Vacuum interrupter with large diameter coil type contact having a composite support structure and its application

Abstract

This invention discloses a large-diameter coil-type contact with a composite support structure and its application in a vacuum interrupter. The contact includes a stationary contact assembly structure and a moving contact assembly structure. The stationary contact assembly structure includes a stationary conductive rod, a stationary excitation coil fixed to one end of the stationary conductive rod, a stationary composite support structure with a stationary coil support plate and a stationary I-beam support, and a stationary contact plate. The moving contact assembly structure includes a moving conductive rod, a moving excitation coil fixed to one end of the moving conductive rod, a moving composite support structure with a moving coil support plate and a moving I-beam support, and a moving contact plate. The composite support structure includes an I-beam structure with a coil support platform and a contact plate support platform, and multiple coil support plates coated with an insulating layer. The I-beam structure is fixed by positioning protrusions and openings on the coil support plates to enhance the mechanical strength of the excitation coil. This invention significantly enhances the mechanical strength of the contact while meeting the requirements of contact insulation, current carrying, and excitation design.

Description

Technical Field

[0001] This invention belongs to the technical field of high-voltage vacuum circuit breakers, specifically relating to a large-diameter coil-type contact with a composite support structure and its application in a vacuum interrupter. Background Technology

[0002] Against the backdrop of global energy structure transformation and power system upgrading, the large-scale advancement of ultra-high voltage (UHV) transmission and inter-regional grid interconnection projects has placed unprecedentedly high demands on the transmission capacity, reliability, and safety of power equipment. Vacuum circuit breakers, as core equipment in power systems for circuit switching and fault protection, have become the mainstream choice in the medium and low voltage field due to their outstanding advantages such as being oil-free, SF6-free (no SF6 greenhouse gas emissions), having excellent arc-extinguishing performance, long maintenance cycles, and low costs. In recent years, they have been rapidly advancing towards high-voltage and ultra-high-voltage transmission levels of 126kV and above, gradually meeting the needs of large power grids for high-voltage, high-capacity power transmission.

[0003] However, with the significant increase in the voltage level of vacuum circuit breakers, their overall design and core components need to cope with more complex operating conditions. On the one hand, to meet the insulation performance and breaking capacity requirements under high voltage levels, the size of the moving parts of the vacuum circuit breaker needs to be increased accordingly, resulting in a significant increase in moving mass. On the other hand, to shorten the arcing time and improve fault breaking reliability, the opening and closing speed of the circuit breaker must be further improved, especially in 126kV and higher voltage level products, where the speed index is significantly improved compared to medium and low voltage products. With the increase in the moving mass and opening and closing speed of the vacuum circuit breaker, the moment of inertia of the vacuum circuit breaker contacts during the closing collision and opening acceleration process increases significantly during the closing process, causing significant deformation of the contacts. In particular, large-diameter coil contacts are mostly made of pure copper or copper alloys. Although these materials have excellent conductivity and magnetic permeability and can meet the current carrying and excitation requirements of the contacts, their mechanical strength is relatively limited and they cannot withstand the huge impact force under high voltage levels.

[0004] In actual operation, severe impacts can easily lead to problems such as coil structural deformation and damage to the coil slotted structure in traditional coil longitudinal magnetic contacts. This structural damage not only disrupts the uniformity of the longitudinal magnetic field distribution in the contacts, reducing arc extinguishing efficiency, but also increases contact resistance, causing localized overheating and ultimately shortening the contact's service life. Against this backdrop, how to significantly improve the mechanical strength of the coil longitudinal magnetic contacts while ensuring their insulation, current-carrying, and excitation performance has become a key technical bottleneck restricting the development of high-voltage vacuum circuit breakers. Summary of the Invention

[0005] To address the technical challenges in the existing technologies, this invention aims to propose a large-diameter coil contact with a composite support structure and its application in a vacuum interrupter. Based on the structural characteristics of large-diameter coil longitudinal magnetic contacts for high-voltage vacuum circuit breakers, and considering the mechanism by which longitudinal magnetic contacts generate a longitudinal magnetic field, this invention effectively solves the contact collision deformation problem at high voltage levels through innovative structural design, while ensuring the electrical performance of the contacts. This provides technical support for the reliable application of vacuum circuit breakers in higher power transmission levels.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A large-diameter coil-type contact with a composite support structure includes a stationary contact assembly structure 201 and a moving contact assembly structure 202; used in a high-voltage vacuum interrupter.

[0008] The stationary contact assembly structure 201 includes a stationary conductive rod 101, a stationary excitation coil 102, a stationary composite support structure 103, and a stationary contact piece 104; the stationary conductive rod 101 is fixed to the bottom of the stationary excitation coil 102, the stationary contact piece 104 is fixed to the top of the stationary excitation coil 102, and the stationary composite support structure 103 is disposed between the stationary excitation coil 102 and the stationary contact piece 104;

[0009] The stationary end composite support structure 103 includes an I-beam structure 302 and multiple coil support plates 301; the I-beam structure 302 includes a contact plate support platform 401 with a protrusion on the end face near the contact plate and a coil support platform 404 with a protrusion on the end face near the coil; the diameters of the contact plate support platform 401 and the coil support platform 404 are both smaller than the diameters of the two corresponding end faces of the I-beam structure 302;

[0010] The upper annular plane 402 of the contact support platform 401 on the outside of the contact piece support platform 401 has upper positioning and fixing protrusions 403 distributed coaxially and equidistantly; the lower annular plane 405 of the I-beam structure 302 on the outside of the coil support platform 404 has lower positioning and fixing protrusions 406 distributed coaxially and equidistantly.

[0011] The coil support plate 301 has a fan-shaped structure, and its thickness is consistent with the gap height of the stationary excitation coil 102. The diameter of the outer edge arc of the coil support plate 301 is less than or equal to the outer diameter of the stationary excitation coil 102, and greater than the inner diameter of the stationary excitation coil 102, and also greater than the diameters of the contact plate support platform 401 and the coil support platform 404. The coil support plate 301 has an opening structure 501 that matches the upper positioning and fixing protrusion 403 and the lower positioning and fixing protrusion 406 of the I-beam structure 302.

[0012] In the static end composite support structure 103, multiple coil support pieces 301 are fixed on the upper annular plane 402 outside the contact piece support platform 401 of the I-beam structure 302 by upper positioning and fixing protrusion 403; the multiple coil support pieces 301 are coaxially and equidistantly distributed along the upper annular plane 402.

[0013] In the static end composite support structure 103, multiple coil support pieces 301 are fixed on the lower end annular plane 405 outside the coil support platform 404 of the I-beam structure 302 by a lower end positioning and fixing protrusion 406; the multiple coil support pieces 301 are coaxially and equidistantly distributed along the lower end annular plane 405.

[0014] The moving end contact assembly structure 202 includes a moving end conductive rod 108, a moving end excitation coil 107, a moving end composite support structure 106, and a moving end contact piece 105; the moving end conductive rod 108 is fixed to the bottom of the moving end excitation coil 107, the moving end contact piece 105 is fixed to the top of the moving end excitation coil 107, and the moving end composite support structure 106 is disposed between the moving end excitation coil 107 and the moving end contact piece 105;

[0015] The moving end composite support structure 106 has the same structure as the stationary end composite support structure 103.

[0016] One or both of the upper and lower fan-shaped surfaces of the coil support plate 301 are covered with a high-temperature resistant insulating coating; the insulating layer can isolate the electrical interference between the coil support plate and the excitation coil.

[0017] The outer edge arc of the coil support plate 301 has an angle range of 20° to 120°, and the inner edge arc has an angle range of 20° to 120°. This angle range setting of the coil support plate 301 can be matched with the slotting setting of excitation coils with different numbers of turns and sizes.

[0018] The upper annular plane 402 of the I-beam structure 302 is used to fix a coil support plate 301. The number of upper positioning and fixing protrusions 403 is greater than or equal to 2. The number, shape and position of the upper positioning and fixing protrusions 403 match the number, shape and position of the openings of the coil support plate 301 used for positioning and fixing. The upper positioning and fixing protrusions 403 can tightly connect the coil support plate 301 to the upper annular plane 402, which has excellent mechanical strength and provides good support performance for the excitation coil.

[0019] The lower annular plane 405 of the I-beam structure 302 is used to fix a coil support plate 301. The number of lower positioning and fixing protrusions 406 is greater than or equal to 2. The number, shape and position of the lower positioning and fixing protrusions 406 match the number, shape and position of the openings of the coil support plate 301 used for positioning and fixing. The lower positioning and fixing protrusions 406 can tightly connect the coil support plate 301 to the lower annular plane 405, which has excellent mechanical strength and provides good support performance for the excitation coil.

[0020] The coil support piece 301 is made of stainless steel. Stainless steel has excellent mechanical strength and provides good support for the excitation coil. In addition, the stainless steel material is non-magnetic and has no effect on the excitation performance of the contacts.

[0021] The stationary excitation coil 102 and the moving excitation coil 107 are made of copper. Copper excitation coils have low resistivity, which can effectively reduce current loss and improve the current carrying capacity of the contacts.

[0022] A vacuum interrupter includes a large-diameter coil-type contact with a composite support structure, a vacuum interrupter stationary end cover 121 welded to a stationary end conductive rod 101, a stationary end insulating shell 123 connected to the vacuum interrupter stationary end cover 121, a moving end insulating shell 125 connected to the stationary end insulating shell 123, a vacuum interrupter moving end cover 127 placed on the lower side of the vacuum interrupter and welded to a moving end conductive rod 108, and stationary end shielding cover 122, a central shielding cover 124, and a moving end shielding cover 126 distributed from top to bottom inside the vacuum interrupter.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] 1) Significantly enhanced contact mechanical strength. Considering the function and structure of the large-diameter coil longitudinal magnetic contacts in high-voltage vacuum circuit breakers, a composite support structure with coil support plates is added to the slotted gap of the excitation coil and the gap between the excitation coil and the contact plates through a combined design of coil support plates and I-beam structure. The positioning and fixing protrusions on the I-beam structure further enhance the mechanical strength of the large-diameter coil longitudinal magnetic contacts. This combined structure effectively disperses the impact force during closing collisions, preventing deformation of the contact excitation coil due to insufficient strength, and significantly improving the overall deformation resistance of the contacts, meeting the stringent mechanical strength requirements of high-voltage circuit breakers.

[0025] 2) Ensuring stable electrical performance of the contacts. The upper and lower surfaces of the coil support plate are coated with an insulating layer. This insulating layer isolates the stainless steel coil support plate from electrical interference between the excitation coil and the excitation coil, without affecting the current-carrying path and efficiency of the excitation coil itself, nor disrupting the magnetic field distribution of the excitation coil, thus ensuring stable excitation performance. Simultaneously, the insulating layer prevents the stainless steel components from forming stray circuits with other conductive components, avoiding the risk of partial discharge, ensuring the insulation reliability of the contacts under high-voltage conditions, and achieving compatibility between mechanical reinforcement and electrical performance. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the large-diameter coil-type contact with a composite support structure of the present invention.

[0027] Figure 2(a) is a schematic diagram of the end face of the I-beam structure of the present invention near the contact plate.

[0028] Figure 2(b) is a schematic diagram of the end face of the I-beam structure of the present invention near the coil.

[0029] Figure 3 This is a schematic diagram of the coil support sheet of the present invention.

[0030] Figure 4(a) is a front view of the static end composite support structure of the present invention.

[0031] Figure 4(b) is a schematic diagram of the static end composite support structure of the present invention.

[0032] Figure 5 This is a schematic diagram of the vacuum interrupter chamber with a large-diameter coil-type contact featuring a composite support structure according to the present invention. Detailed Implementation

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] like Figure 1 The diagram shown is a schematic of the large-diameter coil-type contact with a composite support structure according to the present invention.

[0035] The system 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 excitation coil 102, a stationary composite support structure 103, and a stationary contact piece 104. The stationary conductive rod 101 is fixed to the bottom of the stationary excitation coil 102, the stationary contact piece 104 is fixed to the top of the stationary excitation coil 102, and the stationary composite support structure 103 is disposed between the stationary excitation coil 102 and the stationary contact piece 104. The moving contact assembly structure 202 includes a stationary contact assembly structure 201 and a moving contact assembly structure 202. The contact assembly structure 202 includes a moving end conductive rod 108, a moving end excitation coil 107, a moving end composite support structure 106, and a moving end contact piece 105. The moving end conductive rod 108 is fixed to the bottom of the moving end excitation coil 107, the moving end contact piece 105 is fixed to the top of the moving end excitation coil 107, and the moving end composite support structure 106 is disposed between the moving end excitation coil 107 and the moving end contact piece 105. The moving end composite support structure 106 has the same structure as the stationary end composite support structure 103.

[0036] Figures 2(a) and 2(b) show schematic diagrams of the end face of the I-beam structure of the present invention on the side near the contact piece and on the side near the coil. The end face of the I-beam structure 302 on the side near the contact piece has a protruding contact piece support platform 401, and the end face on the side near the coil has a protruding coil support platform 404; the diameters of the contact piece support platform 401 and the coil support platform 404 are both smaller than the diameters of the two corresponding end faces of the I-beam structure 302.

[0037] The upper annular plane 402 of the contact support platform 401 on the outside of the contact piece support platform 401 has upper positioning and fixing protrusions 403 distributed coaxially and equidistantly on the upper annular plane 402; the lower annular plane 405 of the coil support platform 404 on the outside of the coil support platform 404 has lower positioning and fixing protrusions 406 distributed coaxially and equidistantly on the lower annular plane 405.

[0038] like Figure 3 The diagram shows a schematic of the coil support plate of the present invention. The coil support plate 301 has a fan-shaped structure, and its thickness is consistent with the gap height of the stationary excitation coil 102. The diameter of the outer edge arc of the coil support plate 301 is less than or equal to the outer diameter of the stationary excitation coil 102, and greater than the inner diameter of the stationary excitation coil 102, and also greater than the diameters of the contact plate support platform 401 and the coil support platform 404. The coil support plate 301 has an opening structure 501. The opening structure 501 matches the upper positioning and fixing protrusion 403 and the lower positioning and fixing protrusion 406 of the I-beam structure 302.

[0039] The coil support plate 301 has one or both of its upper and lower fan-shaped surfaces covered with a high-temperature resistant insulating coating; the outer edge arc of the coil support plate 301 has an angle range of 20° to 120 degrees, and the inner edge arc has an angle range of 20° to 120 degrees.

[0040] Figures 4(a) and 4(b) show a front view and a schematic diagram of the stationary end composite support structure of the present invention. The stationary end composite support structure 103 includes an I-beam structure 302 and a coil support piece 301.

[0041] In the static end composite support structure 103, multiple coil support plates 301 are fixed on the upper annular plane 402 outside the contact plate support platform 401 of the I-beam structure 302 by upper positioning and fixing protrusion 403; the multiple coil support plates 301 are coaxially and equidistantly distributed along the upper annular plane 402.

[0042] Multiple coil support pieces 301 are fixed on the lower end annular plane 405 of the coil support platform 404 of the I-beam structure 302 in the static end composite support structure 103 by a lower end positioning and fixing protrusion 406; the multiple coil support pieces 301 are coaxially and equidistantly distributed along the lower end annular plane 405.

[0043] like Figure 5 The diagram shows a schematic of a vacuum interrupter with a large-diameter coil-type contact featuring a composite support structure according to the present invention. The vacuum interrupter includes a large-diameter coil-type contact with a composite support structure. A stationary end cover 121 is welded to a stationary end conductive rod 101. A stationary end insulating shell 123 is connected to the stationary end cover 121. A moving end insulating shell 125 is connected to the stationary end insulating shell 123. A moving end cover 127 is placed on the lower side of the vacuum interrupter and welded to the moving end conductive rod 108. From top to bottom, a stationary end shield 122, a central shield 124, and a moving end shield 126 are distributed inside the vacuum interrupter.

[0044] This invention is not limited to the preferred embodiments described above. Those skilled in the art can make modifications and variations to the large-diameter coil-type contact with a composite support 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 large-diameter coil-type contact with a composite support structure, comprising a stationary contact assembly structure (201) and a moving contact assembly structure (202), for use in a high-voltage vacuum interrupter; characterized in that: The stationary contact assembly structure (201) includes a stationary conductive rod (101), a stationary excitation coil (102), a stationary composite support structure (103), and a stationary contact piece (104); the stationary conductive rod (101) is fixed to the bottom of the stationary excitation coil (102), the stationary contact piece (104) is fixed to the top of the stationary excitation coil (102), and the stationary composite support structure (103) is disposed between the stationary excitation coil (102) and the stationary contact piece (104); The stationary end composite support structure (103) includes an I-beam structure (302) and multiple coil support plates (301); the I-beam structure (302) includes a contact plate support platform (401) with a protrusion on the end face near the contact plate and a coil support platform (404) with a protrusion on the end face near the coil; the diameters of the contact plate support platform (401) and the coil support platform (404) are both smaller than the diameters of the two corresponding end faces of the I-beam structure (302); The upper annular plane (402) of the outer side of the contact plate support platform (401) has upper positioning and fixing protrusions (403) distributed coaxially and equidistantly; the lower annular plane (405) of the outer side of the coil support platform (404) has lower positioning and fixing protrusions (406) distributed coaxially and equidistantly. The coil support plate (301) has a fan-shaped structure, and its thickness is consistent with the gap height of the stationary excitation coil (102). The diameter of the outer edge arc of the coil support plate (301) is less than or equal to the outer diameter of the stationary excitation coil (102), and is greater than the inner diameter of the stationary excitation coil (102), and is also greater than the diameter of the contact plate support platform (401) and the coil support platform (404). The coil support plate (301) has an opening structure (501) that matches the upper positioning and fixing protrusion (403) and the lower positioning and fixing protrusion (406) of the I-beam structure (302). Multiple coil support plates (301) are fixed on the upper annular plane (402) outside the contact plate support platform (401) of the I-beam structure (302) by an upper positioning and fixing protrusion (403); the multiple coil support plates (301) are coaxially and equidistantly distributed along the upper annular plane (402); Multiple coil support plates (301) are fixed on the lower end annular plane (405) of the coil support platform (404) of the I-beam structure (302) by a lower end positioning and fixing protrusion (406); the multiple coil support plates (301) are coaxially and equidistantly distributed along the lower end annular plane (405). The moving end contact assembly structure (202) includes a moving end conductive rod (108), a moving end excitation coil (107), a moving end composite support structure (106), and a moving end contact piece (105); the moving end conductive rod (108) is fixed to the bottom of the moving end excitation coil (107), the moving end contact piece (105) is fixed to the top of the moving end excitation coil (107), and the moving end composite support structure (106) is disposed between the moving end excitation coil (107) and the moving end contact piece (105); The moving end composite support structure (106) has the same structure as the stationary end composite support structure (103).

2. A large-diameter coil-type contact with a composite support structure according to claim 1, characterized in that: One or both of the upper and lower sector surfaces of the coil support sheet (301) are covered with a high-temperature resistant insulating coating.

3. A large-diameter coil-type contact with a composite support structure according to claim 1, characterized in that: The outer edge arc of the coil support piece (301) has an angle range of 20° to 120°, and the inner edge arc has an angle range of 20° to 120°.

4. A large-diameter coil-type contact with a composite support structure according to claim 1, characterized in that: The upper annular plane (402) of the I-beam structure (302) is used to fix a coil support plate (301). The number of upper positioning and fixing protrusions (403) is greater than or equal to 2. The number, shape and position of the upper positioning and fixing protrusions (403) match the number, shape and position of the openings of the coil support plate (301) used for positioning and fixing. The number of the lower end annular plane (405) of the I-beam structure (302) used to fix a coil support plate (301) is greater than or equal to 2; the number, shape and position of the lower end positioning and fixing protrusions (406) match the number, shape and position of the openings of the coil support plate (301) used for positioning and fixing.

5. A large-diameter coil-type contact with a composite support structure according to claim 1, characterized in that: The coil support piece (301) is made of stainless steel.

6. A large-diameter coil-type contact with a composite support structure according to claim 1, characterized in that: The static end excitation coil (102) and the dynamic end excitation coil (107) are made of copper.

7. A vacuum interrupter, characterized in that: The vacuum interrupter includes a large-diameter coil-type contact with a composite support structure as described in any one of claims 1-6, a vacuum interrupter stationary end cover plate (121) welded to the stationary end 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 the moving end 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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