JPS6285617A - Self-cooling type terminal joint box of power 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 gas/liquid circulation self-cooling type roadside junction box that utilizes natural convection for power cables.

For large-capacity power transmission cables (cross-linked polyethylene insulated vinyl sheathed cables, oil-filled cables, etc.), a method is adopted in which the cable itself is directly or indirectly cooled with water or the like in order to suppress an increase in resistance due to heat generation in the cable. In this case, the capacity of the cable itself can be increased by forced cooling, but unless the capacity of the cable termination junction box can be increased, it is impossible to increase the capacity of the system as a whole.

For this reason, in the past, the conductor of the cable at the terminal connection part was made larger.1. It is necessary to reduce loss in the termination box or introduce a forced cooling system, but the former requires a different diameter joint, and the latter two require specialized equipment [~, larger junction boxes, It is extremely disadvantageous in terms of economy, ease of maintenance, and long-term reliability.

Objective d of the present invention: To provide a self-cooling air-based, large-sized, oil-submerged termination junction box that is highly reliable, economical, easy to maintain, relatively compact, and has an excellent cooling effect.
The goal is to achieve a larger power transmission pull capacity.

According to the present invention, in a self-cooling type air or oil submerged terminal connection box that utilizes natural circulation, electricity is applied vertically to secure the flow path! The above objective is achieved by utilizing a double inner and outer insulator with three shields.

The present invention will be described in detail below based on embodiments shown in the drawings.

FIG. 1 is a partial sectional view showing one embodiment of the present invention. In Figure 1, an oil submerged terminal connection box is shown (7), and its drawing is concentrically carved 't;'; Tchi4=). - Only a part of the right 21 of the mate is shown in cross section; g > f:) 1st
It's on the diagram, but it's incomplete.

The connection box goes up to the oil thread part 10 and is separated into the cable main body part and the terminal part side. -(-iro. Insulation -L of the cable 1 having a hollow channel at the end with a font t' + j dedication 2, an insulation reinforcement, a hawk world relaxation part born from V3 and Kurumaus 4 is arranged. 1, - 1 lower bell on the outside of the tenni j, 15 and - (embedded in the second part 2・-ru t
The inner insulator tube 5 and the outer insulator tube 6, which are made of resin and have a diameter of 5-j'V', are arranged at the same angle. , The radiator 7 is still functioning in the m section of the insulator tubes 5 and 6 between the middle part of the conductor pull-out rod 2 and the outer insulator tube 6, and the lower part of both secondary insulator tubes (1- is the oil connecting tube 8 Establish L], connect the former and open the OF oil)! : : :, = 1.1 oil, etc., near i):, ↑ is filled with edge 9. The insulating oil 9 passes through the gap between the cable 1 and the inner insulator tube 5, and the cable 1 is heated. J.

The radiator 7K is guided through the inner 2 part of the hollow conductor pull-out rod 2 that can be connected to the end, and the gap between the inner porcelain tube 5 and the outer porcelain tube 5, the ball, etc. and connecting pipes 13 and 1) form a circulation loop as shown by the arrow.

According to such a configuration, the heat generated by the current flowing through the conductor of the cable 1 is absorbed by the insulating oil 9 in the gap between the cable 1 and the inner insulating tube 5 through the insulator of the cable 1, and its temperature is increased. to rise, swell, and expand. As a result, the specific gravity of the insulating oil in this portion decreases and rises toward the radiator 7. Thereafter, as before, the insulating oil, which is heated by the radiator 7 and whose specific gravity has increased, descends according to gravity through the gap between the inner insulator tube 5 and the outer insulator tube 6, and circulates through the connecting tube 8.

In terms of electric field, if the lower part of the inner insulator tube 5 and the closed mouth 15 are not present, the electrode part of the closed mouth 4 will be shielded by a current shield installed at the lower part of the outer insulated tube 6.
Since the inner insulator tube 5 is separated by the distance and a sufficient shielding effect cannot be obtained, it is necessary to increase the curvature of the tip of the bell mouth 4. However, in the present invention, it is necessary to increase the curvature of the tip of the bell mouth 4. The lower bell mouth 15, which has now changed, does not cause the above-mentioned problems.

FIG. 2 is a diagram similar to FIG. 1 showing another embodiment of the present invention, and the same numbers indicate the same or similar parts. Figure 2/No') 1 case per case, q wooden drawer (ho 2
The hollow and the rl-yo, sixty-two, the action of one ripening is outside 141
I4. It was ()
, the implementation i''' in Figure 1 has a somewhat cooling effect compared to 1:
As the temperature decreases, it is still necessary to provide a sufficient cooling effect. Although it is possible to improve the efficiency of the present invention by using the inner insulating tube needle as a partition wall of the insulating oil optical path, the construction is simple!1. It is easy to maintain, has self-cooling effect, is economical, and has an oil-immersed terminal connection (can be obtained with a hollow box).

[Brief explanation of drawings]

The first is an unexploded, schematic cross-sectional view of one embodiment from China, and the second is a similar diagram of another embodiment. 5, 1... Cable, 2... Conductor pull-out rod , 3... Insulating reinforcing layer, 4.15
・・Bell mouth, 5・・Inner insulator, 6・/78 go 111
1. Insulated pipe, 7... Heat sink, 8. Access pipe, 9... Oil-free, 10... Oil-tight part, 11... Cable refrigerant, 25
...embedded seal tF. Agent Patent Attorney Sato

Claims (3)

[Claims] (1) A double inner and outer insulator tube, a cable inserted into the inner insulator tube, an electric field relaxation part formed on the insulator, a conductor pull-out rod connected to the conductor of the cable, and the cable and the electric field relaxation part. an insulating gas/liquid filled in a first gap between the part and the inner insulator tube and a second gap between the inner insulator tube and the outer insulator tube, and a heat radiating part provided at the top part to radiate heat from the insulating gas/liquid;
a connecting pipe that communicates the first and second gaps at the lower part, the insulating gas/liquid passes from the first gap along at least a part of the conductor pull-out rod, and further includes a connecting pipe that connects the first gap with the second gap, and a connecting pipe that connects the first gap with the second gap; passing through the second gap and the connecting pipe;
A self-cooling type terminal junction box for power cables, characterized in that the power cable can circulate and flow through the first gap. (2) The heat radiating part is a radiator provided at the top, and the insulating gas/liquid flow path along the conductor pull-out rod is provided inside the conductor pull-out rod and communicates with the upper part of the first gap. A self-cooling type terminal junction box for power cables according to claim 1, characterized in that: (3) Claims characterized in that the heat dissipation portion is formed by a portion of the pull-out rod, and the insulating gas/liquid flow path along the conductor pull-out rod is provided along the surface of the conductor pull-out rod. A self-cooling type termination junction box for power cables as described in item 1.