永磁轨道磁场不平顺对YBCO高温超导块材温升行为的影响

Effect of irregular magnetic field of permanent magnet guideway on temperature rise behaviors of YBCO high temperature superconducting bulk

永磁轨道磁场不平顺激扰下YBCO高温超导块材的内在动态温升行为对高温超导钉扎磁浮热稳定性及列车运行可靠性研究具有重要意义。本文基于自主研制的超导磁浮动态测试装置SCML-03搭建了超导块材温升检测平台,研究了不同运行工况时永磁轨道磁场不平顺激励下YBCO块材内部温升行为规律。实验表明,在不同速度磁轨磁场不平顺的动轨条件下,YBCO块材内部温度均表现出先快速升高而后逐渐趋于稳定的趋势,YBCO块材内部关键点的温升在0~3 K范围内波动;此外建立了永磁体磁化强度与空间磁场的数学关系,实现了对真实永磁轨道磁场波动的模拟,基于Comsol Multiphysics有限元软件构建了真实动轨磁场不平顺下高温超导块材电磁-热-力多物理场耦合仿真模型。实验对比验证了磁轨磁场不平顺模拟方法和多场耦合模型的有效性,为下一步研究高温超导钉扎磁浮磁轨不平顺设计限值标准提供了前期基础。

The internal dynamic temperature rise behavior of the YBCO high temperature superconducting(HTS)bulk under the excitation of permanent magnet guideway(PMG)magnetic field irregularity is of great significance to the thermal stability and train operation reliability research of HTS pinning maglev.In this paper,an on-board superconducting bulks temperature rise detection platform was built based on the self-developed superconducting maglev dynamic test device SCML-03.The internal temperature rise behavior rule of the YBCO bulks under the excitation of PMG magnetic field irregularity at different operating working conditions was studied.The experiments show that the internal temperature of the YBCO bulks shows a trend of increasing rapidly and then gradually becoming stable under the dynamic guideway conditions of PMG magnetic field irregularity at different speeds.The temperature rise at internal key points of the YBCO bulk fluctuates within the range of 0~3 K.In addition,the mathematical relationship between the magnetization of permanent magnet and the magnetic field in space was established to reproduce the real PMG magnetic field fluctuation,and then a HTS bulks electromagnetic-thermal-force multi-physics coupling simulation model under real dynamic guideway magnetic field irregularity was established in Comsol Multiphysics finite element software.The validity of the PMG magnetic field irregularity simulation method and the multi-field coupling model are verified through experimental comparison,which provides a preliminary basis for the next research on the design limit standard of HTS pinning maglev magnetic track irregularity.