D02.10 - Multi-Objective Efficiency-Oriented Optimization for DAB Converters Minimizing Current Stress and Backflow Power with Soft-Switching Assurance

Vehicle-to-Grid (V2G) electric vehicle (EV) chargers are becoming increasingly important due to their potential to enhance grid stability, support renewable energy integration, and provide economic benefits, which leads to growing demand for dual active bridge (DAB) bidirectional DC-DC converters. While the current stress and backflow power collectively impact the DAB converter performance, existing optimization methods are mostly single-objective only focusing on one of these two factors – in other words, there is rarely co-optimization to minimize both current stress and backflow power simultaneously. To overcome this limitation, this work proposes a multi-objective efficiency-oriented algorithm that minimizes current stress and backflow power simultaneously by optimizing triple phase shift (TPS) modulation parameters. This is achieved by combining time-domain analysis of the DAB under TPS modulation with an analytical power loss model into an automated holistic digital optimization tool. Compared to the conventional single-objective current stress optimization TPS method, the proposed tool further reduces backflow power and current stress, improving power efficiency by 0.9%.