Cryo-Free 7.0T Actively-Shielded ICR Spectrometer Magnet

描述（由申请人提供）： 研制用于离子回旋共振傅里叶变换质谱（ICR-FTMS）的无制冷剂、主动屏蔽7.0 T高分辨率超导磁体将显著降低系统运行成本并简化操作。生物科学家和遗传研究人员越来越依赖ICR-FTMS。所提出的FTMS主动屏蔽磁体系统将具有许多技术优点：超高分辨率、低系统运行成本（操作系统无需再填充冷冻剂），用户友好性（使用闭合循环制冷，CCR，光谱仪的磁体部分几乎无需维护），紧凑的尺寸（由于主动屏蔽，该系统可以适合小型实验室，并且低温恒温器将小得多，因为不需要冷冻剂存储体积），灵活性和机动性（无冷冻剂要求意味着冷冻剂获取和可用性问题将不再失去坐的限制）。 这项研究将集中在改善磁体稳定性问题，如持续模式下的时间场稳定性，最大限度地减少与低温冷却器相关的振动影响，以及在较低故障情况下系统的鲁棒性。将被考虑的其他领域包括改善传导冷却系统和低温恒温器，磁体的设计优化（包括磁场均匀性，屏蔽和应力分析），失超保护电路的设计，建立一个模型线圈，以提高冷却能力，并生成一个完整的工程设计的主动屏蔽无低温7.0 T磁体系统。 将使用现场已有的低温冷却器和低温恒温器对模型线圈进行测试。当整个线圈达到4.2K的平衡温度时，线圈将被缓慢充电到其设计的工作电流，然后永久开关将被锁定。该测试设置可以测量几个关键问题，这将有助于设计7.0 T磁体系统。

DESCRIPTION (provided by applicant): The development of a cryogen-free, actively-shielded 7.0 T high-resolution superconducting magnet for Ion Cyclotron Resonance Fourier Transform Mass Spectrometry (ICR-FTMS) will significantly reduce system operating costs and simplify operation. Bio-scientists and genetic researchers rely more and more on ICR-FTMS. The proposed FTMS actively-shielded magnet system will have many technological merits: ultra high resolution, low system operating costs (no cryogen refilling will be required to operate the system), user-friendliness (using closed cycle refrigeration, CCR, the magnet portion of the spectrometer becomes almost maintenance free), compact size (due to the active shielding, the system can fit into a small laboratory, and the cryostat will be much smaller since no cryogen storage volume is necessary), flexibility and mobility (no cryogen requirement means problems with cryogen access and availability will no longer lose sitting limitations). This study will focus on improving magnet stability issues such as temporal field stability in persistent mode, minimizing vibrational effects related to the cryo-cooler, and the robustness of the system in the event of a lower failure. Other areas that will be considered include improving the conduction-cooling system and cryostat, design optimization of the magnet (including field homogeneity, shielding, and stress analyses), design of quench protection circuits, building a model coil to improve cooling capabilities, and generation of a complete engineering design for an actively-shielded cryogen-free 7.0 T magnet system. A model coil will be tested using a cryo-cooler and cryostat that are already on site. Upon the whole coil reaching the equilibrium temperature of 4.2 K, the coil will be charged slowly to its designed operation current, then the persistent switch will be locked. This test setup can measure several key issues, which will help design the 7.0 T magnet systems.