Effects of state estimation accuracy on the voltage control of low voltage grids

The increased integration of distributed generators (DG's), especially the residential-scale photovoltaic (PV) units in the distribution grids, causes different problems regarding the loading of the grid components, particularly at medium and high voltage levels. There is also an issue regarding the violation of the allowable voltage range, most notably at low voltage levels. The voltage violation problems can be mitigated either by traditional grid reinforcement measures or by the application of intelligent voltage control strategies. In this paper, three different voltage control strategies based on the grid states (voltage magnitude and its phase angle at every node) obtained from a state estimation (SE) algorithm are introduced and their performance is analyzed. A simulation model of a real German low voltage (LV) grid is used as the basis for the analysis. Furthermore, the effect of estimation accuracy of the grid states on the efficiency of voltage control strategies in LV grids is investigated.