Comprehensive Optimization of a Dual Active Bridge Converter to Reduce the Current Stress for Battery Energy Storage Applications

This paper introduces a comprehensive optimization strategy for a Dual Active Bridge (DAB) converter, explaining a method for selecting optimized coupling inductance and presenting a novel modulation technique for battery energy storage applications. The main goal of this optimization is to reduce current stress, which can subsequently lower resistance and core losses. This approach primarily concentrates on choosing the appropriate coupling inductance for a DAB converter to ensure the desired power transfer capability for specific applications. A significant contribution of this paper is the introduction of a new modulation technique called Modified Unified Modulation Techniques (MUMT). MUMT integrates the Triple Phase-Shift (TPS), Extended Phase-Shift (EPS), and Single-Phase Shift (SPS) modulation techniques to minimize current stress. The innovation of the proposed MUMT lies in generating a novel current waveform through the inductor, allowing all switches to achieve zero voltage switching and thus reducing switching losses. Additionally, the paper introduces a novel battery management system with MUMT control based on the battery's state of charge (SOC) to ensure smooth operation. The proposed MUMT, combined with optimized inductance values, demonstrates superior thermal performance in terms of conduction loss, switching losses, and overall efficiency.