Design Optimization of Microgrid Incorporating Battery Exchange-based Electric Vehicles

The microgrid is among the most feasible considerations for practical large-scale implementation of distributed renewable energy sources (DERs) into the existing grid system. Due to the problem of intermittency associated with DERs within the microgrid, design tasks usually involve the effective integration of energy storage systems (ESS) and electric vehicles (EVs). This increases the number of operating entities and operational conditions available within the microgrid, thus the optimal design of the microgrid happens to be challenging. In this paper, an optimization framework of DER sources-based standalone microgrid with battery exchange (BE) based EVs is proposed to determine the optimal number of DERs and size of central BE station for maximum utilization of DERs and minimization of the Levelized Cost of Energy (LCOE). The minimization problem involves a set of operational constraints such as conditional restriction of the annual total loss of the power supply and a proposed EV user dissatisfaction index. To account for BE station battery degradation, the minimal BE-station capacity is included as an optimization variable and the replacement cost function is integrated with the optimization cost function.