城市交通过饱和状态下干线信号的多目标仿真优化研究

针对城市交通过饱和状态下的干线信号优化问题,分析了交通控制目标对车辆排队的影响,提出以绿信比、相序、相位差和周期为优化参数,以车辆平均时延、系统平均排队-车道长度比和系统通行能力为优化目标的交通信号仿真优化模型。构建了优化模型的实施框架,该框架采用自主构建的微观交通仿真环境来获取信号方案评价指标,改进多目标优化算法NSGAII中的重复个体问题,完成对干线各交叉口信号配时方案的同时优化。最后,利用采集的交通数据对由3个交叉口组成的干线进行实例验证,验证结果表明,在过饱和状态下,所提出的信号优化方法不仅可以有效控制车辆排队长度,均衡车辆分布,同时在系统通行能力、车均时延方面表现更佳。

Multi-objective Signal Simulation Optimization for Urban Oversaturated Arterial

To resolve signal optimization problem of urban oversaturated arterial,a traffic signal simulation optimization model was put forward by analyzing the impact of traffic control objective on vehicle queue.This model takes green split,phase sequence,offset and cycle length as optimized parameters.Meanwhile,vehicle average delay,system average queue-lane length ratio and system capacity are selected as optimized goal.In order to implement the model,a framework was constructed,in which the microscopic traffic simulation environment established by ourselves is used to acquire the evaluation index of special signal scheme.And the repeated individual problem of multi-objective optimization algorithm (NSGA II) is improved,thereby the simultaneous optimization of signal timing scheme of arterial intersections is comleted.Finally,the collected traffic data from arterial consisted of three intersections were used to verify the model.The experimental results indicate that the proposed model not only can effectively control the vehicle queue length and ba-lance the vehicle distribution,but also has better performance on the system capacity and average delay.