This paper uses both experimental and numerical approaches to revisit the concept of current transfer length (CTL) in second-generation high-temperature superconductor coated conductors with a current flow diverter (CFD) architecture. The CFD architecture has been implemented on eight commercial coated conductor samples from THEVA. In order to measure the 2D current distribution in the silver stabilizer layer of the samples, we first used a custom-made array of 120 voltage taps to measure the surface potential distribution. Then, the so-called ‘static’ CTL () was extracted using a semi-analytical model that fitted well the experimental data. As defined in this paper, the static CTL on a 2D domain is a generalization of the definition commonly used in literature. In addition, we used a 3D finite element model to simulate the normal zone (NZ) propagation in our CFD samples, in order to quantify their ‘dynamic’ CTL (), a new concept introduced in this paper and defined as the CTL observed during the propagation of a quenched region. The results show that, for a CFD architecture, is always larger than , whereas when the interfacial resistance between the stabilizer and the superconductor layers is the same everywhere. We proved that the cause of these different behaviors is related to the shape of the NZ, which is curved for the CFD architecture, and rectangular otherwise. Finally, we showed that the normal zone propagation velocity (NZPV) is proportional to , not with , which suggests that the dynamic CTL is the most general definition of the CTL and should always be used when current crowding and non-uniform heat generation occurs around a NZ.

本文使用实验和数值方法来重新审视具有电流分流器 (CFD) 架构的第二代高温超导体涂层导体中电流传输长度 (CTL) 的概念。CFD 架构已在来自 THEVA 的八个商用涂层导体样品上实施。为了测量样品银稳定剂层中的二维电流分布，我们首先使用定制的 120 个电压抽头阵列来测量表面电位分布。然后，所谓的“静态”CTL（) 是使用与实验数据拟合良好的半分析模型提取的。正如本文所定义的，二维域上的静态 CTL 是对文献中常用定义的概括。此外，我们使用 3D 有限元模型来模拟 CFD 样本中的法向区 (N​​Z) 传播，以量化它们的“动态”CTL ( )，这是本文引入的一个新概念，定义为在测量过程中观察到的 CTL淬灭区域的传播。结果表明，对于 CFD 架构，总是大于，而当稳定剂和超导体层之间的界面电阻处处相同时。我们证明了这些不同行为的原因与 NZ 的形状有关，NZ 的形状对于 CFD 架构是弯曲的，否则为矩形。最后，我们发现，正常区传播速度（NZPV）正比于，不与，这表明动态CTL为CTL的最一般的定义，并且当电流拥挤和不均匀的发热发生围绕应始终使用新西兰。