High normal zone propagation velocity in copper-stabilized 2G HTS coated conductors

Copper-stabilized second generation high-temperature superconductor (HTS) coated conductors were modified to enhance their normal zone propagation velocity (NZPV). Experimental results, supported by numerical simulations, indicate that adding copper on the substrate side instead of adding it on the HTS side increases the NZPV by a factor of 2-3. Furthermore, a novel tape architecture, called hybrid-current flow diverter (CFD), was investigated. This hybrid-CFD tape was designed with the goal of having a very long current transfer length, which is the key to enhance the NZPV. Results show that it is possible to fabricate an HTS tape with double stabilizer thickness in comparison to a bare tape, while accelerating the NZPV by a factor of three. With the same approach, a ten-fold increase of the NZPV can be expected for a tape with a 40 mu m thick copper-stabilizer.