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LARGE SCALE SESSIONS Plan with Mix 100 Km/H Speed, Which Will Be the First Step of HTS Maglev Engineering

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design. Besides, a low-mid speed HTS Maglev test line is being on the LARGE SCALE SESSIONS plan with mix 100 km/h speed, which will be the first step of HTS Maglev engineering. This work is supported by the National High Technology Research and Development Program of China (2007AA03Z210, 2007AA03Z207) and MONDAY, AUGUST 18, 2008 National Natural Science Foundation in China (50677057, 50777053). 11:00am MONDAY MORNING ORAL SESSIONS 1LA03 - Relaxation transition due to different cooling processes in a 10:30am - 12:30pm superconducting levitation system X.Y.Zhang, Y.H.Zhou, J.Zhou, Lanzhou University Relaxation of levitation force in a high-temperature superconducting levitation system is well known to be unavoidable based on the flux 1LA - Maglev, Bearings and Flywheels – I 10:30am - 12:15pm creep phenomenon. In this work, an updated high-temperature superconductor maglev measurement system was used to measure the 10:30am relaxations of levitation force and lateral force due to different cooling 1LA01 - Theoretical Hints for Optimizing Force and Stability in processes simultaneously. The effects of the cooling processes on the Actual Maglev Devices relaxations in both the levitation force and lateral force are remarkably N.Del-Valle, A.Sanchez, C.Navau, Universitat Autonoma Barcelona; observed in the present experiment, and transition phenomena are also D.X.Chen, ICREA and Universitat Autonoma Barcelona found in the relaxation and the force behaviors (i.e., either attraction or The achievement of high-quality high-temperature bulk superconductors repulsion) to both the levitation force and the lateral force. An updated has created much interest in maglev technology not based on magnets frozen-image is used to calculate the relaxations in the levitation force made of superconducting filaments but instead on the use of bulk and lateral force due to different cooling height, the results agree with material as levitating agents. In principle, large levitation forces with the experimental results qualitatively. Our results provide the basis for stability against small perturbations can be achieved in bulk improving the design of high temperature superconductor levitation superconducting material levitating in the presence of external magnetic devices. fields. But the actual force and stability depends strongly on the details This work is supported by the Fund of Natural Science Foundation of of the particular arrangement of the superconductor and magnetic parts China (No. 10472038), the Fund of Ministry of Education of the and other effects (such as field-cooling and working distances). Here we Program of Changjiang Scholars and Innovative Research Team in review some of our recent theoretical calculations of force and stability University (No. IRT0628), the Science Foundation of the Ministry of [APL 90, 042503 (2007); 91, 112507 (2007); 92, 042505 (2008)] and Education of China for Ph. D program. The authors gratefully present some new ones, using a realistic model based on energy acknowledge this financial support. minimization in the superconductor, assuming a general magnet- superconductor system with translational symmetry. From the calculated 11:15am results we provide to actual device designers with hints of how to 1LA04 - Magnetic Levitation Upgrade to the Holloman High Speed optimize either the levitation force, or the stability or a combination of Test Track both, how to choose the field-cooling distance to satisfy each Y.Hsu, D.Ketchen, L.Holland, D.Doll, General Atomics; A.Langhorn, application, and how to realize less reduction of the levitation force after Startech, Inc.; D.Minto, U.S. Air Force a lateral displacement of the superconductor. The MagLev Upgrade program at Holloman AFB, NM started in 1994 with the goal of providing a low vibration payload environment 10:45am compared to the existing slipper on rail rocket sled system. The sled is 1LA02 - Recent development of high temperature superconducting propelled by solid fuel rocket motors. During sled motion, the field from Maglev system in China superconducting magnets mounted on the sled interacts with passive J.Wang, S.Wang, J.Zheng, Applied Superconductivity Laboratory, copper rails embedded in a concrete guideway to produce levitation and Southwest Jiaotong University flight stability. Five flight tests have been conducted so far with the most After the man-loading high Tc superconducting Maglev demonstrations recent reaching 423 mph, setting the world speed record for a have been tested successfully, its future application attracts more and magnetically levitated vehicle. This will increase to beyond supersonic more researchers and engineers. The paper will review the recent speed as more guideway is built during the next few years. The magnets development of HTS Maglev system in China, which is one of three consist of racetrack coils, which are wet lay-up wound with rectangular representative research groups. In the past seven years, dynamic force NbTi wire. They were tested to 245A with a peak field of 7T and and running performance have been studied based on static force winding current density of 38kA/cm2. The coils are bath cooled in one performance by three HTS magnetic levitation (maglev) measurement liter LHe volume helium vessels. A passive valving system prevents loss series and 11-ch vibration measurement apparatus. For the further of liquid during rapid acceleration and deceleration. Boil-off gas cools engineering application of HTS Maglev train, some practical conditions an aluminum thermal shield which operates at about 25K, this gas also are considered in details, like inhomogeneous magnetic field along the cools the current leads. In flight tests, the magnets are cooled from room forward direction, thermal dissipation, restorable guidance capability temperature with LHe through an attached umbilical line. Cooldown and so on. On the other hand, a systemic simulation method is presented time is about two hours. The magnets are charged to 210A and placed to analyze or optimize the origin high temperature superconductor and into persistent mode. The cooling circuit and power leads umbilical are permanent magnetic guideway system. Primary running parameters or remotely disconnected immediately prior to launch. A flight lasts about notes are obtained for the future practically safe HTS Maglev system five seconds, the magnets quench due to lack of liquid after about 20 minutes. 11:30am The accompanied scaling of the electric power unit to 400 kW meets 1LA05 - Design for Field Deployable Flywheel with High- requirements of industrial use. It allows studying market and Temperature Superconducting Bearings commercialization conditions by modernizing local electricity M.Strasik, P.E.Johnson, J.R.Hull, J.Mittleider, J.F.Gonder, infrastructure. K.E.McCrary, C.R.McIver, The Boeing Company Support by the German Ministry of Education and Research under the A design is presented for a small flywheel energy storage that is contract number 13N8737/38 is acknowledged. deployable in a field installation. The flywheel is suspended by high- temperature superconducting (HTS) bearings that are conduction cooled by connection to a cryocooler. At full speed, the flywheel has 5 kWh of 1LB - Power Transmission Cables – I 10:30am - 12:30pm kinetic energy, and it can deliver 1 kW of three-phase 208 V power to an electrical load. The entire system, which includes an S-bracket 10:30am containment structure, is compatible with transportation by forklift or Invited crane. Design options to minimize the parasitic loads due to vacuum, 1LB01 - Installation and Testing Results of Long Island cryogenic, and power electronics are presented. Laboratory Transmission Level HTS Cable measurements of the bearing loss are combined with the parasitic loads J.F.Maguire, J.Yuan, American Superconductor; F.Schmidt, Nexans; to estimate the roundtrip efficiency of the system. S.Bratt, Air Liquide; T.E.Welsh, LIPA This work was supported by the U.S. Department of Energy, Sandia The first long length, transmission level voltage, cold dielectric, high National Laboratories Energy Storage Program Contract 598172 temperature superconductor power cable has been successfully installed in the Long Island Power Authority (LIPA) grid. The cable is capable of 11:45am carrying 574 MVA at a voltage of 138 KV. Three 600m long phase 1LA06 - High Rotational-Rate Rotors with High-Temperature conductors were manufactured and shipped to the LIPA site. The Superconducting Bearings installation process included pulling three cables through three separate J.R.Hull, M.Strasik, J.Mittleider, J.Gonder, P.Johnson, K.McCrary, 600m long underground conduits and assembly of three terminations at C.McIver, Boeing each end. The project has been funded by the US Department of Energy Improvements in high-strength fibers are expected to enable the and is led by American Superconductor. The project team is comprised operation of flywheels with very high rim velocities. Small versions of of Nexans, Air Liquide and LIPA. This paper will describe the system, such flywheels will be capable of very high rotational rates and will installation process, an overview of various testing results before and likely require the low loss inherent in high-temperature superconducting after installation. In addition, details of an initial successful cool-down (HTS) bearings to achieve these speeds. The behavior of these bearings process will be presented. It will also include the performance results in at high rotational rates has hitherto
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