Study On Energy Consumption And Emission Model Of Mixed Traffic Flow Of Fuel And Electric Vehicles At Signalized Intersection

At present,mobile source pollution has become the main source of air pollution in large and medium-sized cities in China.As the main traffic bottleneck of urban road network,signalized intersections will produce more energy consumption and emissions when vehicles pass through,while electric vehicles can achieve "zero emission" in the process of driving.Therefore,quantitative research on energy consumption and emissions of mixed traffic flow of fuel vehicles and electric vehicles at signalized intersections is of great significance to alleviate energy consumption,reduce exhaust emissions and realize carbon neutralization as soon as possible.The vehicle operating conditions at signalized intersections are extracted from the fusion data of radar and vision.The weighted KNN algorithm is used to divide the vehicle passing through signalized intersections into four types.The speed,acceleration,VSP and other parameters of various passing modes are calculated and analyzed.Combined with VSP theory and force balance principle,the energy consumption and emission models of fuel vehicles and electric vehicles at signalized intersections are established respectively,and the two models are integrated into a vehicle energy consumption and emission model of mixed traffic flow of fuel vehicles and electric vehicles.The intersection of Suyuan Avenue and qingshuiting West Road is taken as an example for analysis.In order to make up for the insufficient coverage of the actual collected data for different traffic situations,the measured data is used to check the VISSIM related parameters,so as to obtain the simulation vehicle operation data under various traffic situations close to the actual operation state of the vehicle.Combined with VISSIM simulation data and mixed traffic flow energy consumption and emission model,this paper evaluates the energy saving and emission reduction effect of signalized intersection vehicles under different mixed traffic proportion and different traffic conditions.The main research results are as follows:(1)By comparing various traffic information sensing devices,radar and vision fusion detector are selected as sensing devices to obtain vehicle operation data at signalized intersections.Through the threshold method for data cleaning,the acceleration,VSP and other important parameters are further obtained.Based on the idea of "classification first and regression later",this paper uses the weighted KNN algorithm to divide the vehicle passing through signal traffic into four types: accelerating passing,decelerating passing,stopping passing and normal passing.The regression analysis of vehicle speed under different passing modes is carried out,including normal fitting,gamma fitting,logistic fitting and Weibull fitting.The box-plot is used to analyze the speed concentration trend and dispersion degree,The distribution characteristics of acceleration and VSP are analyzed and explained.It provides data basis for the establishment of energy consumption and emission model of mixed traffic flow.(2)Based on the VSP theory,the fuel consumption and emission model of fuel vehicles is established,and the vehicle speed and time data passing through the intersection after parking are fitted to obtain the VSP change curve of vehicles in the deceleration stage and acceleration stage.Based on the control delay model of transition function theory,the cumulative idle time of vehicles is derived,and the incremental emission and energy consumption model of fuel vehicles is established.Based on the principle of force balance,the energy consumption model of electric vehicle is established,and the emission model of electric vehicle is established combined with the power consumption and emission factors.The energy generated by braking in deceleration phase and the energy consumed by components in acceleration phase,uniform speed phase and idle speed phase are calculated,and then the incremental energy consumption and emission model of electric vehicle are obtained.Finally,the energy consumption and emission models of fuel vehicles and electric vehicles are integrated to establish the average energy consumption and emission model of mixed traffic at signalized intersection,and the intersection of Suyuan Avenue and qingshuiting West Road is taken as an example for analysis.The results show that the average carbon emissions of fuel vehicles and electric vehicles at the signalized intersection are124.8969 g and 34.2542 g respectively,the average energy consumption value of vehicles is0.3593 yuan and 0.0268 yuan respectively,and the average incremental energy consumption of vehicles at each entrance road is 56.98%～64.99% and 47.57%～51.86% of the total energy consumption respectively.(3)The simulation signalized intersection is established by vissim7.0 traffic simulation software,and the saturation flow rate is checked by using parameters a and B.the default saturation flow rate is about 1600.Based on the measured headway and other parameters,the acceleration curve of the vehicle and other driving behavior parameters are checked,such as forward / backward viewing distance,average parking distance,distraction,the number of observed vehicles and other parameters.By comparing the accumulated headway of straight ahead vehicles in the simulation model before and after verification with the actual value,it shows that the simulation vehicle operation after verification is closer to the actual situation.Based on the change curves of vehicle speed,acceleration and deceleration obtained from the fuel vehicle energy consumption and emission model,the energy generated by braking in deceleration phase,and the energy consumed by various components in acceleration phase,uniform speed phase and idle speed phase are obtained,and then the incremental energy consumption and emission model of electric vehicle is obtained.The results show that the average error before and after checking is 36.98% and 2.68% respectively,and the operation of the simulation vehicle after checking is closer to the reality.(4)Based on the vehicle operation parameters obtained by VISSIM simulation under different traffic conditions,combined with the vehicle energy consumption and emission model of mixed traffic flow at signalized intersection,the vehicle energy consumption and emission under different traffic conditions are calculated,and the influence of different mixed traffic proportion,different signal cycle,green signal ratio,vehicle arrival rate and other traffic parameters on vehicle energy consumption and emission is analyzed.It provides a theoretical basis for evaluating the impact of future electric vehicle development on energy and environment at signalized intersections.The results show that the energy consumption value and carbon emission of electric vehicles through the same signalized intersection in different traffic scenarios are about 7.62% ～ 7.89% and 25.86% ～ 28.46% of that of fuel vehicles.The energy saving and emission reduction effect of increasing the proportion of electric vehicles is better than that of timing optimization.