Proposal of a Photovoltaic AC-Module With a Single-Stage Transformerless Grid-Connected Boost Microinverter

Microinverters for photovoltaic (PV) modules can improve the energy generation by reducing the effects of shading, since the energy harvesting of each PV module can be controlled individually. In this context, this paper presents a topology of single-stage transformerless grid-connected boost microinverter. It promotes high voltage gain without using a preregulator circuit or a high/low-frequency transformer. A 500 W laboratory prototype was implemented and experimental tests were carried out so that the proposed microinverter was evaluated in a grid-connected PV system. Experimental analysis was performed in order to corroborate the theoretical approach and to verify the effectiveness of the proposed modified Perturb and Observe Gama maximum power point tracking technique and the proportional-resonant (P-Res) grid current controller under different irradiation conditions and under partial shading.