车路协同环境下基于动态车速的相位差优化模型

Dynamic speed-based signal offset optimization model within vehicle infrastructure integration environment

针对基于固定路段行驶车速的相位差优化模型在优化双向滤波时存在的不足,本文基于车路协同环境下车辆–信号控制系统双向、实时通信的运行环境,研究并建立了车辆动态速度与交叉口相位差的整合优化模型.首先,基于对上游交叉口流出的两类交通流,即饱和交通流和非饱和交通流运行特征分析,建立了速度与相位差相互影响关系模型,在此基础上,分别针对两种不同的交通流,以干道实时流量与速度乘积最大为目标,考虑初始排队清空时间,可变速度范围,和相位差取值空间等约束条件,建立了车辆速度与相位差的动态优化模型,从而实现干道交通流不停车通过量最大且延误最小的目的.最后,对比分析了本文模型与经典Maxband绿波优化模型及Synchro软件的信号协调控制优化方案,结果表明,相比其他两种典型优化方法,本文模型能显著提高双向绿波带宽并大幅减少停车次数,提高协调控制的效益.

In order to overcome the drawbacks of signal offset optimization model using link travel speed as a fixed parameter,in this paper,based on the real time communication between vehicle and signal controller within vehicle infrastructure integration environment,an integrated signal coordination control model has been proposed to optimize the dynamic link travel speed and signal offsets.Firstly,based on the theoretical analysis of two different types of traffic flows,i.e.,saturation flow and non-saturation flow discharged from upstream intersection,the mathematical formulations for describing the interactions between link travel speed and offset have been set up.Then,the product of output volume and link travel speed is employed as the objective of the proposed model for the two types of traffic flows.A set of constraints including initial queue length,rational scope of travel speed,and offset are developed to ensure feasibility of the integrated optimization model,hence maximizing traffic throughputs without stopping and minimizing traffic delays simultaneously.Compared with the results optimized by classical max-band model and synchro-program,the proposed model can remarkably improve the green wave bandwidth,decrease number of stops significantly as well as increase total coordinated benefits.