Conduction Loss Reduction Method for Active Clamp AC-DC Flyback Converter by Triangular Current Mode

This paper proposes a resonant current reduction method by the Triangular Current Mode (TCM) for an active clamp AC-DC flyback converter. An active-clamp flyback converter has been widely considered because of Zero Voltage Switching (ZVS) by the active-clamp circuit. However, the resonant current increases the conduction loss of the flyback converter. The proposed method reduces the resonant current by adjusting the switching pattern of the active clamp circuit. Moreover, TCM is applied to achieve ZVS for the switching loss minimization. Experimental results show that the fly-back converter achieved ZVS by TCM control. Finally, the conduction loss of the active-clamp AC-DC flyback converter was reduced by 5.6%.