252kv three-position disconnecting switch movable contact fixed structure

Abstract

The application belongs to the technical field of power switch equipment, and particularly relates to a 252kV three-position disconnecting switch movable contact fixing structure with shared gas chamber for different phases. The 252kV three-position disconnecting switch movable contact fixing structure with shared gas chamber for different phases comprises a switch body, and isolation movable contacts and grounding movable contacts are arranged in the switch body, characterized in that: the isolation movable contacts are made of copper material, the grounding movable contacts are made of aluminum material, T-shaped grooves are arranged on the isolation movable contacts and the grounding movable contacts, racks are clamped in the T-shaped grooves, two T-shaped blocks are integrally connected to the racks, and baffle plates are respectively connected to the outer sides of the two T-shaped blocks. The application has the beneficial effects that: efficient and accurate disassembly and assembly of the rack assembly are realized, and the installation and maintenance efficiency is greatly improved; meanwhile, physical isolation of the gear and rack meshing area from the conductive spring and the contact area of the contact finger is realized, the scratching damage of the conductive parts in the meshing process is avoided, and the operation reliability and service life of the product are improved.

Description

Technical Field

[0001] This invention belongs to the technical field of power switchgear, and specifically relates to a fixing structure for the moving contact of a 252kV phase-separated common gas chamber three-position disconnecting switch. Background Technology

[0002] Combined electrical equipment is the core equipment in a power system responsible for line switching and fault protection. Current carrying capacity and insulation level are key considerations in its design. The 252kV phase-separated common-chamber three-position isolating grounding switch is an important component of 220kV substation switches. The reliability of the contact between the moving and stationary contacts and the stability of the transmission mechanism directly determine the equipment's safe operating level.

[0003] Typically, transmission uses a rack and pinion system. The gears are fixed in the slots of each phase's moving contact and connected to the mechanism's output shaft via inter-phase insulated shafts. The rack is fixed in the moving contact, and the gear and rack work together to achieve closing and opening operations. Since the moving and stationary contacts conduct current and bear electrodynamic forces through conductive springs, the rack and pinion fixing structure is crucial. It must ensure meshing accuracy during transmission while preventing damage to core conductive components such as the conductive springs and contact fingers.

[0004] Currently, the following problems are commonly found in the industry regarding the gear and rack transmission method for moving and stationary contacts in combined electrical appliances, as well as the fixing method between the rack and the conductor: 1. Cumbersome installation and maintenance: Traditional racks are mostly connected to the moving contact by welding, multiple screw fastening or integral embedding. During installation, the meshing position needs to be repeatedly adjusted. During disassembly and maintenance, the entire moving contact assembly needs to be disassembled, which is time-consuming and labor-intensive and cannot meet the modular and high-efficiency operation and maintenance requirements of modern power equipment. 2. Conductive components are easily damaged: The boundary between the fixed position of the rack and the installation area of ​​the conductive spring and the contact finger is unclear. The axial movement and radial offset generated when the gear and rack mesh can easily scrape the surface of the conductive spring and the contact finger, resulting in wear of conductive components, loss of elasticity, increased contact resistance, and causing equipment overheating, discharge or even short circuit failure. 3. Poor stability of the fixed structure: Existing anti-detachment designs are mostly single-sided blocks or single pressure plates, which cannot effectively limit the multi-directional movement of the rack. Under long-term opening and closing impacts, the rack is prone to loosening and detachment, further aggravating the scratch damage to the conductive components. 4. Insufficient structural adaptability: The moving contacts are mostly designed with a single material, and the conductive area and the transmission area are not clearly distinguished. The impact force during the transmission process is directly transmitted to the conductive components, causing additional fatigue damage to the conductive springs and contact fingers, and reducing the service life of the equipment. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, this invention provides a fixed structure for the moving contact of a 252kV phase-separated common gas chamber three-position disconnecting switch.

[0006] This invention is achieved through the following technical solution: A 252kV phase-separated common-gas-chamber three-position disconnector moving contact fixing structure includes a switch body, within which an isolation moving contact and a grounding moving contact are provided. The isolation moving contact is made of copper, and the grounding moving contact is made of aluminum. T-slots are formed on both the isolation and grounding moving contacts, and racks are fitted into the T-slots. Two T-blocks are integrally connected to the racks, and baffles are connected to the outer sides of the two T-blocks respectively.

[0007] The bottom of the baffle is embedded in the isolation moving contact or the grounding moving contact.

[0008] The height of the rack is lower than that of the isolating moving contact and the grounding moving contact.

[0009] The rack meshes with the gear, which is mounted on the gear shaft.

[0010] The end edge of the rack is provided with an R2 chamfer.

[0011] The isolating moving contact and the grounding moving contact are fixed together by the first bolt.

[0012] The T-shaped block and the baffle are connected and fixed by a second bolt.

[0013] The beneficial effects of this invention are: through the innovative triple fixing structure design, efficient and precise disassembly and assembly of the rack and pinion assembly are achieved, greatly improving installation and maintenance efficiency; at the same time, by optimizing the structural layout and dimensional parameters of the moving contact, physical isolation is achieved between the gear and rack meshing area and the conductive spring and contact finger contact area, avoiding scratch damage to conductive components during meshing, and ultimately improving the operational reliability and service life of the product. Attached Figure Description

[0014] The invention will now be further described with reference to the accompanying drawings.

[0015] Appendix Figure 1 This is a schematic diagram of the structure of the present invention; Appendix Figure 2 This is a schematic diagram of the rack and gear mating structure of the present invention; Appendix Figure 3 This is a schematic diagram of the overall assembly structure of the present invention; In the diagram, 1 is the switch body, 2 is the isolating moving contact, 3 is the grounding moving contact, 4 is the T-slot, 5 is the rack, 6 is the T-block, 7 is the baffle, 8 is the gear, 9 is the gear shaft, 10 is the R2 chamfer, 11 is the first bolt, 12 is the second bolt, and 13 is the conductive component. Detailed Implementation

[0016] The attached figure illustrates a specific embodiment of the present invention. This embodiment includes a copper-aluminum spliced ​​moving contact body, a rack and pinion assembly, a high-efficiency anti-detachment fixing assembly, and a conductive assembly 13.

[0017] 1. Copper-aluminum spliced ​​moving contact body The moving contact structure adopts a copper-aluminum splicing structure. The isolating moving contact 2 is made of copper to ensure stable current flow under the same cross-section; the grounding moving contact 3 is made of aluminum, and considering the application requirements, it has the ability to withstand dynamic and thermal stability (125kA / 0.3s, 50kA / 3s). The copper and aluminum are connected by a concave-convex surface fit and the first bolt 11. The copper-aluminum moving contact has a T-slot 4 for mounting the rack 5 to bear the transmission load of the gear 8 meshing. The rack 5 meshes with the gear 8 and is lower than the contact structure on both sides, which achieves physical isolation between the transmission area and the conductive area from the structure, avoiding the gear and rack meshing from affecting the conductive component 13.

[0018] 2. High-efficiency slot snap-fit ​​design of rack and pinion assembly The fixed end of the rack 5 adopts a double T-shaped structure, giving the rack 5 a sufficiently large fixed end cross-section. The copper and aluminum parts of the moving contact are pre-set with T-slots 4 that are compatible with the rack 5, with a slot depth of 20mm and a width tolerance controlled within ±0.03mm. The inner side of the rack assembly has an integrally formed T-block 6 that precisely matches the slot. During installation, the rack assembly only needs to be pushed in along the slot to complete the initial positioning, without the need for repeated adjustments to the meshing accuracy. Compared with the traditional structure, the installation time is reduced by 70%. The rack 5 and the T-slot 4 are precisely positioned, and the conductive component 13 is higher than the rack, completely eliminating the scratching of the conductive component 13 by meshing movement.

[0019] 3. High-efficiency anti-detachment fixing components (easy disassembly and assembly design) The high-efficiency anti-detachment fixing component includes symmetrical double limiting plates and end positioning aluminum plates, achieving stable fixation and quick assembly / disassembly of the rack assembly. The symmetrical double limiting plates consist of two baffles 7, symmetrically fixed to both sides of the copper and aluminum moving contact transmission ends by two countersunk second bolts 12. The bottom of the limiting plates extends into the copper and aluminum contact retainers, effectively restricting the axial movement of the rack 5. The symmetrical design of the double limiting plates disperses the meshing impact force, increasing impact resistance by 80% compared to single-sided limiting. Disassembly only requires loosening two bolts to remove the limiting plates, making operation convenient.

[0020] 4. Size-optimized design for protective conductive components The tooth tip height and tooth root height dimensions of the rack assembly are optimized so that the meshing center line of gear 8 and rack 5 is ≥40mm from the center line of conductive component 13. The lateral force generated by meshing is entirely borne by the copper and aluminum moving contact transmission section and is not transmitted to conductive component 13. At the same time, the end edge of the rack assembly is chamfered by R2 10 to prevent the conductive spring and contact finger from being scratched during the disassembly and assembly of rack 5. Conductive component 13 includes a multi-layer watchband-style conductive spring and silver-plated contact finger, which are installed in the preset groove of the copper conductive section. The contact pressure when in contact with the stationary contact is 150-200N to ensure stable current flow.

[0021] 5. Overall compatibility with high-voltage circuit breaker design The guide surface of the moving contact body is fitted with the inner guide rail of the intermediate conductor of the 252kV phase-separated common gas chamber three-position isolating grounding switch with a clearance of 0.08-0.12mm to ensure that the moving contact moves smoothly during the opening and closing process without the risk of jamming.

[0022] The 252kV phase-separated common-gas-chamber three-position isolating switch moving contact fixing structure of this invention adopts a copper-aluminum splicing structure for the isolating and grounding switch moving contact. The isolating position is made of copper to ensure current carrying capacity, while the grounding position is made of aluminum. The copper-aluminum mating surface adopts a concave-convex splicing structure, with coaxiality tolerance controlled within 0.1mm. The conductors are internally connected and fixed with M12 bolts, and the output torque is retested using a torque wrench.

[0023] The moving contact has a double T-slot 4 pre-installed, and the rack 5 is designed with a T-shaped structure. During installation, the rack 5 is pushed in along the T-slot 4 to ensure proper engagement with the slot. This ensures meshing accuracy with the gear assembly without additional adjustment; this is the first fixing method. The copper and aluminum ends of the moving contact are symmetrically fixed with baffles 7 and tightened with bolts to prevent the rack 5 from shifting; this is the second fixing method.

[0024] The isolating moving-end conductive rod is sealed and fixed at its end with a copper-tungsten contact plate. This ensures that the main contacts will not be burned when the isolating switch is opened, and also prevents the rack 5 from falling off when gear 8 and rack 5 are engaged. This is the third fixing method. The rack 5 is installed in the moving contact, below the copper-aluminum end of the moving contact, and all sharp corners are chamfered. The conductive rod spring is installed in the moving contact. The assembled moving contact is aligned with the neutral / grounding position by the engagement of gear 8 and rack 5. The surface of the moving contact is fitted with the conductive rod spring, and the end edge of rack 5 is chamfered with R2 to prevent scratching the conductive spring during disassembly and assembly.

Claims

1. A fixed structure for the moving contact of a 252kV phase-separated common-gas chamber three-position disconnecting switch, comprising a switch body (1), wherein the switch body (1) is provided with an isolating moving contact (2) and a grounding moving contact (3), characterized in that: The isolating moving contact (2) is made of copper, and the grounding moving contact (3) is made of aluminum. T-slots (4) are provided on the isolating moving contact (2) and the grounding moving contact (3). A rack (5) is installed in the T-slot (4). Two T-blocks (6) are integrally connected on the rack (5). Baffles (7) are connected to the outside of the two T-blocks (6) respectively.

2. The moving contact fixing structure of the 252kV phase-separated common-gas chamber three-position disconnector switch according to claim 1, characterized in that: The bottom of the baffle (7) is embedded in the isolation moving contact (2) or the grounding moving contact (3).

3. The moving contact fixing structure of the 252kV phase-separated common-gas chamber three-position disconnector switch according to claim 1, characterized in that: The height of the rack (5) is lower than that of the isolating moving contact (2) and the grounding moving contact (3).

4. The moving contact fixing structure of the 252kV phase-separated common gas chamber three-position disconnector switch according to claim 1, characterized in that: The rack (5) meshes with the gear (8), which is mounted on the gear shaft (9).

5. The moving contact fixing structure of the 252kV phase-separated common-gas chamber three-position disconnector switch according to claim 4, characterized in that: The end edge of the rack (5) is provided with an R2 chamfer (10).

6. The moving contact fixing structure of the 252kV phase-separated common-gas chamber three-position disconnector switch according to claim 1, characterized in that: The isolating moving contact (2) and the grounding moving contact (3) are connected and fixed by the first bolt (11).

7. The moving contact fixing structure of the 252kV phase-separated common-gas chamber three-position disconnector switch according to claim 1, characterized in that: The T-block (6) and the baffle (7) are connected and fixed by the second bolt (12).

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