Vacuum interrupter structure and circuit breaker

Abstract

The utility model discloses a vacuum arc-extinguishing chamber structure and circuit breaker, including insulating sleeve, dynamic conducting rod and static conducting rod, and the both ends of insulating sleeve are connected with first metal cover and second metal cover respectively, and dynamic conducting rod movably is provided in first metal cover, and static conducting rod fixedly is provided in second metal cover, and the movable contact provided on dynamic conducting rod and the static contact provided on static conducting rod enter insulating sleeve respectively, still including the first voltage-sharing ring of being sleeved outside first metal cover, the second voltage-sharing ring of being sleeved outside second metal cover and / or static conducting rod, and the first voltage-sharing ring is electrically connected or electric contact with first metal cover, and the second voltage-sharing ring is electrically connected or electric contact with second metal cover and / or static conducting rod, the utility model discloses voltage-sharing ring and metal cover are in equipotential, effectively shielded the tip of three -phase junction, avoided the problem of surface flashover and partial discharge that this area caused by charge accumulation and interface polarization effect.

Description

Technical Field

[0001] This utility model relates to the field of vacuum circuit breaker technology, and in particular to a vacuum interrupter structure and circuit breaker. Background Technology

[0002] The vacuum interrupter is a core functional component of a circuit breaker. It utilizes a high vacuum environment and a special contact structure to generate and extinguish an electric arc, and is a key component for circuit breakers to achieve circuit breaking and insulation restoration. The circuit breaker provides the working environment and mechanical support through structural integration, and its performance parameters and design need to be matched with the characteristics of the interrupter. The two work together to ensure the safe control of the circuit.

[0003] The airtight insulation system of a vacuum interrupter consists of an insulating sleeve, end caps, and a bellows. These components work together to maintain a high vacuum and ensure the sealing of the moving contacts. The ends of the insulating sleeve are welded together to form metal caps. This welding process may result in numerous burrs on the ends of the insulating sleeve, leading to poor surface quality. During normal operation and pressurization of the circuit breaker, these burrs can easily trigger point discharges, thereby compromising the insulation performance of the circuit breaker.

[0004] Furthermore, the three-phase interface area formed by the welded metal cap, insulating sleeve, and outer insulating medium may experience insulation degradation due to uncontrollable factors such as structural design and manufacturing defects. This can lead to field strength concentration, charge accumulation, and interface polarization effects, thereby triggering surface flashover and partial discharge. Utility Model Content

[0005] This utility model addresses the technical problems existing in the prior art by providing a vacuum interrupter structure and circuit breaker.

[0006] The technical solution adopted by this utility model to solve its technical problem is as follows: a vacuum interrupter structure, including an insulating sleeve, a moving conductive rod and a stationary conductive rod, with a first metal cover and a second metal cover respectively connected to both ends of the insulating sleeve, the moving conductive rod movably passing through the first metal cover, and the stationary conductive rod fixedly passing through the second metal cover, and the moving contact provided on the moving conductive rod and the stationary contact provided on the stationary conductive rod respectively entering the insulating sleeve; it also includes a first equalizing ring fitted outside the first metal cover, and a second equalizing ring fitted outside the second metal cover and / or the stationary conductive rod, the first equalizing ring being electrically connected or in contact with the first metal cover, and the second equalizing ring being electrically connected or in contact with the second metal cover and / or the stationary conductive rod.

[0007] In a preferred embodiment, an insulating coating layer is further included, which covers the outer surfaces of the insulating sleeve, the first metal cap, the second metal cap, the first equalizing ring, and the second equalizing ring.

[0008] In a preferred embodiment, the insulating coating layer forms a first umbrella skirt and a second umbrella skirt at its two ends, respectively, with the first umbrella skirt surrounding the first equalizing ring and the second umbrella skirt surrounding the second equalizing ring.

[0009] In a preferred embodiment, the insulating sheathing layer forms a third umbrella skirt at the middle of the outer surface of the menopausal sleeve.

[0010] In a preferred embodiment, the second equalizing ring is located within the insulating coating layer, and the second equalizing ring is provided with one or more through holes, the through holes extending along the axial direction of the second equalizing ring, so that the adhesive liquid can flow through the through holes during the coating process of the insulating coating layer.

[0011] In a preferred embodiment, the first equalizing ring and the first metal cover are electrically connected by an interference fit and / or conductive adhesive; the first equalizing ring includes a first main ring body and a first annular boss extending integrally along the inner periphery of the first main ring body, the first annular boss being sleeved on the outside of the first metal cover.

[0012] In a preferred embodiment, the second equalizing ring and the second metal cap or static conductive rod are electrically connected by an interference fit and / or conductive adhesive; the second equalizing ring includes a second main ring body and a second annular boss integrally extending along the inner periphery of the second main ring body, and the through hole is provided in the second annular boss.

[0013] In a preferred embodiment, the outer contour of the cross-section of the first equalizing ring facing outward is a first continuous arc; the outer contour of the cross-section of the second equalizing ring facing outward is a second continuous arc.

[0014] In a preferred embodiment, both the first equalizing ring and the second equalizing ring are made of conductive metal; the outer diameter of the first equalizing ring is larger than the maximum diameter of the first metal cap; and the outer diameter of the second equalizing ring is larger than the maximum diameter of the second metal cap.

[0015] In a preferred embodiment, the insulating sleeve is provided with an intermediate shield, a moving end shield, and a stationary end shield. The intermediate shield is located around the moving contact and the stationary contact. The moving end shield is located around the moving conductive rod and is integrally formed or electrically connected to the first metal cover. The stationary end shield is located around the stationary conductive rod and is integrally formed or electrically connected to the second metal cover. The sleeve also includes a corrugated tube, which is sleeved around the moving conductive rod and located between the first metal cover and the moving end shield.

[0016] This utility model also provides a circuit breaker, including a housing, wherein the housing is provided with a vacuum interrupter structure as described in this utility model above.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. This utility model also includes a first equalizing ring fitted outside the first metal cover, and a second equalizing ring fitted outside the second metal cover and / or the static conductive rod. The first equalizing ring is electrically connected to the first metal cover, and the second equalizing ring is also electrically connected to the second metal cover and / or the static conductive rod. This ensures that the equalizing ring and the metal cover are at the same potential, effectively shielding the tip of the three-phase interface and avoiding surface flashover and partial discharge problems caused by charge accumulation and interface polarization effects in this area. In addition, the equalizing ring also improves the edge of the electrode, guiding the concentrated electric field to the equalizing ring, thereby improving the overall insulation strength and effectively preventing tip discharge.

[0019] 2. As a preferred embodiment, the present invention further includes an insulating coating layer, which covers the outer surfaces of the insulating sleeve, the first metal cover, the second metal cover, the first equalizing ring, and the second equalizing ring. This enables the present invention to achieve composite insulation and significantly improve the overall insulation performance.

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments; however, the vacuum interrupter structure and circuit breaker of the present invention are not limited to the embodiments. Attached Figure Description

[0021] Figure 1 This is a cross-sectional view of the vacuum interrupter structure of this utility model;

[0022] Figure 2 This is a three-dimensional structural schematic diagram of the first equalizing ring of this utility model;

[0023] Figure 3 This is a top view of the first equalizing ring of this utility model;

[0024] Figure 4 yes Figure 3 AA section view;

[0025] Figure 5 This is a three-dimensional structural schematic diagram of the second equalizing ring of this utility model;

[0026] Figure 6 This is a top view of the second equalizing ring of this utility model;

[0027] Figure 7 yes Figure 6 BB section view;

[0028] Figure 8 This is a sectional view (showing a part) of the circuit breaker of this utility model;

[0029] In the figure, 1. Insulating sleeve; 2. Moving conductive rod; 21. Moving contact; 3. Stationary conductive rod; 31. Stationary contact; 4. First metal cover; 5. Second metal cover; 6. First equalizing ring; 61. First main ring body; 611. First continuous arc; 62. First annular boss; 7. Second equalizing ring; 71. Second main ring body; 711. Second continuous arc; 72. Second annular boss; 721. Through hole; 8. Insulating coating layer; 81. First umbrella skirt; 82. Second umbrella skirt; 83. Third umbrella skirt; 9. Moving end shield; 10. Intermediate shield; 20. Stationary end shield; 30. Bellows; 40. Housing. Detailed Implementation

[0030] In this invention, the terms "first," "second," etc., are used only to distinguish similar objects, not to describe a specific order or sequence, nor should they be construed as indicating or implying relative importance. Furthermore, in the description of this invention, unless otherwise stated, "multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0031] Please see Figures 1-7 As shown, the present invention discloses a vacuum interrupter structure, comprising an insulating sleeve 1, a movable conductive rod 2, and a stationary conductive rod 3. A first metal cover 4 and a second metal cover 5 are respectively connected to both ends of the insulating sleeve 1. The movable conductive rod 2 is movably inserted through the first metal cover 4, and the stationary conductive rod 3 is fixedly inserted through the second metal cover 5. A movable contact 21 on the movable conductive rod 2 and a stationary contact 31 on the stationary conductive rod 3 respectively enter the insulating sleeve 1 and cooperate with each other. The present invention also includes a first equalizing ring 6 fitted outside the first metal cover 4, and a second equalizing ring 7 fitted outside the second metal cover 5 and / or the stationary conductive rod 3. Both the first equalizing ring 6 and the second equalizing ring 7 are made of conductive metal. The first equalizing ring 6 is electrically connected or in contact with the first metal cover 4, and the second equalizing ring 7 is electrically connected or in contact with the second metal cover 5 and / or the stationary conductive rod 3. This ensures that the first equalizing ring 6 and the first metal cover 4, and the second equalizing ring 7 and the second metal cover 5 are at the same potential, effectively shielding the tip of the three-phase junction and avoiding surface flashover and partial discharge problems caused by charge accumulation and interface polarization effect in this area.

[0032] In a preferred embodiment, the present invention further includes an insulating coating layer 8, which covers the outer surfaces of the insulating sleeve 1, the first metal cap 4, the second metal cap 5, the first equalizing ring 6, and the second equalizing ring 7. The insulating coating layer 8 can be made of silicone, rubber, or epoxy resin. This enables the present invention to achieve composite insulation, significantly improving the overall insulation performance.

[0033] Furthermore, the insulating coating layer 8 forms a first umbrella skirt 81 and a second umbrella skirt 82 at its two ends, respectively. The first umbrella skirt 81 surrounds the first equalizing ring 6, and the second umbrella skirt 82 surrounds the second equalizing ring 7. A third umbrella skirt 83 is formed in the middle of the outer surface of the insulating coating layer 8, and the radial dimension of the third umbrella skirt 83 is smaller than the radial dimensions of the first umbrella skirt 81 and the second umbrella skirt 82. The arrangement of these umbrella skirts can greatly improve the creepage distance of this invention.

[0034] The first equalizing ring 6 is exposed outside the insulating coating layer 8 on the side axially away from the insulating sleeve 1, while the second equalizing ring 7 is entirely inside the insulating coating layer 8. The second equalizing ring 7 is provided with one or more through holes 721, which are axially connected to the second equalizing ring 7, so that the adhesive liquid can flow through the through holes 721 during the coating process of the insulating coating layer 8, thereby avoiding the formation of air bubbles and reducing the generation of cavities.

[0035] The molding and assembly processes of the first equalizing ring 6 and the second equalizing ring 7 are simple, facilitating production and installation. In this embodiment, the first equalizing ring 6 is electrically connected to the first metal cover 4 via an interference fit and / or conductive adhesive. Similarly, the second equalizing ring 7 is electrically connected to the second metal cover 5 or the stationary conductive rod 3 via an interference fit and / or conductive adhesive. This method makes the electrical connection between the first equalizing ring 6 and the first metal cover 4, and between the second equalizing ring 7 and the second metal cover 5 or the stationary conductive rod 3, relatively simple and convenient, without incurring additional production costs. Furthermore, this method avoids the need for special thickening of the insulating sleeve 1, thus maintaining the original design dimensions. Therefore, it eliminates the need for new mold costs, material costs, and equipment conversion costs from related suppliers, ultimately effectively reducing production costs.

[0036] like Figures 2-4 As shown, the first equalizing ring 6 includes a first main ring body 61 and a first annular protrusion 62 integrally extending along the inner circumference of the first main ring body 61. The first annular protrusion 62 is fitted over the first metal cover 4, and the two are interference-fitted and can be further coated with conductive adhesive.

[0037] like Figures 5-7As shown, the second equalizing ring 7 includes a second main ring body 71 and a second annular boss 72 integrally extending along the inner circumference of the second main ring body 71. The aforementioned through hole 721 is provided on the second annular boss 72, and preferably there are two through holes 721, which are distributed on opposite sides.

[0038] The outer contour of the first equalizing ring 6 is a first continuous arc 611, which is located on the first main ring body 61. Therefore, the outer contour of the first main ring body 61 is a first arc surface. The outer contour of the second equalizing ring 7 is a second continuous arc 711, which is located on the second main ring body 71. Therefore, the outer contour of the second main ring body 71 is a second arc surface. The arrangement of the first continuous arc 611 and the second continuous arc 711 gives the outer contours of the first equalizing ring 6 and the second equalizing ring 7 smooth surfaces (i.e., the first arc surface and the second arc surface), thereby improving the edge of the electrode. This design directs the concentrated electric field to the first equalizing ring 6 and the second equalizing ring 7, effectively improving the insulation strength and preventing tip discharge. In particular, the first equalizing ring 6 and the second equalizing ring 7 have a large radius of curvature, which further enhances the uniformity of the electric field, reduces the local electric field strength, and thus improves the overall insulation performance.

[0039] The outer diameter of the first equalizing ring 6 is larger than the maximum diameter of the first metal cover 4, and the outer diameter of the second equalizing ring 7 is larger than the maximum diameter of the second metal cover 5. Specifically, in this embodiment, the outer diameter of the first equalizing ring 6 is slightly larger than the maximum diameter of the first metal cover 4 by 1-2 mm. Similarly, the outer diameter of the second equalizing ring 7 is also slightly larger than the maximum diameter of the second metal cover 5 by 1-2 mm.

[0040] The insulating sleeve 1 is made of ceramic and contains an intermediate shield 10, a moving end shield 9, and a stationary end shield 20. The intermediate shield 10 is located around the moving contact 21 and the stationary contact 31. The moving end shield 9 is located around the moving conductive rod 2 and is integrally formed with or electrically connected to the first metal cover 4. The stationary end shield 20 is located around the stationary conductive rod 3 and is integrally formed with or electrically connected to the second metal cover 5. This invention also includes a bellows 30, which is sleeved on the moving conductive rod 2 and located between the first metal cover 4 and the moving end shield 9.

[0041] The arrangement of the moving end shield 9, the intermediate shield 10, and the stationary end shield 20 significantly improves the electric field distribution and enhances the insulation strength. The intermediate shield 10 effectively blocks arc-generated materials, preventing them from affecting the insulating sleeve 1, avoiding a decrease in insulation strength, and promotes the condensation of arc-generated materials on its inner surface, preventing them from returning to the arc gap. This promotes the recovery of the arc gap dielectric strength after arc extinction and improves the breaking capacity. The moving end shield 9 and the stationary end shield 20 shield the internal three-intersection section, uniformize the internal electric field, and prevent the bellows 30 from being burned by arc-generated materials, ensuring its normal operation. This comprehensively improves the reliability and performance of the system.

[0042] This invention discloses a vacuum interrupter structure that effectively shields areas of concentrated electric field by setting external equalizing rings (i.e., a first equalizing ring 6 and a second equalizing ring 7), thereby optimizing the electric field distribution and improving insulation strength. Combined with an external insulating coating layer 8, composite insulation is achieved, further significantly enhancing insulation performance. Specifically, the insulating coating layer 8 employs a skirt structure (including a first skirt 81, a second skirt 82, and / or a third skirt 83), resulting in excellent insulation between the electrodes and the insulating coating side cover. Using finite element simulation software, the surface electric field strength of the insulating coating layer 8 is less than 2.6 kV / mm, effectively avoiding the problem of excessively strong local electric fields and significantly reducing the possibility of creepage and surface flashover.

[0043] This invention further incorporates an internal shielding structure (including a moving-end shielding cover 9, an intermediate shielding cover 10, and a stationary-end shielding cover 20), which, together with the external equalizing rings (a first equalizing ring 6 and a second equalizing ring 7), achieves a comprehensive shielding effect, meeting the requirements for partial discharge and thus possessing excellent insulation performance. When this invention is applied to a tank-type circuit breaker, the insulating medium inside the tank-type circuit breaker is dry air, which, under slightly positive pressure conditions, can meet the insulation level requirements of a 40.5 kV rated voltage switchgear.

[0044] Please see Figure 8 As shown, a circuit breaker of this utility model is specifically a tank-type circuit breaker, which includes a housing 40, which is a grounded metal housing, and a vacuum interrupter structure as described above is provided inside the housing 40.

[0045] For details on the structure and working principle of the vacuum interrupter, please refer to the previous description; it will not be repeated here.

[0046] The present invention relates to a vacuum interrupter structure and circuit breaker. The parts not described herein are the same as or can be implemented using existing technologies.

[0047] The above embodiments are only used to further illustrate a vacuum interrupter structure and circuit breaker of the present invention. However, the present invention is not limited to the embodiments. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A vacuum interrupter structure, comprising an insulating sleeve, a moving conductive rod, and a stationary conductive rod, wherein a first metal cover and a second metal cover are respectively connected to both ends of the insulating sleeve, the moving conductive rod is movably inserted through the first metal cover, and the stationary conductive rod is fixedly inserted through the second metal cover, and a moving contact provided on the moving conductive rod and a stationary contact provided on the stationary conductive rod respectively enter the insulating sleeve; characterized in that: It also includes a first equalizing ring fitted outside the first metal cover and a second equalizing ring fitted outside the second metal cover and / or the static conductive rod. The first equalizing ring is electrically connected or in contact with the first metal cover, and the second equalizing ring is electrically connected or in contact with the second metal cover and / or the static conductive rod.

2. The vacuum interrupter structure according to claim 1, characterized in that: It also includes an insulating coating layer, which covers the outer surfaces of the insulating sleeve, the first metal cap, the second metal cap, the first equalizing ring, and the second equalizing ring.

3. The vacuum interrupter structure according to claim 2, characterized in that: The insulating coating layer forms a first umbrella skirt and a second umbrella skirt at its two ends, respectively. The first umbrella skirt surrounds the first equalizing ring, and the second umbrella skirt surrounds the second equalizing ring. The insulating coating layer forms a third umbrella skirt in the middle of the outer surface of the menopausal sleeve.

4. The vacuum interrupter structure according to claim 2, characterized in that: The second equalizing ring is located within the insulating coating layer, and the second equalizing ring is provided with one or more through holes. The through holes extend along the axial direction of the second equalizing ring, so that the adhesive liquid can flow through the through holes during the coating process.

5. The vacuum interrupter structure according to claim 1, characterized in that: The first equalizing ring and the first metal cover are electrically connected by an interference fit and / or conductive adhesive; the first equalizing ring includes a first main ring body and a first annular boss extending integrally along the inner periphery of the first main ring body, and the first annular boss is sleeved on the outside of the first metal cover.

6. The vacuum interrupter structure according to claim 4, characterized in that: The second equalizing ring is electrically connected to the second metal cover or static conductive rod through an interference fit and / or conductive adhesive; the second equalizing ring includes a second main ring body and a second annular boss that extends integrally along the inner periphery of the second main ring body, and the through hole is provided in the second annular boss.

7. The vacuum interrupter structure according to claim 1, characterized in that: The outer contour of the first equalizing ring is a first continuous arc; the outer contour of the second equalizing ring is a second continuous arc.

8. The vacuum interrupter structure according to claim 1, characterized in that: Both the first equalizing ring and the second equalizing ring are made of conductive metal; the outer diameter of the first equalizing ring is larger than the maximum diameter of the first metal cap; the outer diameter of the second equalizing ring is larger than the maximum diameter of the second metal cap.

9. The vacuum interrupter structure according to claim 1, characterized in that: The insulating sleeve is provided with an intermediate shield, a moving end shield, and a stationary end shield. The intermediate shield is located around the moving contact and the stationary contact. The moving end shield is located around the moving conductive rod and is integrally formed or electrically connected to the first metal cover. The stationary end shield is located around the stationary conductive rod and is integrally formed or electrically connected to the second metal cover. It also includes a corrugated tube, which is sleeved on the moving conductive rod and located between the first metal cover and the moving end shield.

10. A circuit breaker, comprising a housing, characterized in that: The housing is provided with a vacuum interrupter structure as described in any one of claims 1-9.

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