Electric vehicle charging infrastructure, standards, types, and its impact on grid : a review

Abstract

The growth of EV penetration brings numerous benefits in economic and environmental aspects, but it also presents deployment opportunities and challenges of EV charging stations. The EV owners benefit from lower fuel and operating expenses compared to ICE vehicles because of higher efficiency of electric motors reaching it as high as 60–70%. The electric vehicles are intermittent load to the grid since the number of users charging the electric vehicle at different charging station at different time. Moreover, the increasing EV penetration leads to the increase in load requirement on charging stations and will place a heavier load on the grid, necessitating the exploration of alternative resources. So, it significantly effects on power quality of the distribution grid. This charging requirement needs to be effectively managed to ensure uninterrupted energy supply for charging EVs batteries. By employing a basic charging plan, the estimated system cost per vehicle per year in Denmark is $263. Implementation of smart charging, the system cost decreases to $36 per vehicle per year, resulting in substantial savings of $227 per vehicle per year. Controlled charging methods also effectively reduce system costs by 50% and decrease peak demand. An EV fleet has the potential for cost savings in the power system, amounting to $200–$300 per year per vehicle. The aim of the review is to address the impact on power quality of the distribution grid and study the nature of EV unbalanced loads in order to minimize impact on grid efficiently by managing the resources.