Novel Defect Tolerant HTS Conductor for Coil Applications

The U.S. Navy is actively developing new High Temperature Superconducting (HTS) technologies to support its all-electric ship program. The HTS technologies being investigated by the Navy include power distribution cables, DeGaussing cables, (HTS-DG), unmanned Mine Sweeping (HTS-MS), motors/generators, and Superconducting Magnetic Energy Storage (SMES).For any of these HTS based systems, there is always a potential risk of HTS conductor quench, resulting in complete system failure as well as irreversible and irreparable damage to the HTS conductor. To address this serious issue, the Navy is desirous of a Defect Tolerant HTS (DT-HTS) conductor capable of continued operation through a partial quench, thereby enabling a Quench Detection and Quench Protect (QD/QP) system to engage and discharge the HTS coil safely. Since QD/QP systems are currently being developed under a separate Navy SBIR program, solutions must be geared towards the HTS conductor itself and not the HTS coil winding. In addition, DT-HTS conductor solutions must retain all aspects of high performance HTS wire/tape and operate with engineering current densities (Je) > 200 A/mm2 at operating temperatures between Top ~30-50 K and background magnetic fields Bop ~1-3 Tesla (T). The HTS wire/tape architecture should also utilize conventional substrates (e.g., hastelloy™ C276, Ni-W SS, etc.), accommodate laminated structures (e.g., brass, Cu, SS), and possess tape dimensions between (3à12 mm width), typically used in Naval HTS device applications. Energy to Power Solutions (e2P), in collaboration with Dr. Sastry Pamidi of the Florida State University Center for Advanced Power Systems (FSU-CAPS), proposes to design, fabricate, and cryogenically test a robust, reliable, and low-cost DT-HTS conductor for coil applications. Our proposed DT-HTS conductor is based on e2P’s proprietary and proven HTS conductor technology. Unlike current State-of-the-Art HTS tape technologies that are highly susceptible to localized defects and, in some circumstances, have resulted in catastrophic quenches and irreparable damage to HTS SMES systems, e2P’s proposed conductor technology provides a novel solution to overcoming defects without damaging the HTS conductor. e2P’s conductor technology has already proven extremely effective in HTS coils wound with 4-mm wide 2G REBCO tape fabricated by SuperPower. During the proposed Navy Phase I STTR effort, e2P and FSU-CAPS will investigate alternate 2G REBCO wire manufacturers from AMSC and additional conductor widths up to 12 mm, such as those used by AMSC in HTS MS applications. In addition, e2P has formulated a test evaluation methodology to evaluate the efficacy of our proposed DT-HTS conductor using our proprietary technology. If successful, our proposed test methodology should be able to be extended from simple straight tape sections in the Phase I-Base effort to more representative HTS coils in the Phase I-Option.