Voltage control in distribution networks considering area-wide use of regulated distribution transformers

Distribution grids are facing new challenges due to an increasing share of renewable energy sources, especially photovoltaic systems. Critical situations are high power feed-in during low load times in remote areas as this combination leads most likely to voltage band violations. The use of regulated distribution transformers is one approach to keep the voltage in the required limits. This paper investigates its effect on voltage bands in medium voltage and low voltage level and on loading of equipment in comparison to indirect voltage control by reactive power regulation.