Stability Analysis Of Intelligent Connected Vehicle Platoon With Communication Delay

The intelligent network-connected vehicle platoon achieves cooperative and efficient operation with the desired spacing and speed through information interaction between vehicles,which can effectively improves traffic capacity and safety,and reduces fuel consumption and environmental pollution.However,vehicle-to-vehicle communication and vehicle-toinfrastructure communication are depressed by some factors such as bandwidth limitations and channel congestion,which inevitably bring communication delay,reduce the control performance of vehicle platoon,even cause system instability,and seriously affect driving safety.Therefore,this thesis studies the stability of the intelligent network-connected vehicle platoon with communication delay,proposes several novel types of Lyapunov functions,improves the effiency of stability analysis,obtains a more accurate upper bound of delay,and conducts real-time simulation verification.The main contents are summarized as follows:(1)Stability analysis of the intelligent network-connected vehicle platoon with constant communication delay is carried out.Firstly,according to the dynamics of the vehicle,the intelligent network-connected vehicle platoon model is established,and a distributed controller is designed based on consensus.Secondly,in order to give the time delay upper bound of the stability of the vehicle platoon efficiently,a Lyapunov-Razumikhin function is designed to obtain sufficient conditions for the stability of the vehicle platoon simply and efficiently.Furthermore,in order to obtain the exact upper bound for the stability of the vehicle platoon,a novel type of Lyapunov matrix function is proposed,and a discrete complete LyapunovKrasovskii functional is designed to give the necessary and sufficient conditions for the stability of the vehicle platoon.Finally,the effectiveness of these two algorithms for vehicle platoon stability analysis under constant time delay is verified by Matlab simulation.(2)Stability snalysis of the intelligent network-connected vehicle platoon with timevarying communication delay is studied.Firstly,considering the time-varying characteristics of communication delay,a distributed controller for the intelligent network-connected vehicle platoon is designed.Secondly,a Lyapunov-Krasovskii functional is constructed,and the criterion for the stability of the vehicle platoon with time-varying delay is given.Compared with the Lyapunov-Krasovskii functionals constructed in other literature,the upper bound of delay obtained by the proposed stability analysis algorithm is less conservative.Finally,the validity of the stability analysis criteria and corresponding algorithm for the vehicle platoon under the proposed time-varying delay is verified by Matlab simulation.(3)Based on the PLEXE platform,a real-time simulation verification of the intelligent network-connected vehicle platoon is performed.Firstly,the PLEXE simulation platform is redeveloped to build a ‘three elements’ framework for vehicle platoon control.Firstly,the vehicle dynamics model,communication topology and controller are built into PLEXE’s SUMO to implement a realistic simulation of the intelligent network-connected vehicle platoon.Secondly,based on the conditions of the research content(1),a real-time simulation of PLEXE with constant time delay is performed.The simulation results are in agreement with the theoretical derivation and numerical simulation results.Finally,based on the conditions of the research content(2),a real-time PLEXE simulation with time-varying delay is performed to verify the feasibility and applicability of the proposed stability criterion and control algorithm.