Power quality experiences from Sweden's first MW photovoltaics park and impact on LV planning

摘要

The first 1 MW PV park in Sweden was installed in 2014. A concern from the grid owner perspective is how the growing number of PV installations will influence the power quality in their grids. The power quality impact from the 1 MW park was demonstrated to fall within the regulating limitations in EIFS 2013:1 for the following aspects: voltage changes, voltage harmonics, interharmonics, and voltage unbalance. However, the slow voltage variations were exceeding the Swedish industry recommendations (AMP) governing a single production source. This deviation occurred during 0.74% of the studied two-month period. To meet AMP recommendations it would have been necessary to install a separate cable intended only for the solar park itself and connected closer to the substation. Perhaps a more appropriate alternative would have been to connect the solar park on the closest 20 kV grid.