Multi-Objective Electric Vehicle Charge Scheduling Using Two-Way Chargers with Optimal Time of Use Tariff

Abstract

With the rapid uptake of the Electric Vehicle (EV) fleet in transportation services in recent years, the power grid faces critical challenges in meeting the extra power demand. EV charge scheduling is a multi-objective optimization problem in nature, and it requires optimizing several conflicting objective functions, such as the impact on the local grid and the benefit of EV Charging Station (EVCS) operators and EV owners. This manuscript proposes a multi-objective optimization framework considering the optimal time of use (TOU) tariff in EVCSs. We integrate dynamic economic dispatch with TOU tariffs to obtain optimal market electricity prices, modify electricity consumption patterns, and minimize the load variance to flatten the load curve. Our results show that the proposed framework can effectively modify the load profile, obtain optimal electricity prices, and make a trade-off between the conflicting objectives. The proposed methodology effectively addresses the load profile valley-filling problem and the occurrence of rebound peak by applying dynamic electricity pricing mechanisms. By incorporating this mechanism into the dynamic economic dispatch problem, we find that further benefits can be delivered to EV owners, the local grid, and EVCS owners.

Keywords: electric vehicles, Multi-objective optimization, two-way charging strategy, time of use tariff, electric vehicle charging stations