Modeling and Analysis of Voltage Overshoot in Bidirectional Phase-Shift Full Bridge Converters

To achieve high power density and efficiency in an isolated bidirectional DC/DC converter on DC microgrid, bidirectional phase-shift full bridge (PSFB) converter is employed in this paper. However, the PSFB converter exhibits a significant voltage overshoot on the secondary side of the transformer, which increases the voltage stress on secondary side switches. This paper proposes a simplified model to predict and characterize this voltage overshoot and explains the detailed circuit operation, as well as the corresponding mathematical derivations. The model can be used to evaluate the voltage overshoot and explore voltage suppression techniques, providing insights into the circuit behaviors.