Kobe Steel, Ltd.

Kabushiki Kaisha Kobe Seiko Sho

Japan Superconductor Technology Inc.

Kyoji Zaitsu

Koji Inoue

Kenichi Inoue

Takayoshi Miyazaki

Hiroyuki Kato

Takayuki Miyatake

Kyoji Tachikawa

Hiroyuki Mitani

Yoshihiro Yokota

Koichi Makii

Hiroshi Hashimoto

Hirofumi Hojo

Eiichiro Yoshikawa

Takashi Hase

Naoya Fujiwara

Akira Tsutsui

Satoshi Ito

Osamu Ozaki

Kazuyoshi Saitou

Satoshi Kizaki

Yukinobu Murakami

Hiroyuki Yasunaka

This DC brushless motor () is provided with a stator () that has exciting coils () and a rotor () that is positioned coaxially to the stator (). The stator () has a quasi-E-shaped cross-section in the axial direction at the radius part; a plurality of protrusions () serving as magnetic poles are formed on the respective 3 parallel sections () of the E in the same number in the circumferential direction; and of the magnetic poles () formed at the 3 parallel sections () of the E, the top and the bottom magnetic poles () are respectively positioned so as to be shifted in the opposite directions in the circumferential direction with respect to the center line of the middle magnetic pole (). Changes in the magnetic resistance between the stator () and the rotor (), which are caused by the flow of a magnetic flux generated around the exciting coils (), are utilized as a driving force. The DC brushless motor () configured in said manner exhibits excellent space efficiency at low cost and is less affected by temperature changes.

DC brushless motor and method for controlling the same

Liquefier includes first compression section which is driven by a superconducting motor and which compresses a substance in a gaseous state. Cooling circuit includes: second compression section which is driven by the motor when first compression section is being driven by the motor and which compresses a refrigerant; first heat exchange section which cools the refrigerant by causing heat exchange between a substance in a tank and the compressed refrigerant; second expansion section which brings the refrigerant down to or below a critical temperature of a superconducting material by expanding the cooled refrigerant; and second heat exchange section which imparts cold heat of the refrigerant to the substance by causing heat exchange between the substance in the tank and the refrigerant after cooling a superconducting magnet, and supplies the refrigerant brought down to or below the critical temperature by second expansion section to the motor and cools the superconducting magnet.

Liquefaction system and power generation system

This heat sink has bonded on one surface a member to be bonded, and has a cooling member in contact with the other surface. The heat sink is provided with a metal plate having a thermal expansion coefficient larger than that of the member to be bonded, and the metal plate is provided with a center portion where the member to be bonded is bonded, and a plurality of linear peripheral slits formed in a whirl-like radial manner such that the linear peripheral slits surround the center portion.

Heat sink and method for manufacturing heat sink

Provided are a multi-phase transformer having an easier-producible structure, and a transformation system wherein a plurality of such transformers are serially connected. Disclosed is a three-phase transformer (Tra) provided with three coils () and a pair of magnetic members () respectively provided on opposite ends in the axial direction of the coils (), wherein the coils () are respectively provided with first and second sub-coils ().

Multi-phase transformer and transformation system

Provided is a reactor that enables high inductance to be generated with stability in a wide current range, while minimizing noise, processing cost, and eddy-current loss. The reactor (D) has the ratio (t/W) of the width (W) to the thickness (t) of a conductive member that composes an air-core coil configured to be 1 or less, and preferably, 1/10 or less. Furthermore, the reactor also has the absolute value of a value ((L&#x2212;L)/L) that has had: the difference (L&#x2212;L) between; the space interval (L) between an inner wall face of a first core member () and an inner wall face of a second core member (), at the innermost circumference position of the air-core coil (); and the space (L) between the inner wall face of the first core member () and the inner wall face of the second core member (), at the outermost circumference position of the air-core coil (); divided by an average value (L); configured to be 1/50 or less. The ratio (R/W) of the radius (R), from the axis-center (O) of the air-core coil () to the outer circumference of the air-core coil (), to the width (W) of the air-core coil () (conductive member), is 2=R/W=4.

Reactor

A precursor for fabricating a NbSn superconducting wire by an internal Sn process includes one or a plurality of stabilizing copper portions collectively disposed in the center, each stabilizing copper portion being provided with a diffusion barrier layer in the periphery thereof, and a superconducting matrix portion disposed so as to surround the one or the plurality of stabilizing copper portions, the superconducting matrix portion including a Nb or Nb-based alloy core and a Sn or Sn-based alloy core embedded in a Cu or Cu-based alloy matrix.

[object Object]

A precursor for manufacturing a NbSn superconducting wire according to the present invention includes a mono-element wire including a Sn or Sn-based alloy core disposed at the, a Cu or Cu-based alloy matrix and a plurality of Nb or Nb-based alloy filaments surrounding the Sn or Sn-based alloy core, and a diffusion barrier layer and a stabilizing copper layer surrounding the Cu or Cu-based alloy matrix. In a final shape after a reduction process, the average diameter of the Nb or Nb-based alloy filaments is set to 5 &#x3bc;m to 30 &#x3bc;m, and the average distance between the Sn or Sn-based alloy core and the Nb or Nb-based alloy filaments nearest the Sn or Sn-based alloy core is set to 100 &#x3bc;m or less.

A method for manufacturing a powder-metallurgy processed NbSn superconducting wire is provided. In the method, a sheath made of Nb or a Nb alloy is filled with a raw material powder containing Sn. The sheath filled with the raw material powder is subjected to diameter reduction to form a wire. The wire is heat-treated to form a superconducting phase at the internal surface of the sheath. The raw material powder is prepared by adding a Sn powder to a Cu&#x2014;Sn alloy powder or a Cu&#x2014;Sn intermetallic compound powder, and is compacted under isotropic pressure.

Disclosed is a manufacturing method of an NbSn superconductive wire using a powder technique, the method including the steps of: filling, as a raw powder, an intermetallic compound powder obtained from a metallic powder containing at least one metallic powder selected from Ta powder and Nb powder, and Sn powder, or a mixture of the metallic powder and the Sn powder into a sheath made of Nb or an Nb based alloy; performing a diameter-reduction process on the sheath to form a wire; heat treating the wire; and, forming a superconductive layer on the interface between the sheath and the powder, wherein at least one of the metallic powders selected from the Ta powder and the Nb powder is obtained by aggregating fine particles (primary) in shape of coral to form secondary particles.

A method for producing an NbSn superconductive wire material using a powder process is provided, in which a powdered raw material is filled in a sheath made of Nb or an Nb-based alloy, and the above sheath is subjected to diameter reduction to form a wire, followed by heat treatment to form a superconducting layer at the interface between the sheath and the filled powder. The above powdered raw material contains powdered Sn, powdered Cu, and a powdered alloy or a powdered intermetallic compound, which is formed from Sn and at least one metal selected from the group consisting of Ti, Zr, Hf, V, and Ta.

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Kobe, Japan

Kyoji Zaitsu