Optimisation of HV/MV-transformer-voltage-control in distribution networks with a high proportion of distributed generation

The power supply from many small decentralised power generation plants (DPG) is increasingly influencing the voltage quality in the distribution networks. The further expansion of the decentralized energy plants is expected to lead to a worsening of the situation. The need to further expand the German distribution network, a need forecast by the BDEW (the German Energy and Water Authority) has given rise to the necessity to look for fast, cheaper and innovative solutions to reduce the negative effects on the power supply of the power generation plants on the MV and LV network levels. Within the framework of a pilot project carried out by the LEW Verteilnetz GmbH, it was examined whether the maintenance of the voltage level in the MV network could be improved with the help of an optimised voltage regulator of the HV/MV transformer, at the same time remaining in the stipulated limits. The LEW Verteilnetz GmbH (LVN) is a regional network operator in Bavaria and a subsidiary of Lechwerke AG based in Augsburg. The network area of Lechwerke includes Bavarian-Swabia as well as parts of Upper Bavaria.