JP2001267119A - Superconducting coil device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a superconducting coil device in which joints between the superconducting lead wires of layers can be lessened in loss, and an electric field hardly concentrates. SOLUTION: A superconducting coil device is possessed of two or more coils which are arranged in layers and each formed through a manner in which a superconducting lead wire 1 is wound on a bobbin 2, where the coils are previously constituted as separate members in layers, and the lead wires of layers are directly connected together at one or more points.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large-sized superconducting coil device applied to, for example, a resistance type current limiting device and the like, and particularly to a reduction in loss when connecting separately manufactured coils of each layer to form a plurality of layers. The present invention relates to a superconducting coil device designed for such purposes.

[0002]

2. Description of the Related Art Conventionally, in a large-sized superconducting coil device configured by winding a plurality of superconducting wires such as a metal-based superconducting wire and an oxide-based superconducting wire, each layer is manufactured individually and independently. Superconducting coils are connected with metal electrodes. This is because, in comparison with a case where a plurality of layers are integrally formed as a whole, it is more manufacturable to manufacture the layers independently.

[0003] Also, a resistance type current limiting device or a PCS
(Permanent Current Switchc
h: permanent power switch), it is desirable to connect layers in the same direction in series in order to shorten the connection part, but in such a case, it is necessary to continuously wind the layers. Since it is difficult, it is common to manufacture each layer independently and connect each layer with an electrode.

FIGS. 6A and 6B are diagrams for explaining the configuration of such a conventional general superconducting coil device.

That is, as shown in FIGS. 6A and 6B,
The coil (n-1 layer) disposed inside is a cylindrical bobbin 2
The coil (n-layer) disposed outside is formed by winding a superconducting wire 7 around a winding frame 6 having a diameter larger than the n-1 layer.

[0006] Each of these coils is manufactured individually, and after manufacture, the ends of the superconducting wires 1 and 7 are connected by a connector (eg, made of copper) 20 having electrodes 19 at both ends as shown in the figure. ing.

[0007]

However, in the above-described superconducting coil device, the electrode portion 19 of the metal-made coupling member 20 made of copper or the like for connecting the superconducting wires 1 and 7 to each other.
In this case, the AC loss increases, and the efficiency of the entire coil deteriorates. In addition, since a projection is formed on the coil, there is a problem that when a high voltage is applied, an electric field is concentrated on a surge voltage.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a superconducting coil device that can reduce the loss of a connection portion between superconducting wires in each layer and that does not easily cause electric field concentration.

[0009]

According to a first aspect of the present invention, there is provided a superconducting coil device having two or more coil portions formed by winding a superconducting wire around a bobbin. Provided is a superconducting coil device, wherein the coil portion is previously configured as an independent member for each layer, and the superconducting wires between the respective layers are directly connected to each other and electrically connected at one or more locations to form a plurality of layers. .

According to the superconducting coil device of the present invention,
By manufacturing each layer independently and electrically connecting the superconducting wires directly, that is, by switchback, the AC loss can be reduced even in a non-inductive coil, and therefore, a metal protrusion can be eliminated.

According to the second aspect of the invention, the superconducting wire of the inner layer is mechanically fixed to the bobbin, and the superconducting wire of the outer layer is electrically connected to a position near the fixed end of the superconducting wire of the inner layer. 2. The superconducting coil device according to claim 1, wherein the superconducting coil device is connected to the superconducting coil device.

According to the superconducting coil device of the present invention,
The superconducting wire of the previous layer is fixed mechanically separately, and the superconducting wire of the outer layer is soldered near the fixing position, that is, at the winding side, so that the mechanical fixing and the electrical connection are separately performed. be able to.

According to a third aspect of the present invention, in the superconducting coil device according to the first or second aspect, the bobbin of the second or higher layer has a notch at a portion where the superconducting wire rises from the inner layer. I will provide a.

According to the superconducting coil device of the present invention,
Since the notch is provided, the winding frame can be covered after the superconducting wire is soldered, and work can be performed without damaging the wire.

According to the fourth aspect of the invention, the curvature diameter of the end of the superconducting wire electrically connected from one layer to a different layer is set so that the strain generated in the superconducting wire is 0.15% or less. A superconducting coil device according to any one of claims 1 to 3, characterized in that:

According to the superconducting coil device of the present invention,
With respect to the radius of curvature of the locus of the superconducting wire extending to the next layer, the generated strain is set to be 0.15% or less, so that the performance deterioration due to the strain can be prevented.

According to the fifth aspect of the present invention, the superconducting wires of each layer are joined by soldering, and the length of the soldering is 1 cm.
The superconducting coil device according to any one of claims 1 to 4, wherein the superconducting coil device is set as described above.

According to the superconducting coil device according to the present invention,
The length for soldering the superconducting wire is sufficient if it is 1 cm or more where the AC resistance hardly changes.

According to the invention of claim 6, the number of layers of the coil portion is three.
The superconducting coil device according to any one of claims 1 to 5, wherein the superconducting coil device has at least two layers.

According to the superconducting coil device of the present invention,
AC loss can be reduced for coils with three or more layers.
Metal projections can be dispensed with.

According to a seventh aspect of the present invention, a fixing base made of a nonmagnetic material for fixing and holding the superconducting wire is provided at a portion where the superconducting wire extends from the inner layer to the outer layer. Item 7. A superconducting coil device according to any one of Items 1 to 6.

According to the superconducting coil device of the present invention,
By providing the base for fixing the superconducting wire, it is possible to prevent deterioration of the wire at the connection portion.

According to an eighth aspect of the present invention, there is provided a superconducting coil device according to the seventh aspect, wherein the maximum height of the fixing stand is at least e times the wire diameter or the tape equivalent diameter.

According to the superconducting coil device according to the present invention,
When the height of the fixing base is at least e times the equivalent diameter of the superconducting wire, the influence of the magnetic field of the superconducting wire in the inner layer can be suppressed, and the AC loss generated by the magnetic field can be reduced.

According to the ninth aspect of the present invention, a groove having a width larger than the wire diameter or width of the superconducting wire is formed in the fixed base, and the superconducting wire is made to extend along the groove. To provide a superconducting coil device.

According to the superconducting coil device of the present invention,
By inserting a wire into the groove above the fixing base, the superconducting wire at the connection portion can be protected.

According to a tenth aspect of the present invention, in the superconducting coil device according to any one of the seventh to ninth aspects, the fixing base has a groove in a portion of the inner layer joined to the surface of the superconducting wire. provide.

According to the superconducting coil device according to the present invention,
By providing the groove below the fixing base, it is possible to prevent the cooling of the superconducting wire of the inner layer from being hindered.

According to the eleventh aspect of the present invention, the superconducting wire has a tape shape, and is wound in a state where two or more superconducting wires are stacked for each layer. Provided is a superconducting coil device.

According to the superconducting coil device according to the present invention,
By setting the number of superconducting wires to two or more, there is an advantage that a loss can be reduced even when the current capacity is increased.

According to a twelfth aspect of the present invention, a superconducting wire in which two or more m sheets are stacked is used, and the mth sheet from the winding side of the inner layer and the first sheet on the winding side of the outer layer are used. And the m-1 sheet from the winding side of the inner layer and the second sheet from the winding side of the outer layer are connected to each other, and then connected in the same order, thereby forming a tape-shaped superconductor. 12. A connection structure in which the total lengths of the lines are equal to each other.
And a superconducting coil device according to (1).

According to the superconducting coil device of the present invention,
By connecting each superconducting wire inside and outside, that is, nesting, it is possible to make the total length of the wires used uniform, and even if the current capacity is increased, it is possible to prevent drifting, from that viewpoint Can also be expected to have a low loss.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a superconducting coil device according to the present invention will be described below with reference to FIGS.

First Embodiment (FIGS. 1 to 3) FIG. 1 shows a basic configuration example. FIG. 1 (a)
Shows the configuration of the inner layer (n-1 layer),
(C) shows a configuration in which the inner layer is connected to the outer layer (n layer).

In this embodiment, as shown in FIG. 1A, first, an inner superconducting wire 1 is wound clockwise around a cylindrical winding frame 2 (right-handed winding), and one end of the superconducting winding 1 is wound. Reel 2
At a predetermined fixed position 3 and fixed by soldering. It is desirable that a fixing block made of metal, for example, copper, having the same curvature as that of the bobbin 2 is installed in the fixing position 3 in advance.

Next, the bonding position by the solder 4 is set on the surface near the fixed end of the superconducting wire 1 on the inner layer, and thereafter, as shown in FIGS. Line 7
Are overlapped and joined by solder 4.

Thereafter, a large-diameter cylindrical outer winding frame 6 having a notch 5 at an end portion is put on the outer peripheral side of the inner winding frame 2, and the outer superconducting wire 7 is inserted through the notch 5. A two-layer coil is manufactured by winding rightward on the winding frame 6. The radius of curvature R of the superconducting wire 7 is set so that the generated strain is 0.15% or less.

According to such a configuration, the superconducting wire 1 of n-1 layers and the superconducting wire 7 of n layers are directly
Is connected, the performance is not degraded due to strain, and the loss of the connection portion can be reduced as compared with the conventional one connected by copper electrodes.

FIG. 2 shows the soldering lengths of 1 cm, 5 cm,
The relationship between the solder length and the loss when the length is 10 cm is shown by experimental results. As shown in FIG.
According to the present embodiment, it is recognized that the loss is extremely small.

FIG. 3 shows a specific configuration in which the joining portions of the superconducting wires 1 and 7 are fixed by a fixing base.

In this example, the width is 3.9 mm and the thickness is 0.25
mm Bi2223 tape with superconducting wire
A non-inductive coil of 0V20A class is applied.

First, the superconducting wire 1 of the first layer is wound right around the winding frame 2, and the end of the superconducting wire 1 is fixed at a predetermined fixed position 3.
And fix it by soldering, and cut the superconducting wire. next,
As shown in FIGS. 3A, 3B and 3C, for example, non-magnetic, for example, GFRP (Glass Fiber Rei)
A fixed base 8 made of nforced Plastic (glass fiber reinforced plastic) is attached to the bobbin 2 with fasteners 1 such as bolts.
Fixed by 0. The fixing base 8 has, for example, a U-shaped cross section, and has grooves 9 and 11 on both sides. These grooves 9 and 11
Superconducting wires 1 and 7 have a size that can be inserted, and are formed along the winding direction. Then, 3 cm of solder is attached at a position 1 cm before the superconducting wire 1 and the superconducting wire 7 of the second layer is connected by 3 c
m, and with the superconducting wire 7 stretched,
It is configured by covering the second-layer reel 6.

Then, the superconducting wire 7 is inserted into the groove 9 of the fixing base 8 having a height of 1 cm and a radius of curvature of 10 cm, and the second-layer superconducting wire 7 is wound around the winding frame 6 by right-hand winding. To manufacture. The portion of the fixed base 8 that is in contact with the second-layer bobbin 6 has the same height, and the superconducting wire 7 is smoothly wound from the fixed base 8 to the bobbin 6. The fixed base 8 has a width of 3.9 m.
m, a height sufficiently higher than e times the equivalent diameter of the tape-shaped superconducting wire having a thickness of 0.25 mm.

According to the superconducting coil device of the present embodiment having the above configuration, the performance is not degraded due to the strain, and the loss of the connection portion is reduced by 8 times as compared with the conventional case where the connection is made by the copper electrode.
% To 0.12%.

Second Embodiment (FIG. 4) FIG. 4 is a specific configuration diagram for explaining a second embodiment of the present invention.

In this embodiment, the superconducting conductor has a width of 3.
A two-layer non-inductive coil was formed by using two Ag alloy Bi2223 superconducting tapes each having a thickness of 9 mm and a thickness of 0.24 mm. The first layer had a diameter of 20 cm and the second layer had a diameter of 22 cm. Things.

That is, the first superconducting wire 12 and the second superconducting wire 13 are wound on the GFRP grooved winding frame 2 as the first layer by right-hand winding, and first, the end of the first superconducting wire 12 is fixed. At the position 3, it is fixed to the copper bobbin 2 by soldering (4) and then cut. The second superconducting wire 13 is soldered (4 ') to the surface of the first superconducting wire 12 at a position 10 cm before the fixing position 3 of the first superconducting wire 12, fixed, and cut.

Next, the solder 4a is attached to the surface of the second superconducting wire 13 2 cm before the position of the solder 4 'with a length of 3 cm, and the second superconducting wire 14 of the second layer is soldered thereto. I do. Further, the second superconducting wire 15 of the second layer is soldered (4b) to the surface 2 cm before the fixing position 3 at the end of the first superconducting wire 12 of the first layer. , 15 under a tension of 4 MPa, is covered with a GFRP grooved reel 6 of the second layer. Needless to say, the first-layer superconducting coils 12, 13 are also wound with a tension of 4 MPa.

Then, the second winding frame 6 is wound right-handed to produce a coil. As a result, the total length of the tape as a coil is 50 m and 50.1 m, which can be almost matched.

According to the present embodiment, when a non-inductive element for a current limiting element of 6.6 kV 100 A class is manufactured for a current limiting element, it is possible to adopt a configuration in which the lengths of tapes used are equal, thereby reducing the drift. In addition, the loss can be reduced, and an element having an efficiency of 99% or more can be obtained.

Third Embodiment (FIG. 5) FIGS. 5 (a), 5 (b) and 5 (c) are specific structural diagrams for explaining a third embodiment of the present invention.

This embodiment relates to a three-layer non-inductive coil using one Ag alloy Bi2212 tape as a superconducting wire. The first layer has a diameter of 20 cm, and the second layer has a diameter of 22 cm.
cm, the third layer has a diameter of 24 cm.

In this embodiment, up to the second layer, the same procedure as in the first embodiment is used.

Next, the coil is turned upside down and attached to a winding machine (not shown), and solder is placed on the superconducting wire 7 3 cm before the portion soldered at the winding end position 16 of the second layer. 4 cm, 3 cm superconducting wire 17 of 4 cm
Soldering, and with this superconducting wire 17 stretched, 3
The reel 18 of the layer is covered. Then, the superconducting wire 17 is wound right-hand around the winding frame 18 of the third layer to manufacture a coil.

When a PCS was manufactured according to the present embodiment, high performance with a permanent current mode time of 12 hours was obtained.

[0056]

As described in detail in the above embodiment, according to the present invention, in a superconducting coil device for independently producing two or more layers, superconducting wires are directly connected to each other by soldering. As a result, an excellent effect that the loss can be reduced and the electric field concentration can be largely suppressed can be achieved.

[Brief description of the drawings]

FIGS. 1A, 1B, and 1C show a first embodiment of a superconducting coil device according to the present invention, and are explanatory views of a basic configuration. FIG.

FIG. 2 is a graph showing a relationship between a loss and a soldering length according to the embodiment.

FIGS. 3A and 3B are diagrams showing a specific configuration of the first embodiment.

FIG. 4 is a specific configuration diagram showing a second embodiment of the superconducting coil device according to the present invention.

FIGS. 5A, 5B, and 5C are specific configuration diagrams showing a third embodiment of a superconducting coil device according to the present invention.

6A and 6B are explanatory diagrams showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Superconducting wire 2 (n-1st layer) winding frame 3 Fixed position (of superconducting wire) 4 Solder 5 Notch 6 (nth layer) winding frame 7 (n-1st layer) superconducting wire 8 (nonmagnetic) ) Fixing stand 9 Groove (into which superconducting wire enters) 10 Fastener 12 First superconducting wire (of n-1 layer) 13 Second superconducting wire (of n-1 layer) 14 First (of n layer) Superconducting wire 15 (n-layer) second superconducting wire 16 Fixed position (at end of (n + 1) th layer) 17 Superconducting wire (nth layer) 18 (n + 1th layer) Reel 19 (copper) electrode 20 Connection Tool 21 Curvature of the part where superconducting wire runs

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshihisa Takahashi 4-1 Egasakicho, Tsurumi-ku, Yokohama-shi, Kanagawa Prefecture Inside the Electric Power Research Laboratory, Tokyo Electric Power Company (72) Inventor Rebun Sato, Emi, Tsurumi-ku, Yokohama-shi, Kanagawa 4-1, Kasaki-cho, Tokyo Electric Power Co., Inc. (72) Inventor Eriko Yoneda 2--4, Suehirocho, Tsurumi-ku, Yokohama-shi, Kanagawa Prefecture Inside Keihin Plant, Toshiba Corporation (72) Inventor Katsumasa Araoka Kawasaki, Kanagawa Prefecture 2-1, Ukishima-cho, Ichikawasaki-ku

Claims (12)

[Claims] 1. A superconducting coil device having two or more layers of coil portions each formed by winding a superconducting wire around a bobbin, wherein each of the coil portions is previously formed as an independent member for each layer, and the superconducting layer between each layer is provided. A superconducting coil device comprising a plurality of layers in which wires are electrically connected to each other directly at one or more locations. 2. The superconducting wire of the inner layer is mechanically fixed to the bobbin, and the superconducting wire of the outer layer is electrically connected to a position near the fixed end of the superconducting wire of the inner layer. The superconducting coil device according to claim 1, wherein: 3. The superconducting coil device according to claim 1, wherein the bobbin of the second or higher layer has a notch at a portion where the superconducting wire rises from the inner layer. 4. The superconducting wire electrically connected from one layer to a different layer has a curvature diameter set at an end portion such that a strain generated in the superconducting wire is 0.15% or less. The superconducting coil device according to claim 1. 5. The superconducting coil device according to claim 1, wherein the superconducting wires of each layer are joined by soldering, and the length of the soldering is set to 1 cm or more. 6. The superconducting coil device according to claim 1, wherein the number of layers of the coil portion is three or more. 7. The fixing device according to claim 1, further comprising a fixing base made of a non-magnetic material for fixing and holding the superconducting wire at a portion where the superconducting wire extends from the inner layer to the outer layer. The superconducting coil device according to any one of the above. 8. The superconducting coil device according to claim 7, wherein the maximum height of the fixing stand is at least e times the wire diameter or the tape equivalent diameter. 9. The superconducting coil device according to claim 7, wherein a groove having a width larger than the diameter or width of the superconducting wire is formed in the fixing base, and the superconducting wire is made to extend along the groove. 10. The fixing base has a groove in a portion of the inner layer joined to the surface of the superconducting wire.
10. The superconducting coil device according to any one of claims 9 to 9. 11. The superconducting coil device according to claim 1, wherein the superconducting wire has a tape shape and is wound in a state where two or more superconducting wires are stacked for each layer. 12. An m-th superconducting wire in which at least two m-layers are superimposed, connecting the m-th layer from the bobbin side of the inner layer and the first-layer bobbin side of the outer layer, By connecting the m-1st sheet from the winding side of the inner layer and the second sheet from the winding side of the outer layer, and connecting them in the same order, the total length of the tape-shaped superconducting wire becomes The superconducting coil device according to claim 11, wherein the connection structure is equal.