High-current superconducting conductors are widely used in fusion magnets and high energy accelerators. In order to carry out experimental research on new high-current conductors, we have developed a new test facility for their critical current (I_c) measurements. We have used this facility to test a Nb-Ti Rutherford cable three times. Premature quenches were detected for the first two tests. They were mainly caused by small mechanical motion of the cable sample. After the mechanical support enhancement of sample, the critical current was successfully measured at the third time. The fixing structures of sample for these three tests are described and compared in consideration of transverse pressure applied to sample during different stages and the transverse displacement of cable after powering. The transverse pressure of first two tests reduced after cooling down and were not strong enough to withstand Lorentz force. Assuming uniform current distribution among strands and considering the inhomogeneous self-field, a model is developed to predict the V-I characteristics of the Rutherford cable using the measured properties of the strand. The expected I_c of cable under different background magnetic field are consistent with the measured results.

大电流超导导体广泛用于聚变磁体和高能加速器中。为了对新型大电流导体进行实验研究，我们针对其临界电流（I _c） 测量。我们已经使用此工具对Nb-Ti Rutherford电缆进行了三遍测试。在前两个测试中检测到过早的淬火。它们主要是由电缆样本的较小机械运动引起的。样品的机械支撑增强后，第三次成功测量了临界电流。描述并比较了这三个测试中样品的固定结构，并考虑了不同阶段施加在样品上的横向压力以及通电后电缆的横向位移。冷却后，前两次测试的横向压力降低，强度不足以承受洛伦兹力。假设各股之间的电流分布均匀，并考虑不均匀的自电场，开发了一个模型，以使用测得的绞线特性预测卢瑟福电缆的VI特性。预期的电缆在不同背景磁场下的I _c与测量结果一致。