High-Voltage Switching Device and Switchgear Comprising a High-Voltage Switching Device and Method for Producing a High-Voltage Switching Device

Abstract

The invention relates to a high-voltage switching device, comprising a vacuum interrupting chamber and a switchgear that comprises a high-voltage switching device. Furthermore, the invention relates to a method for producing a high-voltage switching device having a vacuum interrupting chamber. The high-voltage switching device comprises a housing body 1, in which a vacuum interrupting chamber 2 is provided. The vacuum interrupting chamber 2 comprises an immoveable switching contact element 4 and a switching contact element 5 that can move in the axial direction, the moveable switching contact element 5 extending out of the vacuum interrupting chamber 2 and being connected to an actuator 8, which can move in the axial direction, by means of an insulating body 7. The conductor parts 12, 13, 14 that form the current path are connected to the immoveable switching contact element 4 and the moveable switching contact element 5. In the high-voltage switching device according to the invention, a cavity 22 that is filled with an insulating liquid is made in the housing body 1, the moveable switching contact element 5 extending out of the vacuum interrupting chamber 2 and into the cavity 22, and the actuator 8 in turn extending out of the cavity 22 filled with insulating liquid. The high-voltage switching device is characterised in that a sealing arrangement 10 that seals the actuator 8 with respect to the housing body 1 is provided in the cavity 22 that is filled with insulating liquid. As a result, secure disconnection of the load current and the short-circuit current is achieved together with a relatively short insulation distance. Consequently, the high-voltage switching device can be compact.

Claims

1. High-voltage switching device, comprising a housing body (1), in which a vacuum interrupting chamber (2) is provided that comprises an immoveable switching contact element (4) and a switching contact element (5) that can move in the axial direction, the moveable switching contact element (5) extending out of the vacuum interrupting chamber (2) and being connected to an actuator (8), which can move in the axial direction, by means of an insulating body (7), and conductor parts (12, 13, 14) that form the current path being connected to the immoveable switching contact element (4) and the moveable switching contact element (5), characterised in that a cavity (22) that is filled with insulating liquid is made in the housing body (1), the moveable switching contact element (5) extending out of the vacuum interrupting chamber (2) and into the cavity (22), and in that the actuator (8) extends out of the cavity (22), a sealing arrangement (10) that is arranged in the cavity (22) being provided, which seals the actuator (8) with respect to the housing body (1).

2. High-voltage switching device according to claim 1, characterised in that the sealing arrangement (10) comprises a bellows (11) that is arranged in the cavity (22) and surrounds the actuator (8), one end of the bellows (11) being sealed with respect to the actuator (8) and the other end of the bellows being sealed with respect to the housing body (1).

3. High-voltage switching device according to claim 2, characterised in that the cavity (22) is closed by means of a cover (13) that is sealed with respect to the housing body (1), one end of the bellows (11) being sealed with respect to the cover (13).

4. High-voltage switching device according to any of claims 1 to 3, characterised in that the housing body (1) comprises a plastics body (16) that surrounds the cavity (22) at least in part.

5. High-voltage switching device according to claim 4, characterised in that the plastics body (16) consists of a plurality of plastics elements (16A, 16B, 16C) that are interconnected.

6. High-voltage switching device according to claim 5, characterised in that the plastics body (16) comprises a cylindrical plastics element (16C), which surrounds the sealing arrangement (10) at least in part.

7. High-voltage switching device according to either claim 5 or claim 6, characterised in that the plastics body (16) comprises a first bowl-shaped plastics element (16A) and a second bowl-shaped plastics element (16B), the conductor parts (12, 13, 14) that form the current path comprising a moveable conductor part (12), which is electrically connected to the moveable contact element (5), the moveable conductor part (5) being arranged in the cavity (22) and being surrounded by the first and second plastics element (16A, 16B) at least in part.

8. High-voltage switching device according to any of claims 1 to 7, characterised in that the housing body (1) comprises a casting body (15), which receives the vacuum interrupting chamber (2) and the plastics body (16).

9. High-voltage switching device according to claim 8, characterised in that the plastics body (16) is sealed with respect to the vacuum interrupting chamber (2).

10. High-voltage switching device according to claim 9, characterised in that cutting edges (21) are provided on the plastics body (16), the vacuum interrupting chamber (2) comprising a housing (3) that is surrounded, at least in part, by a material (3A) into which the cutting edges (21) cut.

11. Switchgear comprising a high-voltage switching device according to any of claims 1 to 10.

12. Method for producing a high-voltage switching device, wherein the high-voltage switching device comprises: a housing body (1), in which a vacuum interrupting chamber (2) is provided that comprises an immoveable switching contact element (4) and a switching contact element (5) that can move in the axial direction, wherein the moveable switching contact element (5) extends out of the vacuum interrupting chamber (2) and into a cavity (22) that is filled with an insulating liquid and is surrounded by a plastics body (16), and an actuator (8), which can move in the axial direction and is connected to the moveable contact element (5) by means of an insulating body (7), and a sealing arrangement (10) that is arranged in the cavity (22) and seals the actuator (8), which extends out of the cavity (22),with respect to the housing body (1), comprising the following method steps: providing a casting mould, placing the vacuum interrupting chamber (2) and the plastics body (16) in the casting mould, casting the space (19) between the vacuum interrupting chamber (2) and the plastics body (16) with a casting compound in order to provide a casting body (15) that surrounds the vacuum interrupting chamber and the plastics body and in which a cavity (22) that is surrounded by the plastics body (16), at least in part, is made, inserting the actuator (8) and the insulating body (7) and the sealing arrangement (10) into the cavity, filling the cavity (22) with an insulating liquid, and closing the cavity (22) by means of a cover (13) that is sealed with respect to the casting body (15) or the plastics body (16).

13. Method according to claim 12, characterised in that the plastics body (16) is composed of a plurality of plastics elements (16A, 16B, 16C) that are interconnected.

14. Method according to claim 13, characterised in that the plastics body (16) is composed of two bowl-shaped plastics elements (16A, 16B) and one cylindrical plastics element (16C).

15. Method according to any of claims 1 to 14, characterised in that the casting compound is an epoxy resin.

Description

[0025] One embodiment of the invention will be explained in more detail in the following with reference to the drawings, in which

[0026] FIG. 1 is a partially sectional perspective view of one embodiment of the high-voltage switching device according to the invention, and

[0027] FIG. 2 is an exploded view of individual components of the high-voltage switching device according to the invention.

[0028] FIG. 1 shows the components of the high-voltage switching device that are essential to the invention, whilst FIG. 2 is merely an exploded view of individual components of the switching device. Corresponding parts are provided with the same reference numerals in the drawings.

[0029] The high-voltage switching device comprises a housing body 1, which consists of a plurality of parts or components and has a housing half 1A which is the upper housing half in the normal installation position and a lower housing half 1B. A vacuum interrupting chamber 2 having a cylindrical housing 3, which housing receives an upper, fixed switching contact element 4 and a lower, moveable switching contact element 5, is arranged in the upper housing half 1A. Both switching contact elements 4, 5 comprise disc-shaped contacts 4A, 5A, which are arranged inside the housing 3 of the vacuum interrupting chamber 2. By closing or opening the contacts 4A, 5A, the current path can be closed or disconnected, i.e. the load current and the short-circuit current can be switched.

[0030] A chamber 6 is formed in the lower housing half 1B, which chamber is filled with an insulating liquid. The switching contact element 5 that can be displaced in the axial direction of the vacuum interrupting chamber 2 comprises a shaft 5B, which extends out of the vacuum interrupting chamber and into the chamber 6 filled with insulating liquid. The shaft 5B of the moveable switching contact element 5 is sealed with respect to the housing 3 of the vacuum interrupting chamber 2 in a vacuum-tight manner by means of a sealing arrangement (not shown). The lower end of the shaft 5B is connected, by means of an insulating body 7, to an actuator 8 that extends out of the liquid-filled chamber. By actuating the actuator 8, the moveable switching contact element 5 can be axially displaced such that the contacts 4A, 5A are closed or opened.

[0031] The actuator 8 comprises an upper, hollow-cylindrical portion 8A, which is arranged in the chamber 6, and a lower, pin-shaped portion 8B, which is guided so as to be displaceable in the longitudinal direction in the cylindrical space of the upper portion and extends out of the chamber 6. In this case, the upper end of the lower portion 8B is supported on a compression spring 9 in the cylindrical space of the upper portion 8A. When the lower portion 8B is displaced, the upper portion 8A is also displaced such that the moveable switching contact element 5 is axially displaced. The compression spring 9 is used to dampen the impacts when the actuator 8 is actuated. The actuator 8 is driven by a drive unit (not shown), that displaces the lower portion 8B in the axial direction.

[0032] The actuator 8 is sealed in a liquid-tight manner with respect to the housing body 1 by means of a sealing arrangement 10. The sealing arrangement 10 comprises a bellows 11, which surrounds the upper portion 8A of the actuator 8, the upper end of the bellows 11 being connected to the upper portion 8A of the actuator 8 in a liquid-tight manner. The lower end of the bellows 11 is sealed with respect to the housing body 1 in a liquid-tight manner. The bellows 11 and the actuator 8 are connected to earth potential. The housing body 1 comprises an opening 23 on the bottom thereof, which is closed in a liquid-tight manner by a cover 13.

[0033] In the installation position, the liquid-filled chamber 6 comprises an upper and a lower chamber half 6A, 6B. A moveable conductor part 12, for example a copper band, which is connected to the shaft 5B of the moveable switching contact element 5 is arranged in the upper chamber half 6A. The moveable conductor part 12 is electrically connected to additional conductor parts 13 which form the current path; however, said parts are shown only in part. The fixed switching contact element 4 is also connected to additional conductor parts 14 (only shown in part), which are likewise inserted into the housing body 1 or placed on the housing body.

[0034] The housing body 1 comprises a casting body 15, which surrounds the vacuum interrupting chamber 2 and the liquid-filled chamber 6. The casting body 1A forms the outer shell of the housing body 1. The casting compound can be an epoxy resin.

[0035] In the lower housing half 1B, a plastics body 16 composed of a plurality of plastics elements 16A, 16B, 16C sits in the casting body 15. FIG. 2 is an exploded view of the plastics elements 16A, 16B, 16C.

[0036] The plastics body 16 comprises an upper, bowl-shaped plastics element 16A and a lower, bowl-shaped plastics element 16B in the upper chamber half 6A, which elements surround the moveable conductor part 12, and comprises a cylindrical plastics element 16C in the lower chamber half 6B, which cylindrical plastics element surrounds the bellows 11. The plastics elements 16A, 16B, 16C are designed such that they can be suitably composed. They are sealingly inserted into one another and/or sealingly stuck together or welded to one another. All the plastics elements 16A, 16B, 16C have rounded corners or edges.

[0037] The two plastics elements 16A, 16B in the upper chamber half 6A are made of an electrically conductive plastics material, for example the plastics material can be mixed with conductive carbon. Since these plastics elements 16A, 16B can assume the same potential as the moveable conductor part 12 or other conductor parts in the chamber, the electrical field becomes more homogenous towards the outside.

[0038] The plastics element 16C in the lower chamber half 6B, which element is not made of a conductive plastics material, cannot carry a potential. This plastics element 6C is used to securely insulate live parts in the chamber 6 with respect to the actuator 8 that connected to earth potential. In order to increase the creepage distance, the plastics element 16C comprises ribs 17 on the outside thereof.

[0039] The cover 13 of the housing body 1, which seals the liquid-filled chamber 6, is sealed in a liquid-tight manner with respect to the cylindrical plastics part 16C by means of a sealing ring 18 that is arranged between the cover and the plastics part. The method according to the invention for producing the high-voltage switching device will be described in the following.

[0040] In order to produce the switching device, a casting mould (not shown in the drawings) is used, which is designed so as to correspond to the shape and dimensions of the housing body 1 of the switching device and the shape and dimensions of the vacuum interrupting chamber 2 and of the rest of the components of the switching device. The vacuum interrupting chamber 2 is inserted into the upper half of the casting mould, a space 19 remaining between the wall of the casting mould and the vacuum interrupting chamber 2. The plastics body 16 is inserted into the lower half of the casting mould, a space 20 remaining between the wall of the casting mould and the plastics body 16, too. The spaces 19, 20 between the casting mould and the vacuum interrupting chamber or the plastics body are then cast with a casting compound, for example an epoxy resin. As a result, the casting body 15 comprising the chamber 6 to be filled with insulating liquid is formed.

[0041] The upper plastics element 16A in the upper chamber half 6A comprises cutting edges 21 on the upper edge, which cut into a coating 3A of the housing 3 of the vacuum interrupting chamber 2 such that the casting compound, which has a relatively high viscosity in the liquid state, cannot enter a gap between the metal or ceramic housing 3 of the vacuum interrupting chamber 2 and the plastics element 16 when pressurised.

[0042] Once the casting compound has hardened, the moveable conductor part 12, the actuator 8, the insulating body 7 and the sealing arrangement 10 and, where necessary, additional components of the switching device are inserted into the cavity that is surrounded by the plastics part, and the cavity is filled with the insulating liquid. The cavity is then closed in a liquid-tight manner by fitting the cover 13.