关键词: 城市交通控制, 传递函数模型, 系统辨识, 交叉路口

Abstract: A general model structure is proposed to describe urban traffic flow in order to study the dynamic characteristics of the traffic flow.Some typical dynamic units are presented to describe the traffic flow of an intersection，which are the representation of the road network traffic flow.The study is carried out by means of simulation experiments.In order to get the input/output data of the simulated traffic flow under different conditions，many different simulation experiments are designed.Using the input/output data，the transfer functions model of the traffic flow at intersection is put forward based on the methods of system identification.The research shows that the transfer functions of the cycle control channels are three-order systems；the transfer functions of the split control channels are two-order systems.The transfer functions model can describe the states of traffic flow of an intersection，and it can be used to study the dynamic characteristics of the traffic flow.

Key words: urban traffic control, transfer functions model, system identification, intersection