A structure-reinforced longitudinal magnetic contact and a vacuum arc-extinguishing chamber using the same

Abstract

The application discloses a structure-reinforced longitudinal magnetic contact and a vacuum arc-extinguishing chamber using the same, and belongs to the technical field of vacuum arc-extinguishing chambers. The structure-reinforced longitudinal magnetic contact comprises a static contact combined structure and a dynamic contact combined structure. The static contact combined structure comprises a static conductive rod, a static excitation contact seat welded at one end of the static conductive rod, a static stainless steel cup seat with a wing piece and a static contact piece. The dynamic contact combined structure comprises a dynamic conductive rod, a dynamic excitation contact seat welded at one end of the dynamic conductive rod, a dynamic stainless steel cup seat with a wing piece and a dynamic contact piece. The wing piece structure attached to the dynamic and static stainless steel cup seats is matched with the slotted gap of the dynamic and static excitation contact seats, and is installed in the longitudinal magnetic slotted gap to play a supporting role. The surfaces of the dynamic and static stainless steel cup seats and the attached wing pieces are coated with an insulating layer, and the electrical performance of the original contact is not affected. On the basis of meeting the insulation, current flow and excitation design of the contact, the mechanical strength of the contact is greatly reinforced.

Description

Technical Field

[0001] This invention belongs to the technical field of high-voltage vacuum circuit breakers, specifically relating to a structurally reinforced longitudinal magnetic contact 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 dimensions of the moving parts of the vacuum circuit breaker (including moving contact assemblies, operating mechanism linkages, etc.) need 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. The dual improvement in moving mass and speed will cause the collision energy at the moment of contact closure during the closing process to increase nonlinearly, and the impact force and energy generated during the collision will increase significantly with the voltage level. The cup-shaped longitudinal magnetic contacts used in traditional vacuum circuit breakers 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 cause problems such as end face indentation, edge deformation, and damage to the longitudinal magnetic groove structure in traditional cup-shaped longitudinal magnetic contacts. These structural damages not only disrupt the uniformity of the longitudinal magnetic field distribution and reduce arc-extinguishing efficiency, but also increase contact resistance, leading to localized overheating and shortening contact lifespan. In more severe cases, they can cause vacuum interrupter chamber seal failure and insulation breakdown, directly threatening the safe and stable operation of the entire power system and causing significant economic losses. Against this backdrop, how to significantly improve the mechanical strength of cup-shaped longitudinal magnetic contacts while ensuring their conductivity and magnetic permeability 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, the present invention aims to propose a structurally reinforced longitudinal magnetic contact and its application in a vacuum interrupter. This innovative structural design effectively solves the problem of contact collision deformation at high voltage levels, providing 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 structurally reinforced longitudinal magnetic contact includes a stationary contact assembly structure 201 and a moving contact assembly structure 202;

[0008] The stationary contact assembly structure 201 includes a stationary conductive rod 101, a stationary excitation contact seat 102, a stationary stainless steel cup seat 103, and a stationary contact plate 104. The stationary conductive rod 101 is fixed to the bottom of the stationary excitation contact seat 102, and the stationary contact plate 104 is fixed to the top of the stationary excitation contact seat 102. The stationary wing structure 302 attached to the stationary stainless steel cup seat 103 matches the stationary oblique slot 301 of the stationary excitation contact seat 102. The stationary wing structure 302 is installed in the stationary oblique slot 301 and serves as a support. The slotted structures on the stationary contact plate 104 are all connected to the stationary oblique slot 301 on the stationary excitation contact seat 102.

[0009] The moving end contact assembly structure 202 includes a moving end conductive rod 108, a moving end excitation contact seat 107, a moving end stainless steel cup seat 106, and a moving end contact piece 105. The moving end conductive rod 108 is fixed to the bottom of the moving end excitation contact seat 107, and the moving end contact piece 105 is fixed to the top of the moving end excitation contact seat 107. The moving end wing structure 304 attached to the moving end stainless steel cup seat 106 matches the moving end oblique slot 303 of the moving end excitation contact seat 107. The wing structure 304 is installed in the moving end oblique slot 303 and plays a supporting role. The slotted structure on the moving end contact piece 105 is connected to the moving end oblique slot 303 on the moving end excitation contact seat 107.

[0010] The stationary stainless steel cup holder 103 can be installed and fixed inside or outside the stationary excitation contact holder 102; when it is fixed inside the stationary excitation contact holder 102, the stationary wing structure 302 extends outward on the outer surface of the stationary stainless steel cup holder 103; when it is fixed outside the stationary excitation contact holder 102, the stationary wing structure 302 extends inward on the inner surface of the stationary stainless steel cup holder 103.

[0011] The moving end stainless steel cup holder 106 can be installed and fixed inside or outside the moving end excitation contact holder 107; when it is installed and fixed inside the moving end excitation contact holder 107, the moving end wing structure 303 is on the outer surface of the moving end stainless steel cup holder 106 and extends outward; when it is fixed outside the moving end excitation contact holder 107, the moving end wing structure 303 is on the inner surface of the moving end stainless steel cup holder 106 and extends inward.

[0012] The inner and outer surfaces of the stationary stainless steel cup holder 103 and the attached stationary wing structure 302 are coated with an insulating layer; the insulating layer material is a high-temperature resistant insulating material. The inner and outer surfaces of the moving stainless steel cup holder 106 and the attached moving wing structure 304 are coated with an insulating layer; the insulating layer material is a high-temperature resistant insulating material.

[0013] The number of stationary end wing structures 302 attached to the stationary end stainless steel cup holder 103 is equal to the number of stationary end oblique slots 301 of the stationary end excitation contact holder 102; the number of moving end wing structures 304 attached to the moving end stainless steel cup holder 107 is equal to the number of moving end oblique slots 303 of the moving end excitation contact holder 107.

[0014] The stationary stainless steel cup holder 103 can be a single unit or divided into multiple parts for easy assembly with the stationary excitation contact holder 102; the moving stainless steel cup holder 106 can be a single unit or divided into multiple parts for easy assembly with the moving excitation contact holder 107.

[0015] A vacuum interrupter includes a structurally reinforced longitudinal magnetic contact, 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 interrupter and welded to a 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.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] 1) Significantly enhanced contact mechanical strength. By combining a stainless steel cup holder reinforcement structure with a copper excitation contact holder, a "copper-steel" composite support structure can be formed. The copper material ensures the conductivity and magnetic permeability of the contact core, while the stainless steel reinforcement structure provides multi-dimensional mechanical support to the excitation contact holder through its annular body and outer reinforcing fins. This combined structure effectively disperses the impact force during closing collisions, preventing end-face dents or edge deformation of the copper contacts due to insufficient strength, significantly improving the overall deformation resistance of the contacts and meeting the stringent mechanical strength requirements of high-voltage circuit breakers.

[0018] 2) Ensuring stable electrical performance of the contacts. The inner and outer surfaces of both the stationary and moving stainless steel cup holders, as well as the surfaces of the protruding stationary and moving wing structures, are completely coated with an insulating layer. This insulating layer isolates electrical interference between the stainless steel and copper contacts, without affecting the current-carrying efficiency of the copper contacts or disrupting the magnetic field distribution of the longitudinal magnetic contacts, ensuring stable excitation performance. Simultaneously, the insulating layer prevents stray circuits from forming between the stainless steel components and other conductive parts, 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.

[0019] 3) Reduced machining and assembly difficulty. The stainless steel cup holder reinforcement structure is divided into multiple parts, adopting a modular design to optimize the machining process. Each modular component is smaller in size, avoiding the complex forming difficulties encountered when machining the overall structure and reducing the difficulty of precision control in CNC machining. During assembly, the modular reinforcement structure and the excitation contact seat can be assembled and positioned one by one before the whole structure is fixed, avoiding assembly misalignment caused by the large size of the structure, balancing machining feasibility and assembly accuracy, and improving production efficiency. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structurally reinforced longitudinal magnetic contact of the present invention.

[0021] Figure 2(a) is a front view of the stationary end excitation contact seat of the present invention.

[0022] Figure 2(b) is a front view of the moving end excitation contact seat of the present invention.

[0023] Figure 3(a) is a front view of the stationary stainless steel cup holder of the present invention.

[0024] Figure 3(b) is a front view of the moving end stainless steel cup holder of the present invention.

[0025] Figure 4 This is a side view of a 1 / 3 disassembled component of the stainless steel cup holder of the present invention.

[0026] Figure 5(a) is a schematic diagram of the stainless steel cup holder of the stationary end of the present invention and its corresponding stationary end excitation contact holder with slotted structure and stationary end contact piece matching.

[0027] Figure 5(b) is a schematic diagram of the stainless steel cup holder of the moving end of the present invention and its corresponding moving end excitation contact holder with slotted structure and moving end contact piece matching.

[0028] Figure 6 This is a plan view of the vacuum interrupter chamber of the application structure reinforced longitudinal magnetic contact of the present invention. Detailed Implementation

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] like Figure 1 The diagram shown is a schematic of the structurally reinforced longitudinal magnetic contact of the present invention. The stationary contact assembly structure 201 includes a stationary conductive rod 101, a stationary excitation contact seat 102, a stationary stainless steel cup seat 103, and a stationary contact plate 104; the stationary conductive rod 101 is welded to the bottom of the stationary excitation contact seat 102, and the stationary contact plate 104 is welded to the top of the stationary excitation contact seat 102; the stationary wing structure 302 attached to the stationary stainless steel cup seat 103 matches the stationary oblique slot 301 of the stationary excitation contact seat 102; the stationary wing structure 302 is installed within the stationary oblique slot 301 and provides support; the moving contact assembly structure 202 includes a moving conductive rod 108, a moving... The moving end excitation contact seat 107 comprises a moving end stainless steel cup seat 106 and a moving end contact piece 105. The moving end conductive rod 108 is welded to the bottom of the moving end excitation contact seat 107, and the moving end contact piece 105 is welded to the top of the moving end excitation contact seat 107. The moving end wing structure 304 attached to the moving end stainless steel cup seat 106 matches the moving end oblique slot 303 of the moving end excitation contact seat 107. The moving end wing structure 304 is installed in the moving end oblique slot 303 and serves as a support. The stationary end excitation contact seat 102 and the moving end excitation contact seat 107 are positioned to match, generating a certain longitudinal magnetic field in the contact gap during the arcing stage.

[0031] Figures 2(a) and 2(b) show front views of the stationary excitation contact seat and the moving excitation contact seat of the present invention. The stationary excitation contact seat 102 has a stationary oblique slot 301 that prevents eddy current generation and facilitates the generation of a longitudinal magnetic field. The stationary oblique slot 301 divides the stationary excitation contact seat 102 into discontinuous regions, directly cutting off the closed loop of eddy current. The slot increases the current path length and resistance, further weakening the eddy current intensity. At the same time, the longitudinal current component along the stationary excitation contact seat 102 superimposes to generate a longitudinal magnetic field, improving the arc extinguishing performance of the contact. The moving end excitation contact base 107 features a moving end oblique slot 303 that prevents eddy current generation and facilitates the generation of a longitudinal magnetic field. The oblique slot 303 divides the moving end excitation contact base 107 into discontinuous regions, directly cutting off the closed loop of eddy currents. The slot increases the current path length and resistance, further weakening the eddy current intensity. Simultaneously, the longitudinal current components along the moving end excitation contact base 107 superimpose to generate a longitudinal magnetic field, improving the contact's arc-extinguishing performance. While reducing the eddy current effect, it also reduces the residual magnetic field lag time, facilitating the recovery of the insulating medium strength after the current crosses zero, and reducing the risk of anode ablation.

[0032] Figures 3(a) and 3(b) show front views of the stationary and moving stainless steel cup holders of the present invention. The stationary stainless steel cup holder structure 103 has a stationary wing structure 302 that matches the stationary oblique slot 301 of the stationary excitation contact holder 102, and the moving stainless steel cup holder structure 106 has a moving wing structure 304 that matches the moving oblique slot 303 of the moving excitation contact holder 107. Through combination, the mechanical structure of the contact is greatly strengthened. At the same time, the inner and outer surfaces of the stationary stainless steel cup holder structure 103 and the moving stainless steel cup holder structure 106, as well as the surfaces of the stationary wing structure 302 and the moving wing structure 304, are coated with an insulating layer, so that the stainless steel cup holder reinforcement structure does not adversely affect the insulation, current carrying, and excitation performance of the contact.

[0033] like Figure 4 The image shown is a side view of one-third of the disassembled stainless steel cup holder of the present invention. For ease of processing, the stainless steel cup holder is divided into three symmetrical parts for processing. Since the stationary and moving ends of the stainless steel cup holder have the same structure, it facilitates overall manufacturing. During use, only the parts need to be assembled, making assembly convenient and quick.

[0034] Figures 5(a) and 5(b) show schematic diagrams of the stainless steel cup holder of the present invention and its corresponding slotted excitation contact holder. The slotted directions of the stationary contact piece 104 and the moving contact piece 105 are matched, and their slotted directions are aligned. The slotted structures on the stationary contact piece 104 are all connected to the stationary oblique slots 301 on the stationary excitation contact holder 102; the slotted structures on the moving contact piece 105 are all connected to the moving oblique slots 303 on the moving excitation contact holder 107, so as to ensure that a stable longitudinal magnetic field is generated in the contact gap during the arcing stage. Meanwhile, the stationary end wing structure 302 of the stationary end stainless steel cup holder 103 precisely engages with the stationary end oblique slot 301 of the stationary end excitation contact holder 102, and the moving end wing structure 304 of the moving end stainless steel cup holder 106 precisely engages with the moving end oblique slot 303 of the moving end excitation contact holder 107, thus enhancing mechanical strength without interfering with the magnetic field distribution.

[0035] like Figure 6As shown, the arrangement of the guide rod and contacts in the vacuum interrupter is the same as that of a conventional interrupter. From top to bottom, there is the stationary end cover plate 121 of the interrupter and the stationary end conductive rod 101 passing through the center of the stationary end cover plate 121. The stationary end contact assembly structure 201 consists of the stationary end conductive rod 101, the stationary end excitation contact seat 102, the stationary end stainless steel cup seat 103, and the stationary end contact piece 104 with a slotted structure. The stationary end cover plate 121 of the interrupter is connected to the stationary end insulating shell 123. The stationary end insulating shell 123 is connected to the moving end insulating shell 125. The moving end cover plate 127 of the interrupter is placed on the lower side of the interrupter and is connected to the moving end conductive rod 108. The moving end contact assembly structure 202 consists of the moving end conductive rod 108, the moving end excitation contact seat 107, the moving end stainless steel cup seat 106, and the moving end contact piece 105 with a slotted structure. Inside the arc-extinguishing chamber, from top to bottom, are a stationary end shield 122, a central shield 124, and a moving end shield 126.

[0036] This invention is not limited to the preferred embodiments described above. Those skilled in the art can make modifications and variations to the high-current-capacity contact structure vacuum interrupter and its application in vacuum circuit breakers based on the teachings of this invention. All such modifications and variations should fall within the protection scope of this invention.

Claims

1. A structurally reinforced longitudinal magnetic contact, 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 excitation contact seat (102), a stationary stainless steel cup seat (103), and a stationary contact plate (104). The stationary conductive rod (101) is fixed to the bottom of the stationary excitation contact seat (102), and the stationary contact plate (104) is fixed to the top of the stationary excitation contact seat (102). The stationary wing structure (302) attached to the stationary stainless steel cup seat (103) matches the stationary oblique slot (301) of the stationary excitation contact seat (102). The stationary wing structure (302) is installed in the stationary oblique slot (301) and plays a supporting role. The slotted structure on the stationary contact plate (104) is connected to the stationary oblique slot (301) on the stationary excitation contact seat (102). The moving end contact assembly structure (202) includes a moving end conductive rod (108), a moving end excitation contact seat (107), a moving end stainless steel cup seat (106), and a moving end contact piece (105). The moving end conductive rod (108) is fixed to the bottom of the moving end excitation contact seat (107), and the moving end contact piece (105) is fixed to the top of the moving end excitation contact seat (107). The moving end wing structure (304) attached to the moving end stainless steel cup seat (106) matches the moving end oblique slot (303) of the moving end excitation contact seat (107). The moving end wing structure (304) is installed in the moving end oblique slot (303) and plays a supporting role. The slot structure on the moving end contact piece (105) is connected to the moving end oblique slot (303) on the moving end excitation contact seat (107). The stationary stainless steel cup holder (103) is installed and fixed inside or outside the stationary excitation contact holder (102); when it is fixed inside the stationary excitation contact holder (102), the stationary wing structure (302) extends outward on the outer surface of the stationary stainless steel cup holder (103); when it is fixed outside the stationary excitation contact holder (102), the stationary wing structure (302) extends inward on the inner surface of the stationary stainless steel cup holder (103). The moving end stainless steel cup holder (106) is installed and fixed inside or outside the moving end excitation contact holder (107); when it is installed and fixed inside the moving end excitation contact holder (107), the moving end wing structure (304) extends outward on the outer surface of the moving end stainless steel cup holder (106); when it is fixed outside the moving end excitation contact holder (107), the moving end wing structure (304) extends inward on the inner surface of the moving end stainless steel cup holder (106). The inner and outer surfaces of the stationary stainless steel cup holder (103) and the attached stationary wing structure (302) are coated with an insulating layer; the insulating layer material is a high-temperature resistant insulating material. The inner and outer surfaces of the moving end stainless steel cup holder (106) and the attached moving end wing structure (304) are coated with an insulating layer; the insulating layer material is a high-temperature resistant insulating material.

2. The structurally reinforced longitudinal magnetic contact according to claim 1, characterized in that: The number of stationary end wing structures (302) attached to the stationary end stainless steel cup holder (103) is equal to the number of stationary end oblique slots (301) of the stationary end excitation contact holder (102); the number of moving end wing structures (304) attached to the moving end stainless steel cup holder (106) is equal to the number of moving end oblique slots (303) of the moving end excitation contact holder (107).

3. The structurally reinforced longitudinal magnetic contact according to claim 1, characterized in that: The stationary stainless steel cup holder (103) is a whole or divided into multiple parts, which facilitates assembly with the stationary excitation contact holder (102); the moving stainless steel cup holder (106) is a whole or divided into multiple parts, which facilitates assembly with the moving excitation contact holder (107).

4. A vacuum interrupter, characterized in that: The vacuum interrupter includes a structurally reinforced longitudinal magnetic contact as described in any one of claims 1-3, 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 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.

Images