Multi-objective Optimization Model Of Intersection Signal Control Considering Vehicle Emission Characteristics

With the rapid growth of motor vehicle ownership and traffic volume, traffic congestion, traffic accident, and air pollution become more and more serious in recent years. The congestion of network often starts from congestion of intersections, which leads to the increase of traffic delays, decrease of vehicle speed, and increase of time loss and fuel consumption. Thus, the urban environment and air quality become worse by the increase of the traffic emission. Combining with the National Basic Research Program of China "Traffic Flow Coordinated Control Theory and Method for Multi-modal Network", the research on multi-objective optimization model of intersection signal control considering vehicle emission characteristics was conducted in this paper.First, the emission characteristics of light duty and heavy duty vehicles were analyzed based on the classification of vehicle operating modes at intersection and a large number of measured vehicle operation data and the corresponding emissions data. In this paper, vehicle operating modes were classified into idle, acceleration, deceleration, and cruise. The average emission rates of different emissions for light duty and heavy duty vehicles in each operating mode at intersections were calculated.Secondly, vehicle operation rule at intersections was described. Based on the mathematical derivation method, the running time and distance of vehicles in different driving modes can be calculated. Thus, a time distribution model for each operating mode at intersections was proposed. Based on the existing delay model and stop ratio model, the parameters of the proposed time distribution model were calibrated. Then, a measured method for emissions at intersections based on the average emission rates and time distribution for each operating mode was proposed.On the basis of the study, a multi-objective optimization model of intersection signal control considering the emissions, traffic delays and stops of vehicles was proposed. Each optimal objective was processed by dimensionless normalization method. With the MATLAB programming tool, a solving method based on weighted optimization and genetic algorithm (GA) was designed for the model.Finally, a case study at a typical intersection was conducted for the application analysis of the proposed model in this paper. What’s more, the optimization results of the proposed model and HCM2010were compared. The results show that the optimal results by the multi-objective optimization model of intersection signal control proposed in this paper were better than the HCM2010method’s. Thus, the proposed model in this paper can effectively reduce the intersection traffic emissions and traffic delays, and improve the efficiency of the intersection traffic.