Development of rotating coil measurement system for China Spallation Neutron Source
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摘要: 中国散裂中子源(CSNS)加速器主要由一台直线加速器、一台快循环加速器以及低能、高能输运线组成。针对CSNS加速器部分直流磁铁研制了一套旋转线圈测量系统。对系统的研制方案、功能、精度、完成的磁铁类型以及部分测量结果进行介绍。该系统解决了CSNS批量磁铁之间的不同中心高度、质量、有效长度、磁场强度的兼容性难题。经过测试运行,积分场测量重复性误差好于±0.02%,空间谐波重复性误差好于0.005%,磁中心测量重复性误差好于±0.03 mm,顺利完成了中国散裂中子源工程150台多种类型磁铁的检测任务。Abstract: The China Spallation Neutron Source (CSNS) accelerator mainly consists of a linear accelerator, a 1.6 GeV rapid cycling synchrotron (RCS), a low energy transport line and a high energy transport line. A rotating coil measurement system was developed for the DC magnets of the CSNS accelerator. This system solves the compatibility problems of different center heights, masses, effective lengths, and magnetic field strengths among CSNS bulk magnets. After testing, the repeatability error of the integral field measurement is less than ±0.02%, the repeatability error of harmonics is less than 0.005%, the repeatability error of the magnetic center measurement is less than ±0.03mm. It has successfully completed the task of detecting 150 magnets of the China Spallation Neutron Source. In this paper, the development plan, function, accuracy, types of measured magnets and some measurement results are introduced.
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Key words:
- rotating coil /
- magnetic field measurement /
- corrector magnet /
- quadrupole magnet /
- sextupole magnet
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表 1 CSNS部分直流多极磁铁参数
Table 1. Parameters of partial DC multipole magnet for CSNS
magnet type quantity gradient aperture/mm good field region/mm effective length/mm field error/% total weight/kg LR-80Q 37 4.7 T·m-1 80 70 200 ±0.1 300 LR-120Q 10 4.7 T·m-1 120 110 200 ±0.1 450 RCS-230S 16 40.0 T·m-2 230 218 200 ±0.5 859 RT-180QA 19 7.0 T·m-1 180 160 500 ±0.1 1900 RT-180QB 2 6.1 T·m-1 180 160 500 ±0.1 1700 表 2 CSNS部分校正磁铁参数
Table 2. Parameters of corrector magnet for CSNS
magnet type quantity central magnetic field B0/T effective length/m integral field/(T·m) aperture(W×H) width of good field/mm field uniformity/% total weight/kg LR-80CH 8 0.01 0.2 0.002 80 mm×80 mm 70 ±0.1 35 RCS-300CH 17 — — 0.008 300 mm×300 mm 192 ±0.1 186 RT-180CV 5 0.04 0.2 0.008 180 mm×180 mm 153 ±0.1 144 RT-206CV 4 0.04 0.2 0.008 206 mm×206 mm 175 ±0.1 168 表 3 r0/r1不同比值导致的误差因子
Table 3. Error factor caused by different ratios of r0/r1
n (r0/r1)n-2 r0/r1=0.8 r0/r1=0.9 r0/r1=1 r0/r1=1.2 r0/r1=1.5 3 0.80 0.90 1 1.20 1.50 4 0.64 0.81 1 1.44 2.25 5 0.51 0.73 1 1.73 3.38 6 0.41 0.66 1 2.07 5.06 7 0.33 0.59 1 2.49 7.59 8 0.26 0.53 1 2.99 11.39 9 0.21 0.48 1 3.58 17.09 10 0.17 0.43 1 4.30 25.63 11 0.13 0.39 1 5.16 38.44 12 0.11 0.35 1 6.19 57.67 13 0.09 0.31 1 7.43 86.50 14 0.07 0.28 1 8.92 129.75 表 4 径向线圈设计参数
Table 4. Design parameters of radial coil
coil number magnet type r1/mm r2/mm r3/mm r4/mm outer coil/turns inner coil/turns skeleton length/mm A LR-80Q, LR-120Q, LR-80CH/V 36 25.5 27 16.5 280 420 750 B RT-180QA/B, RT-180CH/V, RT-206CH/V 76.5 54.18 57.38 35.06 120 180 1300 C RCS-230S, RCS-300CH/V 102 79.59 81.6 66.8 160 320 1300 表 5 梯度积分场和磁中心偏置
Table 5. Gradient integral field and magnetic center offset
content gradient integral field GL/T Dx/mm Dy/mm Dr/mm 2014.09.22PM 1.059 51 0.09 -0.02 0.09 2014.09.23AM 1.059 45 0.07 -0.02 0.07 -
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