Modeling and Simulation of Switching Modes of Dual Active Bridge Converters for Interfacing Supercapacitor

This paper investigates the application of alternative switching modes in the Dual Active Bridge (DAB) dcdc converter to enhance its operational efficiency in supercapacitor (SC)-based energy storage systems (ESS). Due to SCs’ low voltage and high current characteristics, they present a challenge for DAB since the converter needs to operate under a high voltage conversion ratio. To address these challenges, this study employs discontinuous conduction mode (DCM) switching, which introduces a zero-crossing time (ZCT) interval during switching transitions which facilitates zero current switching (ZCS) and reduce conduction losses. Additionally, the elimination of specific switching transitions under low-voltage operating conditions enables consistent ZCS, further minimizing switching losses. This approach is particularly advantageous in configurations involving a high-voltage primary and a lowvoltage, high-current secondary. Analytical modeling and steadystate derivation are provided to characterize the current and power behavior under different switching modes, and the theoretical findings are validated through simulation. The results demonstrate that DCM operation significantly mitigates power losses at low SC voltages, confirming the effectiveness of ZCT-toZCS transition in enhancing DAB converter efficiency for SC applications.