Parameter design and experiment of the improved ZVT-PWM Buck converter

To solve the problems of auxiliary switch's hard switching and internal circulating current existing in traditional ZVT(Zero-Voltage-Transition) PWM Buck converter,an improved converter is proposed,in which a snubber capacitor and a diode in series with the resonant inductor are added. Its operational principle is analyzed and each operational stage is introduced briefly. The circuit parameters are designed with experimental study. Results prove that the auxiliary switch achieves near zero-voltage turn-off and the internal circulating current is eliminated,the efficiency of the improved converter is hence enhanced.