Assessment of plug-in electric vehicles charging impacts on residential low voltage distribution grid in Hungary

Abstract

The growing concerns over greenhouse gas emissions coupled with the improvement of electric vehicle technology have encouraged the electrification of the transportation sector. Plugin electric vehicles (PEVs) are becoming an alternative to vehicles powered by an internal combustion engine. This leads to environmental benefits, but these PEVs represent new challenges facing the power grid. Therefore, the power grid must be prepared for these challenges. This paper provides a comprehensive study of PEVs charging impact on the low voltage distribution grid. For this purpose, a typical Hungarian low voltage grid was modeled in DIgSILENT Power Factory. Two charging scenarios have been studied, uncoordinated charging and delayed charging. Three penetration levels of PEVs are considered in this paper as follows, 20%, 40%, and 60% Time sweep analysis is used to investigate transformer loading, feeders loading, voltage deviation and system total losses. The results show that at 60% penetration level with uncoordinated charging, both the distribution transformer and feeders thermal loading violation is experienced. On the contrast, with the delayed charging, all the grid components function at their normal rating at all penetration levels and no network upgrade is required.