Research On Authentication And Authorization Mechanism Of Electric Vehicle Dynamic Charging

With the depletion of fossil energy and the increasingly serious environmental problems,all countries around the world are vigorously promoting the development of electric vehicles.Dynamic wireless charging technology,as an important interactive way between electric vehicles and smart grids in Vehicle to Grid(V2G)networks,charges the on-board battery when the vehicle is driving at high speed.However,when electric vehicles join the dynamic wireless charging system,how to effectively manage and control vehicle users to access wireless charging services,protect the proprietary information of charging vehicles and meet the different charging needs of vehicle users are facing great challenges.This thesis focuses on the security and privacy requirements of electric vehicle dynamic wireless charging systems,and designs authentication and authorization schemes to achieve privacy preservation.Firstly,in order to meet the security and privacy requirements of electric vehicle charging process in the dynamic wireless charging system,the thesis proposes an offline privacy preservation authentication authorization scheme.This solution has the following advantages:(1)Offline authentication and authorization: When the power center is offline,the authorized electric vehicle can normally access the charging service.(2)Conditional privacy preservation: In the process of electric vehicles accessing charging services,the identity privacy and location privacy of electric vehicles are protected.Only in the event of bad behavior or dispute,the identity information of the vehicle user will be revealed by the power center.Secondly,in order to solve the above-mentioned solutions that cannot meet the different charging needs of vehicle users and revoke user rights,the thesis proposes a fine-grained charging service authentication and authorization scheme.This solution has the following advantages:(1)Efficient user rights management: The power center uses an encryption method based on geographic location attributes and time attributes to issue time-sensitive authorization tickets for electric vehicles.Once the authorization ticket expires,the vehicle will not be able to access the corresponding charging service.(2)Privacy preservation: When the electric vehicle accesses the charging service,the roadside unit determines the access right of the vehicle user through an authorization ticket.The authorization ticket does not involve the identity of the vehicle user,thereby achieving the privacy preservation of the vehicle user.(3)Hierarchical management: According to the hierarchical system structure of the dynamic wireless charging system,hierarchical management of the geographical location attributes of the entities in the system,the higher-level institutions can generate authentication keys for the lower-level institutions or infrastructure,which greatly reduces the computational strength of the power center.In addition,the time attribute tree is used to hierarchically manage the time attribute,which reduces the difficulty of managing the time key.(3)Hierarchical management: According to the hierarchical system structure of the dynamic wireless charging system,hierarchical management of the geographical location attributes of the entities in the system,the higher-level power branch can generate authentication keys for lower-level power branch or roadside units,which greatly reduces the power center calculation strength.In addition,the time attribute tree is used to hierarchically manage the time attribute,which reduces the difficulty of managing the time key.Finally,the thesis not only proves the security of the above two schemes,but also indicates that the scheme has certain application value in the dynamic wireless charging system of electric vehicle through performance analysis.