High temperature superconductor joins

High-temperature superconductor (HTS) joint characteristics are different from low-temperature superconductor (LTS) joint characteristics due to the anisotropy of HTS current density. The critical state model can be satisfied in LTS joints along most of the interface region for all possible current transfer distributions. A critical state model is assumed for the HTS in which the current density has different critical values in the transverse direction, along the c-axis, and in the longitudinal directions, in the a-b plane: and losses are generated in the superconductor at currents lower than the critical current. A two-dimensional model is used throughout the analysis. It is shown that superconductor losses are likely to be generated in the lead joint for HTS conductors in the case of low J/sub cr/. This is due to limiting of the J/sub r/ to its critical value. This is not the case for an LTS conductor, since J/sub r/ is limited only by J/sub c/. For lap joints, the cross-sectional area for J/sub r/ flow does not change, and large superconductor losses will be generated only if the average interface current is greater than J/sub ct/.