An efficiency improvement study of the full bridge converter at a system load operation

From a DC/DC converter´s system load viewpoint, an efficiency improvement study of the phase shift PWM control full bridge converter operated at a wide load range is presented in this paper. Firstly, the relationship among MOSFET ZVS characteristics, circulating current and loss duty cycle due to the effective primary series inductor is investigated. Accordingly, the power losses estimations of the key components are deduced subsequently. In case of the nominal system load is not operated at a full load condition, some efficiency improved schemes are also provided.