Report on efficiency of field-installed PV-inverter with focus on radiation variability

Performance of photovoltaic systems greatly depends on climate conditions. Apart from values of solar radiation, its variations can also have an influence on energy yield from a PV-system. In less favourable climate conditions (e.g. in central Europe), highly varying radiation is very frequent and the electrical converters (i.e. inverters, DC-DC converters) should be able to follow the irradiance changes with their maximum power point tracking algorithms. The paper presents the dependency between variation of the solar radiation values and the efficiency of grid-connected inverter operating in a photovoltaic installation. One-year data from measurements of field-installed PV-system is utilized in the calculations.