Pareto-Optimal Design Method for DAB Converter Considering Balanced Performance Across Wide Operating Ranges

An optimal design method for a Dual Active Bridge converter for EV chargers is proposed in this paper, in which both design and control degrees of freedom are utilized to achieve high-efficiency operation across the entire voltage range. Feasible ranges for the transformer turns ratio and leakage inductance are defined, and the loss characteristics associated with each parameter combination are evaluated through numerical analysis based on harmonic decomposition. The losses at the rated condition and worst condition are defined as two cost functions, and Pareto optimization is used to determine the optimal design parameters by balancing their trade-off. The proposed design process is experimentally validated, achieving over 97% efficiency across the full operating voltage range and a peak efficiency of 98.05% at the rated condition.