JPS61180512A - Construction of directly cooled type power cable line - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for constructing a directly cooled power cable line.

Conventionally, as shown in Fig. 1, this type of line was constructed by placing the cable 1 in a direct cooling pipe 3, filling the pipe 3 with a cooling medium (water), and directly cooling the cable. In order to increase the cooling effect in this method, it is common to increase the amount of water, that is, increase the diameter of the pipe.

However, if you try to absorb the thermal expansion and contraction of the cable 1 by making the pipe diameter thicker (by making the pipe diameter larger), the cable 1 will snake inside the direct cooling pipe 3, and the bending will become smaller locally. Problems such as increased distortion are expected.

In view of the above-mentioned circumstances, the present invention improves cooling efficiency, lengthens the refrigerant supply/discharge section, and also regulates the snake width to prevent local bending diameters and increases in distortion in the cable. , aims to provide a method for configuring a directly cooled power cable line.

That is, the method of the present invention includes an inner tube that directly covers the cable and has a plurality of radial through holes formed in the longitudinal and circumferential directions, and an outer tube that covers the inner tube. and is configured to flow refrigerant between the inner tube and the outer tube and between the inner tube and the cable so that the refrigerant inside and outside can freely exchange and circulate through the through hole of the inner tube. It is.

An embodiment of the method of the present invention will be described below with reference to FIGS. 2 and 3.

The conduit for accommodating the cable 1 is composed of a large-diameter outer tube 4 and an inner tube 3 housed in the outer tube 4, and the cable 1 is drawn into the inner tube 5 and housed therein.

The outer pipe 4 forms a pipe outer wall that is closed to the outside, that is, seals off the refrigerant, while the inner pipe 5 has a diameter sufficiently smaller than that of the outer pipe 4 and slightly larger than that of the cable 1, and has a diameter slightly larger than that of the cable 1. A plurality of 66 penetrating holes are bored in the longitudinal direction and the circumferential direction.

The refrigerant 2 is filled into the outer pipe 4, and therefore the outer pipe 4 and the inner pipe 5
and the cable l in the inner tube 5.

The through hole 6 of the inner tube 5 maintains an open state to the inner space accommodating the cable 1 and the external space surrounded by the outer tube 4 so as not to impede the penetration state, and therefore, the refrigerant 2
can freely flow into the inner tube 5 and the outer tube 4 through the through hole 6.

In this way, the present invention differs from simply increasing the diameter of the pipe to increase the amount of refrigerant (water) in order to increase cooling efficiency. The cable is constructed with holes penetrating in the direction so that the refrigerant in the inner tube and the refrigerant in the outer tube can freely flow.
The refrigerant heated in the inner tube 5 by the heat generated by the energization flows into the outer tube 4 outside the inner tube 5 through the through hole 6, and the refrigerant in the outer tube 4 flows into the inner tube 5 through the through hole.
In this way, the refrigerant inside and outside the inner tube 4 can be exchanged freely,
That is, since the refrigerant is substantially stirred within the cooling pipe, it is possible to further improve the cooling efficiency in addition to increasing the amount of water, contributing to a further increase in current capacity.

Furthermore, since the refrigerant in the inner tube and the refrigerant in the outer tube communicate through the through hole in the inner tube, their refrigerant pressures are balanced, and there is no concern that excessive external pressure will be applied to the inner tube. That is, although tubes are generally strong against internal pressure, they tend to buckle against external pressure, but there is no risk of buckling.

Furthermore, since the refrigerant is kept in an agitated state within the double internal and external conduits to cool the cable, the refrigerant supply and discharge section can be lengthened.

When the bending diameter and distortion are about to occur due to expansion and contraction of the cable due to thermal expansion and contraction, the inner tube 5 that directly covers the cable can effectively act on the cable bending diameter and cable distortion.

In the above example, the case where the refrigerant is water is described, but in the method of cooling the fingers and hands of a POF (pipe type oil-filled) cable, the structure is completely unchanged by simply replacing water and oil, and the external It is also possible to further provide an outer outer tube on the outside of the tube and to circulate water between the outer tube and the outer outer tube.

As explained above, according to the method for configuring a directly cooled power cable line of the present invention, it is possible to improve the cooling efficiency and lengthen the refrigerant supply/discharge section, and also to restrict the snake width so that the cable can be locally cooled. This has the effect of preventing the bending diameter and distortion from increasing, and the practical benefits are great.

[Brief explanation of drawings]

Figure 1 is a sectional view showing an overview of a conventional direct cooling type power cable line, and Figures 2 and 3 are cross sections showing an example of a line structure according to the method of configuring a direct cooling type power cable line of the present invention. It is a figure and a side explanatory view. Cable 2: Refrigerant 4: Outer pipe 5: Inner pipe 6: Through hole

Claims (1)

[Claims] 1. In a power cable line where the cable is installed in a conduit and a refrigerant is flowed through the conduit to directly cool the cable,
an inner pipe that directly covers the cable and has a plurality of radial through holes formed in the longitudinal direction and the circumferential direction;
It consists of an outer tube that covers this inner tube, and refrigerant is flowed between the inner tube and the outer tube and between the inner tube and the cable, and the refrigerant inside and outside can be exchanged freely through the through hole of the inner tube. A method of configuring a directly cooled power cable line, the method comprising configuring it so as to allow it to flow.