Simulation and design of 25 kw modular dual active bridge (DAB) DC-DC converter for EV chargers

Abstract

The growing demand for efficient, scalable, and reliable electric vehicle (EV) charging infrastructure has catalyzed interest in advanced power electronics topologies. Among these, the Dual Active Bridge (DAB) converter stands out due to its bidirectional power flow capability, galvanic isolation, and high efficiency across various operating conditions. However, a modular architecture for DAB converters becomes essential as power levels and complexity increase, particularly in fast-charging applications. This Thesis advocates for the use of a modular DAB converter architecture in EV chargers, emphasizing its advantages in scalability, fault tolerance, thermal management, and ease of maintenance. A modular approach enables the construction of high-power chargers by paralleling multiple lower-power DAB modules, offering design flexibility and cost-effective scaling. This not only supports future growth in EV adoption and charging demands but also simplifies the customization of charger output power for different applications. Additionally, redundancy can be incorporated into the modular design, allowing the charger to continue operating at reduced capacity in the event of a module failure, thereby improving system reliability and availability. Modular DAB systems also facilitate distributed thermal management and reduce current stress on individual components, enhancing overall efficiency and lifespan. Furthermore, modularity simplifies maintenance and replacement procedures, minimizing downtime and operational disruptions. In conclusion, the modular architecture of the DAB converter aligns well with the evolving requirements of EV charging infrastructure. It provides a robust and adaptable platform that can meet the increasing power demands while ensuring high efficiency, operational resilience, and long-term serviceability. As the EV market continues to expand, adopting modular DAB converters in charging stations will be pivotal in building a sustainable and future-ready energy ecosystem.