Study On The Method Of Optimizing The Speed Of Eco-driving At The Continuous Intersections Based On Vehicle Networking

The factors that affect the fuel economy of vehicles driving on urban roads include not only the state of the vehicle itself,but also the road traffic conditions,the driver behavior and so on.When there is a continuous intersection at the road,because the vehicle can't predict the traffic lights information and the road traffic information at the intersection,it often occurs emergency deceleration,rapid acceleration,unreasonable shifting and wait for a long time when the light is red,resulting in poor fuel economy and reduced access efficiency.In order to improve the fuel economy of vehicles driving on urban roads,this paper studies the optimization method of the speed of Eco-Driving based on communication on vehicle-to-infrastructure(V2I).Through the traffic information,road information,SPaT(Signal Phase and Timing)and so on,obtained from the internet of vehicles,the speed-reporting system with energy saving effect can be set up,which can provide the reasonable speed for the driver and avoid the phenomenon of fuel consumption caused by the driver's habit of driving and the lack of traffic information.In order to explore the driving regular of the vehic le that experiences continuous intersections on the actual road,the driving experiment of six periods was carried out in a section of Shanghai.By collecting the speed and latitude and longitude data,the traffic speed characteristics of vehicles are analyzed and according to the driving characteristics of each stage,the speed of vehicles at different time periods is optimized and formulated in different sections during the passage of the intersection.A speed optimization unit consisting of a fixed speed section,an adjustment section in the upstream phase,and a recovery section in the downstream phase is established.It is found that the phase time of the red light has a significant influence on the speed trajectory,therefore,based on the assumption of the remaining time of the red light,when arriving at the crossing intersection,an optimization model of the Speed of Eco-Driving based on the vehicle speed optimization unit is formulated.Under the premise of ensuring traffic efficiency,the minimum value of fuel consumption of the vehicle on the entire journey is used as an optimization function to solve the three speed sections in the vehicle speed optimization unit to obtain the speed curve with the minimum fuel consumption,and in order to ensure the smoothness of driving,a trigonometric function is used to optimize the speed at the connection of two speed values.By comparing the fuel consumption of the three driving schemes for the remaining time of each red light,the most fuel-efficient speed planning proposal is obtained.In this paper,the relationship between driving speed,engine power,driving force and fuel consumption under six operating conditions is used to fit out a three-order fuel consumption model based on power.Through this insta ntaneous fuel consumption model,the fuel consumption of the entire trip is calculated.