Operation Analysis of Fast Charging Stations With Energy Demand Control of Electric Vehicles

For dc fast charging stations (FCS), short charging time duration is its main advantage over other ac charging stations. However, due to the characteristics of internal resistance of electric vehicle (EV) batteries, if charging request of an EV is near the full state of charge (SoC), its charging time increases significantly. In this paper, considering the impact of requested SoC on charging time, we propose an operation analysis of FCS, where operators of FCS can set a limit on the EVs´ requested SoC to obtain maximized revenue. We model the FCS operation as an M/G/S/K queue and incorporate the dc fast charging model into the queuing analysis, as well as the revenue model of FCS. Simulation results indicate that limiting the requested SoC in an overloaded condition at FCS can increase total charged energy and revenue of FCS, as well as decrease the probability of blocking arriving EVs.