September 21, 2018 (STH60, HP135).  We report on recent advances in MOCVD growth of REBCO films with a very high thickness that have overcome this issue, demonstrated by achieving record in-field high engineering current densities (J_e) over all competing superconductor technologies and over a wide range of temperatures and fields. In this highlight, we focus on the record high in-field J_e at 4.2K of >4 µm thick Zr-doped REBCO films [1]. These results have been achieved by using an Advanced Metal Organic Chemical Vapor Deposition (A-MOCVD) system, which has been specifically developed to overcome the issue of J_c deterioration with thickness. The remarkably high J_e values achieved over a wide range of applied fields at 4.2K clearly demonstrate the strong potential of REBCO coated conductors for high-field magnet application.

Fig. 1.  Engineering current density vs. field of thick UH REBCO tape and other technical superconductors at 4.2 K [3].

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June 8, 2018 (STH57, HP132).  The study of the electromagnetic-thermal phenomena of superconducting fault current limiters operating in electrical grids is often neglected in transient simulations due to extensive simulation times or unavailability of commercial software easily addressing the coupling between electromagnetic and thermal phenomena [1, 2]. Recently, in [3], we have presented a fast simulation methodology to predict the dynamical electromagnetic-thermal behavior of an inductive-type limiter, namely: line current, primary linked flux as well as temperature and current in superconducting secondary. Simulations have been compared to experimental results from a laboratory scale prototype, depicted in Fig. 1 [3, 4].

Fig. 1.  Laboratory scale prototype (dimensions in millimeters) [3].

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