Horizontal test of 500 MHz superconducting cavity for SSRF
-
摘要: 上海光源是能量为3.5 GeV的第三代先进中能同步辐射光源,其储存环上安装了三台超导高频腔补偿电子因同步辐射等原因丢失的能量。为保障上海光源的长期稳定高效运行,中国科学院上海应用物理研究所和上海市低温超导高频腔技术重点实验室共同研制了具备低高次模损失参数和可承受更高入射功率的新型500 MHz超导腔,作为上海光源在线运行超导高频腔的备用腔。超导铌腔经低温垂直测试达到所需加速性能后,需要与高功率输入耦合器、高次模吸收器、低温恒温器等集成并完成水平测试,获得超导腔模组的加速性能、低温性能和真空性能。介绍了超导腔备用腔的研制、集成和测试过程,采用文丘里(Venturi)校准法获得模组的静态功耗反应模组的低温性能,并通过高功率测试获得了超导腔备用腔模组的加速性能。测试结果表明:自主研制的500 MHz超导腔备用腔满足上海光源的工作需求,在超导腔的加速腔压为2.0 MV时,无载品质因数为1.2×109 @4.2 K,且低温模组的静态热损耗为36.1 W。Abstract: The Shanghai Synchrotron Radiation Facility (SSRF) is a third-generation synchrotron radiation source with an energy of 3.5 GeV. The superconducting radio frequency cavities have been used to compensate the energy dissipation during synchrotron radiation. A 500 MHz superconducting niobium cavity which adopts the one side fluted beam pipe for higher order modes propagation has been developed to provide support for the operation of SSRF. To make sure this superconducting cavity can be used as a substitution in SSRF, it is necessary to complete the horizontal test after the vertical test was completed successfully. The cavity have been assembled into the cryogenic module with high-power input couplers, high-order mode absorbers, etc.This paper presents the development and installation process of horizontal test module. The high power test of the superconducting cavity have been performed and the static heat loss of the superconducting cavity cryogenic module have been calculated by Venturi tube calibration method. The results show that the performance of 500 MHz superconducting cavity developed by Shanghai Institute of Applied Physics exceeds the working needs of SSRF. When the cavity accelerating voltage of the superconducting cavity is up to 2 MV, the unloaded quality factor Q0 is 1.2×109 at 4.2 K, and the static loss power of the cryogenic module is 36.1 W. The horizontal test for the 500MHz superconducting cavity have been completed in Shanghai Institute of Applied Physics (SINAP).
-
表 1 备用腔模组的主要参数表
Table 1. Main parameters of 500 MHz SRF cavity
voltage/MV Q0 Qe static loss power/W tuning range/MHz tuning sensitive/ (kHz·mm-1) 2.1 1.2×109@2MV 4.33×105 36.1 1.2 240 -
[1] Jiang Bocheng, Liu Guimin, Zhao Zhentang, et al. Simulation of a transverse feedback system for the SSRF storage ring[J]. High Energy Physics and Nuclear Physics, 2007, 31(10): 956-961. [2] Zhao Yubin, Yin Chengke, Zhang Tongxuan, et al. Digital prototype of LLRF system for SSRF[J]. Chinese Physics C, 2008, 32(9): 758. doi: 10.1088/1674-1137/32/9/015 [3] Padamsee H, Knobloch J, Hays T, et al. RF superconductivity for accelerators[M]. New York: John Wiley, 1998. [4] Liu Jianfei, Hou Hongtao, Miao Dongqing, et al. Great progress in developing 500 MHz single cell superconducting cavity in China[J]. Science China Physics, Mechanics and Astronomy, 2011, 54(2): 169-173. [5] Huang Tongming, Pan Weimin, Ma Qiang, et al. High power input coupler development for BEPCⅡ 500 MHz superconducting cavity[J]. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2010, 623(3): 895-902. doi: 10.1016/j.nima.2010.08.108 [6] Mi Zhenghui, Sun Yi, Wang Guangwei, et al. Horizontal test for BEPCⅡ 500 MHz spare cavity[J]. Chinese Physics C, 2012, 36(10): 996. doi: 10.1088/1674-1137/36/10/014 [7] 米正辉, 沙鹏, 孙毅, 等. BEPCⅡ国产500 MHz超导腔运行综述[J]. 强激光与粒子束, 2018, 30: 085103. doi: 10.11884/HPLPB201830.170485Mi Zhenghui, Sha Peng, Sun Yi, et al. Operation of domestic 500 MHz cavity. High Power Laser and Particle Beams, 2018, 30: 085103 doi: 10.11884/HPLPB201830.170485 [8] Ma Guangming, Liu Jianfei, Hou Hongtao, et al. Venturi tube application in high power test of the SRF module[J]. Nuclear Science and Techniques, 2009, 20(3): 129-132. [9] 张娟, 戴建枰, 黄泓, 等. 基于Labview的超导腔测试数据采集系统[J]. 核电子学与探测技术, 2013, 33(9): 1098-1103. https://www.cnki.com.cn/Article/CJFDTOTAL-HERE201309014.htmZhang Juan, Dai Jianping, Huang Hong, et al. Data acquisition system of superconducting cavity test based on Labview. Nuclear Electronics & Detection, 2013, 33(9): 1098-1103 https://www.cnki.com.cn/Article/CJFDTOTAL-HERE201309014.htm [10] 常玮, 何源, 李春龙, 等. 锁相环在超导射频技术中的应用[J]. 原子核物理评论, 2014, 31(2): 152-155. https://www.cnki.com.cn/Article/CJFDTOTAL-HWDT201402006.htmChang Wei, He Yuan, Li Chunlong, et al. Application of phase lock loop in superconducting RF technology. Nuclear Physics Review, 2014, 31(2): 152-155 https://www.cnki.com.cn/Article/CJFDTOTAL-HWDT201402006.htm