JP3228100B2 - Terminal structure of cryogenic cable - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal structure of a cryogenic cable such as a superconducting cable used for a power transmission cable or the like.

[0002]

2. Description of the Related Art FIG. 4 is a longitudinal sectional view of an example of a conventional cryogenic cable terminal structure. In the drawing, reference numeral 1 denotes an outer wall of a cryogenic bath in which a cryogenic bushing 5 at an end of a cryogenic cable 4 is housed and a refrigerant 2 such as a liquefied gas is sealed therein. Is welded or screwed to the outer wall of Reference numeral 3 denotes a vacuum vessel outer wall which is located outside the cryogenic vessel outer wall 1 and maintains a vacuum state between the cryogenic vessel outer wall 1 and an end thereof is air-tightly connected to a cryogenic cable 4. Reference numeral 7 denotes a terminal connection box in which an insulating oil 9 is filled in a porcelain tube 8, reference numeral 6 denotes a conductor drawing rod, which penetrates the terminal connection box 7 through the refrigerant 2 in the outer wall 1 of the cryogenic bath. It is connected to an outside line.

[0003]

Since the cryogenic cable has a very low operating temperature, the cable shrinks, and the terminal portion of the cryogenic cable is pulled in the line direction of the cable, that is, in the direction of arrow a in the figure. Works. In the conventional cable terminal described above, since no countermeasure is taken against this contraction force structurally, there is a possibility that the terminal portion may be damaged.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and provides a terminal structure of a cryogenic cable in which structural measures against heat shrinkage of the cable are taken. A cryogenic bushing at the end of the cable is housed, and a flange B provided on the outer wall of the cryogenic bath in which a refrigerant such as a liquefied gas is sealed is located outside the outer wall of the cryogenic bath and the outer wall of the cryogenic bath. A support member is provided between the vacuum chamber and the flange A provided at the end of the outer wall of the vacuum chamber in which a vacuum state is maintained,
That is, the flange A is fixed to a building fixed to the ground.

[0005]

FIG. 1 is a longitudinal sectional view of a specific example of a terminal structure of a cryogenic cable according to the present invention. In the drawings, the same reference numerals as those in FIG. 4 indicate the same parts. As shown in the drawing, the end of the outer wall 1 of the cryogenic bath in which the cryogenic bushing 5 at the end of the cryogenic cable 4 is housed and the refrigerant 2 such as liquefied gas is sealed inside is connected to the cryogenic bushing via a flange C. 5 is welded or screwed to the outer wall. The end of the outer wall 3 of the vacuum chamber, which is located outside the outer wall 1 of the cryogenic chamber and maintains a vacuum state with the outer wall 1 of the cryogenic chamber, is airtightly connected to the cryogenic cable 4 via a flange A12. Have been. Further, a flange B11 is provided on the outer periphery of the outer wall 1 of the cryogenic bath, and a support member 13 described later is provided between the flange B11 and the flange A12. The flange A12 is fixed to a building 14 fixed to the ground via a fixing member 15. The terminal connection box 7 is the same as the conventional one.

In the terminal portion of the cryogenic cable of the present invention having the above-described structure, when the cryogenic cable 4 is cooled to a cryogenic temperature, it undergoes thermal contraction, and is caused in the cable line direction (the direction of arrow a in the drawing). Power works. This power is a cryogenic bushing 5
To the flange C10 which is welded or screwed,
It is transmitted to the flange B11 via the outer wall 1 of the cryogenic bath. A support member 13 is provided between the flange B11 and the flange A12, and the heat shrinkage is transmitted to the flange A12 via the support member 13. Since the flange A12 is fixed to the building 14 fixed to the ground via the fixing member 15, the cable terminal is not pulled in the cable line direction, and the terminal is not damaged. .

An example of the shape of the support member 13 is shown in FIG.
A cylindrical shape as shown in (a) is conceivable. The thickness and length of the cylinder are designed to sufficiently withstand the heat absorbing power of the cable portion in consideration of the strength of the constituent material. Since the support member 13 is installed in a vacuum chamber, if there is no problem in strength, slits 13a and holes 13b are provided on the side wall to reduce the vacuum conductance as shown in FIGS. Preferably it is better.

As another shape of the support member 13, FIG.
As shown in (a) and (b), a plurality of wires 131 or ropes 133 are annularly arranged between the flange B11 and the flange A12, and are attached to the flange B11 and the flange A12 by the fixing member 132. Is also good.

[0009] Heat is conducted from room temperature to extremely low temperature through these support members. These conduction heats increase the temperature of the refrigerant and increase the consumption of the refrigerant. Therefore, it is preferable that these support members are made of a material having a small thermal conductivity and a mechanical strength at an extremely low temperature, and examples of the material include stainless steel, glass fiber reinforced plastic, and carbon fiber reinforced plastic. .

[0010]

As described above, according to the terminal structure of the cryogenic cable of the present invention, the cable terminal portion is prevented from being damaged by the heat shrinkage generated in the cable used at the cryogenic temperature, and the reliability is improved. The terminal part of the cryogenic cable having a high temperature can be provided.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a specific example of a terminal structure of a cryogenic cable according to the present invention.

FIGS. 2A to 2C are perspective views showing examples of the shape of a support member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cryogenic tank outer wall 9 Insulating oil 2 Refrigerant 10 Flange C 3 Vacuum tank outer wall 11 Flange B 4 Cryogenic cable 12 Flange A 5 Cryogenic bushing 13 Supporting member 6 Conductor lead-out rod 14 Building 7 Terminal connection box 15 Fixing member 8 Insulator pipe

FIGS. 3A and 3B are explanatory views of another example of the shape of the support member. FIGS.

FIG. 4 is a longitudinal sectional view of an example of a conventional cryogenic cable terminal structure.

Claims (2)

(57) [Claims] A cryogenic bushing at an end of a cryogenic cable is housed therein, and a flange B is provided on an outer wall of the cryogenic bath in which a refrigerant such as a liquefied gas is sealed, and is located outside the outer wall of the cryogenic bath. Heat collection of the cable between the outer wall of the cryogenic chamber and a flange A provided at the end of the outer wall of the vacuum chamber in which a vacuum state is maintained.
Provided a support member for transmitting the reduced force, to restrict the movement of for the building which is fixed to the ground the flange A into line direction
Terminal structure of the cryogenic cable, characterized in that fixed to so that. 2. The cryogenic cable terminal structure according to claim 1, wherein the support member has a cylindrical shape.