A 1.6 kW GaN PV Microinverter with two MPPT Ports

This paper proposes a novel high-efficiency and high-density GaN PV microinverter with two MPPT ports. The novel microinverter combines a Buck-Boost DC/AC stage and an unregulated resonant converter to provide galvanic isolation and voltage gain. The dual-mode operation of the Buck-Boost is utilized to reduce the total loss. The unregulated LLC resonant converter utilizes 650V E-mode GaN FET AC switches and always works at the resonant frequency to achieve very efficient conversion with ZVZCS. A 2-port all-GaN 1.6 kW microinverter prototype is developed and demonstrated. The power density is 50W/in ³ which is much higher compared with the state-of-the-art PV microinverters.