A Novel Multi-Level Charging Strategy for Electric Vehicles to Enhance Customer Charging Experience and Station Utilization

Currently electric vehicle (EV) charging stations are equipped with chargers having fixed charging rates where the users do not have control over their charging schedule, except to decide whether they require a full recharge or partial recharge. In addition, no matter what kind of charging technique is adopted, EV charging takes much time compared to refueling conventional vehicles. This lengthy time at a charging station is the reason why people are hesitant to switch to EVs from internal combustion engine vehicles. The long waiting time may lead to congestion at the charging stations. This has motivated us to develop an efficient multi-level charging system (MlCS) that allows EV customers to specify their charging needs and provide them with charging at the best charging rate possible. The proposed MlCS put forward here features multiple charging levels on a single charger and each level corresponds to a distinct charging rate. Taking the interest of customers into account, the selection of charging rate for the customer is based on his priority for battery lifetime and recharging time. Further, the MlCS is integrated into the station planning problem to analyze the effect of MlCS on station capacity estimation and their impact on the power grid. Finally, the numerical results illustrate that MlCS is better for improving the customer quality of service. The contribution of the proposed model allows decision-makers and operators to develop charging stations with multi-level chargers and provide a better service for customers with different charging options.