Energy Consumption Simulation And Application For Highway Multi-point Tollbooth Traffic Flow Based On Cellular Automaton

In recent years, rapid progress has been witnessed in the China’s high-grade highways. Bythe end of2012, our country’s highway mileage has reached97355km,14.6%more than lastyear. Under the policy of “loaning for expressway and charging repay a loan”, the main tollcollection for high-grade highways directly relates to highway traffic efficiency and economicbenefits. Implementing the resource-saving and environment-friendly society as well asaccelerating the construction of green transportation system has been set forth as a goal in the“Twelfth Five-year” transportation development plan. However, traffic congestion, safety andenvironmental problems in toll system have become increasingly prominent. Vehicles passingthe toll system are often in a “stop-go” and queued state, consuming a mass of energy.Related research shows that more than20%of the oil consumption and air pollution are dueto traffic congestion and “stop-go” traffic, and the fuel consumption will increase by2～4times when vehicle velocity reduces from40km/h to10km/h. Though Electronic TollCollection （ETC） can improve the traffic capacity of toll station, the system is difficult todeploy in China’s economic level and application conditions. Moreover, most vehicles payingthe toll in our country are still Manual Toll Collection （MTC） vehicles. Multi-point tollboothadds multiple sets of toll facilities on the basis of the existing toll facilities, achieving thefunction of charging multiple vehicles in each lane. The charging mode greatly reduces tollsystem investment, improving the capacity of the toll system and reducing the energyconsumption of the traffic flow.Considering the driving characteristics of vehicles passing multi-point tollbooth, the paperestablishes the evolution rules of vehicle state on the basis of classical NaSch model.Additionally, adding the factor of idling energy consumption, the traditional vehicle energyconsumption model was improved in this paper in view of the particularity of vehicletraveling state when passing multi-point tollbooth. Lastly, a multidimensional CA model formulti-point tollbooth traffic flow and energy consumption was proposed, on the basis ofwhich, the paper analyzes the influence of MTC/ETC vehicles and toll booths setting rules ontraffic flow and energy consumption on a single lane, making the following conclusions:（1） The impacts of mixed ratio R, the value of E_s, the maximum velocity V_max of the vehicle,dwell time Twand random deceleration probability p on multi-point tollbooth traffic flow andenergy consumption.Under R≠0, each flux curve has two peaks, the second peak is its maximum flux. As thevalues of R, T_w and p increase, more and more serous clogging of the vehicles near thetollbooth, and more difficult the phase transition from the jam phase to the free flow phase.Nevertheless, the flux curve is independent of V_max. When the values of R, T_w, p, V_max and E_s increase, the total energy consumption E_d increases accordingly, and the varying tendency ofidling energy consumption is consistent with E_d curve.（2） The impacts of booths number M, the booths setting position and booths arrangementmode on multi-point tollbooth traffic flow and energy consumption.As M increases, the capacity of multi-point tollbooth gets larger with lower amplitude,existing a critical number M=7, where the capacity is about50percent higher than that oftraditional toll station. In addition, the flux curve is independent of the booths setting position.when the gap between the first two booths from vehicles approaching direction gets larger,the peak flux increases within the critical range. Additionally, as M increases, the total energyconsumption drops with lower amplitude. Numerical tests indicate that booths setting positionand arrangement mode show less impact on vehicle energy consumption.