A Number Of Studies Of Expressway Control

Expressway traffic control is considered as an important issue of the traffic engineering fields,but also an important component of intelligent transportation system with the process of urbanization gradually acceleration. For the drawbacks of traditional traffic control technique,people have begun to apply advanced theories and techniques to expressway traffic control in recent years.This paper firstly discussed model predictive control of the freeway traffic in detail,then made a detailed analysis and reseach to the corridor control.The main work and research results of this paper are as follows:(1) Firstly, because of nonlinear model predictive control with three major advantages of model predictions,the feedback correction and rolling optimization, it is adopted to slove the coordinated control of multiple sections on freeway,aimed at the characteristics of non-linearity,hysteresis,and internal coupling. Simulated results show that this method has a improvement on the efficiency and a smoother metering rate,and can effectinately eliminate traffic jams and maintain stablility of main traffic flows. At the end,the equity of it is analyzed.(2) then, corridor control method is proposed aiming at interaction of freeway and connected parallel nonfreeway.The advantages of corridor control method is not only taking into account the coordinated control of all interaction ramps but also coordinated control of freeway and nonfreeway. numerical solution are presented ane show that efficiency has been more improved than without control and centralized control.Model predictive control and corridor control presented in this paper have more efficiency than without control results,so both control methods have great significance to improve the capacity and operational efficiency of the freeway.