Electrical assembly and circuit breaker

Abstract

The invention relates to an electrical assembly (2) for a circuit breaker (1). The assembly (2) comprises: a breaker unit (10) having at least two electrical connections (12 to 15) which are each designed as a plug or a socket of a plug-in connection system (19 to 22); and a solid insulator (11) in which the breaker unit (10) including the electrical connections (12 to 15) is embedded.

Description

[0001] Description

[0002] Electrical assembly and circuit breaker

[0003] The invention relates to an electrical assembly for a circuit breaker and a circuit breaker.

[0004] Circuit breakers come in various designs. For example, a distinction is made between circuit breakers with a dead-tank design and circuit breakers with a live-tank design.

[0005] A dead-tank circuit breaker is a circuit breaker whose interrupter unit is located in a housing made of an electrically conductive material, usually metal. The housing is usually earthed when the circuit breaker is in operation, i.e. the housing is connected to an electrical ground potential. To prevent voltage flashovers between the housing and the live components of an interrupter unit of the circuit breaker, a minimum distance is required between the housing and the live components. This minimum distance depends on the voltage applied between the housing and the live components and increases with this voltage. Furthermore, the minimum distance depends on the dielectric properties of the medium with which the housing is filled.Such circuit breakers are often gas-insulated, and the circuit breaker enclosure is filled with an insulating gas when the circuit breaker is in operation. In the past, a so-called F-gas, i.e. a fluorinated gas, was often used as the insulating gas, in particular sulfur hexafluoride, which has a particularly high dielectric strength and therefore enables a compact design of the circuit breaker. However, F-gases, and in particular sulfur hexafluoride, are strong greenhouse gases and therefore not environmentally friendly. For this reason, environmentally friendly insulating gases, such as synthetic air or nitrogen, are increasingly being used instead of these gases. However, since these insulating gases have a lower dielectric strength than F-gases, they require a greater distance between a housing wall and the live components of the circuit breaker's interrupter unit.This has a particularly negative effect on a circuit breaker designed for high voltages, as it increases the size of the circuit breaker.

[0006] A live-tank circuit breaker is a circuit breaker whose interrupter unit is electrically insulated from earth potential by an insulator. The live terminals of the circuit breaker are generally insulated by the air surrounding the circuit breaker.

[0007] The invention is based on the object of specifying an electrical assembly with an interrupter unit for a circuit breaker, which is suitable for various designs of the circuit breaker, for example both for a circuit breaker in the dead tank design and for a circuit breaker in the live tank design.

[0008] The object is achieved according to the invention by an assembly having the features of claim 1 and a circuit breaker having the features of claim 7.

[0009] Advantageous embodiments of the invention are the subject of the dependent claims.

[0010] An electrical assembly according to the invention for a circuit breaker comprises

[0011] - an interrupter unit with at least two electrical connections, each designed as a plug or a socket of a plug connection, and - a solid insulator in which the interrupter unit including the electrical connections is embedded.

[0012] The term "solid insulator" implies that the solid insulator is a solid body under the operating conditions of the circuit breaker, i.e., in particular, it is neither a gas nor a liquid. Furthermore, it implies that the solid insulator is made at least predominantly of an electrically insulating material.

[0013] The design of the assembly according to the invention with a solid insulator, in which the interrupter unit including the electrical connections is embedded, offers the advantage that a solid insulator can have a significantly higher dielectric strength, which is also referred to as dielectric strength, than, for example, an insulating gas. Therefore, in the case that the interrupter unit is arranged in an electrically conductive housing of the circuit breaker, by embedding the interrupter unit in the solid insulator, for example, a distance between the interrupter unit and the housing wall of the circuit breaker housing can be significantly reduced compared to a circuit breaker in which the space between the interrupter unit and the housing wall is only filled with an insulating gas.Therefore, the invention advantageously makes it possible to significantly reduce the volume and thus the size of such a circuit breaker compared to a circuit breaker in which the space between the interrupter unit and the housing wall is filled with an insulating gas.

[0014] The design of the interrupter unit with at least two electrical connections, each designed as a plug or a socket of a plug connection, allows these connections to be connected mechanically and electrically to electrical conductors in a simple manner. This advantage of an assembly according to the invention exists regardless of whether the assembly is arranged in a housing of the circuit breaker and whether the

[0015] circuit breaker has a housing at all.

[0016] Furthermore, the design of the interrupter unit with at least two electrical connections, each designed as a plug or a socket of a plug connection, enables connections of the interrupter unit not used for electrical connections to be used for purely mechanical connection of the electrical assembly to other components of the circuit breaker, for example to fix the assembly in a housing of the circuit breaker.

[0017] In summary, an electrical assembly according to the invention therefore enables a more compact design of a circuit breaker due to the solid insulation in the case that the circuit breaker has a housing, a simple connection of the interrupter unit to electrical conductors and a simple mechanical fixing of the electrical assembly in a housing of a circuit breaker by electrical connections of the interrupter unit, which are not used for electrical connections but only for mechanical plug connections.

[0018] In one embodiment of an electrical assembly according to the invention, the interrupter unit has a switching chamber and two contact elements arranged in the switching chamber, wherein the contact elements are movable relative to one another between a first switching position in which they rest against one another and a second switching position in which they are separated from one another, and wherein each contact element is electrically connected to an electrical connection of the interrupter unit. This embodiment of an electrical assembly according to the invention enables the contact elements of the interrupter unit to be electrically contacted by electrical connections of the interrupter unit. In a further embodiment of an electrical assembly according to the invention, each electrical connection of the interrupter unit is designed as part of a cable connection assembly.A cable connection assembly is understood here to be an assembly that enables a cable to be connected to an electrical terminal of the breaker unit.

[0019] In a further embodiment of an electrical assembly according to the invention, the solid insulator is made at least predominantly of a silicone or epoxy resin. A silicone or epoxy resin is suitable as the insulating material of the solid insulator due to its dielectric properties and the advantageous production of the solid insulator, for example, by encapsulating the interrupter unit with the silicone or epoxy resin.

[0020] In a further embodiment of an electrical assembly according to the invention, the solid insulator has ribs on its outside, each of which extends in a ring around a longitudinal axis of the solid insulator. This embodiment of an assembly according to the invention advantageously enables the extension of creepage paths through which leakage currents can flow on the outside of the solid insulator. This is particularly advantageous when the electrical assembly according to the invention is used in an outdoor application without a surrounding housing.

[0021] In a further embodiment of an electrical assembly according to the invention, the interrupter unit has a vacuum interrupter.

[0022] A vacuum interrupter has a switching chamber that is evacuated during operation of the circuit breaker, so that a (technical) vacuum prevails in the switching chamber. A vacuum interrupter is advantageous, among other things, because when the contact elements are separated in the switching chamber, no gas discharges can occur between the contact elements, thus reducing so-called switching arcs between the contact elements.

[0023] A circuit breaker according to the invention has an electrical assembly according to the invention.

[0024] The advantages of a circuit breaker according to the invention result from the above-mentioned advantages of an electrical assembly according to the invention.

[0025] In one embodiment of a circuit breaker according to the invention, the circuit breaker has a housing in which the electrical assembly is arranged.

[0026] In a further embodiment of a circuit breaker according to the invention, the housing is made of an electrically conductive material, in particular a metallic material. Alternatively, the housing is made of an electrically insulating material.

[0027] The above-mentioned embodiments of a circuit breaker according to the invention are aimed, in the case of a housing made of an electrically conductive material, at a circuit breaker in dead-tank design or in gas-insulated switchgear and, in the case of a housing made of an electrically insulating material, at a circuit breaker in live-tank design with a housing for the interrupter unit.

[0028] In a further development of the aforementioned embodiments of a circuit breaker according to the invention, the electrical assembly is supported on a housing wall of the housing by a support unit made of an electrically insulating material. For example, the electrical assembly is mechanically connected to the support unit by a plug-in connection, by means of which an electrical connection of the interrupter unit is mechanically connected to the support unit. The aforementioned embodiments of a circuit breaker according to the invention are aimed in particular at the above-mentioned possibility of using connections of the interrupter unit that are not used for electrical connections for mechanically fixing the electrical assembly in the housing of the circuit breaker.

[0029] In a further embodiment of a circuit breaker according to the invention, the circuit breaker has an electrical conductor that is electrically and mechanically connected to an electrical terminal of the interrupter unit by a plug connection. For example, the electrical conductor is embedded in a solid insulation made of an electrically insulating material. Furthermore, the electrical conductor can be arranged within the housing of the circuit breaker, provided the circuit breaker has a housing for the interrupter unit.

[0030] The aforementioned embodiments of a circuit breaker according to the invention are aimed at the electrical and mechanical connection, also already mentioned above, of the interrupter unit to electrical conductors of the circuit breaker via plug-in connections for which the electrical connections of the interrupter unit are used. In this case, it can be provided in particular that a conductor connected to an electrical connection of the interrupter unit is embedded in solid insulation. This can advantageously shield the electrical conductor, for example, from a housing of the circuit breaker, in particular if the housing is made of an electrically conductive material. This can in particular make it possible to reduce the distances between electrical conductors and a housing wall of the housing and thus also the size of the circuit breaker further.The above-described properties, features, and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more readily understood in connection with the following description of exemplary embodiments, which are explained in more detail in conjunction with the drawings.

[0031] FIG 1 shows a first embodiment of a circuit breaker in a sectional view,

[0032] FIG 2 shows a second embodiment of a circuit breaker in a sectional view,

[0033] FIG 3 shows a third embodiment of a circuit breaker in a sectional view,

[0034] FIG 4 shows a fourth embodiment of a circuit breaker in a sectional view.

[0035] Corresponding parts in the figures are provided with the same reference symbols.

[0036] Figure 1 (FIG. 1) shows a first exemplary embodiment of a circuit breaker 1 according to the invention in a sectional view. The circuit breaker 1 comprises an electrical assembly 2 according to the invention, a housing 3, a first support unit 4, and a second support unit 5.

[0037] The housing 3 comprises a substantially hollow cylindrical body section 6 and two column sections 7, 8 projecting from the body section 6 in the manner of trouser legs. The housing 3 is made from an electrically conductive material, for example from a metallic material, and is earthed during operation of the circuit breaker 1, i.e. is at an electrical earth potential during operation of the circuit breaker 1. The support units 4, 5 are arranged on opposite sides of the housing 3, each on the inside, on a housing wall 9 of the housing 3 and are each made from an electrically insulating material.

[0038] The electrical assembly 2 comprises an interrupter unit 10, a solid insulator 11, and four electrical connections 12 to 15. The interrupter unit 10, including its electrical connections 12 to 15, is embedded in the solid insulator 11.

[0039] The interrupter unit 10 has a switching chamber 16 and two contact elements 17, 18 arranged in the switching chamber 16, wherein the contact elements 17, 18 are movable relative to one another between a first switching position in which they rest against one another and a second switching position in which they are separated from one another. For example, the interrupter unit 10 has a vacuum interrupter whose switching chamber 16 is evacuated during operation of the circuit breaker 1, so that a (technical) vacuum prevails therein. Each contact element 17, 18 of the interrupter unit 10 is electrically connected to two electrical connections 12 to 15 of the interrupter unit 10.

[0040] Each electrical terminal 12 to 15 of the interrupter unit 10 is designed as a plug or a socket of a plug connection and as part of a cable connection assembly. A first terminal 12 and a second terminal 13 are arranged on a first side of the switching chamber 16. The first terminal 12 extends along a longitudinal axis of the interrupter unit 10 towards the first support unit 4. The second terminal 13 extends perpendicular thereto to a first column section 7. The first terminal 12 is mechanically connected to the first support unit 4 by a first plug connection 19.The second terminal 13 is electrically and mechanically connected by a second plug connection 20 to a first electrical conductor 23, which extends through the first column section 7 to an end of the first column section 7 facing away from the body section 6 of the housing 3 and is led out of the housing 3 at this end through a first feedthrough 25. The first electrical conductor 23 is further embedded in a first solid insulation 27.

[0041] A third terminal 14 and a fourth terminal 15 are arranged on a second side of the switching chamber 16 opposite the first side. The third terminal 14 extends along a longitudinal axis of the interrupter unit 10 towards the second support unit 5. The fourth terminal 15 extends perpendicular thereto to the second column section 8. The third terminal 14 is mechanically connected to the second support unit 5 by a third plug connection 21. The fourth terminal 15 is electrically and mechanically connected by a fourth plug connection 22 to a second electrical conductor 24 which extends through the second column section 8 to an end of the second column section 8 facing away from the body section 6 of the housing 3 and is led out of the housing 3 at this end through a second feedthrough 26. The second electrical conductor 24 is further embedded in a second solid insulation 28.

[0042] The solid insulator 11 is made at least predominantly from an electrically insulating insulator material, for example from a silicone or epoxy resin. Electrically conductive additives for field control of an electric field in the housing 3 can also be embedded in the insulator material of the solid insulator 11. For example, microvaristors and / or soot particles can be embedded in the insulator material of the solid insulator 11 as additives. The additives are arranged, for example, in regions of the solid insulator 11 in which the solid insulator 11 borders on the interrupter unit 10, and / or in regions of the solid insulator 11 in the vicinity of which an electrical conductor 23, 24 runs. The solid insulator 11 has ribs 29 on the outside, each of which runs in a ring shape around a longitudinal axis of the solid insulator 11.

[0043] Figure 2 (FIG. 2) shows a second exemplary embodiment of a circuit breaker 1 according to the invention in a sectional view. This exemplary embodiment differs from the exemplary embodiment shown in Figure 1 essentially only in the arrangement of the support units 4, 5 in the housing 3 and the arrangement of the first electrical connection 12 and the third electrical connection 14 of the interrupter unit 10. In this exemplary embodiment, the first support unit 4 is arranged on the housing wall 9 opposite the first column section 7. In this exemplary embodiment, the second support unit 5 is arranged on the housing wall 9 opposite the second column section 8. Accordingly, the first electrical connection 12 and the third electrical connection 14 do not run along the longitudinal axis of the interrupter unit 10, but rather perpendicular to it, to one of the support units 4, 5 in each case.Again, the first terminal 12 is mechanically connected to the first support unit 4 by a plug connection 19 and the third terminal 14 is mechanically connected to the second support unit 5 by a plug connection 21.

[0044] Figure 3 (FIG 3) shows a third exemplary embodiment of a circuit breaker 1 according to the invention in a sectional view. This exemplary embodiment differs from the exemplary embodiment shown in Figure 1 in that the electrical connection 12 and the electrical connection 14 of the interrupter unit 10 are omitted, so that the interrupter unit 10 only has the electrical connections 13 and 15. These are in turn each mechanically and electrically connected to one of the conductors 23 and 24 by a plug connection 20, 22. A further difference from the exemplary embodiment shown in Figure 1 is that the electrical assembly 2 in this case is suspended in the housing 3 by two suspensions 30, 31, each made of an electrically insulating material, the suspensions 30, 31 each being connected to the solid insulator 11 of the assembly 2.

[0045] Figure 4 (FIG 4) shows a fourth embodiment of a circuit breaker 1 according to the invention in a sectional view. In this embodiment, the circuit breaker 1 is designed in the so-called live-tank design, whereby the circuit breaker 1 does not have an electrically conductive housing 3. However, the circuit breaker 1 again has an electrical assembly 2, which is designed as in the embodiment shown in Figure 2. The assembly 2 is not arranged in a housing, but rather on a support 32, for example, for outdoor use of the circuit breaker 1. The electrical connections 12 to 15 are used here to connect the interrupter unit 10 to electrical high-voltage connection lugs 33, 34. Here, too, the connection of a high-voltage connection lug 33, 34 to one of the connections 12 to 15 is a plug connection 20, 21.Because the electrical assembly 2 has four connections 12 to 15, various connection configurations can be realized.

[0046] Although the invention has been illustrated and described in detail by means of preferred embodiments, the invention is not limited by the disclosed examples and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention.

Claims

Patent claims 1. Electrical assembly (2) for a circuit breaker (1), the assembly (2) comprising - an interrupter unit (10) with at least two electrical connections (12 to 15), each designed as a plug or a socket of a plug connection (19 to 22), and - a solid insulator (11) in which the interrupter unit (10) including the electrical connections (12 to 15) is embedded.

2. Electrical assembly (2) according to claim 1, wherein the interrupter unit (10) has a switching chamber (16) and two contact elements (17, 18) arranged in the switching chamber (16), wherein the contact elements (17, 18) are movable relative to one another between a first switching position in which they abut one another and a second switching position in which they are separated from one another, and wherein each contact element (17, 18) is electrically connected to an electrical connection (12 to 15) of the interrupter unit (10).

3. Electrical assembly (2) according to claim 1 or 2, wherein each electrical terminal (12 to 15) of the interrupter unit (10) is formed as part of a cable connection assembly.

4. Electrical assembly (2) according to one of the preceding claims, wherein the solid insulator (11) is made at least predominantly from a silicone or epoxy resin.

5. Electrical assembly (2) according to one of the preceding claims, wherein the solid insulator (11) has ribs (29) on the outside, each of which runs in a ring shape around a longitudinal axis of the solid insulator (11).

6. Electrical assembly (2) according to one of the preceding claims, wherein the interrupter unit (10) comprises a vacuum interrupter.

7. Circuit breaker (1) with an electrical assembly (2) designed according to one of the preceding claims.

8. Circuit breaker (1) according to claim 7 with a housing (3) in which the electrical assembly (2) is arranged.

9. Circuit breaker (1) according to claim 8, wherein the housing (3) is made of an electrically conductive material, in particular of a metallic material.

10. Circuit breaker (1) according to claim 8, wherein the housing (3) is made of an electrically insulating material.

11. Circuit breaker (1) according to one of claims 8 to 10, wherein the electrical assembly (2) is supported on a housing wall (9) of the housing (3) by a support unit (4, 5) made of an electrically insulating material.

12. Circuit breaker (1) according to claim 11, wherein the electrical assembly (2) is mechanically connected to the support unit (4, 5) by a plug connection (19 to 22) by means of which an electrical connection (12 to 15) of the interrupter unit (10) is mechanically connected to the support unit (4, 5).

13. Circuit breaker (1) according to one of claims 7 to 12 with an electrical conductor (23, 24, 33, 34) which is electrically and mechanically connected to an electrical connection (12 to 15) of the interrupter unit (10) by a plug connection (19 to 22).

14. Circuit breaker (1) according to claim 13, wherein the electrical conductor (23, 24) is embedded in a solid insulation (27, 28) made of an electrically insulating material.

15. Circuit breaker (1) according to one of claims 8 to 12 and one of claims 13 or 14, wherein the electrical conductor (23, 24) is arranged within the housing (3).

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