EP2109870A1

EP2109870A1 - Pole for a gas-insulated high-voltage switch and method for producing a switch pole of this type

Info

Publication number: EP2109870A1
Application number: EP08701261A
Authority: EP
Inventors: Stephen Clifford; Christian Franck; Magnus Olofsson; Leopold Ritzer; Marco Schneider
Original assignee: ABB Research Ltd Switzerland; ABB Research Ltd Sweden
Current assignee: ABB Research Ltd Switzerland; ABB Research Ltd Sweden
Priority date: 2007-01-17
Filing date: 2008-01-07
Publication date: 2009-10-21
Also published as: WO2008087060A1; CN101584013A; WO2008087060A8; EP1947669A1; CN101584013B

Abstract

The switch pole of a high-voltage switch contains an insulating housing (1) filled with insulating gas, two power supply connections (2, 3) that run through the wall of the insulating housing (1) and an electrically conductive contact assembly that is connected to the two power supply connections. The insulating housing (1) has a shell-type construction and has an inner and an outer shell. The outer shell is configured as an insulator (30), is cast onto the inner shell and supports the latter against a force that is caused by the pressure of the insulating gas. The inner shell is configured as a gas-tight sealable container (20) prior to the casting of the outer shell. Prior to said casting process, the housing (20) holds at least the contact assembly and at the same time has a degree of shape retention that is sufficient to support its own mass and all the parts held in said housing. The switch pole can be cost-effectively produced and is characterised by a high degree of operational safety.

Description

Pole for a gas-insulated high-voltage switch and method for producing such a switch pole

TECHNICAL AREA

The present invention relates to a switch pole for a

High-voltage switch according to the preamble of patent claim 1 and to a method for producing the switch pole. Under high voltage switch here are understood switch, which are generally used in the voltage range greater than 36 kV and in particular greater 72 kV and which an insulating gas, such as typically SF ₆ , to isolate the current-carrying

Have components and for blowing a occurring during a switching arc.

STATE OF THE ART

Insulating housing for switch poles of the aforementioned type are described in CH 538 168 A and DE 12 43 762 B. These insulating housing are constructed shell-shaped and each have an inner and an outer shell, of which the outer shell is designed as an insulator and the inner shell embedded and supported against a force caused by the pressure of the insulating gas force, the insulation shown in CH 538 168 A consists of two

Housing halves made of electrically insulating, hardenable plastic. The two housing halves are screwed together by means of a flange connection. The wall of the two housing halves is manufactured in a three-step casting process in which an inner layer is first cast, then a middle layer is poured onto the inner layer and finally an outer layer is poured onto the middle layer. The housing is characterized by a high mechanical strength. Connection bolts for a contact arrangement to be provided in the housing and a feedthrough tube for an actuating shaft from a switch drive to the contact arrangement are encapsulated during casting of the housing halves, while the two flanges of the flange connection be glued afterwards. The insulating housing described in DE 12 43 762 B is also made by multilayer molding of plastic and has a mechanically strong outer layer and a thin arc-resistant inner layer. In this case, a deletion device is installed. Front openings are through

Power connections for a contact arrangement of the extinguishing device closed.

A circuit breaker for rated voltages of 36 to 84 kV offered by the patent applicant under the name EDI SK typically contains three identical switch poles held on a common mounting frame. Each of the three switch poles has a post insulator, which is connected via an electrically conductive flange with an insulating gas-filled insulating housing. In the insulating housing is provided for switching on and off of a circuit contact arrangement. Driving force for actuating the contact arrangement is brought from outside via a guided in the support insulator insulating rod to the contact arrangement. The enclosed by the insulating housing and the support insulator volumes are interconnected. The thus formed volumes of the three switch poles communicate with each other via a connector housing.

The insulating housings and the post insulators of the switch poles are generally made of porcelain or a fiber reinforced polymer and are prefabricated. In the manufacture of a switch pole, the contact arrangement and a gear comprising the insulating rod are mounted in the insulating housing, in the support insulator and in the connection housing. In these assembly work, numerous points are to be sealed in order to avoid gas losses. If one of the switch poles is defective, the insulating gas must first be removed from all three poles.

PRESENTATION OF THE INVENTION

The invention, as indicated in the claims, the object is to provide a switch pole of the type mentioned, which can be manufactured and maintained inexpensively and yet by a great reliability. At the same time it is also an object of the invention to provide a method by which such a switch pole can be manufactured in large numbers in an economical manner.

When Schalterpol according to the invention, an inner shell of the cup-shaped insulating housing is formed before the infusion of an outer shell as gas-tight sealable vessel. In addition, prior to infusion, the housing accommodates at least the contact arrangement and also has a dimensional stability prior to infusion sufficient to support its own weight and all parts held by it.

As a result, an economical production of the switch pole is made possible. On the one hand, the vessel which receives and carries the active parts of the switch pole, such as the contact arrangement and the power connections, can be prefabricated in large numbers and therefore cost-effectively. On the other hand, the insulator no longer has to be prefabricated, but can now be applied directly to the prefabricated vessel, depending on the requirements of the design of the switch pole. At the same time it is achieved that the functions of the gas-tightness and the mechanical and dielectric strength of the insulating housing are decoupled from each other. The gas-tightness of the insulating housing is achieved regardless of its mechanical strength by the gas-tight and the contact arrangement receiving vessel. The mechanical strength of the insulating housing and at the same time the electrical insulation to the outside is achieved by the vessel embedding and supporting insulator. Elements required in the prior art for sealing the prefabricated insulating housing after assembly of the contact arrangement, a transmission for transmitting driving force to the contact arrangement and a support insulator are no longer needed.

In a particularly suitable for an automatic production of the switch pole method, a first at least the contact arrangement containing, gas-tight sealable vessel prefabricated through the wall at least two power terminals of the contact arrangement and a closable opening for filling of insulating gas are performed, and which has a dimensional stability, the to carry his own weight and all he held Parts is sufficient, then the prefabricated vessel is placed in a mold, and is then poured into the mold on the wall of the vessel, the vessel at least partially embedding insulator.

Advantageous developments of the Schalterpols and the method according to the invention are described below.

BRIEF DESCRIPTION OF THE FIGURES

With reference to drawings, embodiments of the invention will be explained in more detail below. Hereby shows:

1 is a plan view of a guided along an axis section through a first embodiment of a particular for a gas-insulated high-voltage switch switch pole according to the invention,

A casting mold, in which in the manufacture of the switch pole according to Fig.1 a

Insulator is poured onto a vessel of the switch pole, in which a contact arrangement and a gear of the Schalterpols are arranged, and show

Figures 3 to 6 are each a plan view of a guided along an axis section through one of four other embodiments of the switch pole according to the invention.

WAYS FOR CARRYING OUT THE INVENTION

In all figures, like reference numerals refer to like acting parts and repeated reference numerals may be omitted. The five embodiments of the switch pole according to the invention shown in FIGS. 1 and 3 to 6 each have a pressure with an insulating gas, for example based on sulfur hexafluoride, nitrogen, oxygen or carbon dioxide or mixtures of these gases, such as air, with a pressure up to some bar filled and largely tubular shaped insulating housing 1. By the Wall of the housing are two power connections 2, 3 guided for a held in the housing 1 contact arrangement. The contact arrangement has two along an axis 4 relative to each other displaceable switching pieces 5, 6, of which the one, namely 5, is held stationary and is electrically conductively attached to a perpendicular to the axis 4 aligned and electrically connected to the power connector 2 metal plate 7 while the other switching piece, namely 6, is attached to a metal driven member 8 of a transmission 9 and can be moved by the gear 9 along the axis 4. The switching piece 5 need not necessarily be held stationary, it may also be arranged displaceably along the axis 4. Instead of a metal plate 7 may also be another current-conducting part, such as a cup or a carrying star, may be provided. If the switching piece 6 is electrically and / or magnetically driven, then the gearbox 9 can be omitted if necessary.

For reasons of clarity, the two contact pieces 5, 6 are shown only as arcing contacts. In general, the contact arrangement also includes a continuous-current serving, parallel to the arcing contacts switched Nennstromkontaktanordnung and optionally also an insulating and a heating volume and a piston-cylinder compression device for providing pressurized gas, which serves in a switching operation of the blowing of a switching arc.

The switching piece 6 is connected via the serving as a switching piece support output member 8, an output member axially leading Gleitkontaktanordnung 10 and designed as a metallic star or metal plate holder 1 1 to the power connector 3 electrically connected. The gearbox 9 has an insulating rod 12, which is held pivotably on the output member 8, and a shaft 13 which carries at its right-pointing end two unsigned crank arms, to which an end of the insulating rod 12 facing away from the output member 8 is pivotally mounted.

The insulating housing 1 is constructed shell-shaped and has obviously an inner and an outer shell. The inner shell forms the wall of a contact arrangement receiving and filled with the insulating gas-tight closed vessel 20. The outer shell is designed as an insulator 30 and embeds the vessel 20. The vessel 20 is supported against a force caused by the pressure of the insulating gas to the outside. Therefore, it is sufficient that the vessel 20 before embedding in the insulator 30 has a dimensional stability which is sufficient to support its own weight and all parts held by it, for example the contact arrangement. The wall of the vessel 20 is formed predominantly of an electrically insulating material, such as in particular a polymeric or ceramic material, such as PTFE, which material is largely resistant to the action of the arc formed by the corrosive gases and good dielectric properties, such as high dielectric strength and good tracking resistance. This material may be monolithic or layered and also includes composites containing polymers filled with fibers and / or powders.

At locations where the power connections 2, 3 or the output or drive member of the Gethebse 9 are guided into the interior of the vessel 20, the vessel generally made of metal wall parts, which with the wall part formed of insulating material such as by joining or gluing are connected in a gastight manner. The gas-tightness of the vessel 20 can be optimized by a layer of the above-mentioned corrosion-resistant insulating material applied to its inside, in particular to the connecting seams, which can be readily deformed.

Obviously, the vessel 20 contains a closable opening 21, which is arranged in a wall made of metal wall part of the vessel. This opening is used for the inlet or outlet of the insulating gas. In addition, sensors 22 are housed inside the vessel, which detect the state of the insulating gas, in particular its pressure, its temperature, its density, its insulating properties and / or its chemical composition and so during operation of the Schalterpols in a switchgear over a through the Vessel wall guided data line 23 transmitted information to a not shown control and monitoring device of the high voltage switch. In the embodiment of Figure 1, in addition to the contact arrangement, the transmission 9 is held in the vessel 20. The designed as a shaft 13 drive member of the transmission 9 is mounted in a designed as a metal disc 24 section of the vessel wall 20. By means of one or more sealing rings so the shaft 13 can be performed in a simple manner gas-tight through the vessel wall into the vessel interior. As can be seen, the opening 21 in the metal disk 24 is arranged. With an outside of the insulating housing 1 arranged valve 25, the opening 21 can be closed or kept open, so that as required insulating gas or other gas can be introduced into the interior of the vessel 20 or pumped out of the vessel again. In a made of insulating material and running as a vessel bottom 26 section of the wall of the vessel 20, a predetermined breaking point 27 is formed, which breaks above a still permissible internal pressure of the vessel 20, so that then escape the insulating gas via a molded-in insulator 30 outflow channel 31 to the outside can.

The wall of the vessel 20 is formed in the embodiment of Figure 1 of the circular metal plate 7, two formed as a hollow cylinder and made of insulating material housing portions 29, 29 ', also made of insulating material bottom 26 and the metal disc 24. By inserting the transmission 9 in the hollow cylinder 29 ', gas-tight connection of the two hollow cylinders 29, 29' on the bracket 1 1, attaching the contact piece 6 on the output member 8 of the transmission 9, attaching the contact piece 5 to the metal plate 7 and subsequent gas-tight insertion of the contact piece 5 supporting metal plate 7 and the sensor 22 holding the bottom 26 so the vessel 20 can be made in a simple manner.

Alternatively, the vessel 20 instead of the two hollow cylinders 29, 29 ', the bottom 26, the metal plate 7 and the holder 1 1 also consist of two along the axis 4 extending shells of insulating material, each half the two end faces and the lateral surface comprise the largely hollow cylindrical vessel and in each half openings for receiving the

Current feedthroughs 2 and 3 and the metal disc 24 are formed. After inserting the contact arrangement, the transmission 9 and the sensors 22, the two half-shells can be approximately by joining, welding and / or bonding are joined together to form the vessel 20. To increase the gas-tightness, the vessel 20 is lined with an elastically easily deformable liner of an insulating material, which material, such as PTFE, is resistant to the arc generated by the arc-generating aggressive gases.

The vessel 20 produced in this way has a mechanical strength which makes it possible to enclose it as a self-contained unit in a two-part casting mold 40 apparent from FIG. The mold 40 has two separable, pressure and / or vacuum-tight lockable half-shells 41, 42 and a non-designated passage opening for the metal plate 24. The interior of the vessel 20 can so on the

Vessel opening 21 and the valve 25 are connected to a located outside the mold 40 gas supply system 43. In addition, the mold 40 has two further openings, not shown. Air can escape from the mold through one of these openings, and liquid casting compound, typically filled or unfilled casting resin, in particular based on epoxy, can be passed through the mold into the mold 40.

After introducing the prefabricated vessel 20 into the mold 40, the two half-shells 41, 42 are closed and the mold is evacuated via one of the two openings, not shown. To relieve the vessel 20, this can be evacuated via the opening 21 at the same time. Subsequently, the mold is filled with potting compound under vacuum over the second of the two openings, not shown. The filled under vacuum mass is then cured at elevated temperature to form the vessel 20 embedding and supporting insulator 30. Occurring pressure increases in the mold 40 can be compensated by appropriate pressure increases generated by the gas supply system 43 in the vessel interior, so that the wall of the vessel is kept practically free of force during the casting.

Alternatively, potting compound can be pressed under pressure into the mold 40. The air may escape through the second opening in such an automatic pressure gelling process. Also in this casting process can be achieved by synchronous pressure control of the interior of the vessel 20 that the wall of the vessel 20 during the casting free from unwanted forces. In contrast to casting under vacuum, the production times of the switch pole can be considerably shortened during automatic pressure gelling. If the mechanical strength of the vessel is sufficiently high, then the casting process can also be carried out if the insulating gas has already been introduced into the vessel 20 and the vessel is already closed.

After demolding the casting body, filling the vessel 20 with the gas supplied from the gas supply 43 insulating gas and closing the opening 21 of the switch pole is then completed. The outer surface of the insulator 30 may subsequently be provided with one or more layers of another insulating material so as to enable the properties of the insulator for particular applications. If the switch pole is to be used outdoors, it is advisable to provide a silicone coating.

In the embodiment of the inventive Schalterpols according to Figure 3, in contrast to the embodiment of Figure 1, the bottom and adjoining wall parts of the vessel 20 designed as a metal cup 28 and is now the shaft 13 rotatably supporting metal disk 24 in the wall 28 'of Metal cup 28. Instead of a predetermined breaking point formed in the bottom, an opening is provided in the bottom 28 "of the metal cup which limits overpressure created by a pressure relief valve 27 'in the vessel 20. This embodiment is intended for interior applications, but can be used during training of the insulator 30 according to the embodiment of Fig. 1 is also used for outdoor applications Since the metal cup 28 already has a high mechanical strength, it is generally sufficient if the insulator 30 is only guided to the wall 28 'of this cup and its bottom 28 "and at least sections the cup wall 28 'leaves open (not shown in Figure 3).

In the embodiment of Figure 4, the insulator closes next to the vessel 20 and the gear 9 receiving, air-filled space 32 and is the longitudinal axis 4 and movable as a carrier of the movable contact piece 6 serving output member 8 of the transmission 9 gas-tight through the wall of the vessel 20 out. The bottom of the vessel 20 is now used as a metal plate formed bracket 1 1 formed. In the metal plate 11, the filling opening 21 is formed, which can be easily opened or closed by means of arranged in the easily accessible space 32 valve 25 in the manufacture of the Schalterpols or during maintenance. One of two further openings in the metal plate 1 1 serves to receive the pressure relief valve 27 ', whereas arranged in the second opening of the sliding contact 10 and the driven member 8 is guided. The second opening is closed gas-tight by a arranged in the interior of the vessel 20, at the edge of the opening and on the lateral surface of the output member 8 held expansion body 14, such as a bellows made of corrosion-resistant material. The volume of the vessel 20 can be kept so small. This also applies to the embodiments of the switch pole according to FIGS. 5 and 6.

In contrast to the embodiment according to FIG. 4, in the embodiment according to FIG. 5 the insulating housing 1 is held on a support insulator 50 comprising the gear 9, which can be produced independently of the housing 1 and connected to the housing 1 by means of a flange connection 51. Also in this embodiment, it can be seen that along the axis 4 displaceable and serving as a carrier of the movable contact piece output member 8 of the transmission 9 gas-tight through the serving as the bottom of the vessel 20 metal plate 1 1. 4, since the support insulator 50 is not integrated with the insulator 30 but is manufactured and assembled independently thereof, the mold used in embedding the vessel 20 in the insulator 30 can be made small. This is of particular advantage when the insulator 30 is manufactured by automatic pressure gelation.

In the embodiment of Figure 6, the transmission 9 in addition to the shaft 13 and a shaft 15. The shaft 15 is guided gas-tight from the air-filled space 32 through the vessel wall into the interior of the vessel 20. The shaft 15 includes an outside and a disposed within the vessel 20, not shown for reasons of clarity crank arm. The arranged outside the vessel crank arm is rotatably connected to the side facing away from the shaft 13 end of the insulating rod 12, whereas arranged in the housing 20 crank arm rotatably connected to one end of a coupling rod sixteenth is connected, the other end is rotatably connected to the now fully disposed in the interior of the vessel 20 driven member 8. The shaft 15 is rotatably mounted in the axially parallel wall of a molded as a depression in the current-conducting holder 1 1 metal cup 17. The current is passed over the now attached to (not designated) metal approaches the holder 1 1 sliding contact 10 and the bracket 1 1 to the power connector 3. In contrast to the embodiments according to FIGS. 4 and 5, a rotary feedthrough, which is generally easier to carry gas-tightly through the wall of the vessel 20 and formed by the shaft 15, takes the place of a sliding leadthrough.

LIST OF REFERENCE NUMBERS

1 insulating housing

2, 3 power connections

4 axis 5, 6 switching pieces

7 metal plate

8 output member

9 gears

10 sliding contact 11 bracket

12 insulating bar

13 wave

14 expansion bodies

15 shaft 16 coupling rod

17 metal cups

20 vessels

21 opening

22 sensors 23 data line

24 metal disc

25 valve

26 vessel bottom 26 'wall 27 predetermined breaking point

27 'overpressure valve

28 metal cups

28 'cup wall

28 "cup bottom 29, 29 'hollow cylinder

30 insulator

31 outflow channel

32 room

40 mold 41, 42 half-shells

43 Gas supply device

50 support insulator

51 flange connection

Claims

1. pole of a high-voltage switch with a insulating gas filled with insulating (1), two through the wall of the insulating housing (1) out power connections (2, 3) and held in an insulating housing and electrically connected to the two power terminals contact arrangement, wherein the Insulating housing (1) is constructed shell-shaped and having an inner and an outer shell, wherein the outer shell is designed as an insulator (30) and poured onto the inner shell and this against a caused by the pressure of the insulating gas

Power supported, characterized in that the inner shell is formed before pouring the outer shell as a gas-tight sealable vessel (20), and that prior to pouring the housing (20) receives at least the contact arrangement and has a dimensional stability, the to wear his own Weight and all parts held by him sufficient.

2. switch pole according to claim 1, characterized in that the vessel (20) has at least two gas-tight interconnected parts, of which at least one is made of insulating material.

3. switch pole according to one of claims 1 or 2, characterized in that in addition to the contact arrangement also guided through the wall of the insulating part of a transmission (9), which force on a in the direction of an axis (4) movable contact piece (6) Contact arrangement transmits, is held in the vessel.

4. switch pole according to claim 3, characterized in that through the wall of the vessel (20) has a shaft (13) of the transmission (9) is guided.

5. switch pole according to claim 4, characterized in that the shaft (13) in a metal disc (24) running portion of the wall of the vessel (20) is rotatably mounted.

6. switch pole according to claim 4, characterized in that a bottom (28 ') of the vessel (20) is part of a metal cup (28), and that the shaft (13) through the wall (28 ") of the metal cup is guided.

7. switch pole according to claim 3, characterized in that the insulator (30) in addition to the vessel (20) and a transmission (9) receiving space

(32) includes, and that along the axis (4) displaceable and serving as a carrier of the movable contact piece (6) output member (8) of the transmission (9) from the space (32) gastight through the vessel wall into the interior of the vessel (20 ) is guided.

8. switch pole according to claim 3, characterized in that the insulator (30) in addition to the vessel (20) also includes a space (32) which receives an insulating rod (12) of the transmission (9), and that the transmission (9) a shaft which is arranged between the insulating rod (12) and along the axis (4) displaceable and serving as a carrier of the movable contact piece (6) driven member (8) and from the space (32) gas-tight through the vessel wall into the interior of the vessel (20) is guided.

9. switch pole according to claim 3, characterized in that the insulating housing (1) on a transmission (9) comprehensive support insulator (50) is held, and that along the axis (4) displaceable and as a carrier of the movable contact piece (6) serving output member (8) of the

Transmission (9) from the support insulator (50) gas-tight through the vessel wall into the interior of the vessel (20) is guided.

10. switch pole according to one of claims 1 to 9, characterized in that the vessel (20) includes a closable opening (21) for filling the insulating gas.

11. Switch pole according to claim 10, characterized in that the opening (21) is arranged in a metal-made part of the vessel wall.

12. switch pole according to one of claims 1 to 1 1, characterized in that in the interior of the vessel (20) sensors (22) are arranged for detecting the state of the insulating gas.

13. A method for producing a pole of a high-voltage switch with an insulating housing filled with insulating gas (1), two through the wall of the insulating housing (1) guided power terminals (2, 3) and held in the insulating housing and electrically connected to the two power terminals contact arrangement, characterized in that first at least the contact arrangement containing, gas-tight sealable vessel (20) is prefabricated, through the wall at least the two power terminals (2, 3) of the contact arrangement and a closable opening (21) are guided for the insulating gas, and which Has dimensional stability, to carry his own

Weight and all parts held by him sufficient that the prefabricated vessel (20) is introduced into a mold (40), and that in the mold (40) on the wall of the vessel (20) an insulator at least partially embedding (30 ) is poured.

14. The method according to claim 13, characterized in that the casting process is carried out under vacuum or under pressure.

15. The method according to claim 14, characterized in that the casting process is carried out as an automatic Druckgelierverfahren.

16. The method according to any one of claims 13 to 15, characterized in that during the casting process, the vessel with compressed gas, in particular the insulating gas is filled.