Simple load flow control in medium-voltage and low-voltage grids

Abstract:
Feeders that are rapidly integrated into the grid and new loads, can lead to undesirable current and voltage conditions in the individual medium and low-voltage feeders. The situation can be improved by balancing the current flows between high-load and low-load lines. At the medium-voltage level, a standard transformer with a deliberately different vector group is connected between the two unequally loaded outgoing circuits, in series with a stepwise switchable series choke. At the low-voltage level, a step-up transformer is inserted between the two unequally loaded lines, which has a slightly higher voltage on the more heavily loaded side. In both cases, active circulating currents are created which improve at low additional costs the overall load situation.