降低交通排放的干线协调信号控制优化方法

为降低干线道路系统的交通排放量,基于机动车比功率改进红绿灯期间排放因子的标定方法,进而以相位有效绿灯时间为决策变量,构建使机动车排放总量最小化的干线交叉口群时空资源优化模型.分析相邻交叉口间车队延误与相位差的关系,改进以车队延误最小为目标的相位差优化模型.为验证模型,设计一个案例,根据传统方法获得参考配时方案,借助Vissim软件标定红绿灯期间的排放因子,并使用所提方法获得优化配时方案.结果显示,每种污染物绿灯期间的排放因子均明显高于红灯期间;与参考配时方案相比,优化配时方案下各交叉口车辆延误和排放量均减少8~11%.所提模型能同时降低干线交叉口群的车辆延误和交通排放量,可用于优化干线协调信号控制方案,进而缓解交通拥堵. 

An Optimized Method for Reducing Traffic Emissions in Arterial Road Using Coordinated Signal Control

To reduce traffic emissions in an arterial road system, an improved calibration method on the basis of specific power of vehicle is proposed to compute the emission factors during the period of traffic light.An optimization model for allocation of spatial-temporal resources is developed for one arterial intersection group.The decision variable is the effective green time in each phase, and the objective function is to minimize the total emissions for all intersections.By analyzing the relationship between the delay for one platoon and the phase difference between adjacent intersections, this optimized model aiming at minimizing the delay for one platoon, is amended.A case study is carried out to verify this model.A control scheme for traffic signals is firstly obtained as a reference by using traditional methods.The emission factors during the period of traffic light are calibrated by Vissim software.A control scheme for traffic signals is optimized by this proposed method.The results indicate that the emission factors of each pollutant during a green phase are explicitly greater than which during a red phase.Compared with referenced control schemes for traffic signals, both delay of vehicles and traffic emissions decrease by 8-11% at each intersection when the optimized control scheme is adopted.It shows that this proposed model can be applied to decrease both the delay of vehicles and traffic emissions in an arterial road system.Thus, it can generate a coordinated control scheme for traffic signals, and relieve traffic jam.