On the compensation of Non-active Current Components of Three-phase Loads with Quickly Changing Unsymmetry

摘要

Some types of loads, like arc furnaces, present a special challenge to compensation strategies. They vary quick- ly and have a very high rated power. For example the arcs of an arc furnace are not burning continuously es- pecially when starting the melting process. This causes variations of the line voltage with frequencies well below the line frequency commonly known as voltage flicker. Because of cost efficiency the energy storage ca- paility of compensators for the mitigation of voltage flicker effects can still only be small compared to the en- ergy taken by the arc furnace during one period of the line voltage.