Performance and losses analysis of charging and discharging mode of a bidirectional DC/DC fullbridge converter using PWM switching pattern

Bi-directional isolated on-board chargers are potential options in grid-connected vehicle applications in the future smart grid environment. For a two-stage bi-directional on-board charger consisting of an AC/DC converter and an isolated DC/DC converter, performance analysis has been conducted for the DC/DC stage. The DC/DC converter has full-bridge topology where the loss analysis has been done for different switching devices, transformer and inductor and for different operating points in both directions. A robust controller is designed for DC/DC converter to prevent the battery voltage overshoot. This DC/DC stage has a high efficiency figure, around 95%, in both battery charging and battery to the grid power transfer modes.