Circuit breaker
By using conductive material housings and solid insulators in high-voltage circuit breakers, combined with conductive additives to control the electric field, the problem of increased circuit breaker size was solved, achieving a compact and efficient circuit breaker design.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-09-13
- Publication Date
- 2026-04-14
AI Technical Summary
Existing high-voltage circuit breakers have increased in size due to the use of environmentally friendly insulating gases, making it difficult to reduce the size of the circuit breaker while maintaining dielectric strength.
A housing made of conductive material is used, and a solid insulator is arranged between the housing and the interrupt unit. The high dielectric strength insulating material is used to reduce the distance between the interrupt unit and the housing wall, while conductive additives are embedded in the insulator to control the electric field distribution.
Significantly reduce the structural size of the circuit breaker while maintaining high dielectric strength and avoiding electric field inhomogeneity, thus achieving a compact circuit breaker design.
Smart Images
Figure CN121866640A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a circuit breaker having a housing made of conductive material. Background Technology
[0002] During operation of this type of circuit breaker, the casing is typically placed at ground potential. To prevent voltage flashover between the circuit breaker casing and the live components, a minimum distance must be maintained between them. This minimum distance depends on the voltage applied between the casing and the live components and increases with increasing voltage. Furthermore, this minimum distance depends on the dielectric properties of the medium used to fill the casing. Such circuit breakers are often implemented as gas-insulated, and the casing is filled with an insulating gas during operation. In the past, so-called F gases, i.e., fluorinated gases, especially sulfur hexafluoride, were frequently used as insulating gases due to their exceptionally high dielectric strength, enabling compact circuit breaker designs. However, F gases, especially sulfur hexafluoride, are potent greenhouse gases and are therefore environmentally unfriendly. Consequently, more environmentally friendly insulating gases, such as synthetic air or nitrogen, are increasingly being used instead. However, because these insulating gases have lower dielectric strength compared to F gases, a greater distance is required between the casing walls and the live components of the circuit breaker's interrupting unit. This has a particularly negative impact when the circuit breaker is designed for high voltage, as it increases the size of the circuit breaker. Summary of the Invention
[0003] The technical problem to be solved by the present invention is to provide a circuit breaker that is particularly improved in terms of its structural dimensions and designed for use in high voltage, the circuit breaker having a housing made of conductive material.
[0004] According to the present invention, the above-mentioned technical problem is solved by a circuit breaker having the features of claim 1.
[0005] Advantageous designs of the present invention are the subject of the dependent claims.
[0006] The circuit breaker according to the present invention comprises:
[0007] - The housing, which is made of conductive material.
[0008] - An interrupt unit, which is arranged in the housing and spaced apart from the housing wall by a gap, and
[0009] - A solid insulator arranged in the gap, the solid insulator being made primarily of an electrically insulating insulating material.
[0010] In other words, a solid insulator is arranged between the interrupting unit of the circuit breaker and the housing wall of the casing. The term "solid insulator" includes the following: under the operating conditions of the circuit breaker, the solid insulator is solid, i.e., specifically neither a gas nor a liquid. Furthermore, according to the invention, the solid insulator is made at least primarily of an electrically insulating insulating material. For example, such a solid insulator can have a significantly higher dielectric strength (also known as breakdown strength) compared to an insulating gas. Therefore, by arranging the solid insulator between the interrupting unit of the circuit breaker and the housing wall of the casing, the distance between the interrupting unit and the housing wall can be greatly reduced compared to a circuit breaker where only the gap between the interrupting unit and the housing wall is filled with an insulating gas. Therefore, compared to a circuit breaker where only the gap between the interrupting unit and the housing wall is filled with an insulating gas, the present invention advantageously enables a significant reduction in the volume of the circuit breaker and thus a reduction in the structural dimensions of the circuit breaker.
[0011] The statement "the circuit breaker includes a solid insulator having the aforementioned characteristics" does not mean that the circuit breaker has only one such solid insulator. On the contrary, a circuit breaker may have multiple such solid insulators. Therefore, this statement implies that the circuit breaker has at least one such solid insulator. When a circuit breaker has multiple solid insulators, the solid insulators may, for example, be arranged around different areas of the interrupting unit.
[0012] Correspondingly, the statement "the circuit breaker includes interruption units" does not mean that the circuit breaker has only one interruption unit. On the contrary, a circuit breaker may also have multiple interruption units. Therefore, this statement implies that the circuit breaker has at least one interruption unit. When a circuit breaker has multiple interruption units, the circuit breaker may, for example, have at least one solid insulator for each of these interruption units, the solid insulator being arranged around the interruption unit. In particular, the circuit breaker may also have solid insulators arranged around all interruption units.
[0013] In one embodiment of the invention, the circuit breaker housing is made of a metallic material. Metallic materials are advantageously suitable as materials for conductive housings.
[0014] In another embodiment of the invention, the insulating material of the solid insulator is silicone resin or epoxy resin. Silicone resin or epoxy resin is suitable as the insulating material of the solid insulator due to its dielectric properties and the advantageous manufacturing process, for example, by injecting silicone resin or epoxy resin into the solid insulator surrounding the interrupting unit.
[0015] In another embodiment of the invention, conductive additives are embedded in the insulating material of a solid insulator for electric field control of the electric field within the housing.
[0016] The aforementioned design of the present invention utilizes the ability to influence the electric field within the circuit breaker housing by embedding conductive attachments into the insulating material of a solid insulator. In particular, by embedding conductive attachments into suitable regions of the insulating material, the electric field within the housing can be made uniform, for example, avoiding exceptionally high electric field strengths in certain areas of the housing. For instance, conductive attachments can be embedded into the insulating material in regions of the solid insulator adjacent to the interrupting unit, and / or in regions of the solid insulator where electrical conductors extend into the housing in their vicinity.
[0017] In another design of the invention, the micro-resistor is embedded as an add-on into the insulating material of the solid insulator.
[0018] Here, a micro-resistor should be understood as, for example, a very small resistor with a diameter up to 200 μm. Micro-resistors are made, for example, of potentially doped metal oxides, particularly potentially doped zinc oxide.
[0019] In another embodiment of the invention, carbon black particles are embedded as an additive into the insulating material of a solid insulator.
[0020] In another design of the present invention, the solid insulator is in close contact with the interruption unit.
[0021] The aforementioned design of the present invention advantageously enables dielectric shielding of the interrupting unit against the housing through direct contact between the solid insulator and the interrupting unit.
[0022] In another design of the present invention, the solid insulator is in close contact with the shell wall.
[0023] The aforementioned design of the present invention advantageously enables dielectric shielding of the interrupting unit by means of direct contact between the solid insulator and the circuit breaker housing.
[0024] In another embodiment of the invention, the portion of the gap between the housing wall and the interruption unit that is not filled with solid insulator is filled with an insulating gas. For example, the insulating gas is synthetic air, a fluorine-containing gas, nitrogen, carbon dioxide, or a mixture of at least two of these gases.
[0025] The aforementioned design of the present invention advantageously enables dielectric shielding of the interruption unit for the housing through a combination of a solid insulator and a suitable insulating gas.
[0026] In another design of the present invention, the gap between the circuit breaker housing and the interruption unit is completely filled with solid insulator.
[0027] The aforementioned design of the present invention advantageously allows for a particularly small distance between the interrupting unit and the housing wall of the circuit breaker, because the gap between the interrupting unit and the housing wall is completely filled by a solid insulator. Consequently, this design of the present invention also allows for a particularly small structural size of the circuit breaker.
[0028] In another embodiment of the invention, at least one electrode is at least partially embedded in a solid insulator for electric field control of the electric field in the housing.
[0029] The aforementioned design of the present invention, by embedding at least one electrode at least partially into the insulating material of a solid insulator, enables the influence of the electric field within the circuit breaker housing, thereby, for example, avoiding particularly high electric field strengths in the housing region. For example, the electrode is embedded at least partially into the insulating material in the region of the solid insulator adjacent to the interrupting unit, and / or in the region where an electrical conductor extends into the housing in its vicinity.
[0030] In another design of the present invention, the interrupt unit has a vacuum switch tube.
[0031] The vacuum switch tube has a switch chamber that is evacuated during circuit breaker operation, thus creating a (technical) vacuum within the switch chamber. Two contact elements are arranged within the switch chamber, movable relative to each other between a first switching position and a second switching position. In the first switching position, the two contact elements are in contact with each other, and in the second switching position, the two contact elements are separated from each other. The vacuum switch tube is particularly advantageous because the switching arc formed between the contact elements upon separation has significantly less energy in a vacuum compared to in a gas due to the lower arc combustion voltage.
[0032] In another embodiment of the invention, the circuit breaker has at least one electrical conductor embedded in solid insulation, which is electrically connected to the interrupting unit. This solid insulation advantageously provides electrical shielding of the conductor against the circuit breaker housing. The solid insulation is made, for example, of silicone or epoxy resin. Attached Figure Description
[0033] The features, characteristics, advantages, and implementations of the present invention described above will become clearer and more readily understood in conjunction with the following detailed description of the embodiments, taken in conjunction with the accompanying drawings. Herein, in the drawings:
[0034] Figure 1 A first embodiment of the circuit breaker is shown in cross-section.
[0035] Figure 2 A second embodiment of the circuit breaker is shown in cross-section.
[0036] Figure 3 A third embodiment of the circuit breaker is shown in cross-section.
[0037] In the accompanying drawings, corresponding parts are given the same reference numerals. Detailed Implementation
[0038] Figure 1 (Appendix) Figure 1 A first embodiment of the circuit breaker 1 is shown in cross-section. The circuit breaker 1 includes a housing 3, an interruption unit 5, and a solid insulator 7.
[0039] The housing 3 includes a main body section 9 that is essentially a hollow cylinder and two cylindrical sections 11 and 13 that extend from the main body section 9 in the form of trouser legs. The housing 3 is made of a conductive material, such as a metallic material, and is grounded when the circuit breaker 1 is in operation, that is, it is at ground potential when the circuit breaker 1 is in operation.
[0040] Interruption unit 5 is arranged in the main body section 9, spaced apart from the housing wall 15 of housing 3 by gap 17. Interruption unit 5 has two contact elements 19, 21 arranged in switch chamber 18, which are movable relative to each other between a first switch position and a second switch position. In the first switch position, contact elements 19, 21 are in close contact with each other, and in the second switch position, contact elements 19, 21 are separated from each other. For example, interruption unit 5 has a vacuum switch tube, and when circuit breaker 1 is running, the switch chamber 18 of the vacuum switch tube is evacuated, thereby creating a (technical) vacuum in switch chamber 18.
[0041] Electrical conductors 23 and 25 are guided through each cylindrical segment 11 and 13 of the housing 3. These conductors 23 and 25 are electrically connected to the contact elements 19 and 21 of the interruption unit 5 and are fixed in the cylindrical segments 11 and 13 by insulators 27 and 29 made of electrically insulating material. Each of these conductors 23 and 25 extends to the end of the cylindrical segment 11 and 13 through which it is guided, away from the main body segment 9 of the housing 3, and is guided out of the housing 3 at this end by insulating sleeves 31 and 33.
[0042] The solid insulator 7 is made primarily of an electrically insulating material, such as silicone or epoxy resin. Furthermore, conductive attachments for controlling the electric field within the housing 3 can be embedded in the insulating material of the solid insulator 7. For example, micro-rheostats and / or carbon black particles can be embedded as attachments in the insulating material of the solid insulator 7. These attachments are arranged, for example, in the region of the solid insulator 7 adjacent to the interruption unit 5, and / or in the region of the solid insulator 7 where electrical conductors 23 and 25 extend accordingly.
[0043] The solid insulator 7 is attached to the interrupting unit 5 in a manner spaced apart from the housing wall 15. During operation of the circuit breaker 1, the portion of the gap 17 between the housing wall 15 and the interrupting unit 5 that is not filled with the solid insulator 7 is filled with an insulating gas. The insulating gas may be, for example, synthetic air, a fluorinated gas (i.e., so-called F gas), nitrogen, carbon dioxide, or a mixture of at least two of these gases.
[0044] Figure 2 (Appendix) Figure 2 A second embodiment of circuit breaker 1 is shown in cross-sectional view. This embodiment is similar to... Figure 1 The only difference in the illustrated embodiment is that the electrical conductors 23 and 25, guided through the cylindrical segments 11 and 13 of the housing 3, are embedded in solid insulations 35 and 37, respectively. Thus, the electrical conductors 23 and 25 are dielectrically shielded from the housing 3 by the solid insulations 35 and 37. The solid insulations 35 and 37 are, for example, made of silicone or epoxy resin.
[0045] Figure 3 (Appendix) Figure 3 A third embodiment of circuit breaker 1 is shown in cross-sectional view. This embodiment is similar to... Figure 1 The only difference in the illustrated embodiment is that electrodes 39 to 42 are at least partially embedded in the solid insulator 7 for electric field control of the electric field in the housing 3. Here, two electrodes 39 and 40 are respectively arranged at the end of the switching chamber 18 of the interrupt unit 5, while the other two electrodes 41 and 42 are respectively arranged around one of the electrical conductors 23 and 25.
[0046] Although the invention has been shown and described in further detail through preferred embodiments, the invention is not limited to the disclosed examples, and those skilled in the art can derive other variations therefrom without departing from the scope of protection of the invention.
Claims
1. A circuit breaker (1), the circuit breaker comprising: - Housing (3), the housing is made of conductive material. - An interruption unit (5), which is arranged in the housing (3) and spaced apart from the housing wall (15) of the housing (3) by a gap (17), and - A solid insulator (7) arranged in the gap (17), the solid insulator being made primarily of an electrically insulating insulating material.
2. The circuit breaker (1) according to claim 1, wherein, The shell (3) is made of metal.
3. The circuit breaker (1) according to claim 1 or 2, wherein, The insulating material is silicone resin or epoxy resin.
4. The circuit breaker (1) according to any one of the preceding claims, wherein, Conductive additives are embedded in the insulating material of the solid insulator (7) for electric field control of the electric field in the housing (3).
5. The circuit breaker (1) according to claim 4, wherein, The micro-rheostat is embedded as an add-on into the insulating material of the solid insulator (7).
6. The circuit breaker (1) according to claim 4 or 5, wherein, Carbon black particles are embedded as an additive into the insulating material of the solid insulator (7).
7. The circuit breaker (1) according to any one of the preceding claims, wherein, The solid insulator (7) is in close contact with the interruption unit (5).
8. The circuit breaker (1) according to any one of the preceding claims, wherein, The solid insulator (7) is in close contact with the shell wall (15).
9. The circuit breaker (1) according to any one of the preceding claims, wherein, The portion of the gap (17) that is not filled with the solid insulator (7) is filled with insulating gas.
10. The circuit breaker (1) according to claim 9, wherein, The insulating gas is synthetic air, fluorine-containing gas, nitrogen, carbon dioxide, or a mixture of at least two of the gases.
11. The circuit breaker (1) according to any one of claims 1 to 8, wherein, The gap (17) is completely filled by the solid insulator (7).
12. The circuit breaker (1) according to any 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 electric field control of the electric field in the housing (3).
13. The circuit breaker (1) according to any one of the preceding claims, wherein, The interrupt unit (5) has a vacuum switch tube.
14. The circuit breaker (1) according to any one of the preceding claims, the circuit breaker having at least one electrical conductor (23, 25) embedded in solid insulation (35, 37) and the electrical conductor being electrically connected to the interrupting unit (5).