MFAC Based Balance Control For Freeway And Auxiliary Road System

Freeway and auxiliary road system undertakes a large amount of traffic tasks in the traffic network of big city. In recent years, with the rapid development of urban economy, motor vehicles have also increased rapidly. More and more vehicles swarm into the freeway and auxiliary road, so traffic congestion and traffic flow difference could be seen often. Therefore, reasonable and effective traffic control must be implemented to ensure the operation of traffic system efficient and balanced.At present, freeway and auxiliary road are separately controlled among most researches on the freeway and auxiliary road system control while the study of balance control on freeway and auxiliary road system is less. The existing methods of balance control rely on the freeway and auxiliary road model very much and are difficult adapted to the change of the structure and parameters of the nonlinear traffic system. Therefore, basing on MFAC theory, balance control on freeway and auxiliary road system is studied in this thesis.The main work of this thesis is as follows:Firstly, Papageorgiou’s discrete macroscopic traffic flow model is introduced as freeway traffic flow model and auxiliary road traffic flow model is established basing on the store-and-forward model.Secondly, local balance control and global balance control on freeway and auxiliary road system are studied. In local balance control research, with the difference of freeway and auxiliary road density as the control target, MFAC based local balance control scheme for freeway and auxiliary road system is proposed combining with the ramp control. Further considering the importance of freeway operation efficiency, MFAC based local balance control scheme for freeway and auxiliary road system with freeway priority is proposed. In the global balance control research, considering the idea of integrated control and combining with ramp control and multi-intersections coordinated control, MFAC based balance control scheme for freeway and auxiliary road with multi-intersections coordinated control is proposed. Further taking the effect of the coupling relationship between ramp and intersection on balance control into account, MFAC based ramp and intersection joint control scheme is proposed.Finally, in order to verify the effectiveness of the control schemes proposed in this thesis, the MATLAB simulation experiments of the control schemes are given on two traffic scenes with different road structure and traffic demand. The results show that MFAC based local balance control scheme for freeway and auxiliary road system can realize the balance of traffic flow near the ramp, but it cannot guarantee the operation efficiency of freeway traffic when the traffic flow increases. When the traffic demand is large, MFAC based local balance control scheme for freeway and auxiliary road system with freeway priority can preferentially ensure the operation efficiency of freeway traffic and realize the balance of traffic flow near the ramp. MFAC based balance control scheme for freeway and auxiliary road with multi-intersections coordinated control scheme eliminates density difference between freeway and auxiliary road, makes the traffic flow smooth and realizes the balance of density on freeway and auxiliary road as a whole. The effect of MFAC based ramp and intersection joint control scheme is better than the scheme with multi-intersections coordinated control, with more stable traffic flow, more balanced density and larger traffic service volumes.