JP2001078344A - Air cooling system for power cable in culvert - Google Patents

Abstract

PROBLEM TO BE SOLVED: To air cool power cables efficiently and economically while saving the space by storing compressed air in a compression air storage tank and releasing compressed air into a culvert as required. SOLUTION: An air compressor 12 is operated with power at night to produce compressed air which is stored in a compression air storage tank 11 and released into a culvert 13 during a time band, afternoon of a day, when power demand has a peak. Since temperature drops through expansion of compressed air, power cables can be cooled efficiently. Furthermore, since compressed air produced at night is stored in a compression air storage tank and discharged into a culvert in the afternoon of a day, energy and space can be saved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system (method or apparatus) for cooling a power cable by blowing air into a sinus where a power cable is laid.

[0002]

2. Description of the Related Art The following method is used to cool a power cable by blowing air to a cave where a power cable is laid.

(1) As shown in FIG. 2, a method of taking in outside air into a sinus passage 2 by a fan 1 installed on the ground to cool a power cable (not shown).

(2) As shown in FIG. 3, the outside air cooled by the cooling tower 3 and the heat exchanger 4 is blown into the cave 2 by the blower fan 1 to cool the power cable (not shown). how to.

(3) As shown in FIG.
Compressed air is blown out from the perforated air supply pipe 3 attached to
A method of cooling the power cable by spraying it on the power cable 2 in the tunnel 1. Reference numeral 4 denotes a fumarole formed in the air supply pipe 3. (Japanese Patent Publication No. 46-24831)

[0006]

SUMMARY OF THE INVENTION The above-mentioned power cable air cooling system in a canal has the following points to be improved. That is, it is necessary to cool the power cables laid in the tunnel mainly during peak hours of power demand; during the afternoon during the day. Other than that time, since the load condition of the power cable is relatively low, the calorific value is small, and cooling is rarely required.

In the method of (1) cooling the power cable by taking in the outside air into the sinus by the blower fan, the outside air is warmed up in the afternoon by the ventilation fan at the time when the power cable is desired to be cooled (afternoon in the daytime). Since the heat is taken into the cave as it is, the ability to cool the heating power cable is very small, and the cooling efficiency is very low.

In the method (2) for cooling the power cable by blowing the outside air cooled by the cooling tower and the heat exchanger into the passage, the cooled air is blown into the passage, so that the power cable is cooled. The ability to cool is very large. However, there were the following points to be improved. -In the afternoon hours during the day when power demand is at its peak, enormous power is required to cool the outside air taken into the tunnel.・ The cooling system as a whole, such as a cooling tower for cooling the outside air, a blower fan, and control equipment, is large-scale, and the installation site must be large, making it difficult to secure installation space in urban areas. Even if it can be secured, the installation cost is very high.

In the method (3), in which compressed air is blown out from an air supply pipe provided alongside the power cable, and the compressed air is blown against the power cable to cool the power cable, the following improvements should be made in the same manner as in the above (2). There was a point.・ To produce compressed air during the afternoon hours during the day when power demand is at its peak,
It requires a huge amount of power to run the compressor.・ Because it is a large-scale system for producing compressed air and requires a large installation site, it is difficult to secure installation space in urban areas. Even if it can be secured, the installation cost is very high.

SUMMARY OF THE INVENTION An object of the present invention is to provide a power cable wind cooling system in a canal which can efficiently, space-saving, and economically cool a power cable laid in the canal. .

[0011]

SUMMARY OF THE INVENTION An in-cavity power cable air cooling system provided by the present invention is directed to a system for cooling a power cable by blowing air into a cave where the power cable is laid. Compressed air is stored in a tank, and the compressed air is released into the sinus passage when necessary.

By installing the compressed air storage tank and the air compressor underground, it is possible to cope with space saving on the ground.

Producing compressed air at night when power demand is low,
This is stored in a compressed air storage tank, and when the compressed air is released during a time when the power demand reaches a peak, efficient operation can be performed.

[0014]

FIG. 1 shows a preferred embodiment of a power cable air cooling system in a sinus according to the present invention.

The in-cave power cable air cooling system of this embodiment has a compressed air storage tank 11 and an air compressor 12 installed underground, and the compressed air stored in the compressed air storage tank 11 is supplied to the inside of the cave 13. So that it can be released.

The following operation is performed by the above-mentioned equipment. Air compressor 12 is supplied by nighttime power with little power demand.
Is operated to produce compressed air, and the compressed air is stored in the compressed air storage tank 11. Then, during a time period when the power demand peaks; in the afternoon during the day, the compressed air is stored in the compressed air storage tank 11. The compressed air that has been set is released into the tunnel 13 to blow air into the tunnel 13. Since the released compressed air has a property of decreasing the temperature due to the compressed gas expansion, it is possible to efficiently cool the power cable laid in the sinus.

According to the power cable air cooling system in the tunnel which is operated as described above, the following operational effects can be obtained.

(1) Compressed air is produced during the night when power demand is low, stored in a compressed air storage tank, and when the power demand reaches a peak in the afternoon during the day, the compressed air is introduced into the tunnel. By releasing the air, air is blown into the cave. By opening the compressed air stored in this way, there is no need to use the electric power to operate the blower during the peak power demand period, and it is not necessary to install the blower on the ground. And space saving.

(2) When the compressed gas is released, there is a physical characteristic that the temperature of the gas is rapidly cooled. Since the cooled air is blown into the tunnel, the cooling capacity is very high, and the cooling efficiency is high. Further, according to this cooling method, there is no need to cool the outside air with a cooling facility using electric power at the peak of electric power demand, so that energy is saved and economical advantage is great.

(3) By installing the compressed air storage tank and the air compressor underground, it is not necessary to install equipment such as a cooling tower and a blower fan on the ground, and the space can be saved. This is very effective where space cannot be secured on the ground.

[0021]

As described above, according to the present invention, there is provided a power cable wind-cooling system in a tunnel which can efficiently, space-savingly and economically cool a power cable laid in the tunnel. To achieve the intended purpose.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an embodiment of a power cable air cooling system in a sinus according to the present invention.

FIG. 2 is an explanatory view showing a first example of a conventional power cable air cooling system in a canal.

FIG. 3 is an explanatory diagram showing a second example of a conventional in-cavity power cable air cooling system.

FIG. 4 shows a third example of a conventional power cable air cooling system in a canal, where (A) is an explanatory diagram of the entire system and (B) is an explanatory diagram of a main part.

[Explanation of symbols]

 11 Compressed air storage tank 12 Air compressor 13 Cave

Claims (3)

[Claims] A system for cooling a power cable by blowing air into a passageway in which the power cable is laid, wherein compressed air is stored in a compressed air storage tank.
A power cable air cooling system in a sinus, wherein compressed air is released into the sinus when necessary. 2. The system according to claim 1, wherein the compressed air storage tank and the air compressor are installed underground. 3. Producing compressed air at night when power demand is low,
The power cable air cooling system in a tunnel according to claim 1 or 2, wherein the compressed air is stored in a compressed air storage tank, and the compressed air is released during a time when the power demand reaches a peak.