Research On Coordinated Control Of Stability And Energy Consumption Of Heterogeneous Vehicle Platoon

Intelligent Connected Vehicle(ICV)integrates the characteristics of intelligent vehicles and connected vehicles,and is an important and vital part of intelligent transportation system.ICV is considered an important solution to the increasingly serious traffic problems such as road congestion and energy consumption,and vehicle platoons,as an important application,have great potential to realize multi-vehicle cooperative control,environmental awareness,improve road traffic efficiency,reduce energy consumption and traffic accidents.However,the popularity of ICV is expected to be a gradual process,and ICV will coexist with human-driven vehicles(HV)on the road for a long time in the future,so research on the heterogeneous vehicle platoon is an urgent need.String stability control is a prerequisite for effective platoon control by ensuring that the platoon travels at the desired speed and configuration.Most of the studies on heterogeneous platoon stability and energy saving have only focused on one aspect,without considering the string stability under other factors of the vehicle platoon.Therefore,in this paper,a comprehensive consideration of heterogeneous platoon string stability and eco-driving is conducted to ensure that the platoon travels at its optimal energy consumption speed while taking into account the stability of the platoon,and the main research work and innovation points are as follows.(1)A study on the string stability of a heterogeneous vehicle platoon with multiple time lags is carried out.In this paper,the Intelligent Driver Model(IDM)is used to describe the vehicle tracking characteristics.The IDM is extended to a multitime lag IDM model by considering the time lag characteristics of the heterogeneous vehicles,and the stability criterion of the multi-time lag heterogeneous platoon is derived by mathematical derivation.The stability mechanism of the heterogeneous platoon is also investigated by analyzing the market penetration rates(MPR),headway time distance and other parameters of different vehicles.(2)An ecological driving control model for achieving heterogeneous vehicle platoon stability is proposed,and the energy-optimal speed profile satisfying vehicle platoon stability is calculated using an optimization algorithm.Firstly,the instantaneous power model of electric vehicles is established by considering the vehicle air resistance changes in the platoon due to the workshop distance and the vehicle kinetic energy recovery.Secondly,the original energy optimization model is reconstructed and combined with the heterogeneous platoon stability to construct an easy-to-solve nonlinear optimization model,reducing the decision variables and taking the string stability as the constraint.The stable ecological driving of the heterogeneous platoon is realized,so that heterogeneous vehicle platoon control solves the problem of striking a balance between stability and energy saving.The model is validated through numerical simulations of urban multi-signal intersection scenarios,and the sensitivity of the relevant parameters is analyzed to investigate the intrinsic characteristics of the model.(3)A traffic flow benefit analysis framework is developed and analyzed for heterogeneous traffic flows.Firstly,the heterogeneous traffic flow benefit analysis framework is established based on the proposed stable ecological driving control model,and the basic traffic flow diagram,maximum service flow rate and conversion coefficient of heterogeneous vehicles are analyzed based on the stable ecological driving control,and the calculation formulae of density and capacity of heterogeneous traffic flow are obtained.The basic flow-density diagrams,speed-density relationship diagrams under different headway time spacing and MPR,as well as the basic analysis under steady speed reveal the influence of relevant parameters on traffic flow.The analysis is also carried out for the maximum service flow rate of each class under different MPR,vehicle conversion factors under different headway time spacing and MPR to reveal the influence of different MPR and headway time spacing on the mixed traffic flow.