Research On Cooperative Control Optimization Of Urban Expressway Toll Stations And Connecting Sections

In our country’s urban areas,expressway toll stations are an important node connecting expressways and urban roads.Affected by many aspects such as the level of traffic and the spatial structure of toll stations,the traffic flow during peak hours will put greater pressure on the toll stations,and traffic congestion is prone to cause traffic bottlenecks.With the popularity of ETC(Electronic Toll Collection)lanes in my country and the increase in the proportion of ETC vehicles,the capacity of toll stations has been greatly improved.Therefore,when general urban road sections,intersections or upstream expressway ramps and main lines connected at the exit of the toll station are congested How to use the traffic capacity of toll stations reasonably and tap the function of toll stations to regulate traffic flow to achieve the purpose of optimizing regional traffic flow and reducing traffic congestion is an important research content of expressway system control under the new situation.In this paper,by tapping the function of toll stations to regulate traffic flow,the collaborative optimization control of expressway toll stations in urban areas,downstream urban roads,and upstream expressway main lines are respectively studied.The main research contents are as follows:First,it introduces the common types of expressway congestion and the corresponding optimization methods,analyzes the root causes of congestion in principle,and analyzes common traffic flow optimization parameter indicators,which are used as the basis for evaluating the degree of traffic improvement.Second,for the coordinated control of toll station exits and connecting urban roads and intersections,with the goal of optimizing the system’s queue length,delays,and average number of stops,a strategy for regulating the capacity of toll stations is proposed,and the coordination of toll stations and connecting intersections is introduced.Control method,establish a cooperative control model.A case simulation of the model shows that the model can significantly improve the traffic flow of the system.Third,in order to control the inflow of expressway toll stations,a toll station entrance lane adjustment algorithm based on demand-capacity difference control is proposed.The total travel time is used as the evaluation index of the operation efficiency of the road network,and the demand-capacity difference is evaluated.The optimal ramp regulation rate and the number of lanes in the toll station under the constraints are calculated,and the effect of the algorithm in reducing the total travel time of the road network is verified through the dynamic traffic flow.The simulation case reflects the rationality and effectiveness of the algorithm,and has good robustness when the traffic volume of the road network fluctuates.Fourth,for the coordinated control of the entrance to the toll station and the main line of the connecting expressway,combined with the variable speed limit control theory of the expressway main line,a model of the toll station channel adjustment and the variable speed limit coordinated optimization control model is established,and the toll at the dynamic time is decided The number of open lanes of the station and the speed limit of the main line realize the optimal traffic flow state of the system.Finally,the feasibility and superiority of the collaborative control model are verified by the simulation analysis of the actual road network.