Impact and cost evaluation of electric vehicle integration on medium voltage distribution networks

This paper presents the analysis of the impact of electric vehicle (EV) integration on medium voltage (MV) distribution networks and the cost evaluation of replacing the overloaded grid components. A number of EV charging scenarios have been studied. A 10 kV grid from the Bornholm Island in the city area has been used to carry out case studies. The case study results show that the secondary transformers are the bottleneck of the MV distribution networks and the increase of EV penetration leads to the overloading of secondary transformers. The cost of the transformer replacement has been evaluated. The transformer replacement cost reaches 72% of the total transformers value with 50% EV penetration and 3 Phase charging.