FREEWAY TRAFFIC CONTROL BASED ON THREE-PHASE TRAFFIC THEORY

Abstract

Based on a microscopic traffic model in the context of the author's three-phase traffic theory, control strategies for prevention of congested pattern emergence or congestion reduction at freeway bottlenecks are simulated. Control methods, which lead to congested pattern dissolution, are presented. Speed limitation control on a freeway section in free flow, which should prevent traffic congestion, is studied. It turns out that in some cases speed limitation rather than prevent the onset of congestion leads to induced congested pattern emergence at a bottleneck, whereas there is free flow at the bottleneck without speed limitation. In other cases, in contrast, speed limitation can suppress moving jam emergence, which occurs without speed limitation. These effects are associated with probabilistic character of traffic breakdown at the bottleneck as well as with very complex dynamic spatiotemporal features of congested patterns. Three-phase traffic theory can explain and predict all known spatiotemporal features of phase transitions and congested patterns observed in real traffic. Thus, microscopic simulation environment based on three-phase traffic theory is a high-value instrument in a study of different freeway traffic control strategies before they are introduced to the market.