聚变高温超导D型磁体和环形磁场线圈机械稳定性分析

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聚变高温超导D型磁体和环形磁场线圈机械稳定性分析

刘羽涵，王银顺^*

华北电力大学电气与电子工程学院，北京市昌平区 102206

基金资助:
国家自然科学基金项目(52377024)

Mechanical Stability Analysis of High-Temperature Superconducting D-Shaped Magnets and Toroidal Field Coils for Fusion

LIU Yuhan, WANG Yinshun^*

School of Electrical and Electronic Engineering, North China Electric Power University, Changping District, Beijing 102206, China

Supported by:
National Natural Science Foundation of China (52377024)

摘要/Abstract

摘要： 【目的】高温超导(high temperature superconducting，HTS)D型线圈是核聚变装置中的核心部件之一，其运行电流大、磁场高，产生的洛伦兹力大，对磁体的稳定运行具有重要影响。为此，对采用基于圆芯管内电缆导体(conductor on round core cable-in-conduit conductor，CORC CICC)的D型磁体和环形磁场(toroidal field，TF)线圈在20 K温度下的机械稳定性进行了研究。【方法】首先，建立并分析线圈三维有限元模型，得到其单位体积的力在D型磁体弯曲处、TF线圈中心段最大，分别为1.74×10⁸ N/m³和2.24×10⁸ N/m³；接着，分析磁体三维力热耦合模型，针对磁体不同位置的机械稳定性进行研究，对其失超能及失超传播速度进行了计算，得到在磁场最大位置的失超能与失超传播速度最大，其中失超能为1.03×106 J/m3，轴向和横向失超传播速度为142.86 mm/s和2.77 mm/s。最后，提出一种加入氮化铝(AlN)和环氧树脂混合材料的方法来提升磁体的机械稳定性。【结果】在磁场最大位置的最小失超能变大。添加混合材料后，轴向失超传播速度比不加时更慢，横向失超传播速度比不加时更快。【结论】D型磁体和TF线圈存在机械稳定性最薄弱部位，所提出的机械稳定性方法不仅可以有效提高磁体的机械稳定性，也对20 K温区大型超导磁体的设计和运行具有重要参考价值。

关键词: 高温超导(HTS), 圆芯管内电缆导体(CORC CICC), D型磁体, 环形磁场线圈, 机械稳定性, 失超, 氮化铝, 环氧树脂

Abstract: [Objectives]　The high-temperature superconducting (HTS) D-shaped coil is one of the core components in nuclear fusion devices. It features a large operating current, high magnetic field, and significant Lorentz force, which has a significant impact on the stable operation of the magnet. Therefore, an investigation is conducted on the mechanical stability of D-shaped magnets and toroidal field (TF) coils based on the conductor on round core cable-in-conduit conductor (CORC CICC) at 20 K. [Methods]　Firstly, a three-dimensional finite element model is established and analyzed, revealing that the force per unit volume reaches its maximum at the bend of the D-shaped magnets (1.74×10⁸ N/m³) and the central section of the TF coils (2.24×10⁸ N/m³). Next, the three-dimensional thermo-mechanical coupling model is analyzed, and the mechanical stability at different positions of the magnets is studied. The quench energy and quench propagation velocity of the magnets are calculated, and it is found that both attain their highest values at the maximum magnetic field position, with quench energy measured at 1.03×10⁶ J/m3, and the axial and transverse quench propagation velocities at 142.86 mm/s and 2.77 mm/s, respectively. Finally, a method of incorporating AlN and epoxy hybrid material is proposed to improve the mechanical stability of magnets. [Results]　The minimum quench energy at the maximum magnetic field position increases. The axial quench propagation velocity is slower than that without the hybrid material, while the transverse velocity is faster than that without the hybrid material. [Conclusions]　The D-shaped magnets and the TF coils have the weakest mechanical stability points. The proposed mechanical stability method can not only effectively improve the mechanical stability of magnets, but also has significant reference value for the design and operation of large superconducting magnets operating in the 20 K temperature range.

Key words: high-temperature superconducting (HTS), conductor-on-round-core cable-in-conduit conductor (CORC CICC), D-shaped magnet, toroidal field (TF) coils, mechanical stability, quench, aluminum nitride, epoxy resin

刘羽涵, 王银顺. 聚变高温超导D型磁体和环形磁场线圈机械稳定性分析[J]. 发电技术.

LIU Yuhan, WANG Yinshun. Mechanical Stability Analysis of High-Temperature Superconducting D-Shaped Magnets and Toroidal Field Coils for Fusion[J]. Power Generation Technology.