Voltage quality parameters in LV distribution grids in dependence on short circuit impedance

The supply territory of the company E.ON Distribution in the Czech Republic (operated by the company E.ON Czech Republic) accounts for approximately 1.5 million customers, the most of them are connected to the low voltage (LV) distribution grid. The goal of this paper is to describe problems of voltage quality in the LV distribution grid, if exist. The survey is based on the evaluation of approximately 450 voltage quality (VQ) measurements which were made in points of LV grid with known short circuit impedance phase-earth. This short circuit impedance was measured in the each point of made VQ measurement. So it is possible to demonstrate the dependence of selected VQ parameters on phase-earth short circuit impedance by means of graphs.