Comparison and Analysis of Transformer-less Topologies for Grid-Connected PV Systems

With solar photovoltaic (PV) systems, solar energy is converted into electricity with the least impact on the environment. PV Systems are a promising source of renewable energy. A PV inverter without a transformer includes many advantages, including high efficiency, high reliability, low weight, and low size. Leakage currents at such topologies, therefore, are unfavorable, so they must be eliminated. Inverter topologies with more semiconductor switches are a good way to eliminate leakage currents. The paper reviews analyze and compare several recent topologies published regarding renewable energy sources. A comparison is made among the topologies considering leakage current, semiconductor losses, and total harmonic distortion.