Defining Operating Ranges for Efficient Magnetic Design in Dual Active Bridge Converters

Abstract

Dual active bridge (DAB) converters play a crucial role in high-power applications such as electric vehicles, renewable energy systems, and grid-tied converters due to their ability to provide bidirectional power transfer, high efficiency, and galvanic isolation. However, the pursuit of higher power density in these converters often necessitates increased operating frequencies, creating challenges in magnetic component design due to semiconductor thermal limitations. Traditional approaches, such as detailed thermal modeling and experimental methods, are time-intensive and impractical during the initial design stages. This paper presents a rapid analytical method to establish feasible operating frequencies and inductance ranges for DAB converters based on semiconductor thermal constraints, utilizing readily available device datasheet parameters and application-specific data. The proposed method omits complex thermal models and experimental procedures, streamlining the early-stage design process for magnetic components while maintaining thermal compliance. A real-time hardware-in-the-loop model was developed to validate the proposed method across power levels from 10 kW to 30 kW, demonstrating safe operation within thermal limits. The findings underscore the potential of this method to provide timely, practical guidance for magnetic designers, reducing iteration cycles and associated costs while setting the stage for further optimization and control refinement in DAB converter systems.