A 145kV large capacity three-position isolation grounding switch

Abstract

The application discloses a 145KV large-capacity three-position isolation grounding switch, which comprises a shell and a three-phase conductor mechanism arranged in the shell, the lateral wall and the bottom of the shell are respectively provided with insulators one and two, the lateral wall on the vertical side of the insulator one on the shell is provided with a control mechanism, the shell on the symmetric side of the insulator one is fixedly connected with a cover plate through bolts, the cover plate is provided with a heat dissipation assembly, the three-phase conductor mechanism is composed of three groups of parallel conductor assemblies, each group of the conductor assemblies comprises a static contact conductor and a support conductor, the lateral wall of the middle part of the static contact conductor is fixedly provided with an isolation moving contact through bolts, the support conductor is installed with an isolation static contact, and the top of the isolation static contact is provided with a grounding static contact. The application belongs to the technical field of high-voltage electrical equipment, and particularly relates to a 145KV large-capacity three-position isolation grounding switch which is compact in structure, efficient in heat dissipation and reliable in three-position mechanical interlocking.

Description

Technical Field

[0001] This invention belongs to the field of high-voltage electrical equipment technology, specifically referring to a 145kV high-capacity three-position isolating grounding switch. Background Technology

[0002] 145kV switchgear has been widely used in urban power grids and transmission hubs, but the rated current of existing isolating grounding switches of the same voltage level is generally only 3150A. With the continuous increase in urban load density and the continuous expansion of power grid transmission capacity, traditional switchgear has significant technical shortcomings:

[0003] 1. Under long-term operation with high current, the conductor heats up severely, the temperature rise exceeds the standard, the heat dissipation structure is rudimentary, and it cannot withstand the 5000A high-capacity current carrying conditions;

[0004] 2. The isolation and grounding are arranged separately, resulting in a large equipment footprint. The three-phase box structure is bulky and not conducive to the miniaturization of substations.

[0005] 3. The isolation and grounding actions lack reliable mechanical interlocking, which can easily lead to misoperation and pose safety hazards such as phase-to-phase short circuits and personal grounding.

[0006] 4. When a large current flows, the electrodynamic impact is large, and the lack of contact guidance and electric field optimization structure makes it easy to have contact wear and discharge problems with excessively high local electric field strength.

[0007] Therefore, the industry urgently needs to develop a 145kV three-position isolating grounding switch with a compact structure, efficient heat dissipation, reliable three-position mechanical interlocking, and a rated current of 5000A. Summary of the Invention

[0008] To address the shortcomings of existing 145kV isolating grounding switches, such as low current capacity, poor heat dissipation, large equipment size, and unreliable safety interlocking, this invention provides a 145kV high-capacity three-position isolating grounding switch. It achieves a three-phase conductor co-enclosure arrangement and a rated current of 5000A. A composite heat dissipation structure of heat pipes and heat dissipation grids is adopted to solve the problem of high-current temperature rise. Three-position mechanical interlocking is achieved through a gear and rack linear drive, eliminating the risk of misoperation of the isolating and grounding switches. Simultaneously, the contact electric field distribution is optimized, improving the operational stability of the equipment.

[0009] The technical solution adopted by this invention is as follows: This invention proposes a 145kV high-capacity three-position isolating grounding switch, including a housing and a three-phase conductor mechanism disposed within the housing. The side wall and bottom of the housing are respectively provided with insulator one and insulator two, and insulator one and insulator two are fixedly connected to the flange of the housing by bolts. An operating mechanism is provided on the side wall of the housing perpendicular to insulator one, and the operating mechanism is connected to the three-phase conductor mechanism. A cover plate is fixedly connected to the other side of the housing and the insulator by bolts. A heat dissipation component is provided on the cover plate, and the heat dissipation component is used to quickly dissipate the heat generated by the conductors inside the equipment.

[0010] As an improvement to this solution, the three-phase conductor mechanism consists of three sets of parallel conductor assemblies. Each set of conductor assemblies includes a stationary contact conductor and a support conductor. An isolating stationary contact is fixed to the side wall of the middle part of the stationary contact conductor by bolts. An isolating moving contact is installed on the support conductor, and a grounding stationary contact is provided above the isolating moving contact. The parallel arrangement of the three sets of conductor assemblies realizes the three-phase conductors in a common box arrangement, reducing the overall volume occupied by the equipment.

[0011] As an improvement to this solution, the central inserts of insulator one and insulator two are provided with threaded holes. The stationary contact conductor and the support conductor are fixedly connected to the threaded holes of the central inserts of insulator two and insulator one respectively by bolts. Insulator one and insulator two are used to provide insulation support for the internal high-voltage conductor.

[0012] Furthermore, the isolating moving contact, isolating stationary contact, and grounding stationary contact are coaxially arranged, and their axes are set at 30° to the horizontal line. The conductor part of the grounding stationary contact is fixed to the top of the housing by bolts. This arrangement allows the isolating moving contact to switch to only three positions: isolation closing, grounding closing, and complete opening, thus achieving mechanical interlocking between the isolation circuit and the grounding circuit.

[0013] Furthermore, each of the supporting conductors is rotatably connected to an insulating shaft, and the supporting conductor is provided with a drive assembly corresponding to the insulating shaft. The insulating shaft is used to transmit the power output by the operating mechanism, and the drive assembly is used to convert the rotational motion of the insulating shaft into the linear motion of the isolating moving contact.

[0014] Furthermore, the three sets of insulating shafts are connected by splines and keyways to achieve synchronous rotation. One set of insulating shafts for one phase is connected to the operating mechanism and is responsible for power input. The other two sets of insulating shafts distribute power to the three-phase conductor mechanism to realize the opening and closing operation, ensuring that the three-phase isolating moving contacts operate synchronously.

[0015] Furthermore, the drive assembly includes gears and racks, each with three sets. The rack is slidably connected to the cavity at the upper end of the supporting conductor. This cavity serves as a guide, restricting the rack's movement trajectory to resist the impact of high-current electrodynamic forces. The isolating moving contact is connected to the rack. The gear is fixed to the insulating shaft, and the rack meshes with the gear.

[0016] Furthermore, the isolating moving contact consists of a moving contact conductor and a shield. The moving contact conductor is fixed to the rack by bolts, and the shield is fitted over both ends of the moving contact conductor and fixed to the supporting conductor by screws, thereby achieving a uniform electric field and suppressing high-voltage partial discharge.

[0017] Furthermore, the heat dissipation component consists of a heat dissipation grid and heat pipes, and the heat dissipation grid and heat pipes are welded and fixed to the cover plate. The heat pipes extend into the shell and are filled with a heat exchange medium. The heat pipes absorb internal heat quickly by relying on the phase change of the medium and transfer it to the external heat dissipation grid to complete the heat dissipation.

[0018] Furthermore, the three-phase conductors of this switch are arranged in a common enclosure, and the rated current of the equipment is 5000A.

[0019] The beneficial effects achieved by the present invention using the above structure are as follows:

[0020] 1. The three-phase conductors are arranged in a common box, resulting in a compact overall structure and small equipment size, making it suitable for installation scenarios of compact GIS equipment;

[0021] 2. The heat pipe combined with the heat dissipation grid composite heat dissipation structure has strong heat dissipation capacity, and the equipment current carrying capacity can reach 5000A, effectively controlling the temperature rise during high current operation;

[0022] 3. The 30° coaxial three-position contact structure achieves native mechanical interlocking, eliminating misoperation of isolation and grounding circuits;

[0023] 4. The spline-linked insulated shaft is paired with a gear and rack linear transmission, enabling the three-phase contacts to move synchronously, supporting the conductor cavity to limit the movement and resist electrodynamic impact, and ensuring smooth contact operation;

[0024] 5. Shielding covers are installed at both ends of the moving contact to create a uniform electric field, reduce the risk of partial discharge, and extend the service life of the equipment. Attached Figure Description

[0025] Figure 1 This is a cross-sectional view of a 145kV high-capacity three-position isolating grounding switch proposed in this invention, taken from the front view.

[0026] Figure 2 This is a top-view cross-sectional view of a 145kV high-capacity three-position isolating grounding switch proposed in this invention.

[0027] Figure 3 This is a schematic diagram of the structure of the isolating moving contact component of a 145kV high-capacity three-position isolating grounding switch proposed in this invention.

[0028] The components are as follows: 1. Housing; 2. Three-phase conductor mechanism; 3. Operating mechanism; 4. Insulator 1; 5. Insulator 2; 6. Cover plate; 7. Heat dissipation assembly; 8. Stationary contact conductor; 9. Support conductor; 10. Isolating moving contact; 11. Isolating stationary contact; 12. Grounding stationary contact; 13. Insulating shaft; 14. Gear; 15. Drive assembly; 16. Rack; 17. Moving contact conductor; 18. Shielding cover; 19. Heat dissipation grid; 20. Heat pipe.

[0029] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. Detailed Implementation

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0031] like Figures 1-3 As shown, the present invention proposes a 145kV high-capacity three-position isolating grounding switch, which includes a housing 1, a three-phase conductor mechanism 2, an operating mechanism 3, an insulator 1 4, an insulator 2 5, a cover plate 6, and a heat dissipation assembly 7. The three-phase conductor mechanism 2 is assembled inside the housing 1 to realize the three-phase common enclosure arrangement.

[0032] Insulator 1 is mounted on the side wall of housing 1, and insulator 2 is mounted on the bottom of housing 1. Both insulator 1 and insulator 2 are bolted to the flange of housing 1. The central inserts of insulator 1 and insulator 2 are machined with threaded holes. The three-phase conductor mechanism 2 includes three sets of parallel conductor assemblies. Each set of conductor assemblies includes a stationary contact conductor 8 and a support conductor 9. The stationary contact conductor 8 and the support conductor 9 are bolted to the threaded holes of the central inserts of insulator 2 and insulator 1, respectively. The high-voltage conductor is supported by insulator 1 and insulator 2 to ground.

[0033] An operating mechanism 3 is installed on the side wall of the housing 1 perpendicular to the insulator 4. The operating mechanism 3 is driven by the three-phase conductor mechanism 2 to output operating power. On the other side of the housing 1 and the insulator 4, a cover plate 6 is fixed by bolts. A heat dissipation assembly 7 is installed on the cover plate 6. The heat dissipation assembly 7 includes a heat dissipation grid 19 and a heat pipe 20. The heat dissipation grid 19 and the heat pipe 20 are welded to the surface of the cover plate 6. One end of the heat pipe 20 extends into the internal cavity of the housing 1. The heat pipe 20 is filled with a heat exchange medium. When the equipment is running, the heat generated by the conductor inside the housing 1 is quickly absorbed by the heat pipe 20 and conducted to the outer heat dissipation grid 19 through the phase change of the medium. The heat is continuously dissipated by air convection, thereby meeting the temperature rise control requirements of the 5000A large-capacity flow condition.

[0034] Within each conductor assembly, the stationary contact conductor 8 has an isolating stationary contact 11 fixed to its sidewall by bolts. An isolating moving contact 10 is mounted on the supporting conductor 9. A grounding stationary contact 12 is installed above the isolating moving contact 10, and the grounding stationary contact 12 conductor is fixed to the top of the housing 1 by bolts. The isolating moving contact 10 consists of two parts: a moving contact conductor 17 and a shield 18. The moving contact conductor 17 is fastened to the end face of the rack 16 by bolts and moves synchronously with the rack 16. The shield 18 is fitted onto both ends of the moving contact conductor 17 and is fixed to the supporting conductor 9 by screws. The shield 18 has clearance holes for the moving contact conductor 17 to pass through. During operation, the shield 18 smoothly transitions the electric field at the contact end, reduces the local field strength, avoids partial discharge under high voltage conditions, and improves the stability of the equipment's insulation operation.

[0035] The isolating moving contact 10, isolating stationary contact 11, and grounding stationary contact 12 are arranged coaxially, and the three share an axis that forms a 30° angle with the horizontal line. The moving contact conductor 17 of the isolating moving contact 10 can slide back and forth in a straight line along this axis, with only three independent working positions: the isolating closing position is when it is attached to the isolating stationary contact 11, the main circuit is connected and the grounding circuit is disconnected; the grounding closing position is when it is attached to the grounding stationary contact 12, the main circuit is disconnected and the equipment is reliably grounded; the isolating grounding opening position is when it is completely separated from the two sets of stationary contacts in the middle, and both circuits are disconnected. Mechanical interlocking is achieved by relying on the structural layout, and it is impossible to connect the isolation and grounding circuits at the same time.

[0036] Insulating shafts 13 are rotatably mounted on each supporting conductor 9. Drive components 15, each matching one of the insulating shafts 13, are installed inside the supporting conductor 9. The three insulating shafts 13 are connected end-to-end via splines and keyways to achieve synchronous rotation. The insulating shaft 13 at the outermost phase position is connected to the operating mechanism 3 as a power input. After the operating mechanism 3 outputs torque to drive this insulating shaft 13 to rotate, the remaining two phase insulating shafts 13 synchronously distribute power, ensuring that the three-phase conductor mechanism 2 synchronously performs opening and closing actions. The drive component 15 includes gears 14 and racks 16, with three sets of each. Gears 14 are fixedly mounted on the insulating shafts 13, and racks 16 are slidably mounted inside the cavity at the upper end of the supporting conductor 9. This cavity guides and limits the racks 16, offsetting the electrodynamic impact generated by large currents. The racks 16 and gears 14 mesh with each other. When the insulating shaft 13 drives the gears 14 to rotate, the meshing racks 16 reciprocate linearly along the cavity, directly driving the isolating moving contact 10 to complete the position switching.

[0037] Complete workflow of the whole machine: The operator drives the control mechanism 3 to output rotational torque, which is transmitted to the side phase insulated shaft 13. The three sets of insulated shafts 13 rotate synchronously by splines. The insulated shaft 13 drives the gear 14 fixed on the shaft to rotate synchronously. The gear 14 meshes and drives the rack 16 to slide linearly in the cavity of the supporting conductor 9. The rack 16 pulls the moving contact conductor 17 to move along the 30° axis, switching to three working positions: isolation closing, grounding closing, and complete opening, completing the switching of three working states: main circuit conduction, equipment grounding, and circuit complete disconnection. The heat generated by the equipment under the long-term operation of 5000A current is quickly discharged to the heat dissipation grid 19 on the outside of the cover plate 6 by the heat pipe 20 that extends into the shell 1, continuously dissipating heat and controlling the temperature rise of the equipment.

[0038] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. A 145kV high-capacity three-position isolating grounding switch, comprising a housing (1) and a three-phase conductor mechanism (2) disposed within the housing (1), characterized in that: The side wall and bottom of the housing (1) are respectively provided with insulator one (4) and insulator two (5), and insulator one (4) and insulator two (5) are fixed to the flange of the housing (1) by bolts. The side wall of the housing (1) perpendicular to the insulator one (4) is provided with an operating mechanism (3), and the operating mechanism (3) is connected to the three-phase conductor mechanism (2). The other side of the housing (1) and the insulator one (4) is fixedly connected with a cover plate (6) by bolts. The cover plate (6) is provided with a heat dissipation component (7). The three-phase conductor mechanism (2) consists of three sets of parallel conductor assemblies. Each set of conductor assemblies includes a stationary contact conductor (8) and a support conductor (9). An isolation stationary contact (11) is fixed to the side wall of the middle part of the stationary contact conductor (8) by bolts. An isolation moving contact (10) is installed on the support conductor (9), and a grounding stationary contact (12) is provided above the isolation moving contact (10). Both the central inserts of insulator one (4) and insulator two (5) are provided with threaded holes. The stationary contact conductor (8) and the support conductor (9) are fixedly connected to the threaded holes of the central inserts of insulator two (5) and insulator one (4) respectively by bolts.

2. The 145kV high-capacity three-position isolating grounding switch according to claim 1, characterized in that: The isolating moving contact (10), isolating stationary contact (11) and grounding stationary contact (12) are coaxially arranged, and the axes of the three are set at 30° with the horizontal line. The conductor part of the grounding stationary contact (12) is fixed to the top of the housing (1) by bolts.

3. A 145kV high-capacity three-position isolating grounding switch according to claim 1, characterized in that: Each of the supporting conductors (9) is rotatably connected to an insulating shaft (13), and the supporting conductor (9) is provided with a drive assembly (15) corresponding to the insulating shaft (13).

4. A 145kV high-capacity three-position isolating grounding switch according to claim 3, characterized in that: The three sets of insulating shafts (13) are connected by splines and keyways to achieve synchronous rotation. One set of insulating shafts (13) of the side phase is connected to the operating mechanism (3) and is responsible for power input. The other two sets of insulating shafts (13) distribute power to the three-phase conductor mechanism (2) to realize the opening and closing operation.

5. A 145kV high-capacity three-position isolating grounding switch according to claim 4, characterized in that: The drive assembly (15) includes a gear (14) and a rack (16), each of which has three sets. The rack (16) is slidably connected to the cavity at the upper end of the supporting conductor (9), which serves as a guide. The isolating moving contact (10) is connected to the rack (16). The gear (14) is fixed on the insulating shaft (13), and the rack (16) meshes with the gear (14).

6. A 145kV high-capacity three-position isolating grounding switch according to claim 5, characterized in that: The isolating moving contact (10) consists of a moving contact conductor (17) and a shield (18). The moving contact conductor (17) is fixed to the rack (16) by bolts. The shield (18) is fitted over both ends of the moving contact conductor (17) and fixed to the supporting conductor (9) by screws, thereby achieving a uniform electric field.

7. A 145kV high-capacity three-position isolating grounding switch according to claim 1, characterized in that: The heat dissipation assembly (7) consists of a heat dissipation grid (19) and a heat pipe (20), and the heat dissipation grid (19) and the heat pipe (20) are welded and fixed on the cover plate (6), wherein the heat pipe (20) is fitted into the shell (1).

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