JPS6324510A - Bushing for high voltage - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides bushings, especially transformers, choke coils,
The present invention relates to a high-pressure bushing for connecting electrical equipment insulated with inert gas under high pressure, such as a measuring transducer, a capacitor, or a switchgear. This type of bushing consists of a high-voltage conductor and an air insulator tube attached to the outside air side, and electrodes for controlling the electric field are arranged inside the air insulator tube or mantle tube. It is set up. The interior space of the bushing is filled with an inert gas such as sulfur hexafluoride (SF6) at low pressure.

Such bushings are used to form electrical connections, i.e. conductive connections, between electrical devices such as transformers, choke coils, measuring transducers, capacitors, or to connect locations located in the open air from switchgear. Connections to, for example overhead circuits, or in the case of test transformers: two, high voltage connections to the test vessel are made.

All equipment and devices mentioned above are insulated with inert gas at high pressure.

PRIOR ART Pneumatic side tubes or mantle tubes, especially those used in open air, are of porcelain body with ribs and are otherwise of high quality: nevertheless. , has the disadvantage of low burst pressure strength, so the internal gas pressure is kept as low as possible, as long as it is sufficient for air, which has only a small dielectric strength, acting from the outside. There is.

From German patent application No. 2 627 653, an outdoor high-voltage bushing for gas-insulated electrical installations comprising:
Bushings are known which include a conductor rod in the center and an outer shell tube which provides protection against external atmospheric influences. The separation or isolation between the high pressure of the gas in the connected electrical equipment and the desired lower pressure of the gas in the side shell is arranged in parallel and coaxial relation to the outer side shell. This is achieved by means of a second shell insulator made of a high pressure-resistant connecting material, for example a glass fiber-reinforced synthetic resin.

In this way, the problems of sealing the outer air-side insulator tube (-limited breaking strength) are solved. It has been found that this method has the disadvantage of high technical costs for producing the tube.

OBJECTS OF THE INVENTION An object of the present invention is to provide a bushing that uses less material and occupies less space when two or more than three electrodes are used in the insulating mantle tube.
The object of the present invention is to improve this by providing a device that reliably prevents high gas pressure from acting on the fragile insulating mantle tube.

According to the present invention, the problem in the structure of the invention is solved by the structure described in the so-called characteristic part of claim 1.

The improved push-button of the present invention allows one or more sealing rings to automatically establish a gas-tight connection between two adjacent electrodes under high gas pressure. In this case, the electrode or its metal sleeve and its perforation plate form a pressure gas envelope and therefore, in particular in the form of a sealing cap (=some second
A shell tube is formed, thereby avoiding the risk that the seal between the high-pressure space and the low-pressure space will result in an unacceptable pressure leak.

Advantageous embodiments of the invention include the following claims:
Two are described. The embodiments of Kinoshi and Akira will be described in detail below with reference to the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 a high pressure compressed gas condenser is shown, reference numeral 1 designating a metal flange. “This metal flange is the pressure vessel 2 of the high pressure compressed gas condenser.
．． and are connected in a pressure-tight manner. Flange 1 has
Through the annular seal 3 an air side tube or a mantle tube in the form of a porcelain tube is arranged and fixed in the usual manner by means of mounting screws 5. .

A high-voltage conductor 6 extends through the center of the flange 1 and the mantle tube (air side tube) 4.

The pressure vessel 2 is arranged in a frame structure provided with wheels.

The upper end of the mantle tube is closed by a cover plate 7, and the high voltage conductor 6 is connected to the nuclear force 2-plate 7. ．． and is held by the cover plate. The Z-plate 7 carries a centrally disposed cylinder 8 with arms 9, on which are placed high voltage shielding electrodes 10° located opposite each other. 11 are provided.

The opening of flange 1 has 1. Ring-shaped termination electrode 12
An electrode 12.13 with a, 13a is arranged in concentric relation to the high voltage conductor 6.

In this case, the outer electrode 12 is provided on the ring 1-4,
This ring 14 is attached to the flan 1 with a seal interposed therebetween. The electrodes 1.2, 13, which can be constructed, for example, from aluminum tubes of different lengths, are captured at the upper end by a metal ring 16 and held at a predetermined distance by a spacer member 18. A perforated plate 19 is disposed between the rings 16 in an airtight manner to isolate the two gas spaces at different pressures.

The structure of the retention of the electrodes 12, 13 and the spacers 18 and perforation plates 19 used in connection therewith is clearly seen in FIG. 2, which shows one embodiment of the invention. This figure shows an embodiment of the invention comprising two concentric electrodes 12,13 with different lengths. However, the present invention provides two
The present invention is not limited to such embodiments with two electrodes. Depending on the voltage level, three or more electrodes can be provided.

As shown in FIG. 2, the electrodes 12 and 13, which are mounted in an insulating manner on the flange to which the earth potential is applied, are each provided with one gold B ring 16 on their end side. They are formed in a T-shape and are rounded in the direction toward the electrodes, forming shoulders 16a for the perforation plates 19 made of cast resin and used to form the compressed gas mantle. Since this perforation plate 19 has the form of a truncated cone-shaped mantle, a conical body that increases the creepage distance is obtained.The inner and outer edges (bent These curved edges are connected to the shoulder 16 of the metal ring 16 with intervening seals, rings 17a, 17b, each configured as a face seal.
a, and are pressed against the seal rings 17a and 17b due to the pressure difference between the high pressure on the equipment side and the low pressure of the insulating gas inside the mantle tube (air side tube). There is.

During storage before use of the bushing and during transport of the bushinder, the perforation plate 19 is pressed against the sealing ring 17a or 17b, respectively, by a holder which is used as a ring electrode 2o. These ring electrodes 20 form a protrusion with a large radius on the device side, and each ring electrode is provided with a groove 20a in the center of the ring 16 having a T-shaped cross section. Engaged with the legs, the electrode 20 is retained by socket cap screws 20b.

The end surface of the curved part of the hole plate 19 (= is the metal sleeve 19c
, 19d are advantageously cast.

A spacer 1 configured as a cast resin ring to keep the electrodes 12.13 apart within the low-pressure chamber of the mantle tube.
8 is used, and this spacer 118 is provided with through openings 18a or corresponding holes distributed around its periphery. The spacer element 18 is configured as a perforated plate with a conical shape and a beveled end, and on the end side the control electrode 12.1
3+= Supported by the disposed metal ring 21 and connected to the cap head screw 23 via the ring-shaped electrode 22
It is fixed to the metal ring 21 by. At the side of the inner edge, which is preferably made of metal and is provided with a metal sleeve 18b, the spacer member 18 rests with play against the next smaller electrode 13, so that the electrode 13 rests against the inner edge 18.
It can be slid with b.

In the pressure-tight connection shown in FIG. 3, as a variant of the embodiment shown in FIG. Perforated plates 19a, 19b are arranged one above the other in the direction of the electrodes 12.13.The outer electrode 12 is gripped at its end by a metal ring 16 which is provided with a shoulder 16a. The portion of the electrode 13 located on the other inner side that is opposed to the metal ring 16 is divided by a metal ring 24 having a shoulder portion 24a. The side that abuts is chamfered, and together with the peripheral notch 24b formed on the outer surface of the metal ring 24 and the peripheral notch 16b formed on the inner surface of the metal ring 16, a hollow chamber is formed. A seal ring 17 is formed in these hollow chambers.
A and 17b are filled respectively. these seals
The ring is formed as a circle. The mechanical hardness of this O-seal ring is adapted to the pressure characteristics acting on it.

In a similar manner, gold J is placed between electrode 13 and the other electrode.
A pressure-sealing mantle is formed by providing an IJ ring and a perforation plate.

Advantageously, the inside and outside of the insulating perforation plates 19a, 19b are captured by metal sleeves QC, 19d. A simple formation of the cutouts 16b, 24b in the metal ring 16.24 can be achieved by forming them in the form of grooves. In this case, by simply chamfering the metal sleeves I9c, 19d, a rhomboid-straddling square cross section is obtained for the hollow chamber or cutout 16b, 24b for accommodating the sealing ring 17a, 17b.

Shoulder 1 on the low pressure side of the metal ring 16.24 as a limiting stone ξ of the perforation plates 19a, 19b in the upward direction
6a as well as 248 are advantageously provided.

If sufficient gas overpressure is not applied, the perforation plate 19a
, 19b as well as to securely hold these perforation plates during transport, a circumferential cutout 24C for a snap ring 24d or a curved mechanical connection element is provided on the high-pressure side of the metal ring 24. is provided.

When assembling the hole plates 19a, 19b and the metal ring 16,24, the gaps between these elements or members are filled with a paste consisting of vaseline mixed with titanium dioxide (Rutil J). , it is preferable to keep the gaps dielectrically short-circuited. However, basically, the insulating perforated plates 19a, 19t:+ each have a circumferentially extending rib on one side to achieve a long creepage distance. 26 and an annular groove 25 on the opposite side, the insulating gas used is sufficient to achieve sufficient dielectric strength.

The invention allows the use of any number of control chambers/poles. In this case, by fine-step control of the electric field, a very small diameter for the outer shell is possible, thereby significantly reducing material consumption. High voltage conductor 6
The electrodes 12.13 can also be insulated by an insulating gas with a freely selectable pressure, for example around 2.5 par in the high pressure region. On the other hand, it is expedient to use a porcelain insulator 6 (=atmospheric pressure or a slightly higher pressure, such as about 0.5 pulsatility), or an insulating gas.

The lower electrodes provided on the electrodes 12.13 are known shielding electrodes 12a, 13a for equalizing the electric field. These shield electrodes are connected to the control terminal 12.13 and the pin 12.
b, 13b may be mechanically connected or may be joined. The metal sleeves 19C, 19d can be similarly bonded to the perforation plates 19a, 19b, but are preferably formed by casting.

The invention is particularly applicable to all types of gas insulated bushings commonly used at high to very high voltage levels. However, the invention is not limited to such applications.

Effects of the Invention According to the invention, a bushing of the type mentioned at the outset can be installed in an insulating mantle tube, which requires less material even when two or more electrodes are used, occupies a small space, and is fragile. A high-pressure bushing can be obtained that occupies a small space and has a robust structure, which can be improved by providing a device that reliably prevents high gas pressure from acting on the bushing.

[Brief explanation of drawings]

1 is a diagram schematically illustrating a pressure-tight connection arrangement between electrodes of a high-pressure compressed gas condenser;
FIG. 3 shows the structural configuration of a pressure-tight connection of 22 electrodes to form two pressure spaces in the configuration shown in FIG. The figure shows a modification of the construction of a pressure-tight connection of two electrodes to form two pressure spaces. 1... Metal flange 1, 2... Pressure vessel, 3...
Ring-shaped seal, cow... mantle tube, 5... mounting screw, 6... high voltage conductor, 7... cover plate, 8...
Cylinder, 9... Arm, 10.11... High voltage shielding electrode,
12, 13... Electrode, 16.24... Metal ring,
17... Seal ring, 18... Notch, 18b.
・・Metal three 2.19a, b... Drill plate, 19C・
...Metal ring, 20...Ring electrode 1.20a...
・Groove, 21... Metal/metal ring, 22... Electrode, 23
...Cap head screw, 24C...notch, 2
4d... Holding element, 26... Lip

Claims (1)

[Claims] 1. A bushing for connecting an electrical device insulated with an inert gas under high pressure and having a connection point located in the outside air, such as a high-voltage bushing. , with one or more tubular electrodes to control the electric field between the high voltage conductor to which high voltage is applied and the flange to which earth potential is applied, in order to keep the burst pressure as low as possible In said bushing, which comprises a mantle tube filled with an inert gas at low pressure, a flange (1) to which earth potential is applied, and one or more electrodes (12, 13) and a high voltage conductor (6 ), an insulating perforation plate (19; 19a, 19b) is disposed between the two, and the perforation plate separates the high gas pressure on the equipment side from the low gas pressure inside the mantle tube (4), making them airtight with each other. and a bushing for holding the electrodes (12, 13) at a predetermined radial interval. 2. A narrow metal ring ( 18), and the ring is provided with a seal (17).
A, 17b) is provided with a notch, e.g. a groove, to accommodate the insulating perforation plate (19; 19a, 19b) due to the pressure difference between the high pressure on the equipment side and the low pressure inside the mantle tube (4). The bushing according to claim 1, which is pressed against the seal. 3. The perforation plate (19) is sealed with a seal (17a) to keep the bushing structure fixed during transportation in an unassembled state
, 17b) according to claim 1 or 2, which is pressed against the bushing. 4. The inner side of the bushing of the metal ring (16) is chamfered, and the metal ring is provided with a large radius overhang on the device side or in another ring. The bushing described in any of the above. 5. The seals (17a, 17b) are flat rings or O
5. A bushing according to any one of claims 1 to 4, which is configured as a ring. 6. Claims 1 to 5, wherein the perforation plate (19) is made of cast resin and has a bent portion at its edge so as to form a cone that increases the creepage distance. The bushing described in any of the above. 7. If the seal (17a, 17b) is formed by an O-ring, an additional ring with a corresponding cutout, e.g. a groove, is used, so that the O-ring is at least partially pressed against the cylindrical surface The bushing according to any one of claims 1 to 6, wherein the bushing has the following features. 8. Attach a metal ring (19) to the end surface of the bent part of the perforation plate (19).
The bushing according to any one of claims 1 to 7, wherein c) is formed by casting. 9. Inside the mantle tube (4), the electrodes (12, 13) facing the perforation plate (19) in order to maintain the radial spacing of the one or more tubular electrodes (12, 13); A narrow metal ring (21) is provided at the end, and the ring includes:
A conical spacer (18) in the form of a perforation plate is mounted, which abuts with its inner surface (18b) the electrode (13) of the next smallest diameter, so that said electrode (13)
9. A bushing according to any one of claims 1 to 8, wherein the bushing is slidable on the surface (18b). 10. Two perforation plates (19a, 19b) are arranged between two adjacent electrodes (12, 13) one above the other in the direction of the electrodes (12, 13), and the electrodes are arranged in the horizontal dividing plane, respectively. The seal ring (17) together with the rings (16, 24)
The bushing according to any one of claims 1 to 9, forming cutouts (16b, 24b) for the bushings (a, 17b). 11. The metal rings (16, 24) are connected to the perforation plate (
Shoulders (16a, 24a) as stoppers for 19)
A bushing according to any one of claims 1 to 10, comprising: 12. A metal ring (16, 24) is provided on the high-pressure side with a holding element (24) for mechanically prefixing the perforation plate (19).
Bushing according to any of claims 10 to 11, comprising a circumferential cutout (24c) for d). 13. Claim in which the perforation plate (19) is provided with an upper surface with an elongated creepage distance, for example a circumferential rib (26) on one side and a circumferential ring groove 25 on the opposite side. The bushing according to any one of the ranges 1 to 12.