A Current-Stress-Optimized Design Method for Dual Active Bridge Converters with Improved ZVS Capability under Wide Output Voltage Conditions

In dual active bridge (DAB) converters, the current stress seriously impacts the switching losses, and thus is tightly relevant to the efficiency. This article proposes a design method for the parameters of magnetic components, i.e., the inductance and the turns ratio of DAB converters, which is on the basis of an optimal triple-phase-shift control. The objective of this method is to minimize the current stress to the utmost extent and ensuring the soft switching under specific wide output voltage conditions, thus greatly improving the efficiency. At beginning, a mathematical model of the current stress is established in this article. Then, the optimization method of the parameters of magnetic components is classified into two cases according to the given operating conditions, and the boundaries and constraints of both cases are presented. Finally, an intuitive design process of magnetic components is presented. The effectiveness of the proposed design method is verified by experimental results.