Secure and Semi-Decentralized Blockchain-Based Privacy-Preserving Networking Strategy for Dynamic Wireless Charging of EVs

Dynamic wireless charging (DWC) facilitates energy transfer from the electric grid to moving electric vehicles (EVs) via charging pads (CPs) positioned along roadways. To maximize satisfied charging requests, given the limited supply capacity, dynamic charging coordination is required to determine suitable CPs for mobile EVs. Charging coordination necessitates EV owners to share their information (i.e., the identities and locations) with charging service providers (CSPs) to allocate the best CP for charging. However, charging coordination raises privacy concerns due to the exchange of private information. Moreover, a fast authentication mechanism is then required between EVs and CPs to initiate the charging process. In addition to the privacy limitation, existing DWC strategies lack the presence of multiple CSPs, which is a crucial aspect given the significant growth of the EV market. Consequently, centralization arises, with a single CSP overseeing the entire network. This paper proposes a semi-decentralized privacy-preserving networking strategy utilizing a specially designed consortium blockchain to support dynamic charging coordination, authentication, and billing while ensuring user anonymity and data unlinkability. Our proposed strategy leverages a novel semi-decentralized K-times group signature scheme and distributed random number generators to achieve privacy and decentralization. Simulation results showed that the proposed method reduces the EV authentication time to 0.1 ms while limiting storage requirements to just 4 MB per block at each EV. Additionally, the proposed strategy showed improved security and privacy features when compared with IBM’s privacy-preserving blockchain (Identity Mixer).