En-route fast charging infrastructure planning and scheduling for battery electric bus systems

The recent advancements toward fast charging technology enable electric buses to be re-charged at bus stops during passengers' boarding and alighting times. The costs of en-route charging can be substantially reduced through facility sharing among buses from multiple lines, which may, however, result in charging conflicts. This study investigates the charging infrastructure planning and scheduling for a battery electric bus (BEB) system, considering en-route charging and charging conflict avoidance. We introduced a station-based discrete-event approach to discretize the BEB operation system for an entire day. Subsequently, two models were established to determine the charging scheduling and infrastructure planning, which are further reformulated as linear mixed-integer programs. Dwelling times with- and without potential charging conflicts were distinguished in advance and processed separately to reduce the scale of the problem. Numerical examples demonstrated that the proposed models could be solved efficiently in a large BEB system, and cost-effective en-route charging is achievable.