Emergency Regulation For Passenger Flow In Interchange Station Via ATS Under Network Operation

With the rapid construction of urban rail transit(URT),many large cities or megacities have entered the stage of network operation.Compared with a single line,the complex nature of urban rail transit network(URTN)makes its operation more challenging.In daily operations,due to the existence of a large number of uncertain factors,emergencies affecting operation safety occur from time to time,and the highdensity operation of trains and the closed features of the URT system make it less resistant to emergencies.For serious emergencies,it is necessary to adjust the operation plan of trains in a timely manner,strengthen passenger flow management,and even coordinate management with other modes of transportation to avoid adverse events,such as operation disorder,large-scale stranded passengers,loss of life and property.Under the background of network operation,how to deal with emergencies in URT through emergency strategies needs to be improved urgently.Emergencies not only easily cause delays and difficulty in evacuation of passengers,but also quickly affect the associated lines through interchange stations when the passenger flow is large.Therefore,emergency regulation of interchange stations and their associated lines is the key to ensuring the operation safety of URTNs.Based on this,this thesis focuses on the operation safety of interchange stations.By analyzing the passenger flow characteristics of the interchange station,the train rescheduling function of automatic train supervision(ATS)systems and the passenger flow control method,the general mode of ATSs under the background of network operation(i.e.,network ATS)to deal with the emergency regulation of the passenger flow at the interchange station is put forward.And theories related to emergency regulation of the network ATS is further expounded by taking the study of three typical emergency scenarios as examples.Specifically,the main contributions of this thesis are summarized as follows:(1)By analyzing the passenger flow attribute,interchange relationship,interchange mode and passenger flow description model of the interchange station,the research foundation of the passenger flow emergency regulation of the interchange station is laid.By discussing the basic methods of emergency strategies including train rescheduling and passenger flow control,the basic emergency regulation models of the two are constructed.Combined with the network operation mode of URTs and the train rescheduling function of an ATS,the basic structure of the network ATS is studied,the emergency regulation mode of the network ATS to deal with the passenger flow of the interchange station is discussed,and three levels of emergency regulation for the network ATS are proposed,namely the emergency regulation with the priority of the interchange passenger flow,the emergency regulation with the control of the interchange passenger flow,and the emergency regulation with the cross-line service for interchange passenger flow.(2)Taking the common scenarios of train speed-limited as an example,on the premise of not affecting the normal operation of associated lines,the emergency regulation with the priority of the interchange passenger flow is discussed in the case of the failure duration is short and the interchange passenger flow is small.Based on the analysis of the scenario,aiming at the maximum number of passengers served and the minimum total delay for the failure line,taking the requirements of common train operation parameters under normal operation and speed-limited operation,driving mode switching,and passenger flow control indicators,etc.as constraints,a biobjective nonlinear optimization model is constructed.With the help of ε-constraint method and linearization techniques including formula derivation,big-M method,adding variables and constraints,the model is converted into a mixed-integer linear programming(MILP)model that can be efficiently solved with common solvers.Two algorithms for the MILP model are proposed,one directly obtains the emergency plan,the other obtains the train rescheduling plan with a minimum total delay first,and then obtains the inbound passenger flow control plan.The effectiveness of the methods is analyzed with two sets of simulation cases.(3)Taking the recovery periods of a disruption scenario as an example,the emergency regulation with the control of the interchange passenger flow is discussed in the case of large interchange demand.Through the analysis of the scenario,an interchange passenger flow control strategy based on skip-stop operation of trains on adjacent lines at interchange stations is introduced.Aiming at the maximum number of passengers served on the disruption line,taking the related restrictions such as common train operation parameters and the operation efficiency for trains on the failure line,the train skip-stop operation on adjacent lines,and passenger flow control indicators as constraints,a collaborative optimization model considering the control of interchange passenger flow is constructed.According to the proposed linearization theorem,the nonlinear model is reconstructed into a MILP model.The corresponding algorithm is designed in conjunction with the Gurobi solver.The validity of the model and algorithm is verified by carrying out simulation case analysis.(4)Taking the scenarios of outburst mass interchange passenger flow as an example,the emergency regulation with the cross-line service for interchange passenger flow is discussed based on extra cross-line train.Based on the analysis of the scenario,aiming at the maximum number of passengers served via extra cross-line train,taking the requirements of common train operation indicators and the timetable deviation degree of determined trains,the utilization and the operation indicators of extra cross-line trains,and passenger flow description,etc.as constraints,a collaborative optimization model considering the cross-line service for interchange passenger flow is constructed.Combined with the linearization lemma that has been strictly mathematically proved,the nonlinear model is reconstructed into a MILP model.Based on the proposed algorithms,simulation cases are carried out.Meanwhile,the influence of parameters on the objective function value and the applicable condition of different methods are discussed.