Modeling the frequency response of photovoltaic inverters

The increased presence of photovoltaic (PV) systems inevitably affects the power quality in the grid. This new reality demands grid power quality studies involving PV inverters. This paper proposes several frequency response models in the form of equivalent circuits. Models are based on laboratory measurements performed on five different commercially available PV inverters, and fitted to obtain circuit parameters. The proposed models are in good agreement with the measured data.