An interleaved flyback micro inverter with H5 topology for photovoltaic applications

Abstract

The photovoltaic (PV) power conversion is one of the most extensively studies research areas among renewable energy sources. The inverters that are indispensable in terms of power conversion process have also been improved for interfacing ac applications and ac grid integration of PV systems. One of the recent inverter topologies used for connecting the solar PV plants to utility grid and ac loads is micro inverter which is capable to provide maximum power point tracking (MPPT) control for each solar module through the PV plant. This study proposes a new micro inverter topology which is defined as IFMI due to its configuration comprised by interleaved flyback microinverter (IFMI). The micro inverter has been implemented in two-stage structure where the dc-dc power conversion is accomplished by two-phase interleaved flyback converter while the ac conversion stage is comprised by H5 inverter topology. The dc-dc converter stage has been controlled by conventional incremental conductance MPPT algorithm. The controller of H5 inverter is improved with sinusoidal pulse width modulator and PI controller. Simulation and experimental results verify the stability of power conversion and reference tracking of proposed converter. Detailed analysis has been presented and discussed for pros and cons of proposed device topology with future work prospects.