Numerical investigation on scanning permanent magnet method: influence of crack on resolution and accuracy

The scanning permanent magnet method for measuring the critical current density in a high-temperature superconduct-ing (HTS) tape has been simulated numerically. To this end, a numerical code has been developed for analyzing the timeevolutionofa shielding currentdensityinanHTStapewitha crack.The resultsof computationsshowthatthetwo peaks of the electromagnetic force is monitored near the crack even if the crack size is small. This means that the crack position and size can be estimated by using the scanning method. We conclude that the crack cannot be detected near the length and width directions of the tape edge because the two peaks of the electromagnetic force hardly appear.