Improved steady-state model of the dual-active-bridge converter

An improved steady-state model is developed in this paper for the dual-active-bridge (DAB) dc-dc converter. It is first shown how the well-known ideal model fails to predict DAB dc characteristics, and that differences in model predictions compared to experimental results can be very large, especially in cases where the DAB series tank inductance is relatively small. A new analysis method is then developed and applied to derive an improved steady-state model that correctly predicts DAB dc characteristics. The improved model is validated by simulations and by experimental results.