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Applied Superconductivity, IEEE Transactions on

Issue 1 • Date March 2002

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Displaying Results 1 - 25 of 403
  • 17th International Conference on Magnet Technology

    Publication Year: 2002 , Page(s): 1 - 16
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    Freely Available from IEEE
  • Eddy currents and their effects on the mechanical structures of the Dynamic Ergodic Divertor of the TEXTOR 94 tokamak

    Publication Year: 2002 , Page(s): 1463 - 1466
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    The Dynamic Ergodic Divertor (DED) of the TEXTOR 94 tokamak will work at the regimes of DC current and AC current at frequencies up to 10 kHz. In order to design the mechanical structures supporting the DED coils and the graphite protective tiles it is necessary to take into account the induced eddy currents, especially at high frequencies. The temperature rise and mechanical forces in the structures should be within acceptable limits. The screening effect of the DED coils in the plasma region should be minimized. The modeling of the DED electromagnetic field is discussed. The problem is solved numerically with the ANSYS code. For comparison, some simplified technique is employed. Two approaches are used for the different types of structures: thin shell approach and infinitely thin skin-layer approach. The eddy currents and energy losses in the structures have been defined. The 2-D and 3-D nonstationary thermal problems have been solved and the temperature rise in the structures has been calculated for the steady state regimes. The evaluation of the static and cyclic strength of the structures has been made. Based on parametric studies, the parameters of the coil and tile supporting structures have been optimized. View full abstract»

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  • An evaluation of mechanical properties of YBaCuO and (Sm,Gd)BaCuO bulk superconductors using Vickers hardness test at cryogenic temperatures

    Publication Year: 2002 , Page(s): 1755 - 1758
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (410 KB) |  | HTML iconHTML  

    Vickers hardness properties of bulk superconductors have been investigated to estimate the mechanical properties of bulk materials. However, the test at cryogenic temperatures had not been conducted at all. Then we conducted Vickers hardness test on (001) plane of YBaCuO and (Sm,Gd)BaCuO bulk superconductors from 40 to 293 K. The hardness of YBaCuO and (Sm,Gd)BaCuO increased with decreasing temperature up to 19 000 MPa and 10 000 MPa, respectively. Furthermore, the cracks caused by the indentation were observed with SEM, and the fracture toughness KIC at cryogenic temperatures was calculated. The KIC of YBaCuO and (Sm,Gd)BaCuO decreased with decreasing temperature to 0.6 MPa√m and 0.8 MPa√m, respectively. View full abstract»

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  • Testing of a cryocooler-cooled HTS magnet with silver-sheathed Bi2223 tapes for silicon single-crystal growth applications

    Publication Year: 2002 , Page(s): 984 - 987
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (323 KB) |  | HTML iconHTML  

    A project to develop a high-temperature superconducting split magnet for 8 inch silicon single-crystal growth applications began in October 1997. This split coil system is composed of 2 coils, each consisting of 18 pancakes. Each coil has an outer diameter of 1.2 m and a thickness of 0.1 m. Moreover, we developed a highly efficient GM-type cryocooler to cool a HTS coil to below 20 K. This paper presents the test results for a full-scale magnet. Each coil was cooled by the GM-cryocooler with a 3.3 kW compressor. The cool-down of the coil was completed within 480 hours with temperature difference among pancakes maintained at less than 18 K. In April 2001 this split coil was successfully energized up to rated current of 210 A at 20 K without a quench. The stored energy of this split coil reached 1.1 MJ at 216 A, 20 K, and the fastest charging time in our experiments was 1 minute. View full abstract»

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  • Electromagnetic loads on the KSTAR magnet system

    Publication Year: 2002 , Page(s): 534 - 537
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (199 KB) |  | HTML iconHTML  

    Several types of Lorenz forces and Joule heating generated in the magnet system of the Korea Superconducting Tokamak Advanced Research (KSTAR) device have been studied numerically and analytically. We have examined 225 plasma equilibrium states to calculate the maximum magnetic forces and to determine which equilibrium state(s) generate such forces. The obtained results are used as input for structural analysis. A precompression should be applied to the eight-segmented central solenoid (CS) coil assembly to prevent free motion of each coil due to attractive and repulsive forces during operation. We have also evaluated the maximum values of the vertical and lateral forces for each of the CS coils and poloidal field coils and also for the entire CS coil stack. The in-plane force due to toroidal field (TF) coil charging and the out-of-plane force due to interaction of the TF coil current with the poloidal field have been computed. The Joule heating on the TF structure due to plasma disruption has also been calculated. View full abstract»

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  • Measurements of interstrand thermal and electrical conductance in multistrand superconducting cables

    Publication Year: 2002 , Page(s): 1052 - 1055
    Cited by:  Papers (4)
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    A new apparatus has been developed to investigate interstrand contact properties of multistrand superconducting cables. The apparatus can measure interstrand electrical and thermal conductance simultaneously. Two NbTi samples were measured and influences of surface coating, contact force and pressing history on contact properties were investigated. These measurements provide essential data for theoretical analyses of stability of multistrand superconducting cable against local disturbances. View full abstract»

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  • The dipole magnet design for the ALICE DiMuon arm spectrometer

    Publication Year: 2002 , Page(s): 399 - 402
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (233 KB) |  | HTML iconHTML  

    An essential part of the DiMuon Arm Spectrometer of the ALICE experiment is a conventional Dipole Magnet (DM) of about 890 tons, which provides the bending power to measure the momenta of muons. The JINR engineering design of the DM, technical characteristics and description of the proposed manufacturing procedure are presented. The proposed coil fabrication technique is based on winding of flat pancakes, which are subsequently bent on cylindrical mandrels. The pancakes are then stacked and cured with prepreg insulation. The method is demonstrated on hand of the prototype II, which consists of a pancake made with full-size aluminum conductor. Some details of electromagnetic and mechanical calculations are described. The results of measuring of mechanical and electrical characteristics of materials related to the coil composite structure are discussed. View full abstract»

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  • Resistances of electrical joints in the TF model coil of ITER: comparisons of first test results with samples results

    Publication Year: 2002 , Page(s): 543 - 547
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (250 KB) |  | HTML iconHTML  

    The test of the Toroidal Field (TF) Model Coil of the International Thermonuclear Experimental Reactor (ITER) has been the opportunity to measure the DC resistances of all the joints of a real coil and to compare them to values previously measured on prototype full-size joint samples. This paper describes and discusses the different methods used for measuring all the joint resistances, and gives the results of joint resistance measurements (1-2 nΩ range) as function of the coil current up to the maximum value of 80 kA. Comparisons with resistances measured on prototype joints in relevant field/current conditions are presented and discussed. View full abstract»

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  • 3-D optimal shape design of ferromagnetic pole in MRI magnet of open permanent-magnet type

    Publication Year: 2002 , Page(s): 1467 - 1470
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (241 KB) |  | HTML iconHTML  

    This paper presents 3-D optimal shape design method of ferromagnetic pole pieces for magnetic resonance imaging (MRI) devices of open permanent magnet type. The design method is based on a continuum sensitivity analysis in conjunction with the boundary integral equation method (BIEM). The magnetic poles of an open magnet assembly are designed by the proposed method and the conventional shimming method. Magnetic field strength, ppm order homogeneity and working space volume are compared between the proposed method and conventional one. View full abstract»

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  • Design and test of the titanium alloy tie rods for the CMS coil suspension system

    Publication Year: 2002 , Page(s): 403 - 406
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (298 KB) |  | HTML iconHTML  

    The Compact Muon Solenoid (CMS) is one of the general-purpose detectors to be provided for the LHC project at CERN. The design field of the CMS superconducting magnet is 4 T, the magnetic length is 12.5 m and the free bore is 6 m. Thirty titanium alloy tie rods are used to support the 225 tonne weight of the cold mass inside its vacuum vessel and react against the forces generated by potential magnetic misalignment. This paper describes the suspension system and its mechanical analysis in different loading cases corresponding to operating conditions of the magnet. Two grades of titanium alloy are foreseen (Ti 6 Al 4 V ELI and Ti 5 Al 2.5 Sn ELI). Based on mechanical tests at room temperature and at 4.2 K, the safety criteria are analyzed for both materials. Before final installation, all tie rods will be tested at 110% of the maximum load with one end at room temperature and the other one at cryogenic temperature. The test system and the test results of the prototype tie rods are also presented. View full abstract»

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  • Method for determination of the conductor current sharing temperature using traveling heat slug in the ITER TFMC

    Publication Year: 2002 , Page(s): 1533 - 1536
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (238 KB) |  | HTML iconHTML  

    During the TFMC (Toroidal Field Model Coil) quench experiment, a part of the pipe supplying helium to the TFMC is heated in order to reach, by forced circulation, the current sharing temperature of the conductor at peak field. During this experiment, the TFMC conductor is supplied with a current of 80 kA and the maximum magnetic field on the tested pancake is around 7.2 T. The aim of this paper is to determine the values of the experimental conditions needed to quench the TFMC conductor before the joint. View full abstract»

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  • Shape design sensitivity for force density distribution of magnetic systems

    Publication Year: 2002 , Page(s): 1471 - 1474
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    This paper presents a design method for handling magnetic force density distributions in 2-D linear magnetic systems. In order to control not the global force but the distribution of local force density, the discrete sensitivity analysis is combined with the magnetic charge method. For calculation of the magnetic force density, we use the magnetic charge method that is valid from the viewpoint of mechanical deformation. The design sensitivity is obtained through the direct differentiation of the finite element system matrices. Two models of a levitated rod and a cantilever electromagnet are designed to produce the desired force density distribution. Their results show the validity of the proposed method. View full abstract»

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  • A new support structure for high field magnets

    Publication Year: 2002 , Page(s): 47 - 50
    Cited by:  Papers (24)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (234 KB) |  | HTML iconHTML  

    Pre-stress of superconducting magnets can be applied directly through the magnet yoke structure. We have replaced the collar functionality in our 14 Tesla R&D Nb3Sn dipole magnets with an assembly procedure based on an aluminum shell and bladders. Bladders, placed between the coil pack and surrounding yoke inside the shell, are pressurized up to 10 ksi [70 MPa] to create an interference gap. Keys placed into the interference gap replace the bladder functionality. Following the assembly, the bladders are deflated and removed. Strain gauges mounted directly on the shell are used to monitor the stress of the entire magnet structure, thereby providing a high degree of pre-stress control without the need for high tolerances. During assembly, a force of 8.2 × 105 lbs/ft [12 MN/m] is generated by the bladders and the stress in the 1.57" [40 mm] aluminum shell reaches 20.3 ksi [140 MPa]. During cool-down the thermal expansion difference between shell and yoke generates an additional compressive force of 6.85 × 105 lbs/ft [10 MN/m], corresponding to a final stress in the shell of 39.2 ksi [270 MPa]. Pre-stress conditions are sufficient for 16 T before the coils separate at the bore. Bladders have now been used in the assembly and disassembly of two 14 T magnets. This paper describes the magnet structure, assembly procedure and test results. View full abstract»

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  • Construction and measurement of the pre-series twin aperture resistive quadrupole magnet for the LHC beam cleaning insertions

    Publication Year: 2002 , Page(s): 55 - 58
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (309 KB) |  | HTML iconHTML  

    CERN's Large Hadron Collider (LHC) requires 48 twin aperture resistive quadrupoles in the beam cleaning insertions. Canada is contributing these magnets to CERN in the framework of the TRIUMF-LHC collaboration contracts. A pre-series magnet was produced by Canadian industry and delivered in March 2001. This magnet incorporates important design changes that resulted from experience with a prototype magnet. The construction of this pre-series magnet and the measurements made at ALSTOM and at CERN are reported. A comparison is made between high precision pole distance measurements and the magnetic measurements performed with a rotating coil mole. Conclusions for series production and possibilities for multipole corrections are outlined. View full abstract»

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  • Protection of superconducting magnets

    Publication Year: 2002 , Page(s): 1390 - 1395
    Cited by:  Papers (6)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (235 KB) |  | HTML iconHTML  

    The protection of superconducting magnets can be narrowly considered as the problem of rapidly detecting an irreversible loss of superconductivity (quench) and converting the magnetic stored energy to thermal energy (dump) without permanent damage (protection). It can also be broadly considered as a method for avoiding all structural and electrical failure mechanisms through design, fabrication, and operation of a magnet. Energy dump and quench detection methods are reviewed. General magnet failure is surveyed historically. View full abstract»

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  • Design and fabrication of an HTS reciprocating magnetic separator

    Publication Year: 2002 , Page(s): 971 - 974
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (204 KB) |  | HTML iconHTML  

    The conceptual design and fabrication details of a conduction-cooled high temperature superconducting (HTS) reciprocating magnetic separator are reported. Reciprocating magnetic separators are used in the purification of kaolin clay. The HTS coil is 0.30 m in length and has a 0.25 m inner diameter. The central operating magnetic field is a nominal 3.0 T with a design operating current of 126 A. In terms of combined size and magnetic field strength, this is one of the largest HTS magnets ever fabricated, possessing a stored energy >0.1 MJ. The HTS magnet is conduction cooled via one single-stage G-M cryocooler with a nominal operating temperature of 30 K. The HTS conductor uses a stainless steel reinforced Bi-2223 material. Salient features and results of the electromagnetic, thermal, and quench protection analyses are discussed. View full abstract»

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  • Feasibility study of oxide superconducting transformers for Shinkansen rolling stock

    Publication Year: 2002 , Page(s): 828 - 832
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (274 KB) |  | HTML iconHTML  

    A feasibility study of an oxide superconducting transformer for Shinkansen rolling stock was made from the viewpoint of light weight. On the basis of the observed critical current and AC loss properties for the currently developed Bi2223 silver-sheathed superconducting wires, which both have large anisotropy, superconducting transformers cooled by subcooled liquid nitrogen with the same specifications as the conventional ones were designed. The total weight of the transformer system including a cryocooler was quantitatively evaluated. As compared with the weight of conventional ones, the optimum winding configuration and 1-turn voltage were searched for. As a result, the following suggestion was obtained. For the sake of light weight, the transformer should be core type with closely wound cylindrical windings so as to reduce the perpendicular magnetic field to the wide surface of superconducting thin wires and the AC loss in a superconducting wire needs to be much reduced as compared with the currently developed one. Finally, according to the obtained optimum parameters, the conceptual design of a single-phase 4 MVA-25 kV superconducting transformer for Shinkansen rolling stock was performed whereby the drastic reduction of weight was shown. View full abstract»

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  • Effect of γ-irradiation on silver-sheathed Bi1.6Pb0.4Ba2Ca2Cu3O10 tapes

    Publication Year: 2002 , Page(s): 1121 - 1123
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (188 KB) |  | HTML iconHTML  

    Specimens with nominal composition Bi1.6Pb0.4Ba2Ca2Cu3O10 were prepared using the powder-in tube technique. The effect of γ-irradiation at room temperature on the superconducting properties have been investigated using x-ray diffraction, resistivity measurements and I-V characteristics. The intensities of the main diffraction peaks decrease by about 25%, however, the peak positions do not change with γ-irradiation up to a dose of 400 MR. The normal state resistance R(T) increases gradually up to a dose of 100 MR, whereas at higher doses, the effect of irradiation becomes rather negligible. The transition temperature Tc decrease slightly and the transition temperature width ΔT broadens at doses below 100 MR with almost no change at higher doses up to 400 MR. At relatively low magnetic fields and low γ doses, the critical current densities Jc(B) increase with γ-irradiation, while the effect of γ-irradiation at relatively high magnetic fields is hardly observable. These results are discussed and explained in terms of the effect of γ-rays on the weak links grain boundaries and Josephson junctions between the grains. View full abstract»

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  • A device for measuring high current at cryogenic temperatures

    Publication Year: 2002 , Page(s): 1264 - 1268
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (276 KB) |  | HTML iconHTML  

    In order to measure high current (several tens of kilo Ampere) at low temperature (down to 4.2 K), we have developed collaboration with Hitec Power Protection (Netherlands ex. Holec). This company sell the Macc+ (a low cost Direct Current Control Transformer) which measures up to 600 A (AC and DC) at 300 K. Several limitations of the standard Macc+ will be pointed out to find the adapted solutions for the different user conditions (temperature, current level and background magnetic field). With some minor modifications to the standard produce, we could place the torus sensor at low temperature and we measured up to RA in liquid helium at low field. Analysis of the behavior of the device in nonstandard conditions and experimental results will be reported. With more modifications, we could measure up to 38 kA at 4.2 K in a 0.5 T-background magnetic field. View full abstract»

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  • Recent progress in the development of ultra high strength "continuous" Cu/Nb and Cu/Ta conductors for non-destructive pulsed fields higher than 80 T

    Publication Year: 2002 , Page(s): 1181 - 1184
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (197 KB) |  | HTML iconHTML  

    High strength and high conductivity Cu/Nb nanofilamentary wires are elaborated for the winding of resistive coils that produce pulsed high magnetic fields. The structure of the "continuous" Cu/Nb nanocomposites is a Cu matrix containing continuous parallel Nb filaments with a diameter in the nanometer range. The best first generation conductors possessed at 77 K an ultimate tensile strength of 2 GPa and a resistivity of 0.6 μΩ.cm for a 0.04 mm2 section. The aim of this work was to link the macroscopic properties to the structure at the nanometer scale in order to define an optimized geometry. Structural studies and in-situ tensile tests in a transmission electron microscope revealed the effect of confinement on the plasticity of the finest Cu channels and of the Nb nanowires. The effect of the nanometer size was modeled to predict the mechanical and the electrical properties. The good agreement between the simulations and the experimental data allowed the definition of the optimization parameters that were used to elaborate the new generation continuous Cu/Nb nanocomposites: the best result was achieved for a Cu/28% vol. Nb conductor with a 5 mm2 section, containing 52.2×106 Nb nanofilaments with a diameter of 140 nm: at 77 K, the UTS is 1.9 GPa and the resistivity is 0.58 μΩ.cm. These optimized reinforced conductors can be used to build a pulsed coil generating fields higher than 80 T in a coilin-coilex system. The continuous nanocomposites are further improved by the following two ways: (i) increasing the number of Nb nanowhiskers to 855=4.4×109; (ii) using other b.c.c. reinforcing metals with higher shear modulus (tantalum). An innovating and promising structure is also under development: the "co-cylindrical" Cu/Nb/Cu nanocomposites, where the Cu matrix contains 85n Nb nanotubes filled with Cu nanowhiskers. View full abstract»

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  • Contribution of iron yoke on helical coils [for RHIC]

    Publication Year: 2002 , Page(s): 1479 - 1482
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    In order to estimate the field contribution due to an axially symmetric iron yoke for a helical magnet, a three-dimensional magnetic scalar potential problem with helical symmetry is solved. It is confirmed that the asymptotic forms for potential and field coincide with those for the two-dimensional magnet, in the limit of large twist pitch length. Then, it is also confirmed that the obtained analytical expression for the magnetic field is consistent with the numerical field calculation. View full abstract»

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  • Influence of inlet pressure and mass flow rate on the temperature rise of superconducting strands in SSTF under the normal operating conditions [of KSTAR]

    Publication Year: 2002 , Page(s): 1541 - 1544
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (213 KB) |  | HTML iconHTML  

    In order to estimate the operating characteristics of the main coils, blip and compensating coils of SSTF (Samsung superconducting test facility) which will be operated under the pulsed field to simulate the operating scenarios of KSTAR (Korean Superconducting Tokamak Advanced Research), an analysis has been performed to study the influence of cryogenic parameters, such as inlet temperature, pressure and mass flow rate on the temperature margin for the main, blip and compensating coils. The temperature margin is studied under the given operating scenarios. The reduction of mass flow rate and peak temperature rise, which are strongly depending on the inlet pressure and inlet position of supercritical helium in the CICC are studied. It is noticed that the initial mass flow rate remarkably influences on the peak temperature of superconducting strands. The large mass flow rate can reduce the temperature rise when the helium inlet is installed at the high field region. On the other hand, the small initial mass flow rate results in the low peak temperature in strands when the helium inlet is located at the low field region, since the heat induced flow occurs to improve the cooling condition of the superconducting strands. View full abstract»

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  • Trapped field characteristics of Y-Ba-Cu-O bulk in time-varying external magnetic field

    Publication Year: 2002 , Page(s): 820 - 823
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (234 KB) |  | HTML iconHTML  

    It is very important to clarify characteristics of trapped field in HTS bulk exposed to an external AC magnetic field in application of high-temperature superconducting bulk to motors, magnetic levitation systems, bulk magnets and so on. We have experimentally investigated the transition of trapped field while applying external AC magnetic field to a disk-shaped YBCO bulk. The observed trapped-field attenuation is different from that by flux creep, i.e., zero external field. It may be considered that the trapped-field attenuation is affected by external AC magnetic field, particularly temperature rise due to AC loss. In this paper, electromagnetic behavior within the bulk exposed to external AC magnetic field, especially supercurrent distribution, are investigated numerically using a simulation code based on the finite element method (FEM) considering voltage-current (E-J) characteristic. We focus on the relationship between the transition of supercurrent distribution within the bulk while applying external AC magnetic field and both n-value of E-J characteristic and temperature rise by AC loss. View full abstract»

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  • Basic characteristic evaluation of cryocooler-cooled HTS coils

    Publication Year: 2002 , Page(s): 766 - 769
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (193 KB) |  | HTML iconHTML  

    To survey the applicability of existing HTS wires for SMES, five kinds of cryocooler-cooled HTS coils were fabricated and tested to estimate fundamental characteristics of HTS wires. Critical current, run-away current, and ac losses were measured. To confirm the effect of electromagnetic force to the coil performances, critical currents were measured under high magnetic fleld of 14 T with liquid helium cooling. The HTS wires used for the coils are three types of Bi2212 wire and two types of Bi2223 wires. We have wound these wires to little coils of 14 cm outside diameter, 10 cm height with cryocooling. As a result, a difference of critical current characteristic of a Bi2212 wire and a Bi2223 wire was not big at the temperature of 20 K, but a critical current of a Bi2212 wire fell at 50 K greatly, and the HTS-SMES design that utilized a temperature margin by cryocooler-cooled system understood what a Bi2223 wire was suited for. View full abstract»

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  • Analysis of conductor displacements in the coil of the LHC main dipole by speckle interferometry

    Publication Year: 2002 , Page(s): 1709 - 1712
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (208 KB) |  | HTML iconHTML  

    Magnetic field quality in superconducting magnets mostly depends on the conductor position in operational conditions (under pressure, at 1.9 K). For the case of the LHC main magnets, the conductor layout must agree with the nominal design within less than 0.05 mm to met the field quality specifications. Finite element models are a numerical tool to forecast loads and deformations of mechanical structures, and can be used to evaluate conductor displacements. To verify the FEM response at room temperature, we made displacement measurements using speckle interferometer on a short sample of the dipole coils. Experimental results are compared with the numerical calculations, allowing a stringent test of the most critical features of the FEM (interfaces between different materials and coil properties). View full abstract»

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IEEE Transactions on Applied Superconductivity contains articles on the applications of superconductivity and other relevant technology.

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Meet Our Editors

Editor-in-Chief
Britton L. T. Plourde
Syracuse University
bplourde@syr.edu
http://www.phy.syr.edu/~bplourde