Study On Emission Reduction Effect Under Different Speed Guidance Strategies At Signalized Intersection

Since the new century, environmental issues are on the rise, and as an important source of urban pollution, traffic pollution also has been more and more attention. Due to the impact of signal control, vehicle start-stops and idle speed contribute on the high emissions and high energy consumption at the intersections. With the continuous promotion of cooperative vehicle infrastructure system, speed guidance strategy can provide reasonable speed recommendations to drivers for going through the intersection smoothly, taking advantage of vehicles'spatial and temporal trajectories and corresponding signal timing parameters.This study established a low emission oriented speed guidance model introducing fuzzy control and a speed guidance model considering the turning limit speed, based on traditional green wave speed guidance model. In order to explore the strategy influence on emissions and energy consumptions, microscopic traffic simulation software VISSIM and its secondary development was used to realize simulation environment under the speed guidance strategy and through the collected driving characteristic data and microscopic emission model MOVES, energy consumption and emission could be estimated. For the experimental results, the comprehensive index of total weighted cost was applied to evaluation the effect. As a case study, the intersection at Lianhe Road crossing Changjiang Road in Dalian was selected.Comparing the emissions of different driving behaviors after receiving the green wave guidance, the results show that acceleration behavior causes 50% more emissions and deceleration behavior causes 30% less emissions. The establishment of the fuzzy controlled speed guidance model is for the purpose of restricting the higher emissions. Compared with green wave one, traffic emissions and energy consumptions decrease by 3%?5% with the low emission oriented speed guidance strategy in different traffic volumes.In order to research the effect degree of speed guidance strategy in a more realistic environment, the research set up different strategy acceptance rates, and the results show that the effect of the strategy is directly proportional to the acceptance rates basically, but at a high flow rate there are certain fluctuations. Then the guidance control distance were analyzed. The experimental results can get optimal control distance, which not only ensures the running effect of the strategy but also is a shorter one, and in this study the optimal control distance is 500m. The result provides a theoretical basis for roadside equipment optimization layout. In the end, the experiment was carried out with the guidance of the lane. The conclusion points out that although the effect of single lane guidance is less than the one of two lane guidance, the first one can reduce emissions and energy consumption in the high traffic volume.