关键词: 道路交叉口, Petri网, 建模, 仿真, 比较

Abstract: Discrete Petri nets and continuous Petri nets have their advantages and drawbacks：the former one is more accurate but more complex, while the latter one is less complex but also less accurate. As a combination of the both, hybrid Petri nets can avoid the disadvantages to some extent, and is very suitable for the modelling of traffic intersections. However, a quantitative comparison of discrete model and hybrid model is very less in previous contributions. In this paper, a top-to-bottom hybrid Petri nets modelling method for traffic intersections is proposed. Using a 4-phases intersection as example, its hybrid Petri nets model is built and compared with the pure discrete one. By simulating the system under different workload settings, it observes the queue-length of traffic flows inside intersections and discusses differences between hybrid and discrete models. To some extent, it provides the quantitative criteria of selecting an appropriate kind of model.

Key words: traffic intersection, Petri nets, modelling, simulation, comparisons