Dual mode modulation method for the full-bridge converter operating in a wide input voltage range

To improve the efficiency of full-bridge converter operating under wide input voltage conditions, this Letter proposes a dual mode modulation method. The full-bridge converter is controlled by phase-shifted mode at low input voltage and asymmetric pulse width modulation mode at high input voltage. The proposed method can reduce power loss, voltage stress of rectifier and output filter requirement. A 500-W full bridge converter with a 160 to 400 V input voltage range is built to confirm the validity of the proposed dual mode method.