High frequency Zero-Voltage-Switching H5 Inverter for Distributed Grid-connected System

Power electronics-interface converters with higher switching frequency and conversion efficiency are preferred to improve the performance of distributed generators and provide auxiliary service for distribution networks, such as dynamic response, compensable harmonic spectra and reactive power, et al. This paper presents a Zero-voltage-transition (ZVT) resonant tank structure for the H5 topology to realize zero-voltage-switching for high frequency main switches, and further to create the feasibility of pushing the switching frequency up. By combining and simplifying the basic resonance cells, a simple and compact ZVT-H5 topology is derived, which realizes zero-voltage turn-on and turn-off for the high frequency main switches, and zero-current turn-on for the high frequency auxiliary switches, and the reverse recovery problem of the freewheeling diodes is also avoided. Finally, the detail operation principle and the experimental results from a 3 kW prototype at 100 kHz switching frequency are provided to verify the effectiveness of the proposed ZVT-H5.