Study On Optimal Control Of Urban Three Level Micro Traffic Flow Considering Emissions

At present,the demand of urban transportation is increasingly intensified with the continuous growth of the economy.The most immediate impact is the damage of vehicle emissions for the global ecological environment.As one of the main sources of air pollution,vehicle exhaust has been paid great attention by scholars from every field The resources of urban road can not meet the growing demands of vehicles and thus reduce the travel efficiency of people.On top of that,the traffic congestion will further aggravate the emission of vehicle exhaust.Therefore,it is of great significance for improving the condition of urban roads to find an effective control strategy to optimize urban traffic lights systemThe goal of urban traffic management and control is the timing scheme of signal lights at the intersection of arterial roads.The adjacent signal lights will affect each other so that different timing strategies have different optimization results for the overall road condition.The unreasonable timing scheme of signal lights will lead to unexpected frequent changes in the running conditions of vehicles.The idling,acceleration,deceleration and parking behaviors of vehicles will increase the fuel consumption of vehicles and result in higher exhaust emissions.Hence,this paper considers urban traffic emissions as the optimal control target,and establishes the "point,line and area" urban three-level micro-optimal control strategy for traffic flowFirst of all,based on the VSP-based urban micro-traffic flow emission model and the improved micro-traffic flow model,the urban single-point intersection traffic emission optimization model is established.Then,the simulated annealing algorithm and classical genetic algorithm are discussed,and the optimal control strategy of urban single point traffic flow considering emissions is established basing on simulated annealing algorithm and classical genetic algorithm respectively.Secondly,this paper analyzes and discusses the shortcomings of the classical genetic algorithm and the optimization strategy commonly used at present.An improved annealing genetic algorithm(ISAGA)is presented,which inserts the numerical simulation process of urban traffic flow into the calculation process of fitness function.Then the improved genetic operator for urban traffic flow are designed.The traffic emission optimization model of urban arterial roads is built,and based on the ISAGA,the optimal control strategy of the micro traffic flow considering the emission is established.Finally,this paper realizes the docking between VISSIM platform and C++control platform in VS environment,and studies the secondary development process of VISSIM based on COM interface programming.The traffic emission optimization model of urban road network is built,and traffic simulation data of VISSIM urban road network is extracted through COM interface,so as to realize the timing optimization control strategy for urban road network.And through a series of experimental result,the effectiveness of improved annealing genetic algorithm in semaphore optimization control is studied.In conclusion,considering the urban traffic emission as the control target,this paper analyzes the research on the optimal control of signal lights within the scope of single point intersection and urban arterial road,and discusses the optimal control strategy of urban road network level through COM interface programming,extending from the field of "line control" to "face control",which is the basic source of follow-up research theoretically.