JP2004311172A - Transposed segment and superconductive application device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transposed segment capable of restraining edge wise distortion generated on a strand twisted so as to transpose at a transposition crossing part, and to provide a superconductive application device. <P>SOLUTION: On the transposed segment 10 formed by twisting and transposing a plurality of tape-shaped strands 20, a first protection tape 45 bundling a non-transposition crossing part 52 of the transposed segment 10 and a second protection tape 40 bundling a transposition crossing part 51 are arranged, and a relations of 0.25≤L2, and L1≤0.40 are fulfilled, wherein, L1 is the length of the transposition crossing part 51, and L2 is the length between the end of the first protection tape 45 in width direction and the center of the second protection tape 40 in width direction. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a dislocation segment formed by twisting a plurality of strands with dislocations and a superconducting applied device. More specifically, when manufacturing dislocation segments using a wire made of a mechanically brittle material, a dislocation segment and a superconducting application device capable of suppressing bending strain applied to a twisted wire when it is small. About.
[0002]
[Prior art]
As a method of suppressing a particular drift caused by applying an alternating current to a superconducting cable, a dislocation twisted wire structure called a dislocation superconducting tape unit (hereinafter, dislocation) formed by twisting a plurality of strands of a tape-shaped superconductor into dislocations. A segment is abbreviated (for example, see Patent Document 1).
[0003]
[Patent Document 1]
JP-A-11-203958
FIG. 10 shows an example of a conventional dislocation segment. FIG. 10 (a) is a perspective view, and FIG. 10 (b) is a cross-sectional view taken along the line YY '. As shown in FIG. 10, for example, a dislocation segment 80 in which a plurality of tape-shaped strands 810 are displaced and twisted has a dislocation portion where a specific strand 810 crosses over another adjacent strand 810. Hereinafter, referred to as a dislocation crossover portion) 820. For example, when the strand 810 is made of a highly flexible metal material, for example, if the width of the strand 810 is set to, for example, about 2 mm, the length of the dislocation transition portion 820 can be set to about 100 mm. .
[0005]
Further, in the dislocation segment 80 having the above-described configuration, a predetermined portion between adjacent dislocation transition portions 820 and 820 (non-dislocation transition portion 830) is bound by a shape-retaining tape 840 in order to maintain the structure. The shape-retaining tape 840 has one surface coated with an adhesive, and is adhered and fixed to the strand 810 via the adhesive.
[0006]
As is apparent from FIG. 10, in the dislocation segment 80 having the above configuration, the strands 810 are bound by the shape-retaining tape 840 only at the non-dislocation transition portion 830. Therefore, for example, the tape-shaped element wire 810 in the twisted state at the dislocation crossover portion 820 receives a large distortion (edgewise distortion) in the width direction, particularly in the case of a wide tape-shaped wire. become.
[0007]
In the case of a dislocation segment having such a structure that a large edgewise strain is inherent therein, if the strand is made of a material having a brittle property such as an oxide superconducting material, the edgewise strain is affected by the wire property. And may cause fatal deterioration, which is a factor that greatly impairs the electric conduction characteristics.
[0008]
Therefore, since there is a risk of electric loss or even breakage, dislocations having a structure with small edgewise distortion are also required from the viewpoint of maintaining stable electric conduction characteristics and establishing high long-term reliability. Segment development was expected.
[0009]
[Problems to be solved by the invention]
The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a dislocation segment and a superconducting applied device capable of reducing edgewise distortion generated in a strand in a dislocation twisted state at a dislocation transition portion. Aim.
[0010]
[Means for Solving the Problems]
The dislocation segment according to the present invention, a plurality of tape-shaped strands, in a dislocation segment formed by twisting dislocations, the non-dislocation transition portion constituting the dislocation segment, the first shape-retaining tape to be bound, A second shape preserving tape that binds the dislocation crossover portion is disposed at the dislocation crossover portion, and the length of the dislocation crossover portion is measured from L1, the width direction end of the first shape preservation tape, and When the length up to the center in the width direction of the second shape-retaining tape is L2, 0.25 ≦ L2 / L1 ≦ 0.40.
[0011]
That is, since the dislocation segment employs a configuration in which a plurality of tape-shaped strands are twisted with dislocations, the dislocation segment is integrated as a whole and has the ability to maintain its shape even when an external force is applied. Can be provided.
[0012]
Further, a non-dislocation crossover part constituting the dislocation segment according to the present invention is provided with a first shape retaining tape for binding the same. The non-dislocation transition portion has a structure in which a plurality of strands are overlapped and two stacked layers are arranged in parallel in the width direction. By bundling the non-dislocation transition portion having such a structure with the first shape-retaining tape, the dislocation segments are fixed at predetermined intervals at which the non-dislocation transition portion is provided. The form is preserved.
[0013]
Further, a second shape-retaining tape for binding the dislocation crossover portion constituting the dislocation segment according to the present invention is provided. The dislocation crossover portion is composed of a portion in which a plurality of strands are overlapped and a stacked body is arranged in two rows in the width direction, and an upper surface or a lower surface of the stacked body located on the left and right sides of the portion. Has a structure in which dislocation twisting is performed from one laminate side to the other laminate side. By bundling the dislocation crossover portion with such a structure with the second shape retaining tape, the dislocation segments are fixed at predetermined intervals at which the dislocation crossover portion is provided, and as a result, the form of the dislocation segment is changed. Will be kept.
[0014]
In particular, the second shape preserving tape according to the present invention is characterized in that the length of the dislocation crossover part is L1, and the second shape preserving tape is measured from the width direction end of the first shape preserving tape. When the length up to the center in the width direction is L2, the relationship of 0.25 ≦ L2 / L1 ≦ 0.40 is established.
[0015]
By arranging the second shape retaining tape so that the value obtained by dividing L2 by L1 is equal to or greater than 0.25 and equal to or less than 0.40, the element wire of the translocation transition portion is moved in the width direction, and the second shape retaining tape is moved. By fixing with the shape retaining tape, it is possible to greatly reduce the distortion (edgewise distortion) that the tape-shaped element wire in the twisted state at the dislocation transition portion receives in the width direction. .
[0016]
Further, a third shape-retaining tape may be provided in addition to the second shape-retaining tape in order to bind the above-described dislocation crossover portion. By providing such a third shape-retaining tape, it is possible to further suppress the edgewise distortion generated at the dislocation transition portion. The number of the third shape retaining tapes is not particularly limited.
[0017]
In the present invention, a wire provided with a superconducting layer on a metal substrate can be used as the element wire. In the dislocation segment according to the present invention, the non-dislocation transition portion is provided with a first shape retaining tape for binding the same, and the dislocation transition portion is provided with at least a second shape retaining tape for binding the same, There is no need to dare to select a material having a suitable flexibility for the substrate as in the prior art.
[0018]
Therefore, it is difficult to twist the dislocations, but it is possible to use a metal substrate having high strength and high rigidity. In particular, it is more preferable to use, for example, stainless steel or a Hastelloy alloy as the metal substrate because the tensile strength and rigidity can be remarkably enhanced.
[0019]
Further, as the superconducting layer according to the present invention, a layer composed of an oxide superconductor can be used. In the dislocation segment according to the present invention, since the above-described metal substrate can be used, it is easy to form a high-performance oxide superconductor layer on the surface of the metal substrate by using a thin film forming technique such as vapor deposition. That's why.
[0020]
A superconducting applied device according to the present invention is configured using the above-described dislocation segment of the present invention. Examples of the superconducting applied device include, for example, a superconducting cable, a superconducting transformer, a superconducting magnet, a superconducting current limiter, and the like.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a dislocation segment according to the present invention will be described with reference to the drawings of FIGS.
[0022]
<Dislocation segment>
FIG. 1 is a perspective view showing one embodiment of a dislocation segment according to the present invention. As shown in FIG. 1, the dislocation segment 10 of the present embodiment is a long strip having a plurality of tape-shaped strands 20 (six in the drawing) and twisted with dislocations.
[0023]
When a superconductor is used for the tape-shaped element wire 20, an intermediate layer such as YSZ, a superconductor such as YBCO is formed on a metal base such as Hastelloy, or a Bi-based multifilament filament / silver sheath wire. Is rolled to form a tape, or a metal superconductor such as Nb ₃ Sn or Nb ₃ Al is processed into a tape.
[0024]
A non-dislocation transition portion 52 constituting the dislocation segment 10 is provided with a first shape retaining tape 45 for binding the same, and a dislocation transition portion 51 is provided with a second shape retaining tape 40 for binding the same. ing.
[0025]
(1) Non-dislocation transition section 52
As shown in FIG. 1, in the binding portion 61 of the non-dislocation transition portion 52, the dislocation segment 10 is a single first winding wound around at least one round around all the superconducting tapes 20 constituting the non-dislocation transition portion 52. The shape-retaining tape 45 and the superconducting tape 20 are bound together with one end of the shape-retaining tape 45, and the other end on the winding end side is adhered and fixed to another portion of the shape-retaining tape 45 via an adhesive. Is provided so as not to be attached. At this time, it is preferable that the non-dislocation transition portion 52 be bound by the first shape-preserving tape 45 until the start of the dislocation transition portion 51.
[0026]
(2) Dislocation transition section 51
2A and 2B are cross-sectional views taken along the line AA ′ in the dislocation segment in FIG. 1, wherein FIG. 2A is a state before a second shape-retaining tape 40 is provided, and FIG. 2B is a second shape-retaining tape. The state after providing 40 is shown. Hereinafter, the binding unit 60 of the dislocation transition unit 51 will be described with reference to FIG.
[0027]
As shown in FIG. 2A, before the second shape retaining tape 40 is provided, the binding portion 60 of the dislocation transition portion 51 does not have any external fastening to all the wires 20 and is free. Was in a state.
[0028]
Assuming that the width of the wire 20 is W, for example, in the case of FIG. 2A, the distance between the center of the wire 20D in the width direction and the center of the twisted wire 20A in the width direction is The relationship was 5 / 32W.
[0029]
FIG. 2B is a cross-sectional view showing a case where the second shape retaining tape 40 is provided on the translocation transition portion 51 in the state shown in FIG. 2A. As shown in FIG. 2B, by providing the second shape-retaining tape 40, for example, the center in the width direction of the strand 20D and the center in the width direction of the strand 20A in a twisted state are provided. Can be reduced from 5 / 32W to 3 / 22W.
[0030]
Here, W is the width of each strand, and W 'is the width of the strand wrapped with the second shape-retaining tape. That is, W 'is obtained by adding twice the thickness of the second shape retaining tape to the width W of the strand. However, since the thickness of the second shape-retaining tape is sufficiently smaller than the width W of the strand, W ≒ W ′ may be used.
[0031]
As shown in FIG. 2B, by using the second shape retaining tape 40, by controlling the position of the strand 20A in the twisted state, the strand 20A is received in its width direction. Distortion (edgewise distortion) can be reduced. This operation / effect works more effectively as the width of the strand is wider. For example, when the width is about 2 mm, the edgewise distortion does not appear, but when the width is about 10 mm, this action significantly reduces the edgewise distortion of the twisted wire 20 </ b> A. Becomes possible.
[0032]
In particular, the length of the dislocation crossover portion 51 is L1, the widthwise end of the first shape preserving tape 45, that is, from the edge where the dislocation crossover portion 51 starts from the non-dislocation crossover portion 52. By providing the second shape-retaining tape 40 such that the relationship of 0.25 ≦ L2 / L1 ≦ 0.40 holds when the length of the tape 40 to the center in the width direction is L2, The edgewise distortion that the line 20A receives in the width direction can be significantly reduced.
[0033]
FIG. 3 is a graph showing the relationship between L2 / L1 and the maximum value λe (max) of the edgewise distortion that the wire receives in the width direction.
Here, L2 / L1 on the horizontal axis is the length L2 measured from the width direction end of the first shape-retaining tape 45 to the center in the width direction of the second shape-retaining tape 40, and is expressed as transposition. This is a value obtained by dividing by the length L1 of the transition portion 51. Further, λe (max) is the maximum value of the edgewise distortion when the transition strand is moved to minimize the maximum value and fixed with the shape-retaining tape.
[0034]
Λe (max) on the vertical axis indicates the edgewise distortion of the wire 20A when the second shape-retaining tape 40 is provided at a predetermined L2 / L1, and the second shape-retaining tape 40 Is a value obtained by dividing by the edgewise distortion that the element wire 20A receives when no wire is provided.
[0035]
As is clear from FIG. 3, the maximum value λe (max) of the edgewise distortion decreases sharply when L2 / L1 is between 0 and 0.25, and decreases when the value of L2 / L1 exceeds 0.25. It turned out that it calms down at the value of about 0.70.
[0036]
On the other hand, from FIG. 5, when it becomes 0.40 to 0.50, the force by which the second shape retaining tape restrains the strand increases, and the distance required for twisting the strand 20A by dislocation, ie, the dislocation transition part Is not good because the distance of is too long. Therefore, as a position where the second shape retaining tape is provided, L2 / L1 is preferably in a range of 0.25 or more and 0.40 or less. When the transition strand is moved to minimize the maximum distortion, that is, when L2 / L1 is 0.25 to 0.40, the maximum distortion can be reduced by 27% to 32%, and edgewise Distortion can be greatly reduced.
[0037]
FIG. 4 is a graph showing the relationship between L2 / L1 and the dislocation transfer ratio S, which is standardized when the second shape retaining tape is not provided.
Here, L2 / L1 on the horizontal axis has the same definition as in FIG.
[0038]
The transposition transition ratio S on the vertical axis is the amount of displacement of the strand 20A in the width direction when the second shape-retaining tape 40 is provided at a predetermined location L2 / L1, by the second protection. When the shaping tape 40 is not provided, this is a value obtained by dividing by the amount of displacement of the strand 20A in the width direction thereof.
[0039]
As shown in FIG. 4, the dislocation transition ratio S slightly increases until L2 / L1 becomes about 0.10, while it rapidly increases when L2 / L1 exceeds 0.10. The maximum value is obtained when L2 / L1 is around 0.35 to 0.375. Next, it was confirmed that when L2 / L1 exceeded 0.40, it rapidly decreased.
[0040]
From this result, if L2 / L1 is in the range of 0.25 or more and 0.40 or less, it becomes possible to stably maintain the translocation ratio S at 0.5 or more. In other words, if L2 / L1 is 0.25 to 0.40, a large amount of movement in the width direction for reducing edgewise distortion can be obtained, so that the error in the amount of movement when the tape is fixed is small, and stable. You can unite. Note that the inclination angle when L2 / L1 exceeds 0.40 is steeper than the inclination angle indicated between 0.25 and 0.35. It is difficult to always make the dislocation transition ratio S.
[0041]
FIG. 5 is a graph showing the relationship between L2 / L1 and the force F applied to the second shape-retaining tape, which is standardized when no second shape-retaining tape is provided.
Here, L2 / L1 on the horizontal axis has the same definition as in FIG.
[0042]
The force F applied to the second shape-retaining tape on the vertical axis is the shape-retaining tape 40 that binds the strands 20A when the second shape-retaining tape 40 is provided at a predetermined location of L2 / L1. Is divided by the repulsive force of the strand 20A when the second shape retaining tape 40 is not provided.
[0043]
From FIG. 5, the force F applied to the second shape-retaining tape hardly increases until L2 / L1 is about 0.10, and starts to slightly increase when L2 / L1 exceeds 0.10. Then, it was confirmed that when L2 / L1 was around 0.25, the increasing tendency of F became stronger, and especially when F exceeded 0.40, F became larger than 3, showing a sharper rising curve.
[0044]
When F exceeds 3, it has also been found that it is extremely difficult to stably hold the state for a long period of time after binding the wires 20A with the second shape retaining tape 40. Therefore, in order to suppress the force F applied to the second shape retaining tape to 3 or less, it is clear from FIG. 5 that L2 / L1 is desirably 0.40 or less.
[0045]
As described above, by arranging the second shape-retaining tape 40 so that the numerical value of L2 / L1 is not less than 0.25 and not more than 0.40, the maximum value of edgewise distortion λe (max), the translocation ratio S and the force F applied to the second shape-retaining tape can all be kept at a low level, so that the inherent edgewise distortion is small and the dislocation twist structure is not easily collapsed even when the coil is wound. A segment is obtained.
[0046]
That is, if the dislocation segment is formed by disposing the second shape-retaining tape 40 such that the numerical value of L2 / L1 becomes 0.25 or more and 0.40 or less, the wire constituting the dislocation segment may be oxidized, for example. Even when the material is made of a material having a brittle property, such as a superconducting material, the edgewise distortion is suppressed, so that the fatal deterioration of the wire characteristics is less likely to occur. Characteristics are secured.
[0047]
Therefore, according to the present invention, the occurrence of electric loss is suppressed, and thus the risk of breakage is reduced, stable electric conduction characteristics can be maintained, and it is possible to provide a dislocation segment with high long-term reliability. Become.
[0048]
A superconducting applied device according to the present invention is configured using the above-described dislocation segment of the present invention. Examples of the superconducting applied device include, for example, a superconducting cable, a superconducting transformer, a superconducting magnet, a superconducting current limiter, and the like.
[0049]
<Superconducting applied equipment>
Next, an embodiment of a superconducting application device using the dislocation segment according to the present invention will be described.
[0050]
[Superconducting cable]
FIG. 6 is a perspective view showing one embodiment of the superconducting cable.
The superconducting cable 470 of this embodiment has a structure in which drift is suppressed when an alternating current is applied, and the dislocation segment 10 is spirally wound around a pipe-like former (tube body) 477 to form a plurality. Are superposed, and an interlayer insulating layer 485 made of an insulating tape or the like is formed between the superconducting layers 484 and 484. Outside the superconducting cable 470, a semiconductor layer, an insulating layer, a protective layer, a heat insulating layer, an anticorrosion layer, and the like (not shown) are formed and used as necessary.
[0051]
The former 177 is made of stainless steel or the like, and its surface is subjected to an insulation treatment to suppress the current flow between the former 177 and the dislocation segment 10. The internal cavity is used as a flow path for a cooling medium such as liquid nitrogen, so that the plurality of wires 20 constituting the dislocation segment 10 are cooled.
[0052]
[Superconducting magnet]
FIG. 7 is a perspective view showing one embodiment of the superconducting magnet.
The superconducting magnet 590 of the present embodiment is obtained by winding the dislocation segment 10 around a winding frame 593 including a winding drum 591 and a pair of flange plates 592. An end portion 595a of the dislocation segment 10 is drawn out of the flange plate 592 through a notch-shaped through hole 592a formed in the peripheral portion of the flange plate 592, and the dislocation segment 10 that passes through the through hole 592a. The front portion 595b of the drawer portion is covered with a reinforcing plate 597 fixed to the outer peripheral edge of the flange plate 592.
[0053]
[Superconducting transformer]
FIG. 8 is a perspective view showing one embodiment of a superconducting transformer. FIG. 9 is a cross-sectional view taken along the line BB ′ of FIG.
The superconducting transformer 600 according to the present embodiment includes a bobbin 602 having a cylindrical winding drum 602a, and the above-described dislocation segment 10 wound in multiple layers from one axial end to the other axial end of the winding drum 602a of the bobbin 602. And a spacer 605 for separating each layer of the stacked dislocation segments 10 from each other.
[0054]
The bobbin 602 includes a winding drum 602a and flanges 602b and 602c provided at both ends thereof. The dislocation segments 10 are wound around the bobbin 602 in multiple layers around the outer circumference of the winding drum 602a.
[0055]
The spacer 605 is provided to separate the layers of the stacked dislocation segments 10 from each other and to allow the dislocation segments 10 to be efficiently cooled by the coolant, and the longitudinal direction thereof is along the bobbin axis direction. A plurality of bobbins 602 are provided at intervals in the circumferential direction.
[0056]
The spacing between the layers of the dislocation segment 10 and the spacing between the dislocation segment 10 and the flanges 602b and 602c are a cooling channel 604 serving as a coolant flow path. When the superconducting transformer 600 is used, the superconducting transformer 600 can be cooled by immersing it in a coolant such as liquid helium in order to maintain the superconducting state of the dislocation segments 10.
[0057]
As described above, in the superconducting application device described by taking the superconducting cable 470, the superconducting magnet 590, and the superconducting transformer 600 as examples, the second shape-preserving tape serving to bind the wires at the dislocation transition portion has a predetermined relationship, namely, 0. .25 ≦ L2 / L1 ≦ 0.40, which is configured using the dislocation segments 10 according to the present invention, which are arranged so as to satisfy the relationship.
[0058]
As described above, the dislocation segment 10 according to the present invention adopts this relationship, so that the twisted tape-shaped wire in the dislocation transition portion receives in the width direction the distortion (edgewise distortion). Could be greatly reduced.
[0059]
Therefore, since the dislocation segment 10 having such a low edgewise distortion is used, the superconducting application device according to the present invention has excellent superconducting characteristics, that is, AC loss when AC current is applied is reduced. Thus, the drift is suppressed and good characteristics are obtained.
[0060]
【The invention's effect】
As described above, in the dislocation segment according to the present invention, the position where the first shape retaining tape that binds the strands at the non-dislocation transition part and the second shape retaining tape that binds the strands at the dislocation transition part are provided. The relative relationship with the position where the tape is provided was set so as to satisfy the following expression: 0.25 ≦ L2 / L1 ≦ 0.40. By satisfying such a relation, it is possible to suppress the distortion in the width direction of the tape-shaped element wire in the twisted state at the dislocation transition portion to an extremely small value.
[0061]
Therefore, the present invention contributes to providing a dislocation segment that is less likely to cause electric loss or breakage and can maintain stable electric conduction characteristics.
[0062]
In addition, the dislocation segment having the above-described configuration contributes to providing various superconducting applied devices having excellent superconducting characteristics, that is, reduced AC loss when AC current is applied, suppressed drift, and having excellent characteristics.
[Brief description of the drawings]
FIG. 1 is a perspective view showing one embodiment of a dislocation segment according to the present invention.
FIG. 2 is a cross-sectional view taken along the line AA ′ in the dislocation segment of FIG. 1, showing a state (a) before a second shape retaining tape 40 is provided and a state (b) after the second shape retaining tape 40 is provided.
FIG. 3 is a graph showing a relationship between L2 / L1 and a maximum value λe (max) of edgewise distortion that a wire receives in a width direction thereof.
FIG. 4 is a graph showing a relationship between L2 / L1 and a dislocation transition ratio S.
FIG. 5 is a graph showing a relationship between L2 / L1 and a force F applied to a second shape-retaining tape.
FIG. 6 is a perspective view showing one embodiment of a superconducting cable according to the present invention.
FIG. 7 is a perspective view showing one embodiment of a superconducting magnet according to the present invention.
FIG. 8 is a perspective view showing one embodiment of a superconducting transformer according to the present invention.
FIG. 9 is a cross-sectional view of the superconducting transformer shown in FIG.
FIG. 10 is a schematic diagram illustrating an embodiment of a conventional dislocation segment.
[Explanation of symbols]
REFERENCE SIGNS LIST 10 dislocation segment, 20 strands, 40 second shape preservation tape, 45 first shape preservation tape, 51 dislocation transition part, 52 non-dislocation transition part, 60, 61 binding part, 80 transposition segment, 470 superconducting cable (Superconducting applied equipment), 590 Superconducting magnet (Superconducting applied equipment), 600 Superconducting transformer (Superconducting applied equipment), 810 strands, 840 Tape for shape preservation, 820 Translocation transition part, 830 Non-dislocation transition part.

Claims (5)

In a dislocation segment formed by twisting a plurality of tape-shaped wires,
The first shape-retaining tape for binding the non-dislocation transition portion constituting the dislocation segment, the second shape-retention tape for binding the dislocation transition portion is disposed,
When the length of the dislocation crossover portion is L1, and the length from the width direction end of the first shape-retaining tape to the center in the width direction of the second shape-retaining tape is L2, A dislocation segment, wherein 0.25 ≦ L2 / L1 ≦ 0.40. The dislocation segment according to claim 1, further comprising a third shape-retaining tape for binding the dislocation crossover portion, in addition to the second shape-retaining tape. The dislocation segment according to claim 1, wherein the wire has a superconducting layer on a metal substrate. The dislocation segment according to claim 3, wherein the superconducting layer is made of an oxide superconductor. A superconducting application device using the dislocation segment according to any one of claims 1 to 4.

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