Calculation and Optimization of ITER Upper VS Feeder Under an Electromagnetic Load

The upper vertical stability （VS） feeder is a part connected to the upper VS coil by a welding joint. The function of the feeder is to transfer current and coolant water to the VS coil. A giant electron^agnetic force will be generated during normal operation by the current flowing in the VS coils, interacting with the external background field. The Lorentz force will induce Tresca stress in the feeder. The amplitudes of the magnetic field and Lorentz force along the conductor running direction have been calculated based on Maxwell＇s equations. To extract the Tresca stress in the feeder, a finite element model was created using the software ANSYS and an electromagnetic load was applied on the model. According to the analytical design, the stresses were classified and evaluated based on ASME. In order to reduce the Tresca stress, some optimization works have been done and the Tresca stress has had a significant reduction in the optimized model. This analytical work figured out the stress distribution in the feeder and checked the feasibility of the prototype design model. The ANSYS analysis results will provide a guidance for later improvement and fabrication.

ITER Magnet Feeder:Design,Manufacturing and Integration

The International Thermonuclear Experimental Reactor （ITER） feeder procurement is now well underway. The feeder design has been improved by the feeder teams at the ITER Organization （IO） and the Institute of Plasma Physics, Chinese Academy of Sciences （ASIPP） in the last 2 years along with analyses and qualification activities. The feeder design is being progressively finalized. In addition, the preparation of qualification and manufacturing are well scheduled at ASIPP. This paper mainly presents the design, the overview of manufacturing and the status of integration on the ITER magnet feeders.

Primary Design and Analysis of Feeder for ITER Poloidal Field

An electromagnetic （EM） analytic model for the PF feeder, applied to ITER and needed to convey the cryogenic supply and electrical power to the PF magnets, was built up. The magnetic flux density and the EM force under the worst conditions with the maximum working current in each coil were then calculated. Based on the EM analysis and theoretical calculation, the relationship between the busbar stress and the distance of neighbouring busbar supports was obtained, which provides an approach to optimize the design of the busbar supports. In order to check the feasibility of the PF feeder structure, a finite element model was built up and the ANSYS code was applied to analyze the stress and displacement. The numerical results show that the stress of the PF feeder is within the allowable limits and the structure is feasible.

Evolution of the Design of Cold Mass Support for the ITER Magnet Feeder System

This paper presents the evolution of the design of cold mass support for the ITER magnet feeder system. The glass fibers in the cylinder and the flanges of the normal G10 support are discontinuous in the preliminary design. The heat load of this support from the analysis is only 4.86 W. However, the mechanical test of the prototype showed that it can only endure 9 kN lateral force, which is significantly less than the required 20 kN. So, the configuration of the glass fibers in the cylinders and flanges of this G10 support are modified by changing it to a continuous and knitted type to reinforce the support, and then a new improved prototype is manufactured and tested. It could endure 15＇kN lateral forces this time, but still not meet the required 20 kN. Finally, the SS316LN material is chosen for the cold mass supports. The analysis results show that it is safe under 20 kN lateral forces with the heat load increased to 14.8 W. Considering the practical application, the requirements of strength is of primary importance. So, this SS316LN cold mass support is acceptable for the ITER magnet feeder system. On the other hand, the design idea of using continuous and knitted glass fibers to reinforce the strength of a G10 support is a good reference for the case with a lower heat load and not too high Lorentz force.

Conceptual Design and Analysis of Cold Mass Support of the CS3U Feeder for the ITER

In the International Thermonuclear Experimental Reactor（ITER） project,the feeders are one of the most important and critical systems.To convey the power supply and the coolant for the central solenoid（CS） magnet,6 sets of CS feeders are employed,which consist mainly of an in-cryostat feeder（ICF）,a cryostat feed-through（CFT）,an S-bend box（SBB）,and a coil terminal box（CTB）.To compensate the displacements of the internal components of the CS feeders during operation,sliding cold mass supports consisting of a sled plate,a cylindrical support,a thermal shield,and an external ring are developed.To check the strength of the developed cold mass supports of the CS3U feeder,electromagnetic analysis of the two superconducting busbars is performed by using the CATIA V5 and ANSYS codes based on parametric technology.Furthermore, the thermal-structural coupling analysis is performed based on the obtained results,except for the stress concentration,and the max.stress intensity is lower than the allowable stress of the selected material.It is found that the conceptual design of the cold mass support can satisfy the required functions under the worst case of normal working conditions.All these performed activities will provide a firm technical basis for the engineering design and development of cold mass supports.

ITER过渡馈线直线段管的优化设计与屈曲分析

根据强度原则,用有限元静力分析方法优化了馈线系统直线段管中的圆管和波纹管相关结构的设计参数;根据能量准则,通过特征值屈曲分析和非线性屈曲分析方法,用有限元法稳定性的判据计算出长跨度的薄壳直线段管发生失稳时的临界载荷为1.21MPa,验证了该结构在正常工况(安全系数为12.1)和故障状态工况(安全系数为6.05)下不会发生失稳现象,为ITER馈线系统的下一步研制提供了基础。

ITER馈线S弯结构的应力分析和优化设计

根据能量方法原理,通过单位力法和卡氏定理分析方法,理论计算得出了给定位移变形条件下沿S弯的弯矩、应力分布。分析表明,沿S弯结构的应力主要由热收缩变形产生,但重力影响也不可忽略,考虑重力影响后沿S弯最大应力较不考虑重力时增大了10%。根据该理论原理编程计算发现,在S弯高度受限的条件下,圆弧段半径越小,结构最大应力越小,实际设计中可根据强度要求结合加工工艺选择合适的圆弧半径。该分析方法为有效优化结构设计提供了理论指导。

ITER磁体馈线系统焊接材料的电性能研究

在国际热核聚变实验堆(ITER)磁体馈线(Feeder)系统中,超导接头和电流引线中都需大量使用焊料对其进行焊接。为了避免相邻处接头在焊接时产生相互影响,必须保证各相邻接头间焊料熔点具有一定梯度。用几种不同焊料对焊接工艺以及接头测试装置进行了介绍。同时也对低温下超导接头的电性能进行了测试。对Bi-2223/Ag超导带材进行了焊接。结果表明,低熔点焊料Bi50Sn9Pb31和In99.99,高熔点焊料Sn96.5Ag3Cu0.5在低温下都具有较低的电阻,并满足温度梯度的使用要求。这对ITER Feeder系统在对焊接材料的测试以及选择上都将具有十分重要的参考价值。

ITER极向场内馈线的结构设计

根据ITER装置对极向场内馈线系统的性能要求,同时考虑该系统所处空间位置的复杂性和工作环境的特殊性,利用三维建模软件CATIA对极向场内馈线结构进行概念设计,为同类型超导磁体的馈线设计提供了有益的参考。

ITER TF线圈馈线系统地震动响应分析

对TF线圈馈线系统做了地震响应分析。利用ANSYS有限元软件对一个TF线圈馈线系统进行了模态分析与响应谱分析,得到了在地震载荷下的峰值响应(应力和位移)。最后,根据ITER磁体结构设计标准,对系统的最大Tresca应力进行了评估。结果表明,TF线圈馈线系统满足SC1抗震等级的要求。

基于迭代学习控制的投料机称重控制系统设计

由于现有沥青拌和站投料设备的称重控制系统加料精度不稳定,故无法适应不同类型的物料。利用OPC实现Matlab与PLC之间的通讯,突破了PLC编程语言的限制,将迭代学习控制算法应用在PLC中,采用PI型学习控制律,分析了不同增益参数对系统性能的影响。结果表明:将迭代学习控制算法应用在称重控制系统中,能明显降低投料误差,改善其鲁棒性。

智能电网馈线终端一种高精度测频算法及应用

介绍了应用于智能电网速动保护的馈线终端高精度测频算法的具体设计。首先,灵活改进了传统的傅里叶算法,以角长度0.2π为基准,计算基波信号1/10的相角差,同时,提出了迭代运算方法与均值最小化误差算法,设置在硬件上很容易实现的较低的固定采样频率4kHz,不受同步采样限制。无论是含有大量谐波及电网白噪声干扰的稳态电力信号,还是暂态电力信号,在频率、幅值突变情况下,与目前多种测频算法进行仿真比较,仿真与实验的结果证明,该算法精度高,计算量不大,在跟踪时间和超调误差方面具有明显的优越性,完全适合于智能电网配电自动化测控装置的实际应用。

线圈终端盒的改进设计与分析

为满足美国GA公司中心螺线管线圈模型CSM低温电性能测试的需要,基于ITER馈线系统的设计,对线圈终端盒壳体进行了修改设计。采用直立圆筒结构代替横卧立方体结构,优化了壳体安装工艺,提高了空间利用率。在此基础上,对线圈终端盒内部其他部件进行了相应的改进设计,最终实现了线圈终端盒的功能。利用大型有限元分析软件ANSYS对线圈终端盒壳体作弹性应力分析、屈曲分析及地震分析,并将屈曲分析结果与理论计算结果进行了对比。计算分析结果表明,直立圆筒结构形式的线圈终端盒设计合理可靠。

ITER磁体馈线导体不锈钢铠甲力学性能研究

ITER磁体馈线(Feeder)导体在生产过程中,要经过压缩成型。为了模拟导体的真实工况,铠甲力学测试样品在准备前都压缩到了导体要求的尺寸。文中测试了ITER磁体馈线导体在正式生产阶段不锈钢铠甲的常温与低温(<7K)力学性能,并进行了统计分析。

基于蚁群-遗传算法的贴片机喂料器分配优化研究

针对在元器件贴装顺序已知的前提下研究拱架式贴片机的喂料器在喂料槽上分配优化的问题,给出了以贴片头在喂料槽移动距离最小化为优化目标的喂料器分配优化模型.利用蚁群算法与遗传算法的混合算法实现对贴片机的喂料槽分配问题进行求解,将蚂蚁搜索的结果进行迭代交换、交叉和变异.为了验证算法有效性,以20块实际生产的PCB为实例进行了测试.与遗传算法相比,所提出算法的平均效率提高了4.48%.