KR820001331B1 - Contact-type bushing - Google Patents

Abstract

The transformer tank(1) has a support(2) with an inner & outer flange(3) against whose inner edge is screwed a support (4) for guiding a conductor end(5). The support(4) is made of an insulating material and seals the oil filled transofrmer tank from the end of the safety chamber(15). Opposite the support(4) at the other end of the safety chamber is a further support(9), whose outer rim is held at the end of the outer sheath(6) of a sulphur hexafluoride insulated cable, by a ring(22) on a flange(10). The support(9) guides a conductor end(7) of this cable, whose core is surrounded by a protective sheath(8). The safety chamber(15) is constructed with a bellows at the center(11), and a flexible conductor(12) connects the conductor ends.

Description

Bushing for connection

1 is a cross-sectional view of an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state when testing what is shown in FIG.

The present invention relates to the installation of a safety room between a transformer and a facility part connected thereto in a high voltage bushing for connection between an insulating fluid encapsulated transformer and an SF ₆ gas insulated cable or a copper switching device. As the load density of the power transmission network increases, it is necessary to transmit power at a high voltage as close as possible to the user.

In consideration of the large area for the high-voltage switchgear according to the high-voltage transmission and delivery, gas-insulated sealed switchgear is sometimes employed in densely populated areas.

According to a paper on bushings for equipment using SF ₆ gas as an insulating medium, ETZA Vol. 94, P 423-426, it is known to install special bushings for the connection of individual switching equipment components. Similarly for the connection between the oil insulator and the SF ₆ gas insulator, a bushing with a safety chamber for sealing SF ₆ gas is known.

This safety chamber must prevent the explosion of high-pressure protective gases, especially when the bushing is cracked.

The disadvantage of using this type of bushing is that a conventional air-oil insulating bushing must be fitted in place of this particular bushing in the testing of transformers or hermetic switchgear components at the factory. Testing of transformers or plant components in the operational arrangement at the final installation site is not possible unless the arrangement of the switchgear components is changed when using this special SF ₆ -oil insulation bushing.

The present invention aims to provide a simple and easy-to-assemble bushing for use in an insulating oil encapsulation transformer of a closed switchgear, in particular a bushing having a separating portion of a switchgear component for testing.

According to the present invention, both ends of the axial direction of the safety chamber enclosed with an insulating fluid are partitioned by a support for the conductor ends, and the outer surface thereof is a bellow-shaped flexible material that is stretched laterally. Enclosed in a sieve, draining the insulating fluid from the safety room, removing the bell-shaped flexible body, and electrically connecting the conductor ends without changing the positions of the transformer and the parts connected to the transformer. This can be achieved by being able to remove the flexible conductor.

According to an advantageous development of the present invention, both ends of the bellows-shaped flexible body are fixed by mounting bolts to a flange supported by the support body at the operating partner of the facility, and the bellows-shaped flexible body is peeled off at least once. It is configured to be supported by an auxiliary bolt. The flexible conductor in the safety room is made of a conductive material and is enclosed by a barrel made of a sliding material, which is fixed to the end of the conductor supported by the support so that it can be easily detached by a screw or plug connection. It is good.

According to another configuration of the present invention, after removal of the flexible conductor, the transformer-side conductor end is shielded by a cap having a flat plate and the other conductor end is curved in a round shape, and the flexible conductors are twisted together around the cavity axis. It is formed by a freestanding partial conductive material, and the passage of the sliding material in the shape of a flexible conductor and a barrel is mutually supported and guided through a gap ring.

According to the high pressure bushing according to the present invention, the sealed opening and closing facility can achieve good space utilization and economical configuration.

In addition, according to the bushing of the present invention, the test of individual component parts can be carried out without using a special temporary bushing or a conventional bushing temporarily prepared for the test purpose.

Thereafter, since the arrangement of the plant components is not necessary to be inserted at the time of insertion of a new bushing, retesting at the installation site can be performed without difficulty and without arrangement.

Next, embodiments of the present invention will be described in detail with reference to the drawings.

Fig. 1 shows the cross section of the completed high voltage bushing, and Fig. 2 shows the cross section of the same high voltage bushing after preparation for disconnection test of adjacent switchgear components.

The transformer tank 1 showing only a partial cross section has a connection part 2, which is provided with a flange 3 which protrudes inward and outward facing the end thereof, On the inner side with respect to the inner end, a support 4 for supporting the conductor end 5 is attached.

The main body 4 becomes an insulator, and isolate | separates and isolates the edge part of the transformer tank 1 filled with oil, and the safety chamber 15.

The support 9 is arranged at the other end of the safety chamber 15 opposite the support 4, the outer edge of which is supported on the flange 10 at the end of the outer cylinder 6 of the SF ₆ gas insulated cable by a ring 22. have.

The support body 9 is insulated from the cable chamber filled with the pressurized SF ₆ and the safety chamber 15.

The support 9 supports the conductor end 7 of the cable, and the main body of the cable is surrounded by a protective cylinder 8.

The safety chamber 15 between the support body 4 and the support body 6 is surrounded by a bell-shaped flexible body 11 with respect to the outside in the radial direction.

The end of the bellows-shaped flexible body 11 provided with the flange is supported by the flange 3 or the ring 22 by the mounting screw 16. A screw connecting member 17 is mounted on the conductor end 5 protruding into the safety chamber 15.

Also in the other end of the safety chamber 15, the conductor end part 7 is provided with the screw connection body 18 similarly.

These screw connectors 17 and 18 support the ends of the flexible conductor 12. At the end of the flexible conductor 12, a positioning ring 14 is installed outside the connecting bolt protruding into the screw connecting body.

The flexible conductor 12 is aggregated in the middle part by the many self-supporting partial conductor twisted on the common axis.

Therefore, in the range of the safety chamber, the conductor end 5, the screw connection 17, the flexible conductor 12, the screw connection 18, and the conductor end 7 form one almost straight straight conductor. This straight through conductor is shielded by a cylinder 13 supported on the positioning ring 14.

The barrels 13 are of different diameters and are forbidden to interlock with telescopic barrels.

A passage 19 extending from the flange 3 to the interior of the connection part 2 is provided for the acceleration / deceleration or ventilation of the safety room, which can be closed by a cover not shown.

2 shows that the flexible conductor 12 and the tube 13 are removed in the same structure.

In this case, since the conductor ends 5 and 7 are electrically disconnected, the equipment parts belonging to them can be tested.

In order to better shield the conductor end 5 and the conductor end 7 from each other, a flat plate 20 is attached to the conductor end 5 and a hemispherical cap 21 is fixed to the conductor end 7. It is.

To remove the flexible conductor 12 and the barrel 13 separately, the passage 19 is first opened to drain the transformer oil from the safety chamber 15, and then the flanged end of the bellows flexible member 11 is opened. Peel alternately. By alternately releasing the ends of the bell-shaped flexible body 11, the screw contact bodies 17, 18 and the cylinder 13 are sequentially touched, and these can be disassembled.

After removing these components from the safety chamber, the flat plate 20 and the cap 21 are fixed to the screw connectors 17 and 18 instead of the ends of the flexible conductor 12. At this time, the plate 20 is again grounded via the wire 23 and the ground bolt 24 at the connection in the transistor 3.

The safety chamber 15 is injected with oil through the passage 19 and exhausted through the other passage 19.

As a result, adjacent plant parts are electrically isolated from each other. After the test is completed in this connected state, the flat plate 20 and the cap 21 are removed in the reverse order to the above, and the flexible conductor 12 and the tube 13 are mounted again.

Claims (1)

In the bushing for connecting the insulating fluid encapsulation transformer and the SF ₆ gas insulated cable or switchgear, an insulating oil encapsulation safety chamber 15 is provided between the transformer and the switchgear connected to the transformer, and both ends of the safety chamber in the axial direction. The silver is partitioned by the supports 4 and 9 of the conductor ends 5 and 7, and the outer surface is surrounded by a bellow-shaped flexible body 11, which is stretched and contracted in the axial direction, and the insulating fluid in the safety chamber 15. Discharges the bellows-shaped flexible body 11, and then electrically connects the conductor end portions 5 and 7 without changing the position of the transformer 1 and the opening / closing installation portion 6 connected thereto. A bushing for connection, characterized in that the flexible conductor (12) connected by means of removal can be removed.

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