Comparison of Controllers for Variable Speed Limit Using Realistic Traffic Scenarios

Urban motorways are designed to serve higher traffic loads but rush hours are causing periodically unstable traffic flows and congestions. Variable Speed Limit Control (VSLC) can alleviate congestion by posting appropriate speed limits on Variable Message Signs. In this paper, three controllers for VSLC are compared using a simulation model based on real traffic data obtained from the PeMS database collected at a selected motorway of the State of California, USA. The results show that the implemented VSLC controllers have the ability to improve the traffic condition in case of higher traffic intensity compared to an uncontrolled case.