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Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- SIEMENS ENERGY GLOBAL GMBH & CO KG
- Filing Date
- 2023-09-13
- Publication Date
- 2026-05-27
AI Technical Summary
High-voltage circuit breakers face challenges in compact design due to the need for larger distances between conductive housing and insulating components to accommodate lower dielectric strength insulating gases, which are environmentally friendly alternatives to F-gases.
Incorporating a fixed solid insulator made from high dielectric strength materials, such as silicone or epoxy resin, between the interrupt unit and the housing wall of the circuit breaker, allowing for reduced spacing and a more compact design.
This design enables a significant reduction in the size of the circuit breaker while maintaining effective dielectric shielding, even at high voltages, by utilizing the higher dielectric strength of solid insulators compared to traditional insulating gases.
Smart Images
Figure EP2023075113_20032025_PF_FP_ABST
Abstract
Description
[0001] Description
[0002] Circuit breaker
[0003] The invention relates to a circuit breaker with a housing made of an electrically conductive material.
[0004] When such a circuit breaker is in operation, the housing is usually connected to earth potential. To prevent voltage flashovers between the housing and the live components 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 a circuit breaker is often gas-insulated, and the housing of the circuit breaker 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. Therefore, environmentally friendly insulating gases, for example 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 an interrupter unit of the circuit breaker. This has a particularly negative effect on circuit breakers designed for high voltages, as it increases the size of the circuit breaker.The invention is based on the object of specifying a circuit breaker which is improved, in particular with regard to its size, and designed for high voltages, which has a housing which is made of an electrically conductive material.
[0005] The object is achieved according to the invention by a circuit breaker having the features of claim 1.
[0006] Advantageous embodiments of the invention are the subject of the dependent claims.
[0007] A circuit breaker according to the invention comprises
[0008] - a housing made of an electrically conductive material,
[0009] - an interrupter unit arranged in the housing and spaced from a housing wall of the housing by a gap and
[0010] - a solid insulator arranged in the intermediate space, which is made at least predominantly of an electrically insulating insulator material.
[0011] The solid insulator is therefore located between the interrupter unit and the housing wall of the circuit breaker housing. The designation
[0012] Solid insulator comprises that the solid insulator is a solid body under operating conditions of the circuit breaker, i.e. in particular neither a gas nor a liquid. Furthermore, according to the invention the solid insulator is made at least predominantly from an electrically insulating insulating material. Such 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, by arranging a solid insulator between the interrupter unit and the housing wall of the circuit breaker housing, the distance between the interrupter unit and the housing wall 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 the circuit breaker compared to a circuit breaker in which the space between the interrupter unit and the housing wall is only filled with an insulating gas.
[0013] The wording that the circuit breaker comprises a solid insulator with the stated properties does not mean that the circuit breaker has only one such solid insulator. Rather, the circuit breaker can also have several such solid insulators. The wording therefore means that the circuit breaker has at least one such solid insulator. If the circuit breaker has several solid insulators, solid insulators can be arranged, for example, around different areas of an interrupter unit.
[0014] Accordingly, the wording that the circuit breaker comprises an interrupter unit does not mean that the circuit breaker has only one interrupter unit. Rather, the circuit breaker can also have a plurality of interrupter units. The wording therefore means that the circuit breaker has at least one interrupter unit. If the circuit breaker has a plurality of interrupter units, the circuit breaker can, for example, have at least one solid insulator for each of these interrupter units, which is arranged around the interrupter unit. In particular, the circuit breaker can also have a solid insulator that is arranged around all of the interrupter units. In one embodiment of the invention, the housing of the circuit breaker is made from a metallic material. A metallic material is advantageously suitable as a material for an electrically conductive housing.
[0015] In a further embodiment of the invention, the insulating material of the solid insulator is 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.
[0016] In a further embodiment of the invention, electrically conductive additives for field control of an electric field in the housing are embedded in the insulating material of the solid insulator.
[0017] The aforementioned embodiment of the invention takes advantage of the fact that an electric field in the housing of the circuit breaker can be influenced by embedding electrically conductive additives in the insulating material of the solid insulator. In particular, particularly high electric field strengths in regions of the housing can be avoided, for example, by embedding electrically conductive additives in suitable regions of the insulating material in order to homogenise the electric field in the housing. For example, electrically conductive additives are embedded in the insulating material in regions of the solid insulator that border on the interrupter unit and / or in regions of the solid insulator near which an electrical conductor runs in the housing.
[0018] In a further embodiment of the invention, microvaristors are embedded as additives in the insulating material of the solid insulator. A microvaristor is understood here to be a very small varistor with a diameter of, for example, up to 200 pm. A microvaristor is manufactured, for example, from an optionally doped metal oxide, in particular from optionally doped zinc oxide.
[0019] In a further embodiment of the invention, soot particles are embedded as additives in the insulating material of the solid insulator.
[0020] In a further embodiment of the invention, the solid insulator is located on the interrupter unit.
[0021] The above-mentioned embodiment of the invention advantageously enables a dielectric shielding of the interrupter unit from the housing by direct contact of the solid insulator with the interrupter unit.
[0022] In a further embodiment of the invention, the solid insulator is located on the housing wall.
[0023] The above-mentioned embodiment of the invention advantageously enables a dielectric shielding of the interrupter unit from the housing of the circuit breaker by a direct contact of the solid insulator with the housing.
[0024] In a further embodiment of the invention, a portion of the space between the housing wall and the interrupter unit not filled with the solid insulator is filled with an insulating gas. For example, the insulating gas is synthetic air, a fluorinated gas, nitrogen, carbon dioxide, or a mixture of at least two of these gases.
[0025] The above-mentioned embodiment of the invention advantageously enables a dielectric shielding of the interrupter unit from the housing by a combination of the solid insulator with a suitable insulating gas.
[0026] In a further embodiment of the invention, the space between the housing of the circuit breaker and the interrupter unit is completely filled by the solid insulator.
[0027] The aforementioned embodiment of the invention advantageously enables a particularly small distance between the interrupter unit and the housing wall of the circuit breaker housing, since the space between the interrupter unit and the housing wall is completely filled by the solid insulator. As a result, this embodiment of the invention also enables a particularly small size of the circuit breaker.
[0028] In a further embodiment of the invention, at least one electrode is at least partially embedded in the solid insulator for field control of an electric field in the housing.
[0029] The aforementioned embodiment of the invention makes it possible to influence an electric field in the housing of the circuit breaker by at least partially embedding at least one electrode in the insulating material of the solid insulator, so that, for example, particularly high electric field strengths are avoided in regions of the housing. For example, an electrode is at least partially embedded in the insulating material in a region of the solid insulator that borders the interrupter unit or in the vicinity of which an electrical conductor runs in the housing.
[0030] In a further embodiment of the invention, the interrupter unit has a vacuum interrupter. A vacuum interrupter has a switching chamber which is evacuated during operation of the circuit breaker, so that a (technical) vacuum prevails in the switching chamber. Two contact elements are arranged in the switching chamber and can be moved 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. A vacuum interrupter is advantageous, among other things, because a switching arc which occurs between the contact elements when the contact elements are separated has significantly less energy in a vacuum than in a gas due to the lower arc voltage.
[0031] In a further embodiment of the invention, the circuit breaker has at least one electrical conductor embedded in solid insulation, which is electrically connected to the interrupter unit. The solid insulation advantageously electrically shields the electrical conductor from the circuit breaker housing. The solid insulation is made, for example, from a silicone or epoxy resin.
[0032] 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.
[0033] FIG 1 shows a first embodiment of a circuit breaker in a sectional view,
[0034] FIG 2 shows a second embodiment of a circuit breaker in a sectional view,
[0035] FIG. 3 shows a third exemplary embodiment of a circuit breaker in a sectional view. Corresponding parts are provided with the same reference numerals in the figures.
[0036] Figure 1 (FIG. 1) shows a first exemplary embodiment of a circuit breaker 1 in a sectional view. The circuit breaker 1 comprises a housing 3, an interrupter unit 5, and a solid insulator 7.
[0037] The housing 3 comprises a substantially hollow cylindrical body section 9 and two column sections 11, 13 projecting from the body section 9 in the manner of trouser legs. The housing 3 is made of an electrically conductive material, for example a metallic material, and is grounded during operation of the circuit breaker 1, i.e., is at an electrical ground potential during operation of the circuit breaker 1.
[0038] The interrupter unit 5 is arranged in the body section 9 at a distance from a housing wall 15 of the housing 3 by an intermediate space 17. The interrupter unit 5 has two contact elements 19, 21 arranged in a switching chamber 18, which 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. For example, the interrupter unit 5 has a vacuum interrupter, the switching chamber 18 of which is evacuated during operation of the circuit breaker 1, so that a (technical) vacuum prevails therein.
[0039] An electrical conductor 23, 25 is guided through each column section 11, 13 of the housing 3, which electrical conductor is electrically connected to a contact element 19, 21 of the interrupter unit 5 and is fixed in the column section 11, 13 by an insulator 27, 29 made of an electrically insulating material. Each of these electrical conductors 23, 25 extends to an end of the column section 11, 13 facing away from the body section 9 of the housing 3, through which it is guided, and is guided out of the housing 3 at this end through a feedthrough 31, 33.
[0040] The solid insulator 7 is made at least predominantly from an electrically insulating material, for example, from a silicone or epoxy resin. Electrically conductive additives for controlling an electric field in the housing 3 can also be embedded in the insulating material of the solid insulator 7. For example, microvaristors and / or soot particles can be embedded in the insulating material of the solid insulator 7 as additives. The additives are arranged, for example, in regions of the solid insulator 7 in which the solid insulator 7 borders the interrupter unit 5, and / or in regions of the solid insulator 7 near which an electrical conductor 23, 25 runs.
[0041] The solid insulator 7 rests against the interrupter unit 5 at a distance from the housing wall 15. The portion of the gap 17 between the housing wall 15 and the interrupter unit 5 not filled by the solid insulator 7 is filled with an insulating gas during operation of the circuit breaker 1. The insulating gas is, for example, synthetic air, a fluorinated gas (so-called F-gas), nitrogen, carbon dioxide, or a mixture of at least two of these gases.
[0042] Figure 2 (FIG 2) shows a second embodiment of a circuit breaker 1 in a sectional view. This embodiment differs from the embodiment shown in Figure 1 only in that the electrical conductors 23, 25, which are routed through the column sections 11, 13 of the housing 3, are each embedded in a solid insulation 35, 37. As a result, the electrical conductors 23, 25 are dielectrically shielded from the housing 3 by the solid insulation 35, 37. The solid insulation 35, 37 is each made, for example, from a silicone or epoxy resin.
[0043] Figure 3 (FIG. 3) shows a third exemplary embodiment of a circuit breaker 1 in a sectional view. This exemplary embodiment differs from the exemplary embodiment shown in Figure 1 only in that electrodes 39 to 42 are each at least partially embedded in the solid insulator 7 for field control of an electric field in the housing 3. Two electrodes 39, 40 are arranged at each end of the switching chamber 18 of the interrupter unit 5, and two further electrodes 41, 42 are each arranged around one of the electrical conductors 23, 25.
[0044] 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. Circuit breaker (1) comprising - a housing (3) made of an electrically conductive material, - an interrupter unit (5) arranged in the housing (3) and spaced from a housing wall (15) of the housing (3) by an intermediate space (17) and - a spacer arranged in the intermediate space (17) Solid insulator (7) which is made at least predominantly of an electrically insulating insulator material.
2. Circuit breaker (1) according to claim 1, wherein the housing (3) is made of a metallic material.
3. Circuit breaker (1) according to claim 1 or 2, wherein the insulating material is a silicone or epoxy resin.
4. Circuit breaker (1) according to one of the preceding claims, wherein the insulating material of the Solid insulator (7) electrically conductive additives for field control of an electric field are embedded in the housing (3).
5. Circuit breaker (1) according to claim 4, wherein microvaristors are embedded as additives in the insulating material of the solid insulator (7).
6. Circuit breaker (1) according to claim 4 or 5, wherein soot particles are embedded as additives in the insulating material of the solid insulator (7).
7. Circuit breaker (1) according to one of the preceding claims, wherein the solid insulator (7) is adjacent to the interrupter unit (5).
8. Circuit breaker (1) according to one of the preceding claims, wherein the solid insulator (7) rests against the housing wall (15).
9. Circuit breaker (1) according to one of the preceding claims, wherein a part of the intermediate space (17) not filled by the solid insulator (7) is filled with an insulating gas.
10. Circuit breaker (1) according to claim 9, wherein the insulating gas is synthetic air, a fluorinated gas, nitrogen, carbon dioxide or a mixture of at least two of these gases.
11. Circuit breaker (1) according to one of claims 1 to 8, wherein the intermediate space (17) is completely filled by the solid insulator (7).
12. Circuit breaker (1) according to one of the preceding claims, wherein at least one electrode (39, 40, 41, 42) is at least partially embedded in the solid insulator (7) for field control of an electric field in the housing (3).
13. Circuit breaker (1) according to one of the preceding claims, wherein the interrupter unit (5) comprises a vacuum interrupter.
14. Circuit breaker (1) according to one of the preceding claims with at least one Solid insulation (35, 37) embedded electrical conductor (23, 25) which is electrically connected to the interrupter unit (5).