Environment-friendly gas ring main-tie-up unit load switch and operation method thereof

Abstract

The application discloses an environmentally-friendly gas ring main-tube load switch and an operating method thereof. A linkage transmission device is arranged between a three-position isolating switch and a vacuum load switch arc-extinguishing chamber. The application discloses the design of the traditional vacuum load switch independent operating mechanism, and the vacuum arc-extinguishing chamber is driven by the three-position isolating switch operating mechanism in an integrated linkage mode, so that the overall structure of the equipment is simplified, and the manufacturing cost of the equipment is greatly reduced. The linkage transmission structure is arranged, the action sequence of the isolating switch and the vacuum arc-extinguishing chamber is strictly limited, the logic closed loop of the closing, opening and grounding working conditions is formed, the misoperation is completely eliminated, and the operation safety and the power supply reliability of the equipment are greatly improved.

Description

Technical Field

[0001] This invention relates to the technical field of 10kV distribution network ring main unit equipment, specifically to a new type of environmentally friendly gas ring main unit load switch, which is suitable for SF6-free ring main unit equipment using environmentally friendly insulating gases such as dry air and nitrogen. Background Technology

[0002] In 10kV urban distribution network systems, SF6 ring main units have been widely adopted due to their excellent insulation and arc-extinguishing performance. However, SF6 gas is a strong greenhouse gas, which does not align with the current trend of green and environmentally friendly power equipment development. Furthermore, SF6 ring main units are prone to gas leakage during long-term operation. Gas leakage directly leads to a significant drop in the insulation level of the unit, not only posing safety hazards but also requiring emergency power outages for maintenance, resulting in power supply company losses and severely impacting the reliability of the distribution network.

[0003] With the iterative development of environmentally friendly power technologies, environmentally friendly gas ring main units using dry air or nitrogen as insulating media are gradually replacing traditional SF6 ring main units. Existing SF6 ring main units rely on the air-blowing and magnetic-blowing characteristics of SF6 gas for arc extinguishing, resulting in a simple structure and compact size. However, environmentally friendly gases such as dry air and nitrogen lack active arc extinguishing capabilities. Traditional arc extinguishing methods, which rely solely on elongating the arc, significantly increase the overall size of the ring main unit, leading to low equipment integration.

[0004] To address the lack of arc-extinguishing capability in environmentally friendly gas ring main units, existing systems generally employ vacuum interrupter structures with independent disconnecting switches. Traditional vacuum load switches are operated by first closing the disconnecting switch via a three-position disconnecting switch operating mechanism, and then closing the vacuum load switch via the vacuum load switch operating mechanism. However, this requires a dedicated operating mechanism similar to a circuit breaker, resulting in complex equipment structure, significantly increased manufacturing costs, and an overall cost approaching that of a circuit breaker cabinet. This severely limits the widespread application of environmentally friendly gas ring main units. Therefore, there is an urgent need for a simplified, low-cost, and reliable load switch structure for environmentally friendly gas ring main units. Summary of the Invention

[0005] The purpose of this invention is to provide an environmentally friendly gas ring main unit load switch that simplifies the equipment operation structure, eliminates the independent vacuum operation mechanism, reduces equipment costs, and at the same time ensures the equipment's arc extinguishing performance and operational safety.

[0006] Another objective of this invention is to provide an operation method for canceling the load switch of the independent vacuum operating mechanism.

[0007] To achieve the above objectives, the present invention provides an environmentally friendly gas ring main unit load switch, comprising a three-position disconnect switch, a three-position operating mechanism, and a vacuum load switch arc-extinguishing chamber. The three-position operating mechanism is connected to the three-position disconnect switch via an insulating drive rod. A linkage transmission device is provided between the three-position disconnect switch and the vacuum load switch arc-extinguishing chamber. When the three-position operating mechanism drives the three-position disconnect switch to complete the switching of the opening, closing, and grounding positions, the linkage device controls the vacuum load switch arc-extinguishing chamber to synchronously open and close.

[0008] The linkage transmission device includes a lever on the three-position disconnect switch and a "Y"-shaped lever fork that is linked to the moving end of the arc-extinguishing chamber of the vacuum load switch. The lever on the three-position disconnect switch is rotatably inserted into the upper fork of the "Y"-shaped lever fork, and the lower end of the "Y"-shaped lever fork is connected to the moving end of the arc-extinguishing chamber of the vacuum load switch via a spring.

[0009] A linkage transmission device is installed between the three-position disconnector and the arc-extinguishing chamber of the vacuum load switch. When the load switch of the environmental gas ring main unit is closed, the three-position disconnector changes from the open state to the closed state. The three-position operating mechanism synchronously operates the arc-extinguishing chamber of the vacuum load switch to close through the linkage transmission device and is responsible for extinguishing the arc generated by the closing and connection of the load switch of the environmental gas ring main unit. When the switch is opened, the three-position operating mechanism drives the arc-extinguishing chamber of the vacuum load switch to open first through the linkage transmission device, extinguishing the arc generated by the interruption of the load current. When grounding occurs, the grounding switch closes first, and the arc-extinguishing chamber of the vacuum load switch closes later. If the switch closes to the power supply point, the short circuit closing is formed, and the arc is extinguished by the vacuum arc-extinguishing chamber, completing the short circuit closing.

[0010] By adopting the above solution, the present invention abandons the design of the traditional independent operating mechanism of vacuum load switch, and drives the vacuum interrupter to operate through the integrated linkage of the three-position disconnecting switch operating mechanism, which simplifies the overall structure of the equipment and greatly reduces the manufacturing cost of the equipment.

[0011] This invention features a linkage transmission structure that strictly limits the operating sequence of the disconnecting switch and the vacuum interrupter, creating a closed-loop logic for closing, opening, and grounding operations. This completely eliminates misoperation and significantly improves equipment operating safety and power supply reliability.

[0012] It achieves arc extinguishing under all working conditions by relying on the vacuum interrupter chamber, without relying on the arc extinguishing performance of environmentally friendly gases such as dry air and nitrogen, and without the need to lengthen the arc expansion structure, effectively reducing the overall volume of the ring main unit, improving equipment integration, and adapting to standardized cabinet installation. Attached Figure Description

[0013] Figure 1 This is a schematic diagram (three-dimensional) of the overall assembly structure of the present invention; Figure 2 This is a schematic diagram (cross-section) of the overall assembly structure of the present invention. Figure 3 This is a schematic diagram of the linkage transmission structure of the present invention. Figure 2 (A enlarged view).

[0014] Label Explanation: 1. Three-position operating mechanism; 2. Three-position disconnecting switch; 21. Pulling rod; 22. Three-position disconnecting switch rotating shaft; 3. Vacuum load switch arc-extinguishing chamber; 31. Vacuum load switch arc-extinguishing chamber moving end; 4. Linkage transmission device; 41. "Y" shaped pulling fork; 42. Compression spring lifting rod; 43. Spring sleeve; 44. Compression spring; 5. Closing stationary contact; 6. Grounding stationary contact; 7. Insulating drive rod; 8. Switch cabinet; 9. Flexible connection. Detailed Implementation

[0015] To illustrate the technical content, structural features, objectives, and effects of the present invention in detail, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0016] like Figure 1 , Figure 2 As shown, the load switch of the environmentally friendly gas ring main unit of the present invention includes a three-position operating mechanism 1, a three-position disconnecting switch 2, a vacuum load switch arc-extinguishing chamber 3, and a linkage transmission device 4, which are assembled inside the environmentally friendly gas ring main unit 8. The cabinet is filled with dry air or nitrogen as an insulating medium. The three-position disconnecting switch 3 can be connected to the closing stationary contact 5, the grounding stationary contact 6, and the open state in the middle around the three-position disconnecting switch rotating shaft 22.

[0017] like Figure 3 As shown, a lever 21 is provided on the side of the rotating shaft 22 of the three-position disconnect switch. The lever 21 also rotates with the three-position disconnect switch 2. A linkage transmission device 4 is provided between the lever 21 and the arc-extinguishing chamber 3 of the vacuum load switch. The upper end of the arc-extinguishing chamber 3 of the vacuum load switch is the moving end 31 of the arc-extinguishing chamber of the vacuum load switch. The moving end 31 of the arc-extinguishing chamber of the vacuum load switch is electrically connected to the outgoing line through a flexible connection 9. The linkage transmission device 4 consists of a "Y"-shaped fork 41, a compression spring lifting rod 42, a spring sleeve 43, and a compression spring 44. The compression spring 44 inside the spring sleeve 43 is sleeved on the moving end 31 of the vacuum load switch arc-extinguishing chamber. The lower end of a rotatable "Y"-shaped fork 41 is movably hinged to the compression spring lifting rod 42. The lever 21, which is laterally arranged on the shaft 22 of the three-position disconnect switch, is inserted into the open fork end of the "Y"-shaped fork 41. When the three-position disconnect switch 2 rotates clockwise, the lever 21 drives the "Y"-shaped fork 41 to rotate counterclockwise. The compression spring lifting rod 42 pulls the compression spring lifting rod 42, thereby causing the moving end 31 of the vacuum load switch arc-extinguishing chamber to move upward. Conversely, when the lever 21 drives the "Y"-shaped fork 41 to rotate clockwise, the compression spring lifting rod 42 presses down, thereby causing the moving end 31 of the vacuum load switch arc-extinguishing chamber to move downward.

[0018] This equipment eliminates the traditional independent dedicated operating mechanism for vacuum load switches, using only a three-position operating mechanism 1 as the sole power source. The three-position operating mechanism 1 and the three-position disconnect switch 2 are connected via an insulated drive rod 7. Simultaneously, the three-position disconnect switch 2 is connected to the vacuum load switch arc-extinguishing chamber 3 via a linkage transmission device 4, enabling the three-position operating mechanism 1 to control both the three-position disconnect switch 2 and the vacuum load switch arc-extinguishing chamber 3 in a coordinated manner. This eliminates the need for a separate operating mechanism for the vacuum load switch arc-extinguishing chamber. The linkage transmission device 4 works in conjunction with both the three-position disconnect switch 2 and the vacuum load switch arc-extinguishing chamber 3 to achieve a forced locking of the operating sequence.

[0019] During the equipment closing operation, the three-position operating mechanism 1 drives the three-position disconnector 2 to switch from the open state to the closed state (the three-position disconnector 2 rotates counterclockwise). After the three-position disconnector 2 is fully closed, due to the short design of the lever 21 on the side of the three-position disconnector shaft 22, and considering the size of the gap of the "Y"-shaped lever 41, the vacuum load switch arc-extinguishing chamber 2 performs the closing action after the three-position disconnector 2 is closed. The closing of the three-position disconnector 2 will not generate an electric arc. The only arc generated by the vacuum arc-extinguishing chamber is the arc generated during the closing of the entire circuit. The arc generated at the moment of load connection is extinguished by the vacuum arc-extinguishing principle, thus completing the closing and power-on operation.

[0020] When the equipment is in the tripping operation, the three-position disconnector 2 rotates clockwise. Before it is disengaged from the closing stationary contact 5, the lever 21 pulls the "Y"-shaped lever 41 to rotate counterclockwise. Under the action of the compression spring 44, the moving end 31 of the vacuum load switch arc-extinguishing chamber moves upward. The arc-extinguishing chamber first performs the tripping action to extinguish the arc generated by the interruption of the load current. After the vacuum arc-extinguishing chamber is fully tripped, the "Y"-shaped lever 41 rotates counterclockwise and the lever 21 rotates clockwise. The "Y"-shaped lever 41 releases the lock on the lever 21 of the three-position disconnector (i.e., the lever 21 disengages from the forked part of the "Y"-shaped lever 41). Only then can the three-position disconnector 2 perform the full tripping action without generating a tripping arc.

[0021] During equipment grounding operations, the grounding switch (not shown in the figure) will complete the closing action first. This process will not generate an electric arc and will establish a grounding circuit. Subsequently, the mechanical interlock will unlock the vacuum load switch arc extinguishing chamber, and the arc extinguishing chamber will perform the closing action. If a short circuit occurs due to accidental closing to the power supply point, the vacuum load switch arc extinguishing chamber can quickly extinguish the short circuit closing arc, avoid the risk of equipment short circuit burnout, and ensure the safe operation of the equipment.

[0022] Traditional vacuum load switch operation involves first closing the disconnector switch via the three-position disconnector operating mechanism, and then closing the vacuum load switch via the vacuum load switch operating mechanism. This invention cleverly designs a lever 21 to move a "Y"-shaped lever 41 to achieve linkage between the three-position disconnector switch and the vacuum load switch. This not only eliminates the vacuum load switch operating mechanism but also the linkage device between the vacuum load switch operating mechanism and the three-position disconnector operating mechanism, achieving a leapfrog innovation. This invention has a simple structure, low cost, and reliable operation, perfectly solving the problems of large size, high cost, and cumbersome operation of traditional environmental protection ring main units.

[0023] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. An environmentally friendly gas ring main unit load switch, comprising a three-position disconnect switch, a three-position operating mechanism, and a vacuum load switch arc-extinguishing chamber, wherein the three-position operating mechanism is connected to the three-position disconnect switch via an insulated drive rod, characterized in that: A linkage transmission device is provided between the three-position disconnecting switch and the arc-extinguishing chamber of the vacuum load switch. When the three-position operating mechanism drives the three-position disconnecting switch to complete the switching of the opening, closing, and grounding positions, the linkage transmission device controls the arc-extinguishing chamber of the vacuum load switch to synchronously open and close.

2. The environmentally friendly gas ring main unit load switch as described in claim 1, characterized in that: The linkage transmission device includes a lever on the three-position disconnect switch and a "Y"-shaped lever fork that is linked to the moving end of the arc-extinguishing chamber of the vacuum load switch. The lever on the three-position disconnect switch is rotatably inserted into the upper fork of the "Y"-shaped lever fork, and the lower end of the "Y"-shaped lever fork is connected to the moving end of the arc-extinguishing chamber of the vacuum load switch via a spring.

3. The operation method of the load switch for the environmentally friendly gas ring main unit, characterized in that: A linkage transmission device is installed between the three-position disconnector and the arc-extinguishing chamber of the vacuum load switch. When the load switch of the environmental gas ring main unit is closed, the three-position disconnector changes from the open state to the closed state. The three-position operating mechanism synchronously operates the arc-extinguishing chamber of the vacuum load switch to close through the linkage transmission device and is responsible for extinguishing the arc generated by the closing and connection of the load switch of the environmental gas ring main unit. When the switch is opened, the three-position operating mechanism drives the arc-extinguishing chamber of the vacuum load switch to open first through the linkage transmission device, extinguishing the arc generated by the interruption of the load current. When grounding occurs, the grounding switch closes first, and the arc-extinguishing chamber of the vacuum load switch closes later. If the switch closes to the power supply point, the short circuit closing is formed, and the arc is extinguished by the vacuum arc-extinguishing chamber, completing the short circuit closing.

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