In the effort to increase the share of renewable energy especially small and medium energy sources like wind and photovoltaic generators play an important part as do plug-in hybrid electric vehicles and all-electric vehicles. These new network participants introduce additional power flows into the existing electric power network. Increasing voltage variations particularly in rural low voltage networks with low customer density will occur. Smart electric grids provide an alternative to costly network reinforcement because they are able to control power flow at certain intervention points. This...