A hierarchical dispatch model for optimizing real‐time charging and discharging strategy of electric vehicles

Abstract

Aiming at the problems related to the dispatch, decomposition, and coordination, temporal and spatial distribution, and the randomness of electric vehicles (EVs), this paper establishes a hierarchical dispatch model between EVs and the power grid to achieve energy conservation and economy optimization. The model is composed of two layers. In the upper layer, considering spatial and temporal distribution characteristics, a bi‐level economic dispatch model based on traditional unit commitment for EV aggregators is established. Then, on the account of the priority considering the convenience of EV users, the lower layer proposes the charging and discharging scheduling model for aggregators. In this layer, an evaluation index system is established by analyzing the impact of EVs' declared information, which includes the declared capacity and charging duration of EVs, the sincerity degree, and the battery loss, to determine the priority of scheduling for each EV based on the entropy method. Finally, the simulation is carried out on a four‐bus micro‐grid system. It shows that the hierarchical dispatch model could not only obtain the dispatch plan for aggregators but also divide the strategy results of regional power grid to each EV, to determine the optimal scheduling plan for charging and discharging of the EV aggregator in each period. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.