Numerous industrial applications such as aluminum smelters, electrolysis plants and large data centers, require DC feeding currents of several hundred kA. Within the project DEMO200, a demonstrator for a superconducting single-pole 200 kA DC busbar was developed, including suitable current leads. The demonstrator consists of ten identical modules, each with a current capacity of 20 kA. The ten modules are electrically connected in series since a 200 kA DC source was unavailable for testing purposes. Thus, the magnetic self-field effects and Lorentz forces are the same as in the parallel target configuration, but a 20 kA source is sufficient. The demonstrator has a length of 2 m and its ten modules are each based on sixty 12 mm wide REBCO superconducting tapes. The modules are joined in a compact structure with a diameter of 300 mm which withstands thermal contraction and the large Lorentz forces. The demonstrator's design operation temperature was 70 K, but finally the tests were conducted at 77 K. Despite this shortcoming, DEMO200 carried a current of 10 x 18.9 kADC. The current leads and low ohmic connectors complied with the requirements. As a result, SuprAl, a 600 m long busbar, is now being built for TRIMET in Hamburg and is also presented.

In this paper, the dynamic response characteristics of the suspension vehicle system caused by the quenching of superconducting magnets are investigated. Based on the established full-coupled magnetic/rail calculation model of the electric suspension system in the closed-loop operation mode of superconducting magnets, the superconducting magnet quenching at different positions is numerically simulated and analyzed, considering the superposition effect of dynamic electromagnetic force fluctuations and track irregularities. In addition, the moving interval algorithm is adopted to solve the long track line in the dynamic model, which significantly improves the computational efficiency of the model. The results show that the quenching of non-articulated frame magnets has a greater impact on the safety of the suspension vehicle than that of articulated frame magnets. The quenching of the middle magnets has a greater impact on the lateral and vertical dynamic response changes of the suspension vehicle system. The position of the quenched magnet has a significant impact on the safety and dynamic response characteristics of the suspension vehicle.

A stepped-groove twisted stacked-tape cable (TSTC) is investigated to evaluate its current-carrying performance under bending-related mechanical conditions, with a conventional VIPER conductor used for comparison. Mechanical simulations are performed to obtain the axial strain distribution of individual tapes, and the resulting strain-induced critical current degradation is incorporated into the electromagnetic model through a force-electromagnetic coupling approach. The coupled analysis shows that, although bending reduces the critical current in both designs, the stepped-groove TSTC maintains a more uniform current density distribution and a higher critical current than the VIPER configuration. These results demonstrate the advantage of the stepped-groove design in mitigating bending-induced performance degradation.

The properties of superconducting joints for REBa<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>Cu<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub>O<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">_y</i> (REBCO, RE = rare earth) superconducting tapes fabricated using a slurry process were investigated. Microstructural observation revealed that a joining layer fabricated using a slurry was well-connected to the REBCO layer of the joined tape. The resistance and critical current of closed-loop samples containing slurry-processed superconducting joint were evaluated using current decay measurements. The joint resistance was found to be lower than 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−12</sup> and 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−11</sup> Ω at 4 and 77 K, respectively, in the self-field. It is inferred that a persistent current can flow through a slurry-processed superconducting joint. Conversely, in-field critical current was low and exhibited hysteresis due to weak links in the joining layer.

Pulsed Laser Deposition (PLD) offers a powerful route for the fabrication of high-quality YBCO films with exceptional crystallographic alignment. In this study, the influence of film thickness on the corresponding electrical properties was investigated, with a particular emphasis on their correlation with microstructural features. Transport measurements indicate that the critical current density (Jc) shows a progressive decline as the film thickness increases, a phenomenon that can be directly related to the microstructural characteristics observed. These findings provide valuable insight into the inherent challenges associated with growing thick films and may guide future strategies for optimizing their properties in high-field applications. Furthermore, understanding these mechanisms is crucial for advancing the design and performance of high-temperature superconducting magnets and other electronic devices that require thick, high-performance films.

Superconducting powertrain is critical for next-generation electric aircraft, allowing for lossless power transmission and significantly increasing efficiency, performance, and range. A superconducting fault current limiter (SFCL) is a device on the DC side that uses superconducting materials to control excessive current during faults, thereby protecting the powertrain and enhancing system stability. Among several superconducting fault current limiters (SFCLs), resistive SFCLs (R-SFCLs) have benefits such as compactness, lightweight, high reliability, and a fail-safe nature. When subjected to alternating magnetic fields or currents, superconducting materials exhibit hysteresis, eddy currents, and flux flow effects, which lead to energy dissipation and reduced efficiency. This also applies to R-SFCLs operating under normal conditions in the superconducting state, where AC losses occur and require appropriate thermal management to mitigate heat generation and prevent unexpected quenching. DC current ripple and its harmonic contents in an R-SFCL cause additional losses, increasing joule heating and potentially driving the superconductor out of its superconducting state, reducing its efficiency and fault-limiting capability. This research was conducted from two perspectives: theoretical calculations and experiments. The objective is to study the losses in the R-SFCL within the superconducting system, including ripple and harmonic effects, and to determine the design parameters of the R-SFCL cooling system to minimise thermal impacts.

Over the past few years, interest in a Muon Collider as a potential post-LHC machine has grown significantly. By colliding muons, it is possible to achieve both precision and high energy, overcoming the limitations of synchrotron radiation in conventional lepton colliders. However, the very short muon lifetime at rest requires high beam intensity and fast acceleration rates limiting the collider ring dimensions. These limitations lead to several challenges in the design of superconducting magnets, which must generate high magnetic fields in large apertures to provide shielding from the radiation due to muon decay. This work explores the design of combined function magnets, which are essential to address the neutrino flux issue in straight sections by bending the particles during focusing/defocusing stages. The superconducting material selected for these magnets is REBCO, a High Temperature Superconductor (HTS), with operating temperatures ranging from 4.5 K to 20 K. Various configurations of combined function magnets are studied and simulated using a Python code interfaced with the Finite Element Method (FEM) software ANSYS, employing the sector coil approximation. The goal is to identify feasible designs that can accommodate substantial internal shielding while continuing to provide the high fields and gradients demanded by the lattice optics. To validate the manufacturability of such concepts, a preliminary winding test has been performed using Nb<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$_{3}$</tex-math></inline-formula>Sn in a Canted-Cosine-Theta (CCT) geometry. While REBCO represents the most promising HTS conductor for future high-field applications, Nb<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$_{3}$</tex-math></inline-formula>Sn remains one of the most mature options for large accelerator magnets, providing a valuable feasibility benchmark.

During the Long Shutdown 3 of the LHC, scheduled to start in 2026, the interaction regions will be upgraded to increase the integrated luminosity by about one order of magnitude. Among the components to be replaced are the MBRD (Main Bending Recombination Dipole, also known as D2), which are double-aperture magnets providing aligned magnetic fields to steer the two beams into the ATLAS and CMS experiments and subsequently recombine them onto their nominal trajectories. To meet the demanding requirements of the High-Luminosity LHC, a new magnet design was developed by INFN-Genova, featuring a larger aperture, a higher operating field, and innovative solutions to mitigate the strong electromagnetic cross-talk between the apertures while ensuring mechanical integrity against the large repulsive Lorentz forces. The development program included the construction of a 1.6-m model, a full-length prototype, and six series magnets, of which four will be installed in the LHC and two kept as spares. Series production is ongoing at ASG Superconductors, and the first magnet has been successfully cold-tested at CERN. This contribution reports on the main challenges faced during series production and discusses the first test results.

RE-Ba-Cu-O (REBCO) bulk high temperature superconducting undulators have been experimentally demonstrated to generate undulator fields exceeding 2 T at a 10 mm period, outperforming alternative undulator technologies for short-period applications. This study aims to further enhance undulator performance by reducing the period length through optimization of staggered-array, half-moon-shaped REBCO bulks. We propose a novel dual-lunate-ring-based REBCO undulator geometry that enables control of magnetization currents within individual lunate rings. The coexistence of magnetization currents on both the upper and lower sides of the undulator axis contributes to a significant enhancement of the on-axis magnetic field. To evaluate the performance of this design, the undulator period and gap were fixed at 7 mm and 3.3 mm, respectively, while the dimensions of the bulk rings were optimized numerically using the H-formulation. When the background solenoidal field changes from 10T to zero (ΔBs = 10 T), the undulator is expected to achieve a field strength B0 of 1.65T with a 7 mm period, corresponding to a deflection parameter of K = 1.1.

The magnetic field is an outstanding experimental tool for physics. To go beyond the conventional commercially available superconducting (SC) magnets, very large infrastructures such as the ones gathered within the European Magnetic Field Laboratory (EMFL) are necessary. The SuperEMFL project is a design study aiming at providing the European high field user community with much higher superconducting fields. This is meant to be achieved by combining high temperature superconductor (HTS) insert magnets, an emerging technology that can work in fields above 25T, with low temperature superconductor (LTS) outsert magnets, a technology limited to fields below 25 T. The project has two design magnetic field targets, 32+T and 40+T. The first design target proposed to combined a single stack of HTS pancakes in combination with a 19 T / 150 mm LTS magnet; the second either a similar arrangement at the sake of a narrower central space or a design with two nested HTS coils combined with a 15 T/ 250 mm LTS magnet. The particular choice of the project is to use no insulation but a metallic tape co-wound with the bare HTS tape. This so-called Metal as Insulation (MI) technology enables a self-protection feature of the HTS coil by allowing the electrical bypass of defects as well as better mechanical performances in a very compact winding. The use of HTS inserts introduces a change of paradigm by providing an unprecedented combination of high magnetic field and long measurement times whilst saving vast amounts of energy in operation.