Research On Signal Optimization Control Based On The Control Logic Of Overlapping Phase Of The Traffic Flow

The traffic flow of urban intersection of our country,which is unbalanced,random and complicated,Research of the traffic signal optimization control technique which is based on the characteristics of traffic flow in the intersection of China is the key to improve the efficiency of the urban intersection.This paper analyzes the phase combination of traffic flow in the intersection of Chinese cities,and studies the optimization algorithm of the overlapping phase of the traffic flow,with which as the technical main line,carries out the research of dynamic optimization control algorithm of single intersection,bidirectional coordinated optimization control algorithm of the trunk and bus signal priority control algorithm and model of the trunk.The algorithm and model are verified by application of practical intersections.The research work of this paper mainly includes the following aspects:1.In order to solve the problem of green time loss caused by the unbalanced distribution of traffic flow in the conventional symmetric phase of the intersection,the overlapping phase optimization algorithm of the traffic flow is studied.The overlapping phase optimization design algorithm and the calculation method of the key flow ratio of its embedded sub-phase are proposed.The algorithm chooses the traffic flow phase group with the minimum cycle flow ratio as the optimal phase combination,and sets up the objective optimization function with the optimization objective of the minimum total delay of vehicles of the intersection,using the particle swarm optimization algorithm to optimize the green time of the optimal phase group.A numerical example is presented to verify the algorithm.2.According to the strong randomness characteristics of the traffic flow and the signal control with poor flexibility in China,the dynamic optimization control algorithm based on overlapping phase of single intersection is studied.By calculating the queue delay of the traffic flow to construct the intersection benefit function,this algorithm selects the traffic flow of the main and secondary phase which with the minimum queue delay to realize the overlapping phase dynamic optimization.Based on this,the objective optimization function is set up with the minimum queue delay as the optimization objective,and the particle swarm algorithm is used to optimize the green time of the overlapping phase.The application verification for the dynamic optimization control of the single intersection is carried out.3.According to the high complexity and poor applicability of existing research in bidirectional coordinated optimization algorithm of the trunk,the bidirectional coordinated optimization control algorithm of the trunk is studied.Using optimization control logic of the coordinated overlapping phase,the green wave time-distance diagram is constructed.By calculating the mapping relation of the signal cycle,design speed and distance between intersections,the algorithm for the offset,overlapping phase and signal timing is proposed.Through the analysis of the problem of signal mutation and migration during the implementation of the coordinated control scheme,the smooth conversion and automatic correction algorithm of the offset is studied.The application validation for bidirectional coordinated control of the trunk is carried out.4.According to the problem of poor flexibility and low efficiency during the implementation of the bus signal priority control of the coordinated signal of the trunk,the algorithm and model of bus priority control based on the overlapping phase of the coordinated signal of the trunk is studied.Through the study of the overlapping phase control logic of the bus signal priority and the method of determination of the priority,the multi-phase bus signal priority control algorithm based on overlapping phase control logic is established.By analyzing the total delays and fuel consumption targets of the intersection,the timing optimization model for bus signal priority control which takes consideration to the resource constraint is established.The application validation for bus signal priority control of the bidirectional coordinated signal of the trunk is carried out.