Mobile charging stations for EV charging management in urban areas: A case study in Chattanooga

The advancement of fixed charging stations (FCS) has facilitated electric vehicle (EV) charging and increased EV adoption. FCSs are especially important in dense urban areas, where home charging is not an option. However, FCSs' construction is limited by budget, fragile power grid infrastructure, and site constraints, among others. Therefore, suitable locations for building FCSs are limited. Even in the presence of FCSs, EV drivers face challenges such as long charging times and inconvenient charging locations. Mobile charging stations (MCS), which allow for scheduling and convenient charging, can be a supplementary charging technology to address these shortcomings and allow rapid expansion of charging infrastructure, assuming the MCS can be scheduled efficiently. This paper develops an optimization framework for the optimal charging management of EVs considering a multi-charger system integrating different types of FCSs and MCSs. Considering the EV driver's travel trajectory and time value, the proposed framework finds the optimal charging technology and location to minimize the EV user's overall charging cost and time. The model is implemented in Chattanooga, TN, USA, where the evaluation results demonstrated that MCSs are the optimal charging method for many EV users. Moreover, the results indicated that MCS mitigates the power grid stress caused by EV charging during peak hours.