Integration of electric vehicles into a smart power grid: A technical review

Electrification of a transportation system is one of the most promising alternatives to mitigate the dependency of urban life to fossil fuels. However, introducing a large number of grid-connected vehicles reveals technical problems affecting the entire power system, especially the low voltage section. In this context, this paper presents a review of technical challenges associated with the integration of Vehicle-to-Grids (V2Gs). These challenges are studied in several subsections of a power system such as the operation of power electronics equipment, supply-demand imbalance, and impacts on voltage and frequency. In addition, to clarify the concept of smart grid in a power system, a new definition of a smart power grid in the sector of power distribution is elaborated considering effects of V2Gs. This developed definition specifies that the penetration of V2Gs, in fact, establishes an opportunity for implementing the smart power distribution through offering renewable energy storages, two-way communication, and reactive and active power injections to the grid. This review may be regarded as an important basis for the investigation of future challenges in the integration of electric vehicles into a smart grid.