Peak Current Control and Feed-Forward Compensation of a DAB Converter

The double active bridge (DAB) converter has been proposed in different applications due to its advantage of wide soft-switching range and power flow regulation capability. Applications like hybrid or electric vehicles and avionics systems require a fast dynamic response since the demanded power depends on the driving, which becomes an important factor for safety. Additionally, due to unbalance in the components, a dc offset may be applied to the transformer; therefore, the risk of saturation is possible. This article presents a double band current control for the DAB converter that permits to avoid the risk of transformer saturation. Additionally, feed-forward compensation is employed to achieve a very fast transient response under load and input voltage variations. The proposal is described, analyzed, designed, simulated, and experimentally tested.