Charging Strategy of Electric Vehicles Considering Three-phase Unbalance Mitigation of Distribution Network With New Energy

Aiming at the three-phase unbalance problem caused by the large-scale integration of electric vehicles and new energy into the grid, a charging strategy for electric vehicles considering the three-phase unbalance mitigation in the medium voltage distribution network is proposed. Firstly, the electric vehicle aggregator model and multiphase distribution network model are established respectively; Secondly, a three-phase balance incentive mechanism is proposed to encourage electric vehicles to spontaneously help improve three-phase voltage unbalance; Then, with the goal of maximizing the benefits of electric vehicles, considering the constraints of electric vehicle charging and distribution network safety, a deterministic optimization model for electric vehicle charging is established; Furthermore, the uncertainty of new energy output is studied based on robust optimization theory, and a robust optimization model for electric vehicle charging is established; Finally, simulation verification is conducted using the adapted IEEE 13-node distribution network. The results show that the proposed charging strategy can effectively reduce the three-phase voltage unbalance in the distribution network and the cost of electric vehicle users, and ensure the safe operation of the distribution network when the output of new energy is uncertain. © 2024 Power System Technology Press. All rights reserved.