This paper reports the magnetic field and winding force-dependent contact resistance, also known as characteristic resistance, of no-insulation (NI) REBCO coil. Three NI coils were wound with different winding forces ( < 1 kgf, 3 kgf, and 5 kgf) using the same REBCO-coated conductor, and they were tested at 4.2 K in a background field of 0, 5, 10, and 14 T. The contact resistance of each coil is measured at each field. As a result of the measurements, we draw two conclusions. First, a quadratic function for magnetic field intensity reasonably reproduces the measurement results of each NI test coil’s magnetic field-dependent contact resistance, where the practical fit function’s coefficients are determined depending on the winding force. Second, the contact resistance of each coil is partially inconsistent with the magnetoresistance of the electroplated material, i.e. copper, of the REBCO-coated conductor. This paper will present the measurement results in detail, discuss them with Kohler’s rule, and formulate the contact resistance using winding force and magnetic field terms.

中文翻译：

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研究 NI REBCO 线圈的磁场和缠绕力相关接触电阻的实验研究

本文报告了非绝缘 (NI) REBCO 线圈的与磁场和缠绕力相关的接触电阻（也称为特征电阻）。三个 NI 线圈以不同的绕线力绕制（ < 1 kgf、3 kgf 和 5 kgf）使用相同的 REBCO 涂层导体，并在 0、5、10 和 14 T 的背景场中在 4.2 K 下进行测试。在每个线圈处测量每个线圈的接触电阻。场地。根据测量结果，我们得出两个结论。首先，磁场强度的二次函数合理地再现了每个 NI 测试线圈的磁场相关接触电阻的测量结果，其中实际拟合函数的系数根据缠绕力确定。其次，每个线圈的接触电阻与REBCO涂层导体的电镀材料（即铜）的磁阻部分不一致。本文将详细介绍测量结果，并与科勒法则进行讨论，并使用绕组力和磁场项来公式化接触电阻。