Vacuum arc-extinguishing chamber with novel core structure and longitudinal magnetic contact and application thereof

Abstract

The application discloses a longitudinal magnetic contactor with a novel core structure and a vacuum arc-extinguishing chamber using the same, and belongs to the field of high-voltage electrical equipment. The longitudinal magnetic contactor comprises a static end contactor combined structure and a dynamic end contactor combined structure. The static end contactor combined structure comprises a static conductive rod, a static contactor cup seat, a static core structure and a static contactor piece. The dynamic end contactor combined structure comprises a dynamic conductive rod, a dynamic contactor cup seat, a dynamic core structure and a dynamic contactor piece. The static core structure and the dynamic core structure have the same structure form, and comprise a core bottom annular structure and a plurality of T-shaped magnetic conduction structures which are fixed on the upper surface of the core bottom annular structure, coaxial and equidistantly distributed. The T-shaped magnetic conduction structure is composed of an upper plane magnetic conduction structure and a vertically fixed middle support structure. The upper plane magnetic conduction structures are electrically isolated from each other and combined to form an annular structure. The longitudinal magnetic contactor of the application can significantly reduce the core mass while keeping the magnetic field performance, reduce the load in the process of opening and closing, and improve the reliability and mechanical life of the circuit breaker operating mechanism.

Description

Technical Field

[0001] This invention belongs to the technical field of high-current vacuum circuit breakers, specifically relating to a longitudinal magnetic contact with a novel iron core structure and its application in a vacuum interrupter. Background Technology

[0002] With the continuous development of power systems, the application range of vacuum circuit breakers has rapidly expanded from medium and low voltage to high voltage levels. In vacuum circuit breakers with voltage levels of 126kV and above, the short-circuit breaking current level is significantly increased, placing higher demands on the breaking capacity and mechanical performance of the vacuum interrupter. To cope with high-voltage, high-capacity breaking conditions, vacuum circuit breakers often adopt a cup-shaped longitudinal magnetic contact structure. By generating a longitudinal magnetic field between the contacts, the arc is evenly distributed on the contact surface, effectively reducing arc concentration erosion and improving the breaking capacity and contact life of the vacuum circuit breaker.

[0003] In cup-shaped longitudinal magnetic contacts used in high-voltage applications, the contact diameter increases with the rated breaking capacity, and the contact mass also increases significantly. The iron core accounts for a large proportion of the total mass. Excessive contact mass not only increases momentum during opening and closing, leading to a heavier load on the operating mechanism, but also reduces the mechanical life and operational reliability of the circuit breaker. Furthermore, to meet the requirements of magnetic field distribution and excitation design, traditional cup-shaped longitudinal magnetic contacts often employ a large-size, integrally heavy iron core structure. While this structure can generate the required longitudinal magnetic field, it has shortcomings in terms of magnetic path utilization and structural lightweighting, making it difficult to reduce the total contact mass. The excessively heavy iron core not only increases the burden on the circuit breaker's mechanical system but also, to some extent, limits the application of longitudinal magnetic contacts in higher-voltage vacuum circuit breakers.

[0004] Therefore, how to effectively reduce the quality by optimizing the core structure while ensuring the design requirements of the longitudinal magnetic field, insulation performance, current carrying capacity, and arc control capability of the cup-shaped longitudinal magnetic contact has become an urgent problem to be solved in the development of high-voltage vacuum circuit breaker technology. Summary of the Invention

[0005] To address the problems existing in the prior art, and based on extensive prior structural optimization design, magnetic field simulation, and experimental accumulation, the present invention aims to propose a longitudinal magnetic contact with a novel iron core structure and its application in a vacuum interrupter. While ensuring the contact breaking capacity, the invention employs a "T"-shaped magnetic guiding structure and a reasonable slot design to significantly reduce the mass of the iron core while maintaining magnetic field performance. This reduces the total mass of the contacts and its inertial load during opening and closing, thereby effectively reducing the working stress of the operating mechanism and improving the mechanical life and long-term operational reliability of the circuit breaker.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A longitudinal magnetic contact with a novel iron core structure includes a stationary contact assembly structure 201 and a moving contact assembly structure 202. The stationary contact assembly structure 201 includes a stationary conductive rod 101, a stationary contact piece 104, a stationary contact cup seat 102, and a stationary iron core structure 103. The stationary conductive rod 101 is fixed to the bottom of the stationary contact cup seat 102, and the stationary contact piece 104 is fixed to the top of the stationary contact cup seat 102. The stationary iron core structure 103 is located inside the stationary contact cup seat 102 and includes a bottom annular structure 301 and multiple T-shaped magnetic conductive structures 302 fixed on the upper surface of the bottom annular structure 301, coaxially and equidistantly distributed. The number of T-shaped magnetic conductive structures 302 ranges from 4 to 200.

[0007] The moving contact assembly structure 202 includes a moving conductive rod 108, a moving contact piece 105, a moving contact cup seat 107, and a moving iron core structure 106; the moving conductive rod 108 is fixed to the bottom of the moving contact cup seat 107, and the moving contact piece 105 is fixed to the top of the moving contact cup seat 107; the structure of the moving iron core structure 106 is the same as that of the stationary iron core structure 103.

[0008] The T-shaped magnetic conductive structure 302 consists of an upper planar magnetic conductive structure 401 arranged parallel to the bottom annular structure 301 of the iron core and an intermediate support structure 402 fixed perpendicularly to the upper planar magnetic conductive structure 401; the upper planar magnetic conductive structures 401 of multiple T-shaped magnetic conductive structures 302 are placed parallel to each other on the same plane, electrically isolated from each other and combined to form an annular structure, and the distance d between two adjacent upper planar magnetic conductive structures 401 is 0.1-10mm.

[0009] In the stationary contact assembly structure 201 and the moving contact assembly structure 202, the upper planar magnetic conductive structure 401 of some T-shaped magnetic conductive structures 302 is provided with a fixed protrusion structure 303 on the surface facing the stationary contact piece 104 and the moving contact piece 105, respectively. The number of T-shaped magnetic conductive structures 302 with fixed protrusion structures 303 ranges from 3 to 10. The surface of the fixed protrusion structure 303 facing the contact piece is coated with a high-temperature resistant insulating material.

[0010] The bottom annular structure 301 of the iron core has two radial slots 403 between every two adjacent intermediate support structures 402. One radial slot 403 communicates with the inner diameter side of the bottom annular structure 301 of the iron core, and the other radial slot 403 communicates with the outer diameter side of the bottom annular structure 301 of the iron core. The length of the radial slot 403 is less than the width of the bottom annular structure 301 of the iron core. The bottom annular structure 301 of the iron core also has a through slot 404, which extends from the inner diameter side of the bottom annular structure 301 of the iron core to the outer diameter side.

[0011] The bottom annular structure 301 and the T-shaped magnetic guiding structure 302 of the iron core are made of high magnetic permeability iron alloy material.

[0012] A vacuum interrupter includes a longitudinal magnetic contact with a novel iron core structure, a vacuum interrupter stationary end cover plate 121 welded to a stationary conductive rod 101, a stationary end insulating shell 123 connected to the vacuum interrupter stationary end cover plate 121, a moving end insulating shell 125 connected to the stationary end insulating shell 123, a vacuum interrupter moving end cover plate 127 placed on the lower side of the vacuum interrupter and welded to a moving conductive rod 108, and a stationary end shielding cover 122, a central shielding cover 124, and a moving end shielding cover 126 distributed sequentially from top to bottom inside the vacuum interrupter.

[0013] Compared with the prior art, the present invention has the following advantages: 1) Significantly reduced contact mass. By arranging T-shaped magnetic conductive structures on the annular structure at the bottom of the iron core, and adopting a structural form in which the upper planar magnetic conductive structure and the middle support structure are vertically combined, multiple upper planar magnetic conductive structures are placed parallel to each other on the same plane and electrically isolated from each other, forming an efficient and uniform longitudinal magnetic flux path. This design reduces the amount of solid iron core material used and reduces the overall mass of the contacts while maintaining the longitudinal magnetic field strength and balance. This effectively reduces the load on the operating mechanism under high current and high voltage breaking conditions, reduces kinetic energy impact, extends the mechanical life of the circuit breaker, and improves the stability of operation.

[0014] 2) Optimize magnetic flux utilization and electrical insulation performance. The slotted annular structure at the bottom of the core cuts off the circulating current path, reducing eddy current losses, improving the longitudinal magnetic field distribution and response speed, and minimizing the risk of localized heating. On some T-shaped magnetic conductive structures, a range of fixed protrusions are provided on the side facing the stationary contact piece. The surface of these protrusions is coated with a high-temperature resistant insulating material, which helps ensure stable positioning of the contact piece and magnetic conductive components. Simultaneously, it isolates high-temperature electrical interference during the arcing stage, thereby improving the insulation and operational reliability of the vacuum circuit breaker under high-voltage conditions.

[0015] 3) High adaptability and manufacturing efficiency. The spacing d between multiple upper planar magnetic conductive structures ranges from 0.1 to 10 mm, providing adjustable space for magnetic field optimization of different specifications of longitudinal magnetic contacts, facilitating parameter optimization by designers for different voltage levels and breaking capacities. The bottom annular structure and T-shaped magnetic conductive structure of the iron core are made of high-permeability iron alloy material, resulting in faster magnetic response speed and stronger arc driving capability. At the same time, combined with the above-mentioned slotted structure, a lightweight design is achieved, reducing processing difficulty and manufacturing costs, making it easy to promote and apply on a large scale in vacuum interrupters and circuit breakers of medium and high voltage levels. Attached Figure Description

[0016] Figures 1(a), 1(b), 1(c), and 1(d) are respectively the side view, top view, bottom view, and sectional view of the novel iron core structure of the present invention.

[0017] Figure 2 This is a cross-sectional view of the longitudinal magnetic contact with a novel iron core structure according to the present invention.

[0018] Figure 3 This is a cross-sectional view of the longitudinal magnetic contact with a novel iron core structure of the present invention and its application in a vacuum interrupter. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] Figures 1(a), 1(b), 1(c), and 1(d) show the side view, top view, bottom view, and sectional view of the novel core structure of the present invention. The static core structure 103 consists of a bottom annular structure 301 and multiple T-shaped magnetically conductive structures 302. The bottom annular structure 301 is made of a high-permeability iron alloy material and has a slotted structure in the radial direction, including: two radial slots 403 opened between the intermediate support structure 402 of every two T-shaped magnetically conductive structures 302, the length of which is less than the width of the bottom annular structure 301; one radial slot 403 communicates with the inner diameter side of the bottom annular structure 301, and the other communicates with the outer diameter side; a through slot 404 extends radially from the inner diameter side to the outer diameter side of the bottom annular structure 301. This slotted distribution can cut off the circulating current path in the core, reduce eddy current losses, reduce the weight of the core, and improve the distribution of the longitudinal magnetic field.

[0021] As shown in Figures 1(a), 1(b), 1(c), and 1(d), the T-shaped magnetic conductive structures 302 are fixed to the upper surface of the bottom annular structure 301 of the iron core, and are coaxially and equidistantly distributed along the circumference, with a quantity ranging from 4 to 200. The T-shaped magnetic conductive structure 302 consists of two parts: an upper planar magnetic conductive structure 401, placed parallel to the bottom annular structure 301 of the iron core, with multiple upper planar magnetic conductive structures 401 on the same plane; and a middle support structure 402, vertically fixedly connected between the upper planar magnetic conductive structure 401 and the bottom annular structure 301 of the iron core. The distance d between two adjacent upper planar magnetic conductive structures (401) is 0.1-10 mm, and they are electrically isolated from each other, forming a ring structure as a whole. Some of the upper planar magnetic conductive structures 401 of the T-shaped magnetic conductive structures 302 have fixed protrusions 303 on the surface facing the stationary contact piece 104, with a quantity ranging from 3 to 10. The surface of the fixed protrusion structure 303 is coated with a high-temperature resistant insulating material to prevent the core material from being directly exposed to high-temperature plasma during the arc burning stage, while ensuring the stability of the longitudinal magnetic field path.

[0022] The T-shaped magnetic conductor structure 302 reduces the weight of the iron core, improves the mechanical life of the circuit breaker, and enhances the reliability of the operating mechanism. The moving iron core structure 106 has the same structural form as the stationary iron core structure 103, which facilitates manufacturing, assembly, and maintenance.

[0023] like Figure 2 As shown, the longitudinal magnetic contact of the present invention includes a stationary contact assembly structure 201 and a moving contact assembly structure 202, both having the same structural form and being symmetrically arranged. The stationary contact assembly structure 201 consists of a stationary conductive rod 101, a stationary contact piece 104, a stationary contact cup seat 102, and a stationary iron core structure 103; the moving contact assembly structure 202 consists of a moving conductive rod 108, a moving contact piece 105, a moving contact cup seat 107, and a moving iron core structure 106.

[0024] like Figure 3 As shown, in the vacuum interrupter chamber of the present invention with a novel iron core structure and its application, the following components are arranged sequentially from top to bottom: a stationary end cover plate 121 of the vacuum interrupter chamber welded to the stationary conductive rod 101; a stationary end insulating shell 123 connected to the stationary end cover plate 121; a moving end insulating shell 125 connected to the stationary end insulating shell 123; and a moving end cover plate 127 of the vacuum interrupter chamber welded to the moving conductive rod 108. Inside the interrupter chamber, a stationary end shielding cover 122, a central shielding cover 124, and a moving end shielding cover 126 are arranged sequentially from top to bottom. Each shielding cover can effectively block the influence of metal vapor and arc combustion on the insulating components, protecting the stability of the vacuum environment.

[0025] This invention is not limited to the preferred embodiments described above. Those skilled in the art can make modifications and variations to the longitudinal magnetic contact with the novel iron core structure and its application in vacuum interrupters based on the teachings of this invention. All such modifications and variations should fall within the protection scope of this invention.

Claims

1. A longitudinal magnetic contact with a novel iron core structure, comprising a stationary contact assembly structure (201) and a moving contact assembly structure (202), characterized in that: The stationary contact assembly structure (201) includes a stationary conductive rod (101), a stationary contact piece (104), a stationary contact cup seat (102), and a stationary iron core structure (103); the stationary iron core structure (103) is located inside the stationary contact cup seat (102) and includes a bottom annular structure (301) of the iron core and multiple T-shaped magnetic conductive structures (302) fixed on the upper surface of the bottom annular structure (301) of the iron core, coaxially and equidistantly distributed; the stationary conductive rod (101) is fixed to the bottom of the stationary contact cup seat (102), and the stationary contact piece (104) is fixed to the top of the stationary contact cup seat (102); The T-shaped magnetic conductive structure (302) consists of an upper planar magnetic conductive structure (401) arranged parallel to the bottom ring structure (301) of the iron core and an intermediate support structure (402) fixed perpendicularly to the upper planar magnetic conductive structure (401); in the stationary contact assembly structure (201), the upper planar magnetic conductive structures (401) of the multiple T-shaped magnetic conductive structures (302) that are coaxial and equidistantly distributed are placed parallel to each other on the same plane, electrically isolated from each other and combined to form a ring structure; The moving contact assembly structure (202) includes a moving conductive rod (108), a moving contact piece (105), a moving contact cup seat (107), and a moving iron core structure (106); the moving conductive rod (108) is fixed to the bottom of the moving contact cup seat (107), and the moving contact piece (105) is fixed to the top of the moving contact cup seat (107); the moving iron core structure (106) has the same structural form as the stationary iron core structure (103).

2. The longitudinal magnetic contact with a novel iron core structure according to claim 1, characterized in that: The number of T-shaped magnetic conductive structures (302) in the static iron core structure (103) ranges from 4 to 200.

3. The longitudinal magnetic contact with a novel iron core structure according to claim 1, characterized in that: The distance d between two adjacent upper planar magnetic structures (401) in the T-shaped magnetic conductive structure (302) is 0.1-10mm.

4. The longitudinal magnetic contact with a novel iron core structure according to claim 1, characterized in that: The upper planar magnetic structure (401) of the T-shaped magnetic conductive structure (302) in the stationary contact assembly structure (201) and the moving contact assembly structure (202) is provided with a fixed protrusion structure (303) on the surface of the T-shaped magnetic conductive structure (302) facing the stationary contact piece (104) and the moving contact piece (105), respectively; the surface of the fixed protrusion structure (303) facing the contact piece is coated with a high-temperature resistant insulating material; the number of T-shaped magnetic conductive structures (302) with fixed protrusion structures (303) ranges from 3 to 10.

5. The longitudinal magnetic contact with a novel iron core structure according to claim 1, characterized in that: The bottom annular structure (301) of the iron core has two radial slots (403) between every two adjacent intermediate support structures (402); the length of the radial slots (403) is less than the width of the bottom annular structure (301), one slot is connected to the inner diameter side of the bottom annular structure (301), and the other slot is connected to the outer diameter side of the bottom annular structure (301); the bottom annular structure (301) of the iron core also has a through slot (404); the through slot (404) extends from the inner diameter side of the bottom annular structure (301) of the iron core to the outer diameter side.

6. The longitudinal magnetic contact with a novel iron core structure according to claim 1, characterized in that: The bottom annular structure (301) and the T-shaped magnetic conductive structure (302) of the iron core are made of high magnetic permeability iron alloy material.

7. A vacuum interrupter, characterized in that: The vacuum interrupter includes a longitudinal magnetic contact with a novel iron core structure as described in any one of claims 1-6, a vacuum interrupter stationary end cover plate (121) welded to a stationary conductive rod (101), a stationary end insulating shell (123) connected to the vacuum interrupter stationary end cover plate (121), a moving end insulating shell (125) connected to the stationary end insulating shell (123), a vacuum interrupter moving end cover plate (127) placed on the lower side of the vacuum interrupter and welded to a moving conductive rod (108), and a stationary end shield (122), a central shield (124), and a moving end shield (126) distributed from top to bottom inside the vacuum interrupter.

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