高速公路多路段的模糊逻辑协调控制

采用递阶结构和模糊控制来解决高速公路多路段的协调控制问题.建立了宏观交通流有限差分模型,然后结合交通系统的特点提出一种多层控制结构,把高速公路的控制问题分为适应层、协调层和直接控制层,直接控制层采用模糊控制决定各匝道的调节率,协调层为直接控制层确定期望密度,适应层根据实时检测到的交通状况选择模型和调整模型参数.仿真结果表明,模糊逻辑协调控制具有良好的动态和稳态性能,该方法能够有效地消除交通拥挤,维持主线车流稳定.

Coordinated Fuzzy Logic Control of Multiple Sections on Freeway

In this paper, the hierarchical structure and the fuzzy control are adopted to solve the coordinated control of multiple sections on freeway. A finite-difference model of macroscopic traffic flow is first established. A multilayer control structure is then proposed according to the characteristics of traffic systems. In this structure, the control problems of freeway traffic systems are divided into three layers, that is, an adaptation layer, a coordination layer and a direct control layer. The direct control layer is in charge of the ramp metering rate via fuzzy control, the coordination layer determines the desired traffic density for the direct control layer, and the adaptation layer answers for the selection of traffic models and the adjustment of model parameters according to the real-time freeway traffic status. Simulated results show that the coordinated fuzzy logic control is of good dynamic and steady-state performance. This method can effectively eliminate traffic jams and maintain stability of main traffic flows.