有轨电车信号优先时长阈值优化模型

以车辆延误和交叉口饱和度为约束条件, 针对绿灯提前和绿灯延长2种优先策略, 建立了求解有轨电车信号优先时长阈值的优化模型, 考虑了有轨电车车身长度的影响, 通过案例对模型进行验证。分析结果表明: 绿灯提前策略下优先时长的阈值为0~13s, 绿灯延长策略下优先时长的阈值为5~11s;以出行者作为研究单元时, 不同的非优先相位的公交车辆数对应不同的整体效益曲线, 而以车辆作为研究单元时, 不同的非优先相位的公交车辆数只对应一条整体效益曲线; 非优先相位的公交车辆数的临界值为16veh, 非优先相位的车辆到达率的临界值为0.115pcu·s^-1, 红灯时长的临界值为101s, 这些参数超过临界值后, 不再适合给有轨电车设置信号优先。本文提出的有轨电车信号优先时长阈值的优化模型为给予有轨电车合理范围内的信号优先提供了依据。

Optimization model signal priority time threshold of tram

Vehicle delay and intersection saturation were taken as constraint conditions, early green and extended green priority strategies were used, and the model of solving signal priority time threshold of tram was built.The influence of tram length was considered, and the model was verified through real case.Analysis result shows that the priority time thresholds under early green strategy are 0-13 s, and the priority time thresholds under extended green strategy are 5-11 s.When travelers are regarded as research units, different bus numbers under non-priority phase correspond to different overall benefit curves.When vehicles are regarded as research units, different bus numbers under non-priority phase correspond to only one overall benefit curve.The critical value of bus number under non-priority phase is 16 veh, the critical value of vehicle arrival rate under non-priority phase is 0.115pcu·s-1, and critical value of red time is 101 s.When they exceed critical values, it is not suitable to set signal priority for tram.The optimization model of signal priority time threshold of tram in this paper provides basis for giving signal priority of tram within reasonable range.