Design Optimization of GaN-Based Dual-Active-Bridge Converters for Datacenter Applications

The design methodology of dual-active-bridge (DAB) converter using gallium nitride (GaN) device is presented in this paper. Compact, reliable, and efficient power conversion is required for the rising demand of the behind-the-meter-storage (BTMS) for datacenters and high-power charging stations for electric vehicles (EVs). Having inherent soft switching operation capability for high efficiency, and high-power density, DAB topology is selected for this application. The systematic design of DAB converter is presented which focuses mainly on obtaining the best efficiency. The transformer design is incorporated in the optimization to get the optimum leakage inductance while maintaining the zero-voltage switching (ZVS) and minimizing the transformer losses. Besides switching frequency sweep performed among available GaN devices, various parameters from the devices-such as terminal parameters and gate characteristics-are evaluated for the performance optimization to achieve best efficiency over the operating region of the datacenters. The simulations and experimental verifications are provided to validate the design methodology.