Electromagnetic and thermal analysis research of high-order-mode coupler for 1.3 GHz 9-cell high performance superconducting cavity
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摘要: 中国科学院高能物理研究所于2023年6月完成了高品质因数1.3 GHz超导加速模组研发,在国际上率先实现了中温退火高品质因数超导腔模组技术路线。模组中集成了八只经过中温退火工艺处理的1.3 GHz 9-cell超导腔,在模组的测试过程中超导腔的高阶模耦合器温升异常,导致超导腔无法在高梯度下稳定工作。通过HFSS软件和CST软件中的微波仿真模块对高阶模耦合器进行电磁分析,再通过理论和Ansys Workbench软件对高阶模耦合器进行热仿真分析,并结合模组的高功率实验,找到了超导腔性能异常的原因,并对超导腔高阶模耦合器的冷却方式进行了进一步的优化,解决了模组中超导腔高梯度下的不稳定性。
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关键词:
- 1.3 GHz 9-cell超导腔 /
- 高阶模耦合器 /
- 电磁分析 /
- 稳态热分析
Abstract: The Institute of High Energy Physics of the Chinese Academy of Sciences completed the research and development of the high quality factor 1.3 GHz superconducting cryomodule in June 2023, taking the lead in the world to realize the technical route of the medium temperature baking. Eight 1.3 GHz 9-cell superconducting cavities with the medium temperature baking process are integrated. During the integration test of the cryomodule, the temperature of the high-order mode (HOM) coupler of the superconducting cavity was abnormal, which made the superconducting cavity unable to work stably under high gradient. In this paper, the electromagnetic analysis of the high-order-mode coupler is carried out by the HFSS software and eigenmode Solver in CST software and the thermal analysis of the high-order-mode coupler is carried out by theory and Ansys Workbench software. Combining with the high-power experiment of cavity, the cause of the abnormal performance of the superconducting cavity was found. Also, the cooling structure of the HOM coupler in the superconducting cavity was further optimized to solve the instability of the superconducting cavity under high gradient in the module. -
表 1 1.3 GHz模组两次测试腔因热锚导致可用梯度的变化对比
Table 1. 1.3 GHz modules’ usable cavity gradient contrast because of the connection of anchor in two tests
CAV# usable gradient of the
first test/(MV·m−1)usable gradient of the
second test/(MV·m−1)1 15 26.6 4 18.1 27.7 5 9 26.5 -
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