  Electric vehicles (EVs) can be considered as flexible mobile battery storages
in microgrids. For multiple microgrids in an area, coordinated scheduling on
charging and discharging are required to avoid power exchange spikes between
the multimicrogrid system and the main grid. In this paper, a two-stage
integrated energy exchange scheduling strategy for multimicrogrid system is
presented, which considers EVs as storage devices. Then several dual variables,
which are representative of the marginal cost of proper constraints, are
utilized to form an updated price, thereby being a modification on the original
electricity price. With this updated price signal, a price-based decentralized
scheduling strategy is presented for the Microgrid Central Controller (MGCC).
Simulation results show that the two-stage scheduling strategy reduces the
electricity cost and avoids frequent transitions between battery
charging/discharging states. With the proposed decentralized scheduling
strategy, each microgrid only needs to solve its local problem and limits the
total power exchange within the safe range.
