Harmonic modelling of solar inverters and their interaction with the distribution grid

Excessive harmonic distortion has been reported in some distribution grids with a high number of photovoltaic inverters. In this paper, a simple model is introduced to describe the interaction between grid components and groups of inverters which can lead to amplification of harmonic voltages. The model is validated by using extensive measurements for several types of commercially available photovoltaic inverters. The measurement setup and method are described and the results are presented.