Distributed Fixed-time Cooperative Control Method For High-speed Train Formation

High-speed railway is an important part of the modern transportation system,which has the advantages of strong transportation capacity,ride comfort,and green environmental protection.With the increase of total railway transportation,transportation capacity cannot satisfy the realistic needs of the transportation,and the realization of train formation operation is an important method to improve the transportation capacity.It is of great significance to design an appropriate control strategy for train formation under the complicated and changeable environment situation.So based on the fixed-time control,this paper focuses on the research of train formation and designs the train formation cruise control method,the control approach of train formation reconfiguration,the control strategy for hybrid train formation.And compared with PID control and prescribed performance control,these methods can provide explicit estimation of system convergence time.The contribution of this paper is as follows:Firstly,the problem of distributed fixed time cruise control for train formation under flexible intervals is researched.Based on the principle of moving block soft wall,the calculation model for tracking interval of train formation is established.The relationship between the headway time and the tracking interval of train formation is studied,and the calculation method of the minimum headway time is given.Considering that the coupling relationship between trains in the formation constrains the position and speed of trains,a distributed fixed time cruise controller with virtual parameter adaptation estimation method for train formation is designed,which solves the uncertain external resistance and complex circuit conditions problem in the train formation dynamics model.The proposed method can achieve the target that the train formation can reach the desired cruise speed from a different state in a determined time,and maintain stable formation cruise running.Secondly,based on fixed time theory,the problem of train formation reconfiguration is studied.Considering the following train joins the train formation to make the formation reorganize,a train formation fixed time reconfiguration control strategy is proposed.The advantages and disadvantages of different strategies to join the formation for the following train are compared.And a novel train reconfiguration control strategy is designed for the following train to join the train formation as the rear one.According to the tracking distance between the train formation and the following train,the switching controller design for the following train is divided into three steps which are accelerating to reduce the distance,slowing down for adjustment,and cooperative operation.Consequently,the train formation realizes the objective of formation reconfiguration.Finally,the distributed fixed time control for hybrid train formation is addressed.The train formation is composed of different trains,which exists different mass and has different traction and braking performance.A novel distributed control method is proposed for train formation with heterogeneous trains.Through analysis,it is known that the trains in the train formation have a common running goal,that is the train speed and tracking interval should be consistent.Based on this,a distributed fixed time observer is designed for each train in the train formation to realize the estimation of the target speed curve of the leading train in a determined time.And then a distributed tracking controller is designed for the train formation to track the target speed curve in a settling time.As a result,the cooperative control problem for the train formation is solved.The simulation results demonstrate that the proposed method can realize the cooperative operation of train formation with heterogeneous trains.There are 72 figures,2 tables,and 91 references.