高温超导线圈的临界电流和交流损耗是衡量电气性能的主要参量。其中，感生磁场中的磁通线会受到钉扎势的作用，产生电磁能量损耗，即交流损耗。高温超导线圈的交流损耗所产生的热负荷不仅会增加运行成本，还会使高温超导线圈的局部温度升高。当高温超导线圈中同时存在交流背景磁场和交流传输电流时，其电磁特性更加复杂。为明确不同运行工况下高温超导线圈电气性能的影响因素和变化规律，本课题以REBCO(REBa₂Cu₃O_x，RE=Y，Gd等稀土元素)高温超导线圈为研究对象，对高温超导线圈的临界电流、交流损耗和载流特性进行研究分析。

首先，结合当前的研究现状和实际的工程需求，针对不同运行工况下高温超导线圈电气特性的影响因素展开了详细分析，总结了REBCO高温超导带材的基本结构与特性。基于高温超导带材临界电流特性的自洽模型，得到了一个评估高温超导线圈的临界电流的稳态模型，进而构建了REBCO高温超导线圈临界电流的仿真模型，获得了高温超导线圈的临界电流值。

其次，以圆形高温超导线圈为研究对象，基于H公式，构建了二维轴对称下高温超导线圈的多层数值模型。针对四种最典型的传输电流波形：正弦波、方波、锯齿波和三角波，研究了传输电流波形及幅值对传输损耗的影响。通过改变线圈的三种典型结构参数：线圈匝数、线圈半径和线圈匝间间距，得到了线圈的三种结构参数与传输损耗的依赖性关系。基于高温超导线圈的二维轴对称下多层数值模型，构建了高温超导线圈的三种典型运行工况，通过改变线圈匝数，得到了高温超导线圈被磁场穿透的范围大小以及交流损耗的变化规律。

最后，阐述了高温超导线圈接头处的带材连接方式和绝缘形式以及线圈设计参数，搭建了高温超导线圈的临界电流和交流损耗的实验平台。通过对比临界电流和传输损耗的仿真计算值与实验测试值，验证了高温超导线圈仿真模型的合理性与准确性。总结高温超导线圈的电气性能，为线圈的工程实现及其电气性能的深入研究提供了一定的参考依据。

The critical current and AC loss of high temperature superconducting (HTS) coil are the main parameters to measure the electrical performance. The magnetic flux lines in the induced magnetic field will be affected by the pinning force, resulting in electromagnetic energy loss, that is, AC loss. The thermal load caused by AC loss of HTS coil will not only increase the cost of operation, but also increase the local temperature of HTS coil. The electromagnetic characteristics of HTS coil are more complicated when there are both AC background magnetic field and AC transmission current. The critical current, AC loss and current-carrying characteristics of the REBCO ( REBa₂Cu₃O_x, RE=Y, Gd, and other rare earth elements) HTS coil are studied in this paper to clarify the influencing factors and changing rules of the electrical performance of the HTS coil under different operating conditions.

Firstly, in combination with the current state of research and actual technical requirements, the factors affecting the electrical characteristics of HTS coils under different operating conditions are analyzed in detail. In addition, the base structure and features of the REBCO HTS tape are summarized. A steady-state model for evaluating the critical current of HTS coil is introduced based on the self-consistent model of the critical current characteristics of HTS tape. Then, a simulation model of the critical current of REBCO HTS coil is constructed to obtain the critical current value of HTS coil.

Secondly, on the basis of the H formulation, a multilayer HTS circular coil numerical model with two-dimensional axial symmetry is constructed. The influence of the transmission current amplitude and waveform on the transmission loss is studied for four typical transmission current waveforms: sinusoidal wave, square wave, sawtooth wave and triangular wave. The dependence of three typical structural parameters of the coil on transmission loss is analyzed in detail by changing the coil radius, the number of coil turns and the inter-turn spacing of coil. Three typical operating conditions of the HTS coil are built on the basis of the two-dimensional axisymmetrical multi-layered numerical model of the HTS coil. By changing the number of coil turns, the range of HTS coil penetrated by magnetic field and the variation law of AC loss are analyzed.

Finally, the tape connection mode, the insulation form and the coil design parameters at the junction of the HTS coil are expounded. The experimental platform for critical current and AC loss of HTS coil is built. The rationality and accuracy of the simulation model of HTS coil are verified by comparing the simulated values of critical current and transmission loss with the experimental values. The electrical properties of HTS coil are summarized, which provides some reference for the engineering realization of coil and the in-depth study of its electrical properties.

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