Voltage Impacts of DG on Distribution Grid with Voltage Regulators and SVCs

Interconnection of the Distributed Generation (DG) at higher penetration levels to the distribution grid is causing different problems with voltage profile of a typical distribution feeder. In this paper some of the voltage problems caused by increasing penetration of DG along with the role of the Volt-VAr controlling devices to mitigate these problems are investigated and discussed. A real distribution circuit containing a synchronous generator, a line voltage regulator, and a Static VAr Compensator (SVC) was used for computer modeling. Simulations were conducted considering full load and light load conditions, without, then with DG at various penetration levels. Simulations´ results verifying the high voltage conditions and unacceptable voltage flickers due to increased penetration of DG have been presented. It was also concluded that voltage regulator with certain settings and SVC can mitigate some of these problems.