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Heat conduction load test is a main and tough issue in the complex and huge general atom (GA) feeder system cold test. The GA feeder system is a superconducting system connects from the room temperature power supply system to the 4.5-K busbar of the magnet, supply 52 kA current and cryogenic provisions to the central solenoid magnet (CSM) coil, used for International Thermonuclear Experimental Reactor CSM magnet test at General Atomics Company, San Diego, CA, USA. This system have been developed and constructed at the Institute of Plasma Physics, Chinese Academy of Sciences, and completed the full cold test before transferred to the USA. In all the cold test items, the requirement of overall heat load 68 W is a big challenge, for its many leakage heat sources and cooling circuits: high temperature superconducting current lead, vacuum barrier, busbars, pipes, supports, etc. In order to get the steady results, many efforts were took to achieve the required value, such as reduce the inlet pressure of the 5-K loop as much as possible, minimize the flow rate of different 5-K cooling circuits, and at the same time, a dedicated program was developed to online calculate the density and the heat load while monitoring and analyzing the heat load. This paper will give a detail description of the 5-K overall heat load measurement. [ABSTRACT FROM AUTHOR]

In 1966, following a decade of discovery and development on A15 compounds, Richard Garwin and Juri Matisoo [1], two research staff members then in the IBM Research Division, submitted for publication a paper examining the prospect to employ one of the most promising of these materials, Nb3Sn, in a cable system for transmission of electricity. The scale of their proposal was truly enormous -100 GW (+/-100 kV at 500 kA direct current) over a distance of 1000 km, the entire length refrigerated by liquid helium. At the time, such a cable would have been capable of carrying half the entire electric power generated in the United States, and about one-tenth today. This paper will revisit their vision in the context of the subsequent discovery of high temperature superconductivity twenty years later, and the now emerging availability of long lengths of high performance wire and tape for operation in the 20–80 K range. Whereas the scenario set by Garwin and Matisoo addressed the one-way transmission of electricity from remote coal and nuclear generation multi-plant ‘farms’ to large population centers, we will extend their picture to include two-way transmission on a diurnal or longer period to take advantage of regional electricity pricing and production which has resulted from the deregulation of generation. We conclude that the advent of high temperature superconductivity substantially extends and brings closer both the technical and economic feasibility of Garwin and Matisoo's dream. However, we note, as did they, the caveat that ‘whether it is desirable or necessary is another matter entirely.’ We believe this question will be decided in the affirmative as societal demands continue to increase for the clean, reliable and ecologically gentle delivery of large amounts of electric power, a need that was foreseen but not as overriding forty years ago as it is now. [ABSTRACT FROM AUTHOR]

The United States ITER Project Office (USIPO) is responsible for fabrication of the Central Solenoid (CS) for International Thermonuclear Experimental Reactor (ITER). The CS Insert (CSI) project should provide verification of the conductor performance in relevant conditions of temperature, field, currents and mechanical strain. The USIPO will build the CSI that will be tested at the Central Solenoid Model Coil (CSMC) Test Facility at JAEA, Naka, Japan. This paper presents three-dimensional mathematical model of CSI based on the design. Simulations were performed in order to verify structural integrity and compliance with the Japanese High Gas Pressure Safety Law. Numerical simulations lead to the design of the CSI that produced a required strain levels during operation on the superconductor cable, while simultaneously satisfy the ITER magnet structural design criteria. [ABSTRACT FROM PUBLISHER]

The use of high temperature superconducting (HTS) tapes in a flexible cryostat has been shown to provide great opportunities for the US Navy. The HTS tapes need to be fixed at the ends to provide an electrical connection. Since the ends are rigid but the tapes are contained in a changing environment there is a possibility that the tapes may become twisted and therefore damaged. Twisting is defined in this paper as the rotation of the tape along the length of the tape while the end has no attack-angle. The twisting length and angle of first generation (1G) BSCCO tapes is studied by measuring the voltage drop across the tapes in a liquid nitrogen bath when current is applied. [ABSTRACT FROM AUTHOR]

This paper discusses the full-power testing of a 36.5 MW High Temperature Superconductor (HTS) propulsion motor at the Navy's Land Based Test Site (LBTS) located in Philadelphia, PA. This motor was developed under funding from the Office of Naval Research and passed no-load factory testing at Philadelphia in March 2007. The Naval Surface Warfare Center (Carderock Division - Philadelphia site) designed and installed a test facility at LBTS to support full-power/full-torque testing of the HTS motor delivered to the Navy in 2007. The facility, test plan and full-power and full-torque test results of the HTS propulsion motor are presented. These test results provide the final substantiation that this technology is ready for integration in to a Navy electric drive combatant. [ABSTRACT FROM AUTHOR]

The US Department of Homeland Security is currently funding the design, development and demonstration of an inherently fault current limiting HTS cable, called Secure Super Grids, under the Hydra project with Con Edison. The cable is 300 m long and is being designed to carry 96 MVA at a distribution level voltage of 13.8 kV. The cable will be built using cable system experience gained by AMSC and Ultera (a Southwire and nkt Cables joint venture) on previous projects. The underground cable will be permanently installed and energized in New York City in 2010. The project is led by American Superconductor who is teamed with Ultera and Con Edison. This paper describes the general goals and design criteria of the project. An overview of the concept of Secure Super Grids and advantages of this type of cable are presented in a grid-based network modeling. In addition, the design issues such as tailoring of the HTS wire to provide adequate thermal stability and electrical properties both under normal operation and during a fault are presented. [ABSTRACT FROM AUTHOR]

High-temperature superconducting (HTS) cable systems are expected to be a solution for improvement of the power grid and three demonstration projects in the real grid are underway in the United States. One of these is the Albany, NY HTS Cable Project, involving the installation and operation of a 350 meter HTS cable system with a capacity of 34.5 kV, 800 A, installed between two substations in National Grid's electric utility system. A 320 meter and a 30 meter cable are installed in an underground conduit and connected together by a joint, or splice in a vault. In Phase I of this project, the cables were fabricated with DI-BSCCO wire in a 3-core-in-one cryostat structure. After the installation of the HTS cable system, the in.grid operation began on July 20, 2006 and operated successfully in unattended condition through May 1, 2007. In Phase II, the 30 meter section was replaced by a 2G (YBCO) cable. The 2G cable was fabricated with SuperPower's YBCO coated conductors in a 3 core-in-one cryostat. After replacement of the 30 meter section, the joint and one termination were reassembled and the commissioning tests that included initial cooling, critical current measurement and DC withstand voltage test were completed successfully. After the commissioning tests, the HTS cable system with a 30 meter YBCO cable and a 320 meter DI-BSCCO cable was re-energized on January 8, 2008 and started again to operate in a live utility network. This paper describes the latest status of the Albany HTS cable project. [ABSTRACT FROM AUTHOR]

The first long length, transmission level voltage, cold dielectric, high temperature superconductor power cable has been successfully installed in the Long Island Power Authority (LIPA) grid. The cable is capable of carrying 574 MVA at a voltage of 138 Ky. Three 600 m long phase conductors were manufactured and shipped to the LIPA site. The installation process included pulling three cables through three separate 600 m long underground conduits and assembly of three terminations at each end. The project has been funded by the US Department of Energy and is led by American Superconductor. The project team is comprised of Nexans, Air Liquide and LIPA. This paper describes the cable system, installation process and an overview of various testing results before and after installation. In addition, details of an initial successful cool-down process are presented. It also includes the performance results in grid operation. [ABSTRACT FROM AUTHOR]

The US National High Magnetic Field Laboratory constructed and tested a stand-alone 80 T prototype magnet. The activity was in support of the insert magnet development project for the US-DOE-NSF 100 Tesla Multi-Pulse Magnet Program. The 80 T magnet assembly was developed to simulate the physical conditions an insert magnet would encounter during peak field operations at 105 T… The design incorporated further improvements to the engineering template developed from the 65 T and 75 T pulsed magnets now in use at the NHMFL Pulsed Field Facility at Los Alamos National Laboratory. Two coaxially nested solenoid coils comprised the 80 T prototype magnet design. The windings are in series electrically. The inner coil is constructed with materials & techniques identical to those in use for the 100 T insert program. The outer coil is a conventional winding. The prototype was successfully trained to a peak field of ~80.4 T. 80 T pulsed operations were repeated until the coil assembly faulted after 10 full-field pulses. Post-fault inspection of the magnet assembly indicated that the outer magnet winding failed structurally. This paper will present an overview of the 80 T prototype's design, construction, and performance. A review of the magnets failure mode will be presented. Additionally, we will discuss new design criteria for stand alone high-field pulsed magnet based upon the 80 T prototype experience. [ABSTRACT FROM AUTHOR]

The U. S. National High Magnetic Field Laboratory 100 Tesla Multi-Pulse Magnet System is now successfully commissioned. This magnet system is the result of a long-term partnership project jointly funded by the U. S. Department of Energy-Office of Basic Energy Science and the National Science Foundation. Science experimentation inside the magnet started in December 2006 at the NHMFL Pulsed Field Science Facility located at Los Alamos National Laboratory. Repeated, non-destructive operation of the system with original components is continuing in the 85 T to 90 T range. The system will eventually combine, a nominal 40 T platform field produced by a controlled-waveform generator-powered long-pulse magnet with a nominal 60 T field generated by a capacitor-bank powered pulsed insert magnet to produce the rated field. Milestone non-destructive operation to 88.9 T was achieved in October 2006. This paper will present an overview of the generator driven outsert magnet system together with the high-field pulsed insert magnet's design and construction. We will review commissioning and performance data through summer of 2007. Criteria for increasing the systems maximum field performance will also be reviewed addressing the goal to increase operating field level (in support of experiments) to 95 T and then to 100 T. [ABSTRACT FROM AUTHOR]

The National High Magnetic Field Laboratory (NHMFL) has embarked on an innovative program to develop a number of Series-Connected-Hybrid magnetic systems. In this novel concept, a set of resistive coils (insert) and a set of superconducting cable-in-conduit conductor (CICC) coils (outsert) are electrically driven in series, rather than independently as in previous hybrid systems. Presently NHMFL is working on 3 different projects. The first, funded by the National Science Foundation (NSF) with an $11.7 million grant, is related to the construction of a cylindricel-bore Series-Connected Hybrid (SCH), for high field nuclear magnetic resonance (NMR), condensed matter physics, biology and chemistry, to be located at the Magnet Lab's Tallahassee location. The second, funded by the Hahn-Meitner Institute (HMI) in Berlin, relates to the engineering design for a horizontal bore Series-Connected Hybrid to be used in a neutron diffraction experimental system. Finally, the third, also funded by NSF, is a conceptual and engineering study for an SCH that would be used for neutron scattering experiments at Oak Ridge National Laboratory's Spallation Neutron Source (SNS), similar to the HMI version. Because of the main points in common between the 3 different systems, our final goal is to develop a superconducting magnetic system suitable for the 3 applications. We believe this is possible for the magnet although, due to the different field/bore orientations, some differences in the mechanical design of the cryostat and resistive inserts will exist. In this paper we will give an overview of the R&D strategy devised to develop these superconducting magnetic systems, together with a report on the present status of such program. [ABSTRACT FROM AUTHOR]

In support of the development of a large-aperture Nb3Sn superconducting quadrupole for the Large Hadron Collider luminosity upgrade, two models (TQS and TQC) with a 90-mm aperture are being constructed at LBNL and FNAL within the framework of the US LHC Accelerator Research Program (LARP). These models use two identical Nb3Sn coils but have different coil support structures. This paper describes the fabrication, assembly, cool-down and test of TQS01—a model based on key and bladder technology with supporting iron yoke and an aluminum shell. Comparison of the test measurements with design expectations is also reported. [ABSTRACT FROM AUTHOR]

The COHMAG report of the National Academy of Sciences provides an assessment of high field magnet science and technology in the United States, and identifies possible new initiatives for future high field magnets. Regarding NMR, the report identifies high resolution NMR spectrometers in the range of 30 T/1.3 GHz as having great scientific interest. This paper discusses technology issues associated with 30 T superconducting magnets. The enabling technology is HTS conductors and coil technology. Significant issues remain for application of HTS conductors to large coils, including long length quality, heat treatment, anisotropy and strain dependence. The outer LTS coil sections are large, with high stress and stored energy. Structural issues, including high strength conductor and reinforcement, and quench protection issues are significant. The status of technology required for a 30 T NMR magnet is examined. A preliminary conceptual design of the 30 T magnet is presented. [ABSTRACT FROM AUTHOR]

The US LHC Accelerator Research Program (LARP) is developing Nb3Sn accelerator magnet technology for the LHC luminosity upgrade. Two 90 mm ‘Technology Quadrupole’ models (TQS01, TQC01) are being developed in close collaboration between LBNL and FNAL, using identical coil design, but two different support structures. The TQS01 structure was developed and tested at LBNL. With this approach coils are supported by an outer aluminum shell and assembled using keys and bladders. In contrast, the second model TQC01, utilize stainless steel collars and a thick stainless steel skin. This paper describes the TQS01 model magnet, its 3D ANSYS stress analysis, and anticipated instrumentation and assembly procedure. [ABSTRACT FROM AUTHOR]

As a first step toward the development of a large-aperture Nb3Sn superconducting quadrupole for the Large Hadron Collider (LHC) luminosity upgrade, two-layer technological quadrupole models (TQS01 at LBNL and TQC01 at Fermilab) are being constructed within the framework of the US LHC Accelerator Research Program (LARP). Both models use the same coil design, but have different coil support structures. This paper describes the TQC01 design, fabrication technology and summarizes its main parameters. [ABSTRACT FROM AUTHOR]

This paper presents results of design studies of high-field dipole magnets based on Nb3Sn shell-type coils performed to explore the possibilities and limitations of Nb3Sn accelerator magnets. To achieve the maximum bore field of 13–16 T, 3- and 4-layer coils were used. The coil design concepts, conductor parameters, results of magnetic and mechanical analysis are presented and discussed. Different conductor grading techniques are described and compared. An innovative design of a 3-layer coil without interlayer splices is described. [ABSTRACT FROM AUTHOR]

Over the last few years, several novel magnet designs have been introduced to meet the requirements of new, high performance accelerators and beam lines. For example, the FAIR project at GSI requires superconducting magnets ramped at high rates (∼4 T/s) in order to achieve the design intensity. Magnets for the RIA and FAIR projects and for the next generation of LHC interaction regions will need to withstand high doses of radiation. Helical magnets are required to maintain and control the polarization of high energy protons at RHIC. In other cases, novel magnets have been designed in response to limited budgets and space. For example, it is planned to use combined function superconducting magnets for the 50 GeV proton transport line at J-PARC to satisfy both budget and performance requirements. Novel coil winding methods have been developed for short, large aperture magnets such as those used in the insertion region upgrade at BEPC. This paper will highlight the novel features of these exotic magnets. [ABSTRACT FROM AUTHOR]

In 2004, the US DOE established the LHC Accelerator Research Program (LARP) with the goal of developing a technology base for future upgrades of the LHC. The focus of the magnet program, which is a collaboration of three US laboratories, BNL, FNAL and LBNL, is an development of high gradient quadrupoles using Nb3Sn superconductor. Other program components address issues regarding magnet design, radiation-hard materials, long magnet scale-up, quench protection, fabrication techniques and conductor and cable R&D. This paper presents an overall view of the program with emphasis on the current quadrupole project and outlines the long-term goals of the program. [ABSTRACT FROM AUTHOR]

The present Alternating Gradient Synchrotron (AGS) injection kicker magnets at the A5 location were designed for 1.5 GeV proton injection. Recent high intensity runs have pushed the transfer kinetic energy to 1.94 GeV, but with an imperfect matching in transverse phase space. Space charge forces result in both fast and slow beam size growth and beam loss. A proposed increase in the AGS injection energy to 2 GeV with adequate kick strength would greatly reduce the beam losses making it possible to increase the intensity from 70 TP (70 × 1012 protons/s) to 100 TP. R&D studies are being undertaken by TRIUMF, in collaboration with Brookhaven National Laboratory (BNL), to design two new kicker magnets for the AGS A10 location to provide an additional kick of 1.5 mrad to 2 GeV protons. The kick strength rise and fall time specifications are 100 ns, 3% to 97%; the design goal is to achieve a field uniformity, for protons, of ±3% over 90% of the cross-sectional area of the aperture. TRIUMF has proposed a design for a 12.5 Ω transmission line kicker magnet powered by a matched 12.5 Ω pulse forming line. This paper presents the results of detailed 2D and 3D electromagnetic modeling of the kicker magnet, and a novel mathematical model of the kicker. [ABSTRACT FROM AUTHOR]

NASA conducts and funds research to advance the state of the art in aeronautics, including improvements in aircraft design leading to enhanced performance in areas such as noise, emissions, and safety. A particular initiative involves development of an all-electric aircraft requiring significant improvements in certain technologies. NASA has started a new project with one of the objectives being the development of enabling technologies for an all-electric aircraft. Electrical aeropropulsion requires the design of more compact and efficient electrical motors. In order to me crease the power density, the weight/size must be minimized and the air gap flux density must increase significantly the use of superconducting materials is an obvious choice. Existing HTS motors are proof-of-principle demonstrators and exhibit power densities lower than 1 HP/lb, which is too low to be considered in mobile systems. This paper deals with a preliminary electromagnetic design of a 200 HP high temperature superconducting motor optimized in terms of power density. The presented configuration is a synchronous motor with a nonconventional topology enhanced by HTS bulk material. The design targets the Cessna 172 propulsion requirements that are 200 HP at 2700 RPM. [ABSTRACT FROM AUTHOR]

The article announces the Van Duzer Prize, which is sponsored by the Institute of Electrical and Electronic Engineers (IEEE) Council on Superconductivity for the best contributed paper in the U.S. The award aims to encourage authors to prepare well written and comprehensive contributions with archival values. It mentions the 2006 Van Duzer Prize recipients for their paper titled "Incorporation of a Frequency-Dependent Dielectric Response for the Barrier Material in the Josephson Junction Circuit Model."