ExPO: Exponential-based Privacy Preserving Online Auction for Electric Vehicles Demand Response in Microgrids

In this paper, we address the problem of demand response in microgrids (MGs) through scheduling Electric Vehicles (EVs) charging at swap stations. Swap station has attracted growing attentions due to properties of fast charging and peak load shifting. Thus how to schedule EV charging reasonable at swap station requires careful designing. A reasonable charging policy should i) ensure batteries in swap station to be allocated to EV who really value them, ii) protect the EV owners private information, i.e. valuations from being inferred by the adversary. To tackle these issues, we present an Exponential-based Privacy Preserving Online Auction scheme (ExPO), which enables energy trading among EVs and batteries in swap stations. Particularly, EVs and batteries act as buyers and sellers, respectively, while the auctioneer is responsible for maximizing the market social welfare by matching buyers and sellers. In our research, we conduct a theoretical analysis and demonstrate that our online auction scheme achieves the properties of individual rationality, incentive compatibility and E-differential privacy. The result of extensive performance evaluation shows that the proposed auction scheme not only achieves good performance with respect to social welfare, privacy leakage, but also can help the power system shift peak load.