Design Considerations for Gan-Based Microinverter for Energy Storage Integration Into Ac Grid

A full bridge converter with electrolytic capacitor on the dc bus is a widely used approach for a single phase interface for renewable energy source generation or energy storage integration in the utility grid. New wide bandgap devices enable higher switching frequency, higher efficiency and higher power density. In the paper, the authors introduce the challenges associated with an increase in switching frequency of a single phase inverter and implementation of wide bandgap GaN-based transistors instead of traditional Si-based transistors. The low gate threshold voltage of GaN transistor and unique reverse conduction behaviour require different driving circuit. The design of the driver circuit and other practical issues are analysed in the paper. The paper also presents some practical results. The research results can be useful to avoid mistakes by designing GaN-based power converters as these devices become increasingly interesting for commercial applications.