Modeling Toll Lanes and Dynamic Pricing Control
For transportation engineers, this work addresses the practical challenge of implementing dynamic toll pricing, though it is incremental as it combines known methods.
The paper proposes a dynamic pricing mechanism for toll lanes, combining supply-side feedback control to compute desired traffic split ratios and demand-side price setting via Value of Time distribution or auction. The auction approach enables direct control over toll lane access.
In this paper we address the problem of dynamic pricing for toll lanes on freeways. The proposed toll mechanism is broken up into two parts: (1) the supply side feedback control that computes the desired split ratios for the incoming traffic flows between the general purpose and the toll lanes; and (2) the demand side price setting algorithm that aims to enforce the computed split ratios. The split ratio controller is designed and tested in the context of the link-node Cell Transmission Model with the modified node model of in/out flow distribution. The equilibrium structure of this traffic model is presented; and the case, in which the existence of a toll lane is meaningful, is discussed. For the price setting, two alternative approaches are presented. The first one is commonly used, and it relies on the known Value of Time (VoT) distribution. Its shortcoming, however, is in the difficulty of the VoT distribution estimation. The second approach employs the auction mechanism, where travelers make bids on places in the toll lane. The advantage of this approach is that it enables direct control over how many vehicles will be allowed into the toll lane.