Hybrid Mode Optimal Asymmetric Duty Modulation for Dual Active Bridge Converter with DC Blocking Capacitors

To further improve the optimization of a dual active bridge (DAB) converter and enhance the efficiency., a hybrid mode optimal asymmetric duty modulation scheme based on DC blocking capacitors for optimizing the root-mean-square (RMS) value of the fundamental component of inductor current has been proposed. By DC blocking capacitors., the operation of the converter is divided into two modes. By a universal high-frequency-link model, the transmission power and RMS value of the fundamental component of inductor current under each mode are derived. This strategy takes the RMS value of the fundamental component of inductor current as the target, with the transmission power as the constraint, and utilizes numerical methods for optimization. The goal is to minimize the RMS value of the fundamental component of inductor current under the same voltage ratio and transmission power, thereby reducing the overall losses of the converter. Experimental verification of the proposed strategy has also been conducted.