A decentralized optimization method to track electric vehicle aggregator´s optimal charging plan

Many papers focus on electric vehicle (EV) aggregators´ participating in the operation of transmission grid, but the practical interaction of EVs and power grid is implemented through charging every single EV. Therefore, it´s necessary to make hundreds or thousands of EVs optimally charge to track an aggregator´s optimal charging plan assigned by the power grid. In this paper, this tracking problem is formulated firstly and then a decentralized optimization method is proposed to solve this problem of which the size is usually too large to solve efficiently in a centralized way. The optimality of the method is proved under certain conditions. Case study for a simple scenario and numerical tests with various EV numbers show that the proposed method is not only optimal but also scalable.