An Experimental Investigation of Critical Current and Current Distribution Behavior of Parallel Placed HTS Tapes

The AC superconducting power transmission cable projects are being carried out around the world, while the DC superconducting cable is also proven to be very competitive for power transmission in electrical grid due to the negligible AC losses. The critical current and current distributions are two important factors to improve the performance of DC HTS cable for large transmission capacity. In this paper, we proposed an experimental method to investigate the behavior of critical current affected by various gap distances between the individual HTS tape and transverse tape width. The results show that the critical current of the HTS tape in the cable field can be increased by about 10% if the gap distance is less than 1 mm. Finite element method (FEM) is used to calculate the magnetic field distribution to verify the experimental results. A short HTS cable has been constructed to investigate the influence of contact resistance on the current distribution among the HTS tapes. The results show that the contact resistances have significant influence on the current sharing of each HTS wire in the cable structure.