面向超导钉扎磁浮的液氮液位检测方法研究现状

高温超导钉扎磁浮制式以悬浮导向一体化、自稳定、无需控制等优势得到了越来越多的关注.与其他磁浮制式不同,高温超导钉扎磁浮制式采用块状高温超导材料作为车载悬浮体,需要低温液体液氮作为悬浮单元的制冷剂,冷却方式为浴冷,因此实时监测液氮液面,保证液面平稳是未来超导钉扎磁浮车运行维护的首要需求.本文从车载高温超导YBaCuO块材所需的液氮环境及其配套的液氮容器功能和结构出发,结合我们近期的基于卡尔曼滤波(Kalman filtering,KF)滤波算法的铂电阻传感器液氮液位计研究工作,对6种低温液位检测方法的基础原理、特征及检测精度的对比分析,总结示出包括铂电阻阵列方式在内的3种适用于超导钉扎磁浮列车在线检测系统的液氮液位检测方法,用于推进我国2021年1月13日正式启用的高温超导钉扎高速磁浮工程化样车应用发展.

Research Status of Liquid Nitrogen Level Detection Methods Oriented to Superconducting Flux-pinning Magle

High-temperature superconducting (HTS) flux-pinning maglev has the advantages of the integration of levitation/guidance passive self-stabilization 9 little control and so on. It gets more and more attention. Different from other maglev Systems, HTS flux-pinning maglev employs bulk high temperature superconducting materials as the onboard levitation components which needs low-temperature liquid nitrogen (LN2) as the refrigerant of these levitation units. The general cooling method is bath cooling. Therefore 9 the real-time monitoring and stable maintenance of the LN2 level is a primary demand for the operation maintenance of future HTS flux-pinning maglev vehicles. Starting from the required LN2 environment for the onboard HTS bulks and the function and structure of the matched cryostat, six applicable liquid level detection methods are summarized based on our recent research on the platinum-resistance-sensor (PRS) liquid level detection combined with Kalman filtering algorithm. Three liquid level detection methods were concluded including the PRS array method. And these methods can be employed to promoter the application development of the newly-launched HTS flux-pinning high-speed engineering prototype vehicle in China on 13 January 2021.