Estimation of the Critical Current Density From the Measured Values of Perpendicular Magnetization Losses in HTS Coated Conductors

Abstract

Stacking of conductors for large current capacity and striation for low loss are needed in large scale power applications of HTS superconductor. It, however, was difficult to measure superconducting properties of the HTS coated conductor non-destructively. Instead of direct measurement of the critical current of HTS coated conductor, indirect estimation from the measured magnetization loss can be used for the practical estimation of the critical current. The magnetization loss of a superconductor can be affected by the full penetrating magnetic field, and it tends to show an inflection point at the full penetrating magnetic field in the plot of magnetization loss vs. external magnetic field. The full penetrating magnetic field depends on the shape of the conductor and its critical current density, and so the effective critical current density can be estimated from the measured magnetization loss. In this paper, to prove the effectiveness of this indirect estimation of the critical current, we measured the perpendicular magnetization losses in short samples of 2G HTS coated conductors with different shapes which includes striated coated conductors were measured, and the estimated critical current densities were compared with those directly measured.