Optimal EV Charging Scheduling by Considering the Limited Number of Chargers

Lack of charging facilities is still a significant barrier to the electrification of the logistic system. How to effectively schedule the electric vehicle (EV) charging power to reduce the charging station operating cost when the number of chargers was limited becomes an important issue. To tackle this issue, an optimal charging scheduling method by responding to the time-of-used (TOU) electricity price is proposed. First, the uncontrolled charging model to fully charge EVs as fast as possible is established. Then, an optimal charging scheduling model by considering the limited number of chargers is proposed to both reduce the charging cost and guarantee the charging demand of each EVs. The proposed model is formulated as a bilevel programming (BP) model. The charger index and available charging duration for each EV are determined at the upper level, while the charging power of each EV at each time slot is determined at the lower level. After that, a solving approach is introduced for the proposed BP model. The efficacy and performance of the proposed charging scheduling method are verified by simulation results.