Power management of EV car parks

Clean energy has become increasingly important in different countries and Electric vehicle (EV) are commonly viewed as part of the solution. EV sales are steadily increasing and there is now much focus on the infrastructure to charge them. This paper is focused on public and private EV car parks where installing an increasing number of charging stations, with growing power requirements due to faster-charging technology, is a burden to the electrical grid. It is often the case, that for either technical or commercial reasons, that the power feed for the car park is restricted or it is advantageous to dynamically manage the peak power to reduce electrical costs. In this paper, an EV car park is modeled that contains a defined number of rapid chargers with a limited incoming power supply. Using real traffic data simulations, the power feed demand profile can be obtained. This study proposes four methods to manage the charge of EVs when the power feed is limited in capacity resulting in a necessary sharing of power. Simulation results show that by controlling the charge rate of each EV the overall power limits can be met. Furthermore, it is shown that the method chosen can be used to influence the variance in SOC across all EVs.