高温超导磁悬浮准静态的力弛豫特性  

Quasi-Static Force Relaxation Characteristics of High Temperature Superconducting Magnetic Levitation

作　　者：刘晓宁[1] 柯志昊 邓自刚[1] LIU Xiaoning;KE Zhihao;DENG Zigang(State Key Laboratory of Rail Transit Vehicle System,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学轨道交通运载系统全国重点实验室,四川成都610031

出　　处：《西南交通大学学报》2023年第4期845-852,共8页Journal of Southwest Jiaotong University

基　　金：国家自然科学基金(52022086);四川省科技厅创新团队项目(2022JDTD0011)。

摘　　要：为了研究顶部籽晶熔融织构法制备的钇钡铜氧超导块材在Halbach永磁轨道上的准静态悬浮力弛豫特性,定义了弛豫完整过程,划分为激励过程(含起始状态、中间过程、终止状态)、弛豫过程和稳态结果;在激励过程起始和终止状态相同时,通过搭建的悬浮力测试装置,研究了复杂中间过程对稳态结果的影响;基于磁化和Anderson-Kim模型建立了弛豫分析模型,对力弛豫规律进行分析和总结.研究结果表明:4种不同中间过程位移形式的稳态结果趋于一致,但位移过程中的最大悬浮力受到往返次数以及速度的影响,其中最大悬浮力点分布在随时间对数衰减的曲线周围;弛豫过程前终止状态的悬浮力与移动速度正相关,经过弛豫过程后的稳态结果趋于一致,而弛豫过程后以不同移动速度重复往返一次,移动速度对最大悬浮力的影响明显减弱(最大悬浮力差值由3.7 N降低为2.0 N);超导体在激励过程和弛豫过程中皆存在弛豫现象,而移动速度以及往返次数对最大悬浮力的影响结果是激励过程力弛豫的表现.To investigate the quasi-static force-relaxation characteristics of a YBCO bulk levitated above a Halbach permanent-magnetic guideway,using the top-seed-melt-texture-growth method,the complete relaxation process is defined and divided into the excitation process(involved initial state,dynamics process,and termination state),relaxation process,and steady state.With the same initial and termination states,the effect of different displacements of the dynamics process on the steady state is experimentally investigated using a specialized apparatus.Then,on the basis of magnetization and the Anderson-Kim model,a relaxation model is established and several laws are formulated.The results indicate that the steady states of the four displacements tend to be the same.However,the maximum levitation force(MLF)is affected by the round-trip times and displacement velocity.The MLF points are distributed around a curve that decays logarithmically with time.Prior to the relaxation process,the levitation force of the terminating state is positively correlated with the velocity;the steady state results after the relaxation process tend to be consistent.Furthermore,after the relaxation process,the influence of the velocity on the MLF is greatly reduced(the MLF difference decreases from 3.7 N to 2.0 N).Relaxation phenomena are in both the excitation and relaxation processes of superconductors,and the effect of the velocity and round-trip times on the MLF is manifested in the relaxation during the excitation process.

关 键 词：磁悬浮 高温超导体 弛豫过程 悬浮力 准静态 

分 类 号：U266.4[机械工程—车辆工程]