Design and analysis of a grid-connected inverter without isolation for an AC module

Among the photovoltaic (PV) systems, the ones interconnected to the electric system have presented a greater growth in the developed countries. In order to transform the generated DC energy in AC energy ready to be delivered to a grid, the concept of AC Module is applied. However, the problem of generating quality voltage to the network from a single PV module arises. As a solution, the topology of the buck-boost converter with tapped inductor (TI) is studied. The purpose is selecting a converter appropriated for an integrated PV inverter, with high benefits without isolation, applied to residential use with connection to a single-phase grid. Its performance is evaluated by means of the electronic simulator PSpice and it is verified with a prototype. From the collected data it is appreciated that the proposed inverter increases the voltage gain and the efficiency with respect to traditional converter.