Projeto e desenvolvimento de um novo inversor solar de estágio único sem transformador adequado para aplicações de baixa potência

Abstract

The aim of this thesis is to present a study on solar microinverter that, in its turn, are powered by photovoltaic modules and can improve power generation by reducing the shading effects, since the capture of each photovoltaic module (PV) can be controlled individually. A novel single-stage dc-ac converter topology without a low or high frequency transformer that operates with the output voltage and input currents waveforms totally controlled were presented (Single-Stage Transformerless Boost Microinverter - STBM). Moreover, the proposed converter promotes a high voltage gain without using a pre-regulator or transformer, reducing the weight and size of the inverter physical structure. The simulation and experimental analysis were performed for verifying the tracking factor of the proposed MPPT technique P&O Modified “Gama” and the grid injected current controller Proportional-Resonant (P-Res) on a grid-connected system (STBM). Tests were performed with the system operating with the Solar Array Simulator (SAS) and under real operating conditions with the PV modules installed on the laboratory’s roof. The P-Res controlled with Harmonic Compensators and the STBM leakage current were also evaluated. The simulation and experimental results of the developed STBM prototype intend to meet the Brazilian and International Standards.