JPS5914313A - Method of cooling of cable - 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 cooling method for locally and directly cooling an OF cable junction box and a cable near the junction box, and an object thereof is to provide an efficient cooling method.

Generally, OF cables are cooled to suppress temperature rise during operation. For example, the cable section can be cooled by direct water cooling or indirect trough cooling, but the terminal connection box,
The connection boxes between the cables cannot be cooled, and as a result, the cooling box and the cables (10-order) near the cooling box become hot, and the temperature rise in this portion may become a cause for limiting the allowable current.

The present invention effectively cools the junction box and the cable by locally cooling the junction box and the conductor near the junction box using a direct cooling method, and an embodiment thereof will be described below with reference to the accompanying drawings.

The cable is made by forming an insulating layer on the outer periphery of a stranded conductor 2 having an oil passage 1 by wrapping all the layers of insulating paper tape, and further covering the outer periphery with an aluminum sheath 4. In the terminal junction box 5, the above aluminum sheath 4 is After being removed, the conductor 2 is reinforced with a paper insulating layer 6 and housed in the insulator tube 7. At the end of the conductor 2, the oil passage hole is closed and the conductor pull-out rod 8 protrudes above the connection box 5, allowing oil to pass through. The path 1 communicates with the inside of the junction box 5 through an oil port 9 provided on the side of the conductor.

An oil port 10 is provided in the sheath 4 at the appropriate position of the cable, and the oil port 10 and the connection box 5 are connected by a circulation pipe 13 having a pump 11 and a cooler 12 in the middle. Cooler 1
The insulating cooling oil cooled by step 2 enters and exits from the oil pipe 10, passes through the insulating layer 3, and is sent into the oil passage l of the conductor 2, from the cuff 9 of the junction box 5 through the inside of the junction box 5 to the pump 11.
1 In this way, the conductor 2 from the cuff 10 to the cuff 9 is cooled by the cooling oil cooled by the cooler 12.
It is possible to directly and effectively cool the cable conductors in other parts, and also to provide good results to the cable conductors in other parts, thereby eliminating problems caused by temperature rises in the cables inside the junction box and in the vicinity of the junction box.

As an example, 154KV, lX2500mJ, power transmission valley J1
When using a 660MVA direct water cooling cable without cooling,
The temperature of the conductor is 103℃ at the terminal junction box and 91℃ at the cable part, and in order to cool this down to the allowable temperature of 85℃ or less, it is necessary to cool the terminal junction box: 140W for 4m, the cable 120W for 10m, totaling 260W. The flow rate of cooling oil required for this is 4.6 ca, assuming the inlet side oil temperature is 50℃ and the river mouth side oil temperature is 80℃.
r/sec.

Further, the oil pressure for circulating the cooling oil is mostly the oil pressure consumed for passing the cooling oil through the insulating layer, and is less than IK9/c+ii degrees, although it depends on the material and thickness of the insulating layer. Therefore, a small pump is sufficient, and since the cooling oil is for local cooling, a relatively small amount is required, and cooling can be achieved with small equipment. Both the cable and the connection box are ordinary ones, and you can expect a highly efficient cooling effect.

Note that the above embodiment is an example, and the flow direction of the cooling oil may be opposite to that shown in the drawings, and may be made to pass through the insulating layer on the outlet side.

Furthermore, the connection box is not limited to the terminal connection box shown in the diagram.
Terminal connection box as oil inlet/outlet G-1) Cable cuff terminal connection box
Cable Junction Box Cable Junction Box Gu--) Cable Junction Box Cable Junction Box Cable Cuff Cable Cuff Ri-One Suitable for local cooling of all combinations of cable cuff and shade.

[Brief explanation of the drawing]

The drawings are explanatory diagrams for carrying out the invention.

Claims (1)

[Claims] A method for cooling an OF cable, characterized in that the conductor is directly locally cooled by sending or collecting cooled insulating oil through the insulating layer of the cable into the oil passage of the conductor.