Numerical investigation of current distributions around defects in high temperature superconducting CORC® cables

Abstract

High performance ReBCO magnet prototypes are typically monitored and protected with voltage measurements, however a variance in safe operating limits has been observed. A potential issue arises from current redistribution phenomena associated with unidentified defects in cables composed of ReBCO tapes. In this work, a network model is developed to simulate current and voltage distributions around defects in CORC® cables. The evolving network of conductor overlap is evaluated. Trends in CORC® operation at 77 K are presented, and it is shown that power dissipation in an I–V curve depends strongly on a third dimension of defect magnitude. The predictive tool is then coupled with a differential evolution algorithm to recommend optimal CORC® layering topologies based on reel-to-reel tape measurements. The developed model facilitates understanding of CORC® cable phenomena, and the results suggest high temperature superconducting magnet protection can be improved with cable and defect characterization efforts.