An Energy-efficient Approach By Integrating The Train Timetable And Speed Trajectory In Urban Rail

Energy-efficiency and low carbon emission are the key targets for urban rail which caters to the national sustainable development policy,increasing the competi-tiveness of rail transportation,as well as reducing the operational cost.The traction en-ergy accounts for the most important part in the energy consumption of the system and it will be of great significance to study the related energy-efficient technic and methodology.Train timetable and trajectory are two important elements to determine the energy con-sumption of the train operation by influencing the utilized traction energy consumption and reused regenerative braking energy.With the development of automation,informa-tion fusion technology,and the fast computation speed of computers,increasing attention is being paid to the integration of the train timetable and train trajectory for urban rail.Based on the characteristic of the train timetable and the train operation in urban rail,the energy-efficient train operation in urban rail is divided into three levels,i.e.,the train trajectory,train running time,and the train timetable.Based on the integration methodology and the train operation characteristic,the integrated modes for the integrat-ed train operation is proposed,which takes the closed-loop integrated approach for the train timetable and train trajectory as the research focus.When the integration approach is implemented,the low level of the train operation should be firstly studied in the thesis,which is taken as the input of a higher level.Specifically,based on solution to the opti-mal solution to the train trajectory problem,an integrated approach for the train running time optimization is proposed such that the single train operation approach is achieved.Then,the multi-train optimization approach is presented as an extension of the single train optimization approach based on the integrated approach.This thesis focuses on studying the integrated approach of the train timetable and train trajectory based on the related theories and characteristic.Specifically,the main targets of the thesis are as follows:·(1)Based on the classic train trajectory optimization theory and the traction effi-ciency characteristic of the trains in urban rail,the energy-efficient regimes and the corresponding sequences are reanalyzed.By using the Parato method,a numerical algorithm is proposed to calculate the switching points of different regimes.The method for applying this theory into practical ATO systems is considered according to the ATO control principle.·(2)Train running time is the key relation between the train timetable and train trajectory.This thesis will study the integrated approach for the train trajectory and train running time.A model of optimizing the train running time is proposed for a single train and the algorithm for distributing the reserve time to multiple segments is considered.The energy consumption for a single train in multiple segments is minimized with the given total running time.·(3)Based on the energy-efficient train trajectory and the integration methodology,a cooperative train control model is proposed with considering the regenerative braking.With the operation information of the successive braking train,a running time optimization model for the traction train is developed,in which the net energy consumption is minimized by efficiently utilizing the regenerative energy through a good cooperation.·(4)On the basis of the single train optimization approach,an integrated timetable optimization approach is proposed.Two models with and without considering the regenerative energy are studied for multiple trains to reduce the traction energy consumption and the net energy consumption of the system,respectively.·(5)For each optimization problem,simulations are made based on the infrastruc-ture and operation data to illustrate the effectiveness of the proposed approach.