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Within a German government funded project with the partners Siemens and KIT, we present the concept and first results for a full-scale inductive superconducting fault current limiter. It is based on the well-known shielded core concept but does not need the deployment of an iron core. Aim of the project is the construction and test of one phase with a nominal current I = 600 A and a voltage of U = 10 kV, i.e., a protected power of P = 10 MVA for the three-phase system. The shielding is provided by a stack of superconducting rings, i.e., YBCO-tapes soldered to closed rings, with a radius of R = 0.7 m. To obtain a sufficient coupling between the reactor (primary coil, warm) and the shielding stack, the minimization of the gap between both is crucial. The paper presents numerical work with respect to the overall geometry and the physical properties (limitation behavior, ac-losses) of the device. Also a suitable superconducting material had to be qualified. Finally, a test equipment for single components (rings) was built up and successful tests of first superconducting full size components are reported. [ABSTRACT FROM PUBLISHER]

High temperature superconductor Roebel cables are well known for their large current capacity and low AC losses. For this reason they have become attractive candidates for many power applications. The continuous transposition of their strands reduces the coupling losses while ensuring better current sharing among them. However, since Roebel cables have a true 3D structure and are made of several high aspect ratio coated conductors, modelling and simulation of their electromagnetic properties is very challenging. Therefore, a realistic model taking into account the actual layout of the cable is unavoidably a large scale computational problem. In this work, we present a full 3D model of a Roebel cable with 14 strands. The model is based on the H-formulation, widely used for 2D problems. In order to keep the 3D features of the cable (in particular the magnetization currents near the transpositions), no simplifications are made other than the reduction of the modelled length according to the periodicity of the cable structure. The 3D model is used to study the dependence of AC losses on the amplitude of the AC applied magnetic field or transport current. Beyond the importance of simulating the Roebel cable layout, this work represents a further step into achieving 3D simulation of superconducting devices for real applications. [ABSTRACT FROM AUTHOR]