Research On Traffic Signal Intelligent Control Modeling And Optimization

With the rapid development of society and economy,the number of urban motor vehicles has increased rapidly and the problem of urban congestion has become increasingly serious.This has brought about a series of problems while restricting the urban economic development.Intersections,as the meeting point of urban roads,are the concentrated areas where traffic congestion is a problem.Urban traffic trunk is an important part of the urban road network,which can alleviate traffic congestion and improve the traffic efficiency of the road network through coordinated control of the traffic signal of the main line.Therefore,this article aims at the above two aspects of traffic signal control research.The main work of this dissertation is as follows:(1)Describes the research background and significance of this thesis,and analyzes and summarizes the development of traffic signal control.(2)Based on the analysis of the basic theory of traffic,aiming at the minimum total number of vehicles at intersections,a real-time optimization timing model of four-phase intersections is established.For fixed periodic sequences with fixed periods,fixed periodic sequences with uncertain periods and non-Fixed-phase sequence of three control strategies to design a genetic algorithm,and optimize the solution.In order to test the control effects of the above three different strategies,experiments were carried out on three different traffic conditions with low,medium and high traffic intensity respectively.The three control strategies were compared with the traditional timing control.From the simulation results,on the whole,the control effect of indefinite periodic fixed phase sequence control and indefinite periodic non-stationary phase sequence control is better than fixed periodic sequence control and timing control.(3)In view of the fact that the math model of trunk traffic signal coordination control ignores the influence of tributary traffic flow on trunk coordinated control,this thesis considers the influence of tributary traffic flow,and the control model of trunk signal is refined and improved.Taking the delay time of the main line as the target,the phase difference and the coordination green time as the control variables.(4)The trunk delay analysis is carried out separately from the optimization of phase and phase difference and coordinated green-light time joint optimization,and the genetic algorithm is used to optimize the solution.Experiments on different traffic intensity are carried out,and the two control strategies are compared with the traditional timing control.From the simulation results,the joint optimization of the control effect is better than the single optimization,the single optimization of the control effect is better than the timing control.In the meantime,this thesis also considers the unbalanced traffic intensity of the two-way trunk and the influence of the change of the distance between the intersections on the optimization results.