efficiency beyond what traditional phase shift controls achieve. In addition, the research pioneers a method for enabling smoother switching within the DAB system, similar to DPS, effectively widening the zero voltage switching (ZVS) range. This innovative control strategy’s practical application and superiority are decisively proven through experimental validation on a 2.4 kW DAB prototype, showcasing its potential to redefine bidirectional dc-dc converter efficiency.