Comfort violation minimization oriented energy management strategy for a renewable-assisted stand-alone multi-energy electric vehicle service station

Abstract

In this study, a comfort violation minimization oriented energy management strategy is proposed for a stand-alone electric vehicle (EV) service station serving multiple EV types in a multi-energy manner. The main purpose of this strategy is to minimize the discomfort of EV owners due to insufficient energy supply while considering the fairness among users and optimizing the utilization of renewable energy sources. The criteria for selecting this strategy include: (1) mitigating customer dissatisfaction arising from inadequate energy supply, (2) ensuring fairness in energy distribution among different EV types, and (3) maximizing the use of renewable power sources, such as photovoltaic (PV) units. The developed mixed-integer linear programming (MILP) model comprises a PV unit as the main power source, with an energy storage system (ESS) and an electrolyzer-supported main hydrogen storage unit fulfilling the energy and hydrogen demands of battery electric vehicles (BEVs) and fuel cell electric vehicles (FCEVs), respectively. A comfort violation fairness constraint is also introduced to guarantee a fair service for all EV owners, thereby enhancing the social acceptability of the provided EV service.Simulation results, obtained under various case studies considering component size changes and comfort fairness constraint relaxation, demonstrate the importance of striking a balance between investing in larger components and allowing for a certain level of customer dissatisfaction. The analysis revealed that relaxation of the fairness constraint led to a reduction in overall comfort violation by up to 15 % for both BEVs and FCEVs combined; however, this relaxation resulted in significant differences in comfort violation among different EV owner types, with variations ranging from a minimum of 0 % to a maximum of >90 %. These findings emphasize the significance of considering fairness in energy distribution to prevent potential dissatisfaction among end-users. Future studies will explore the development of a grid-connected system and compare the stand-alone structure in a techno-economic context, considering the possible impact of different EV types on grid operation during normal and resiliency-oriented conditions.