Numerical Simulation of Contactless Methods for Measuring <i>j</i>_Cin High-Temperature Superconducting Film: Influence of Defect on Resolution and Accuracy

Abstract

The inductive method for measuring the critical current density in a high-temperature superconducting (HTS) film has been reproduced numerically. To this end, a numerical code has been developed for analyzing the time evolution of a shielding current density in an HTS film containing a crack. The of computational results show that the accuracy of the inductive method monotonously increases with the height of the coil. In addition, the accuracy is slightly improved by changing the inner radius of the coil, and there exists the optimum inner radius. Although the accuracy is degraded due to the crack, this result means that the inductive method can be applied to the crack detection. Consequently, the crack located near the film edge cannot be detected with high accuracy because the crack is treated the same as the film edge.