Reassessing the real world simultaneity factors for solar and wind feed-in for a medium-voltage grid

Abstract:
For power system planning in medium-voltage grids power flow calculations with simultaneity factors for feed-in and consumption powers are common practice to determine grid stability and selecting connection points for new consumers and power plants. Together with the distribution system operator EAM Netz GmbH the currently used simultaneity factors for solar and wind feed-in were compared to newly determined simultaneity factors. Comparing the newly determined simultaneity factors for solar and wind feed-in with the ones currently used at EAM Netz shows that they are close enough so that the currently used factors can be used for future power system planning. Together with the simultaneity factors for solar and wind feed-in, the correlation of the ratio of installed solar generation power to installed inverter power, i.e. overinstallation, on the the maximum feed-in was analyzed, with the result that this factor should be taken into account for power system planning. With more installed solar and wind power plants the method described in this paper can be used to update the simultaneity factors periodically, to spot any changes regarding the feed-in profiles of solar and wind power plants.