Flexible Charging Coordination for Plug-in Electric Vehicles based on Uniform Stochastic Charging Demand and Time-of-Use Tariff

In this study, a novel flexible plug-in electric vehicles (PEVs) charging coordination scheme is proposed for the multi-charger station of an office building. Based on uniform stochastic charging demand (USCD) analysis of the PEVs in the building, charging time of PEVs can be prioritized with their arrival times and parking durations to mitigate the service conflicts during high demand. Also, charging time can be shifted to minimize the charging cost under dynamic time-of-use (TOU) tariff, where the high price time slots are penalized. In this manner, the proposed flexible coordination scheme improves service satisfaction as well as charging cost benefit even under the limited charging resources. For evaluation of the charging schemes, the entry-and-exit records of an office building parking lot are investigated assuming a certain percentage of the PEVs penetration with a TOU tariff. Since vehicles' arrivals are concentrated in the morning while their departures are distributed over the day, the proposed flexible charging coordination improves charging request execution rate, relative to uncoordinated charging approach such as first come first serve (FCFS). Also, overall charging cost can be further saved by jointly considering the TOU with USCD.