ORAL SESSION 3D4: Applications

Wednesday, Feb. 23, 10:00 a.m. – 12:00 p.m., Room 301F (GRB)

Chairs: C. Platt (ATP/NIST), P.M. Grant (EPRI)

3D4.1 HTS Power Technologies: Nanometers and Megawatts

J. G. Daley, U. S. Department of Energy

Presenting Author: J. G. Daley

Progress in high temperature superconductivity (HTS) power applications is measured by improved material properties for electrical wires at the atomic scale as well as by capacity improvements of large scale electrical system prototypes that need to handle 10s of megawatts in most applications. Simultaneously addressing issues of the entire innovation cycle has offered opportunities for compressing the time normally needed from discovery to initial demonstration. The time to achieve full utilization of this new capability is also being compressed by simultaneously developing a portfolio of important applications - including transformers, transmission cables, motors, and current controllers. The present status and implications for the future are discussed.

3D4.2 R&D of Coated Conductors in Japan

Yuh Shiohara. Superconductivity Research Laboratory, ISTEC 1-10-13 Shinonome, Koto-ku, Tokyo, 135-0062 Japan

Presenting Author: Y. Shiohara

RE-123 (RE: Y, Sm, Nd…) superconductive oxides have been expected to be utilized for electric conductors due to its high performance of superconductivity and high critical currents under high magnetic fields at 77 K. Immediate objectives and problems to be solved in the R&D of coated conductors are the followings; (i) in-plane alignment of the superconductive grain orientation in a thick film, (ii) achievement of higher production rate without degradation of the superconductivity performance, (iii) strengthening of metallic substrates and application of thinner and non-magnetic metallic substrates, (iv) production of thicker superconductive films with maintaining high J_c to attain higher J_c, (v) development of non-vacuum processes such as Liquid Phase Epitaxy (LPE) and Metalorganic Deposition (MOD), (vi) development of Sm-123 and Nd-123 coated conductor processing, and (vii) production of long coated conductors (>100m) to demonstrate the applicability of the performance of the coated conductors such as electric cable, current limiter and superconductive magnets. The R&D of the coated conductors has started in Japan as a national project with collaboration of electric power companies, wire & cable production companies and SRL-ISTEC. In this presentation, current status and goals of the project and the variety of the processes to be examined will be reviewed.

This work is supported by the New Energy and Industrial Technology Development Organization (NEDO) as Collaborative Research and Development of Fundamental Technologies for Superconductivity Applications.

3D4.3 Naval Applications of Superconducting Magnet Systems

Donald U. Gubser, Naval Research Laboratory, 4555 Overlook Ave., Washington, DC 20375

Presenting Author: D.U. Gubser

The US Navy continues to pursue exploratory development of systems incorporating superconducting magnets. Such systems fall into three main categories: motors, energy storage, and magnetic signatures. Motor development is primarily for ship propulsion systems (<25,000 hp) and includes both high temperature superconducting (HTS) magnets used in ac synchronous machines and low temperature superconductors (LTS) used in dc homopolar machines. Key to both types of motors is conduction (liquid-less) cooling of the magnet system. Superconducting magnets for energy storage (SMES) have been proposed as advanced electromagnetic aircraft launch systems. The Navy is committed to replacing the steam driven launch system in future aircraft carriers and SMES is one alternative. These systems will be large, LTS, liquid helium cooled systems. The third key application of superconducting magnets is to provide a magnetic signature that mimics a ship in order to prematurely explode mines and thereby sweep a clear path for the following ships. Both small HTS and larger LTS magnet systems are under development. In both cases, the magnets are conduction cooled. Key to this application is shock and vibration resistance of the magnet and dewar system. Driving these superconducting developments is a long term Navy strategy that utilizes electrical power to improve operating efficiency and reduce manpower while providing technological superiority. An update of Navy research and development on these three superconducting magnet development projects as well as related research will be presented.

3D4.4 Preliminary Study of Superconducting Bulk Magnets for Maglev

Hiroyuki Fujimoto and Hiroki Kamijo, Railway Technical Research Institute, 2-8-38 Hikari-cho, Kokubunji-shi, Tokyo 185-8540, Japan

Presenting Author: H. Fujimoto

Recent development shows that melt-processed YBaCuO (Y123) or Rare Earth (RE)123 superconductors have a high J_c at 77 K and high magnetic field. Solidification processes for producing RE123 superconductors are effective for obtaiing high J_c, leading to high field application as a superconducting quasi-permanent bulk magnet with the liquid mitrogen refrigeration. One of the promising applications is a superconducting magnet for the magnetically levitated (Maglev) train.

The present preliminary study follows an example of promising applications in Railways. We discuss a superconducting bulk magnet for the Maglev train in the aspect of a preliminary design of the bulk magnet and also melt processing for (L)REBaCuO bulk superconductors and their characteristic superconducting properties.

3D4.5 HTS Activities in Europe: Perspectives for bulk and tape conductors

Herbert C. Freyhardt, Institut fuer Materialphysik, Universitaet Goettingen und Zentrum fuer Funktioinswerkstoffe gGmbH, D-37073 Goettingen, Germany

Presenting Author: Herbert C. Freyhardt

The review will summarize the status of developments of HTS tape and wire as well as bulk conductors in Europe for applications in electrical and power engineering.

3D4.6 Some Requirements of the Petaflop Computer

John M. Rowell, Materials Research Institute, Northwestern University, Evanston, IL

Presenting Author: J. Rowell

A recent proposal to build a petaflop computer within the next decade, has defined the need for an ultra-high-speed IC technology operating at power levels orders of magnitude lower than CMOS. The only candidate technology identified to date for the central processing core of this machine is "second generation" superconducting electronics based on Rapid Single Flux Quantum (RSFQ) logic. The process technology of choice is the niobium/aluminum trilayer Josephson junction process, operating at 4.2K. Assuming that current designs of the petaflop machine are funded, today's technology will have to advance by orders of magnitude. The number of junctions per chip must increase 1000 times, and the clock frequency by about 5 times. The number of fully functional and tested chips required will be a few thousands. Some of the implications of these requirements are that the standard lithography must advance by two generations, while I_cR_n of the junctions will have to be increased, and, to save real estate on the chips, non-hysteretic or internally shunted junctions will be needed. The cryopackage must allow the high speed capabilities of the cold chips to be utilized from room temperature. In addition to describing the improvements needed in today's technology, with emphasis on the materials and junction fabrication process, I will attempt to identify directions of research that, if successful, would enhance the technology both for the petaflops machine, and also for other applications of superconducting digital technology.

3D4.7 HTS in Electric Power Applications, Transformers

Sven P. Hornfeldt, Department of Power Engineering, ABB Corporate Research SE-721 78 Vasteras and Department of Electric Power Engineering, Royal Institute of Technology SE-100 44 Stockholm, Sweden

Presenting Author: S.P. Hornfeldt

With the discovery of the high temperature superconductors (HTS) the prospect to find widespread applications of these conductors also in electric power applications grew very fast. The advantages that could be anticipated was reduced losses, reduced weight and volume plus less environmental impact.

During the last five-six years techniques have been developed to produce long lengths of flexible conductors that can be used in cables or windings. Most manufacturers of HTS concentrated on traditional DC applications. However, much larger markets will open up when good enough AC conductors become available for power applications.

ABB, a producers of power equipment, started -94 a project aiming at a 630 kVA three-phase power transformer with windings made of HTS. This transformer was taken into operation in the spring -97 and operated perfectly for one year.

I will discuss the performance and price demands the HTS has to fulfill to be useful in power applications and review the above mentioned transformer project and also give some insight in a running project with the goal to design, build and put in operation a 10 MVA power transformer with HTS with low AC-losses in the windings.