Bi-level Optimization for Dispatching Grid-Interactive Electric Vehicles in an Urban Community

This paper presents a bi-level optimization model aimed at enhancing the operational efficiency and economic viability of electric vehicles (EVs) interacting with urban community power grids. The proposed model particularly examines the intricate relationships among EV charging and discharging characteristics, urban transmission systems, and distribution networks. The upper-level optimization model focuses on the overall integrity and economic efficiency of the urban power grid, with the objective of minimizing operational costs, which include the start-up and generation costs of thermal power units, environmental costs, penalties for wind and PV generation reductions, as well as the charging costs incurred by EV users. Conversely, the lower-level optimization model determines the optimal charging and discharging locations for EVs through optimal power flow (OPF) calculations to enhance the resilience of the distribution network. Through case studies, this paper validates the effectiveness of the proposed model and demonstrates the impact of varying electricity pricing structures on upper-level optimization. The findings reveal that the bi-level optimization model can adeptly manage EV charging and discharging, fostering a mutually beneficial scenario among the urban grid, charging network operators, and EV owners.