Inverters for grid connection of photovoltaic systems and power quality: Case studies

The Power Quality (PQ) issues are here assessed from an experimental point of view concerning the grid-connected PhotoVoltaic (PV) systems. After an introduction to the new regulations for smart grid connection in presence of Distributed Generators, the work concentrates the attention on a variety of power inverters both in normal and in unusual operation. In particular the PQ problems in case of shading effect on the PV modules are highlighted. The corresponding increase of harmonic content and unbalance, together with the decrease of power factor, is assessed in the paper.