Operation Strategy Optimization Of Medium-Speed Maglev Integrating Operation,Train Control,and Linear Motor Control

As a new rail transportation mode with wide application prospects,medium-speed maglev(MSM for short)serves the large-volume and high-density passenger flow in metropolitan area with the operation speed of 200 km/h.In order to enhance the commercial competitiveness of MSM with respect to operational efficiency and energysaving,it is necessary to optimize the operation strategies of MSM system in the planning,design and operation phases.Therefore,this thesis discusses a three-layer MSM optimization strategy integrating operation,train control,and linear motor control(i.e.train timetable,train speed profile,and linear motor control strategy)to achieve efficient and energy-saving operation of MSM.The strategy also provides theoretical support for the planning,designing and opeation of the MSM.(1)The eigenmodel of MSM operation strategy optimization integrating the operation,train control,and linear motor control.We analyze the working principle of the MSM system,followed by a discussion of the parameters associated with the efficiency and energy consumption of MSM train operation,as well as their relationship.We propose an eigenmodel of the integrated optimization problem including key decision variables concering time,speed,and electrical parameters.To solve the eigenmodel describing an overly complex combinatorial optimization problem,we propose a layered solution approach,namely “beginning at the middle,depth first and width last,detailed first and general last”.Specifically,we first study the target speed profile optimization of a single MSM train.With the derived optimized train speed profiles as references,we study the integrated operation strategy optimization problem of train control and linear motor control by investgating the relationship between train speed and electrical parameters of linear motors at the power supply level.Furthermore,the research object is expanded from a single train to a train cluster at the operational level,and yields the operation strategy optimization problem of operation,train control,and linear motor control of MSM,to obtain an efficient and energy-saving holographic timetable.(2)The train speed profile optimization of MSM.With the study object of a single MSM train,we analyze the MSM dynamics model.Considering the impact factors of train operation(including maximum traction and braking force,running resistance characteristics,maximum speed limit,two-dimensional speed protection and slope,etc.),we model the optimization problem of the target speed profile of the MSM train with the objective of minimizing mechanical energy consumption,and propose two solution approaches,namely dynamic programming-based algorithm,and mixed integer programming-based algorithm to solve the model.(3)The integrated operation strategy optimization problem of train control and linear motor control of MSM.Based on the research conclusions of the single train target speed profile,we "deep" down to the linear motor at the power supply level.According to the derived train target speed profile,an cut solution space of train speed is generated,based on which the integrated operation strategy optimization problem of train control and linear motor control of MSM with the objective of minimizing traction energy consumption is constructed.We propose an equivalent model of the long stater linear motors,mechanical systems and operating resistance characteristics under rotor-oriented magnetic field control mode.Combining the train dynamic operational formulation,we construct an integrated operation strategy optimization model of train control and linear motor control of MSM with the motor simulation to obtain a refined train speed curve.(4)The comprehensive optimization of the operation strategy of operation,train control,and linear motor control of MSM.The research object is expended from a single train to a train cluster at the operation level.We study the operation strategy optimization problem of operation,train control,and linear motor control of MSM.A train timetable with the objective of minimizing the total travel time of passengers and operation energy consumption is obtained.Considering the relationship between the load factor and energy consumption(suspension energy consumption + traction energy consumption),we propose a comprehensive optimization method of the operation strategy optimization problem of operation,train control,and linear motor control of MSM.This method consists of the following key steps,namely train departure time optimization,the generation of the candidate set of energy consumption and train mass linear regression formulation,train segment running time optimization,and detailed operation strategy generation and verification.The holographic timetable containing multi-dimensional data(i.e.time,space,speed and electrical quantity)is obtained.