A high efficiency PV micro-inverter with grid support functions

This paper presents a new photovoltaic (PV) micro-inverter topology. The topology is based on a partial power processing resonant front end dc-dc stage, followed by an interleaved inverter stage. The input stage provides high efficiency, and flexibility of design for wide input voltage range and the output stage provides an effective switching ripple of twice the PWM frequency, which reduces the output filter requirement. The designed micro-inverter can also provide grid Volt/VAR support functions according to commands received by the grid. Circuit topology and operation are presented as well as experimental results for the micro-inverter. The overall micro-inverter efficiency is 96%.