An integer clustering approach for modeling large-scale EV fleets with guaranteed performance
Abstract
Large-scale integration of electric vehicles (EVs) leads to a tighter integration between transportation and electric energy systems. In this paper, we develop a novel integer-clustering approach to model a large number of EVs by managing vehicle charging and energy at the fleet level yet maintaining individual trip dispatch. The model is then used to develop a spatially and temporally-resolved decision-making tool for optimally planning and operating EV fleets and charging infrastructure. The tool comprises a two-stage framework where a tractable disaggregation step follows the integer-clustering problem to recover an individual solution. Mathematical relationships between the integer clustering, disaggregation, and individual formulations are analyzed. We establish theoretical lower and upper bounds on the true individual formulation which underpins a guaranteed performance of the proposed method. The optimality accuracy and computational efficiency of the integer-clustering formulation are also numerically validated on a real-world case study of Boston’s public transit network under extensive test instances. Substantial speedups with minimal loss in solution quality are demonstrated.
Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Acknowledgments This work is jointly supported by the MIT Energy Initiative (MITEI) and Ralph O’Connor Sustainable Energy Institute (ROSEI) at Johns Hopkins University .