Integrated approach for power quality requirements at the point of connection

Given the nature of electricity, every party connected to the power system influences voltage quality, which means that every party also should meet requirements. In this field, a sound coordination among technical standards (system-related, installation-related and product-related) is of paramount importance. Further, characteristics of currents (e.g. inrush currents, harmonic currents) should be explored as well their interaction with the voltage. This is also influenced by the impedance of the grid provided by operators. In order to clearly identify responsibilities for voltage quality disturbances on the point of connection (POC), voltage and current requirements have to be available at the POC. Presented in this paper is the relation between inrush currents, flicker severity levels and grid impedances in the low voltage grid. Furthermore maximum harmonic currents at the POC in low voltage grids are determined by using these grid impedances.