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In the framework of the development of High Temperature Superconducting (HTS)-based solutions for modern power grids, Ricerca sul Sistema Energetico - RSE S.p.A. has gained a significant experience in design, testing, and installation of superconducting fault current limiters (SFCLs). After having successfully demonstrated the techno-economic feasibility of the first Italian three-phase BSCCO-based SFCL (9 kV/3.4 MVA) inside the distribution grid of A2A Reti Elettriche S.p.A. in the Milano area, RSE has initiated the development of a new upgraded three-phase SFCL, whose rated power has been enhanced in order to meet the utility's needs. Unlike the first prototype, the new SFCL device (9 kV/15.6 MVA) is YBCO-based: this choice allows reducing the needed tape length and cooling power, saving at the same time a significant amount of operational costs. The first phase was already assembled and tested in 2015, whereas the second phase was tested in February 2016. This paper will show the last outcomes from characterizations and short-circuit tests. Along with the SFCL project, RSE has also been focusing on superconducting cables and, in the framework of the European Project Best Paths, it has been involved in DEMO5, that is dedicated to the development of a HTS DC cable in MgB2 (10 kA/3.2GW). Taking the cue from the DEMO5 requirements, RSE has initiated a parallel research activity that is focused on studying the thermo-fluid dynamic behavior of cryogenic coolants flowing in forced convection regime inside the flexible cryostat. This paper will present the first simulation results and will give some anticipation on next steps. [ABSTRACT FROM PUBLISHER]

A three-year research project, called DRYSMES 4GRID, was recently funded by the Italian Minister of Economic Development, Italy. The project, which involves five Italian partners (companies, universities, and research institutes), is aimed to demonstrate the feasibility of cost-competitive SMES based on magnesium diboride (MgB2 ) with a cryogen-free cooling bymeans of the manufacturing and the testing of a demonstrator with an objective rating of 500 kJ/200 kW. This rating is deemed suitable for disclosing the critical technological aspects of all components in view of practical applications. A further goal of the project is the assessment of the technical and economic benefits that the SMES can bring to real-world electric grids. The general outline and technical objectives of the project are presented in this paper. Preliminary design assumptions and results concerning the MgB2 coil and the power condition system are also discussed. [ABSTRACT FROM AUTHOR]

A novel energy storage system based on a SMES cooled by cryogenic fuel is being developed at the Dept. of Electrical Engineering of the University of Bologna. The system represents an alternative solution with respect to nowadays battery packs for the storage of electrical energy with large specific power. The device may find suitable application on board of road vehicles fed by liquid hydrogen with hybrid power-train (internal combustion engine and electric motor/generation), where a cryogenic tank is already present and no additional cryogenic costs are needed. The housing of the SMES inside the tank used for fuel storage, allows the exploitation of the thermal power required for the continuous evaporation of fuel for feeding the engine to remove the AC losses from the magnet, thus avoiding the need of externally supplied cooling power. In this paper both the design of the magnet and its operation in combination with electronic converter and electric motor/generator during charge/discharge cycles are discussed. Moreover the ongoing activity for the development of a laboratory-scale prototype using MgB2 superconductor is presented. [ABSTRACT FROM AUTHOR]

INFN (Istituto Nazionale di Fisica Nucleare, Italy) has started in 2006 the DISCORAP project, which foresees the design, manufacture and test of a dipole prototype for the SIS-300 synchrotron of the FAIR facility at GSI. In order to minimize the losses produced by the fast ramp rate (1 T/s) at which the magnet is operated, we are developing with European industries, a Rutherford cable which incorporates several technologies to reduce the losses, and namely a NbTi filament diameter on the order of 2.5-3.5 μm, Cu 0.5 wt%Mn interfilamentary matrix and stainless steel core. In this paper we present the design principles and the first experimental results; we also analyze the impact of the CuMn paramagnetism on the field distortion at the different operating magnetic fields. [ABSTRACT FROM AUTHOR]

The upgrade of JT-60U to JT-60 Super Advanced (JT-60SA), a fully superconducting tokamak, will be performed in the framework of the Broader Approach (BA) agreement between Europe (EU) and Japan. In particular, the Toroidal Field (TF) system, which includes 18 coils, is foreseen to be procured by France, Italy and Germany. This work covers activities from design and manufacturing to shipping to Japan. The present paper is mainly devoted to the analyses that lead to the conductor design and to the technical specifications of the joints for the JT-60SA TF coils. The conductor geometry is described, which is derived from Cable-In-Conduit concept and adapted to the actual JT-60SA tokamak operating conditions, principally the ITER-like scenario. The reported simulations and calculations are particularly dealing with the stability analysis and the power deposition during normal and off-normal conditions (AC losses, nuclear heating). The final conductor solution was selected through a trade-off between scientific approach and industrial technical orientation. Besides, the TF system connections layout is shown, derived from the industrially assessed twin-box concept, together with the associated thermo-hydraulic calculations ensuring a proper temperature margin. [ABSTRACT FROM AUTHOR]

The adoption of High Temperature Superconductors (HTS) tapes is becoming a suitable and interesting alternative to copper for windings in transformers, thanks to the improvement in performance and the lowering of costs. Of course, optimized designs, different with respect to usual layouts, must be considered, due to the additional requirements of HTS tapes, such as minimization of orthogonal magnetic fields and consideration of additional losses in the HTS. In the framework of a scientific cooperation among some Italian Universities and private companies, a test model for a 10 KVA transformer with HTS secondary windings has been developed, and validated against a demonstrative prototype, manufactured during the project. In the paper, the device model performance is assessed, with particular care to the HTS losses modeling, and some comparisons to the experimental results are presented. [ABSTRACT FROM AUTHOR]