Comparison of High-Power DC/AC Converters for Medium-Voltage PV Power Plants

In the last decade, the total photovoltaic (PV) power installed in the world has been increasing significantly; and, PV plants of hundred megawatts are nowadays in operation. In order to reduce material consumption for the construction of PV systems, a shift to Medium-Voltage power plants is envisaged. In this paper, a comparative study of high-power DC/AC topologies is carried out based on analytical calculation of power losses and stored energy in passive devices. The result shows that the Modular Multilevel Converter (MMC) is the most appropriated technology thanks to its highest power density.