An Integrated Optimization Approach For Train Energy Consumption And Passenger Transfer Time

Urban rail transit is favored by urban residents because of its advantages of energy saving,high efficiency and environmental protection.However,compared with other public transportation systems,the rail transit system is high in energy consumption and cost.Among them,the energy consumption of train operation accounts for about half of the total energy consumption of urban rail transit system.Therefore,it is of great significance to reduce the energy consumption of train operation to reduce the total operating cost of rail transit system.With the large-scale expansion of rail transit lines,its operation mode gradually tends to network operation.Transfer is common in network operation,and the transfer process will bring extra travel time to passengers.Therefore,transfer time is usually an important index to measure the level of rail transit service.Considering the train schedule directly affects the energy consumption of the train and the transfer time of passengers.On the basis of the existing research,according to the train operation characteristics,this paper adjusts the train schedule of each line in the line network to improve the utilization rate of renewable energy and realize the energy-saving operation of the train.At the same time,the coordination between the lines should be taken into account to reduce passenger transfer time.The main contents of this paper are as follows:(1)A collaborative optimization model of train operation energy consumption and passenger transfer time was established.In the model,on the one hand,based on regenerative braking technology,the stopping time of the train at the station is determined,and the accelerating train and the braking train in the same power supply region on a single line are coordinated,so that the renewable energy generated by the braking train can be directly transmitted to the accelerating train for use.Thus,the actual energy absorbed by the accelerating train from the substation is reduced.On the other hand,through the change of the train’s stop time at the station,the coordinated transfer train can reduce the passengers’ transfer time at the arrival and departure time of the transfer station.According to the model,a genetic algorithm was designed to solve the problem,and a case study was carried out based on the actual data of Beijing metro yizhuang line and line 5.The results showed that: before the optimization,the optimization method could reduce the total energy consumption of the rail transit system by 5.15% and the total transfer time by 17.66%.(2)A collaborative optimization model considering interval running time was constructed.In the model,based on the previous research content,on the basis of the energy saving speed curve of each interval running time,by making decisions on the interval running time and stopover time of trains,the scope of train coordination and scheduling can be expanded,and the train running energy consumption can be reduced and the passenger transfer time can be reduced.A genetic algorithm was also designed to solve the model,and an example was given to show that before the optimization,the optimization method could reduce the total energy consumption of the system by 6.72% and the total passenger transfer time by 19.12%.