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The Super-FRS (Super FRagment Separator) is a part of FAIR (Facility for Antiproton and Ion Research), which will be constructed at GSI, Germany by 17 countries. The Super-FRS comprises 24 superferric dipole magnets. The 2D and 3D magnetic field simulations of the prototype magnet are described in this paper. A passive trim slot and four chamfered removable poles are used to satisfy the required field homogeneity which is better than ±3 x 10-4 at 1.6 T, 0.8 T and 0.16 T in a wide elliptical useable aperture of 380 mm 140 mm. Measurement results at various field levels are shown in this paper as well. It can be seen from the comparison of calculation and measurement results that the magnetic designs of the magnet fulfils the requirements. [ABSTRACT FROM AUTHOR]

Wendelstein 7-X (W7-X) is a superconducting stellarator under construction at the Max-Planck-Institute for Plasma Physics in Greifswald, Germany. The magnet system consists of 70 superconducting coils providing magnetic confinement-fields. Before assembly every coil had to pass an acceptance test at the French partner-institute CEA, Saclay, to examine its performance on leak tightness, high voltage strength, ampacity, and hydraulic flow at cryogenic conditions. The testing procedure was mandatory, as access for maintenance or repair after installation will not be viable. Testing followed a well specified routine including tests in warm conditions, during cool down, in cold conditions, during warm up and at last in warm conditions. Measurement was obtained firstly by the facility's instrumentation and secondly by the coil-casing's instrumentation. The received data was transmitted to different ASCII-files for each gauge. To record testing in detail, a meta-document was edited, which follows in its structure the routine mentioned above. Accordingly, the main distinctive functions of the coil during testing are recorded in so called test reports, while deviations from given thresholds and parameters are described in non conformity reports. During testing, organizational and technical challenges had to be mastered and the test program was regularly updated to meet technical improvements, manufacturing requirements and revised assembly schedules. This paper will present the acceptance test program, its development and the gained experiences. [ABSTRACT FROM AUTHOR]

Two Series-Connected Hybrid (SCH) magnets are under development at the National High Magnetic Field Laboratory. The first SCH is for the Helmholtz Centre Berlin (HZB) in Germany. The HZB SCH will be a horizontal bore, 30 T magnet and will be used for neutron scattering experiments. The second SCH is for the National High Magnetic Field Laboratory (NHMFL) in Tallahassee, FL. The NHMFL SCH will be a vertical bore, 36 T magnet. Both SCH Magnets combine a set of resistive Florida-Bitter coils with a superconducting outsert coil constructed of cable-in-conduit conductor (CICC). The two SCH magnets are designed for various operating scenarios including those with multiple ramp cycles at various rates. Both of the superconducting magnets are forced flow cooled with supercritical helium at 4.5 K. A standard refrigerator with a capacity of about 150-200 W at 4.5 K will be used to supply the cooling power and the forced mass flow rate. The cryogenic system of the SCH magnet consists of a helium refrigerator, a valve box with subcooler, a magnet cryostat and cryolines. In this paper, the design of the cryogenic system is described. [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 Forschungszentrum Juelich (FZJ) has taken the leadership of a consortium to design and construct the HESR as part of the Facility for Antiproton an Ion Research (FAIR) project at the Gesellschaft fuer Schwerionenforschung (GSI) in Germany. The HESR is a 50 Tm synchrotron/storage ring for antiprotons using superconducting magnet technology, where the development of a bent dipole magnet (cosine theta) with a radius of curvature of 13.9 m and a length of 3.3 m is the major task. On basis of the HERA cooling system the cryogenic design for the HESR has started. One key issue will be the design of several cold-warm, transitions e.g. at PANDA, the E-Cooler and in the region of the stochastic beam cooling system. Another important development is the cryostat layout housing the superconducting curved magnets and in particular the alignment system and measurement equipment for the bent magnets. This paper will present an overview both of the cryogenic layout and the cryostat design. It will give a status report on the achievements so far and discuss the future plans. [ABSTRACT FROM AUTHOR]

The Wendelstein 7-X (W7-X) stellarator fusion experiment is presently under construction at the Max-Planck-Institut für Plasmaphysik in Greifswald Germany. The W7-X machine has a superconducting magnet system with 50 non-planar and 20 planar coils grouped in five equal modules. The operation of the W7-X machine requires a reliable insulation system of the superconducting magnets. Starting in the design phase the components have to consider the insulation system, weak points of the insulation must be identified and countermeasures must be taken, e.g. for the crossings of conductors inside the windings, the shape of handmade insulated areas and the quench detection cable design. The manufacturing has to be based on qualified procedures and materials, e.g. the vacuum pressure impregnation of the glass epoxy insulation as well as the hand-made glass epoxy wrappings must be thoroughly qualified and tested during the whole manufacturing process. A set of accompanying tests, especially high voltage tests, during the manufacturing and assembly process helps to assure the quality of the insulation. [ABSTRACT FROM AUTHOR]

The Forschungszentrum Jülich is responsible for the complete design and the construction of the High-Energy Storage Ring HESR, at the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany. This includes the layout and provision of all magnets where the dipole, quadrupole and sextupole magnets are the most important. All magnets will be iron-dominated and normally conductive. The distance between the magnets is small due to the restricted space in the tunnel. In contrast to isolated magnets, differences are expected for the effective magnetic length as well as the integrated higher-order multipole contributions. In this publication, the results of magnetic-field calculations are presented that assess the magnetic interaction of neighboring magnets. [ABSTRACT FROM AUTHOR]

The international FAIR project planned next to G.S.I. (Germany) will lead to the construction of two superconducting synchrotrons (SIS100 and SIS300). This article reports on the quench calculations and measurements performed on one short SIS100 dipole model (1.4 m), the first to be tested at the FAIR prototype test facility. Quench propagation velocities and time to reach the 0.2 V quench threshold were measured in the bus bars and compared to computed values. The hotspot temperature was measured for different Miits (integral of I2.dt) values at 6 and 8 kA and compared to temperatures computed with the Miits equation. This article also reports the use of one inductive spot heater. [ABSTRACT FROM AUTHOR]

Fault current limiters (FCL) have been developed using high temperature superconductors. Possible applications of FCL are medium and high voltage energy supply systems. In this field conventional protection against high currents often cause high expenses. Using a superconducting FCL gives an economic advantage, if technical problems can be solved at lower costs or if the usage of a FCL makes savings in other equipment possible. This work deals with possible applications of a superconducting fault current limiter in a medium voltage auxiliary power network of a typical small cogeneration power plant. For possible installation locations in the existing energy supply system of Braunschweig, Germany, calculations of short circuit currents were made. It is investigated, whether the power plant can be expanded while staying or becoming short-circuit-proof. One result of the work is that the auxiliary power system of the power plant is an especially interesting installation location for a FCL. Advantages of a FCL compared to conventional strengthening of the installations are discussed. [ABSTRACT FROM AUTHOR]

The National High Magnetic Field Laboratory (NHMFL) has been funded to design and construct two series-connected hybrids (SCH), one each for the NHMFL in Tallahassee, FL and the Helmholtz Centre Berlin for Materials and Energy (HZB), Germany. The original designs for both hybrids contained three concentric coils comprising a Nb3 Sn superconducting cable-in-conduit (CIC) main-field outsert coil, a resistive main-field insert coil and a NbTi superconducting CIC shield coil. The fringe field requirements for both facilities were met by designing the NbT1 shield coil to match the 9.6 x 106 A-m2 dipole moment of the main field coils at an average radius of 1.16 m. Subsequent, alternate magnetic shielding concepts for both hybrids have been investigated with the objective of reducing the anticipated $700 k NbTi shield coil cost. The HZB fringe field requirements were targeted to a local area of concern at the adjacent Spin Echo facility, centered 15.65 m from the hybrid magnet center. An alternate, lower-cost shield concept comprised a set of four smaller shield coils positioned orthogonally around the HZB spin echo facility with a resultant total 85% to 90% reduction in required dipole moment compared to the original NbTi shield coil. The fringe field requirements at the NHMFL were not changed, but a lower-cost iron shielding option (not described here) located around the NHMFL hybrid was found to be a viable alternative. As a result, the NbTi CIC coil can be eliminated from the common superconducting magnet design for both the HZB and the NHMFL SCH's in favor of viable lower cost shielding options. [ABSTRACT FROM AUTHOR]

Fermilab is building a cryomodule containing four 3.9 GHz superconducting radio frequency (SRF) cavities for the Free electron LASer in Hamburg (FLASH) facility at the Deutsches Elektronen-SYnchrotron (DESY) laboratory. Before assembling the cavities into the cryomodule, each individual cavity is tested at Fermilab's Horizontal Test Stand (HTS). The HTS provides the capability to test fully-dressed SRF cavities at 1.8 K with high-power pulsed RF in order to verify that the cavities achieve performance requirements under these conditions. The performance at the HTS of the 3.9 GHz cavities built for FLASH is presented here. [ABSTRACT FROM AUTHOR]

Two world-first High-Tc Superconducting (HTS) beamline magnets have been designed, manufactured and commissioned for synchrotron and neutron research facilities. One, for the Hahn-Meitner Institut, is for use with their high-resolution diffraction and resonant magnetic scattering instrument MAGS at the Berlin electron synchrotron facility BESSY. The key features of this 5 tesla split-pair magnet include field performance within a given confined geometry, and low weight. Mounting in a 6-circle goniometer and employing conduction-cooled HTS coils, it operates through 90 degrees of rotation with respect to the beamline axis and scattering plane. The neutron beamline magnet is also a 5 tesla split pair, designed for both neutron reflectometry and small-angle neutron scattering research at the new OPAL neutron facility of the Australian Nuclear Science and Technology Organisation. This much larger magnet offers wideneutron beam accessibility angles in both axial and transverse directions, large (50 mm) sample capability, and mounts on tilt stages operating in two axes. Both magnets use pulse-tube refrigeration for the HTS coils, which have been constructed from high performance BSCCO wire, and both are compatible with separate commercial cryofurnaces providing sample temperatures from 1.5 K (MAGS) or 4 K (OPAL) to over 600 K. [ABSTRACT FROM AUTHOR]

The dipole magnets for the new heavy-ion synchrotron SIS-100, planned within the Facility for Anti-Proton and Ion Research (FAIR) at GSI, Darmstadt, Germany, have to be optimized under certain design requirements. At the intended high beam intensities, the field quality in the aperture is crucial. The geometry of the window-frame magnet featuring superconductive coils was already optimized with respect to the field quality in terms of higher-order multipoles using static 2D and 3D Finite Element (FE) simulations. During fast ramping up to 2 T, however, additional perturbations arise due to local saturation and due to eddy currents in both the yoke and the metallic beam pipe. These have already been investigated using transient 2D FE simulations. In order to further refine these results, a transient nonlinear 3D FE model, capturing the eddy-current effects at the end plates is used. The results are compared to those obtained by static simulations. [ABSTRACT FROM AUTHOR]

A new plasma fusion experiment, Wendelstein 7-X (W7-X), is built in the Max-Planck Institute for Plasma Physics in Greifswald (IPP), Germany. This experiment employs superconducting coils, allowing for plasma discharges up to 30 minutes duration. W7-X will be an "optimized" stellarator with respect to plasma transport and stability. The W7-X magnet consists of 70 individual coils in a toroidal arrangement. Each coil of W7-X is thoroughly tested before installation in a cryogenic test facility at the Commissariat a l'Energie Atomique (CEA) in Saclay, France. The tests are essential, because no access is foreseen to the magnetic system during the entire operation period of W7-X. The test procedure will be described briefly, and some test results will be presented. [ABSTRACT FROM AUTHOR]

The Max-Planck-Institut für Plasmaphysik is building the stenarator fusion experiment WENDELSTEIN 7-X (W7-X) at the branch institute in Greifswald, Germany. The 50 non-planar superconducting coils are currently manufactured by industry and use a specially developed NbTi cable-in-conduit conductor. The manufacture of the coils includes the conductor, winding of the conductor, vacuum pressure impregnation as well the embedding of the winding pack into a cast steel casing, the final machining and the installation of the helium cooling system on the casing. Design changes became necessary during production in the connection areas of the casings due to more detailed design and structural analysis. In addition, the insulation and the welds in the termination area need to be improved. New quench detection cables were qualified. LINAC inspections allowed to check the presence of casting defects in the thick casings. Additionally high voltage tests in vacuum under Paschen-minimum conditions turned out to be a very sensitive inspection method to check the integrity of the electrical insulation. [ABSTRACT FROM AUTHOR]

Two superconducting synchrotrons, SIS100 and SIS300, are planned for the new International Accelerator Facility of Antiprotons and Heavy Ions (FAIR) at GSI, Darmstadt. These accelerator rings, operating at liquid helium temperatures, are placed in one tunnel of 1100 m length. The SIS100 structural superferric dipoles and quadrupoles are based on the Nuclotron-type hollow NbTi composite multi wire cable and cooled in parallel with two-phase helium flows. The peak operating mode for the SIS100 dipoles corresponds to Bmax = 2 T, dB/dt = 4 T/s, f = 1 Hz. Fast-ramped dipoles (dB/dt ≈ 1 T/s, f ≈ 0.05 Hz) with a field strength of 4 T and above are required for the SIS300 ring. A 4.5 T, cos θ-style, curved magnet with a coil made of a high current hollow cable cooled with two-phase helium flow is proposed for SIS300. The necessary modifications of the magnet cooling scheme are presented and discussed. General optimization of the SIS100/300 cryogenic system namely cooling with three refrigerators, the number of parallel channels, the length of helium transfer lines, and a closed nitrogen loop for the heat shield cooling is considered. The new design will make it possible to reduce the FAIR project cost. [ABSTRACT FROM AUTHOR]

New results from the investigation of 2 T superferric model dipoles operating at 4 T/s, 1 Hz are presented. The works are performed within the R&D program on the design of the SIS100 synchrotron at GSI in Darmstadt. One of the main research goals is minimization of overall AC power losses in the magnet at 4 K level. Different modifications of the dipole were proposed and tested experimentally. By the present time, the losses are reduced to about 17 W/m of the magnet length, while the reference Nuclotron dipole produces about 38 W/m in the same operating mode. Essential design details of the model magnets are described and further R&D steps are outlined. [ABSTRACT FROM AUTHOR]

By the end of 1998, Babcock Noell Nuclear (BNN) as part of the Consortium Wendelstein was awarded with the fabrication of the nonplanar module field coils for the Wendelstein 7-X experiment to be built at Greifswald. In 1999 and 2002, BNN received orders for the production of LHC dipoles to be installed at CERN. Both projects are performed in parallel; therefore challenging tasks had to be solved not only from a technical but also from an industrial point of view. We present the solutions we found for the set-up of the production facilities, which include the development of tools suitable for series production and the recruitment of capable staff. An overview of the different production steps for both magnet types will be given as well as an outline about the quality measures that has been established. As in total 416 dipoles and 50 nonplanar coils consisting of a lot of high-quality components are fabricated, logistics within the company and the consortial partners as well as to subsuppliers is an issue, too. Both types of magnets are on the forefront of what is technically feasible. Therefore feedback from test results and possible improvements of the fabrication processes are always an issue. Besides that, technical changes introduced for knowledge gained only at a later stage of the project had to be introduced in the fabrication process. [ABSTRACT FROM AUTHOR]

A full scale three-phase resistive high-Tc superconducting fault current limiter (SCFCL) designed for 10 kY, 10 MVA, has been developed, manufactured, and tested within a publicly funded German project called CURL 10. The device is based on 90 bifilar coils of MCP BSCCO-2212 bulk material. The operating temperature of 66 K is achieved by cooling of liquid nitrogen using two Stirling cryocoolers. Until today, this is the largest HTS fault current limiter world wide. We report on the design features, the composition, and the operation parameters of the SCFCL system. From April 2004 on CURL 10 is installed and tested within the net- work of the utility RWE at Netphen near the city of Siegen, Germany. The results of the laboratory test and the field test of CURL 10 are given. [ABSTRACT FROM AUTHOR]