The traffic flow controlled by the traffic lights in the speed gradient continuum model

In this paper, we have studied the traffic flow controlled by the traffic lights on a circuit road using the SG model. The single light situation, the synchronized light strategy, the green wave light strategy and the random switching light strategy are investigated. The spatio-temporal patterns are presented. Our simulations show that the plot of flow against density depends mainly on the distance between the lights and the cycle time. The capacity decreases with the increase of cycle time. For small distance between the lights, the lights do not behave as a bottleneck and the plot of flow against density looks just like a fundamental diagram. For the non-equidistant traffic lights situation, the results depend on the distribution of the distance between the lights.