A Zero-Voltage Switching (ZVS) grid-connected full-bridge inverter and its modulation schemes are investigated. A novel sinusoidal pulse width modulation scheme for the ZVS full-bridge inverter (ZVS SPWM) is proposed in this paper. The ZVS SPWM is evolved from the double-frequency (DF) SPWM by adding gate drive to the auxiliary switch. The ZVS condition is analyzed and the circulation loss of the resonant branch is optimized by adjusting the energy storage in the resonant inductor. The reverse recovery of the body-diode of MOSFET is relieved and ZVS is realized for both main and auxiliary switches. The filter inductors are significantly reduced with higher switching frequency. The design guideline of resonant parameters and the implementation of ZVS SPWM in DSP controller are introduced. The ZVS SPWM scheme is verified on a 3kW inverter prototype. According to the experimental result peak efficiency as 98.8% is achieved. Index Terms-Zero-voltage switching (ZVS), pulse width modulation, full-bridge inverter

A Zero-Voltage-Switching (ZVS) PWM scheme for full-bridge inverter with active-clamping technique is proposed. The ZVS condition is analyzed and the ZVS PWM scheme is designed to realize zero voltage switching for both main switches and auxiliary switch in a large power range. The ZVS PWM scheme also adjusts the energy stored in resonant inductor with variation of load to reduce the circulating loss in light load range. The switching frequency is increased and the filter inductor is significantly reduced. The experiment on a 3kW prototype shows the realization of ZVS and high efficiency. Index terms-Zero voltage switching, full-bridge inverter, ZVS PWM

Although SiC MOSFET has significant improvements on switching performance compared with traditional Si power devices, the dynamic loss of the converter rises with the increase of the switching frequency of the converter. To further improve the efficiency of SiC inverter and power density, Zero-Voltage-Switching (ZVS) is investigated. A SiC full-bridge inverter with ZVS-switching is presented. The efficiency of SiC MOSFET ZVS full-bridge inverter is compared with that of hard switching SiC inverter at different switching frequency. Finally it is shown that the ZVS-Switching inverter is preferred in high switching frequency.