Delay-feedback control strategy for reducing CO2 emission of traffic flow system

•We proposed a new relative speed discrete coupled map car following model with proportional term.•We designed a delay-feedback controller to suppress traffic jam based on discrete control theory.•We studied the signal control strategy to reduce the CO2 emissions for traffic flow system.•The new model can describe dynamical characteristics of traffic flow system with more details.•Effective signal control strategy can greatly decrease CO2 emission.

To study the signal control strategy for reducing traffic emission theoretically, we first presented a kind of discrete traffic flow model with relative speed term based on traditional coupled map car-following model. In the model, the relative speed difference between two successive running cars is incorporated into following vehicle’s acceleration running equation. Then we analyzed its stability condition with discrete control system stability theory. Third, we designed a delay-feedback controller to suppress traffic jam and decrease traffic emission based on modern controller theory. Last, numerical simulations are made to support our theoretical results, including the comparison of models’ stability analysis, the influence of model type and signal control on CO2 emissions. The results show that the temporal behavior of our model is superior to other models, and the traffic signal controller has good effect on traffic jam suppression and traffic CO2 emission, which fully supports the theoretical conclusions.