The design of full-bridge phase-shifting ZVS switch power supply based on adaptive delay control technology

Abstract

Full-bridge phase-shifting zero voltage switching (ZVS) pulse width modulation (PWM) circuit adopts phase control and by resonance, the circuit can realize zero voltage conduct of switch device, eliminate conduct loss. However, the lagging legs of full-bridge circuit is difficult to realize ZVS in a little current. The main circuit topological structure of full-bridge phase-shifting ZVS high frequency power supply based on adaptive delay control technology is applied in this paper. By adaptive delay control technology, it can detect voltage of power grid and bridge arm midpoint in real time, and expand the ZVS operating range by adjusting the triggered time of switch devices. The main transformer and resonance inductance parameters are designed in this paper. The experimental results proved that adaptive delay control technology can expand the ZVS operating range, and improve the efficiency of the power supply.