Load switch based on vacuum arc extinguishing

Abstract

The invention relates to the technical field of medium-voltage complete equipment, in particular to a load switch based on vacuum arc extinguishment, which comprises a disconnecting link assembly, a vacuum arc extinguish chamber and a vacuum arc extinguish chamber, and is characterized in that the disconnecting link assembly comprises a disconnecting link moving end and a disconnecting link static end, and the disconnecting link moving end is connected with or disconnected from the disconnecting link static end through driving of an external driving mechanism; the connection and disconnection of the disconnecting link moving end and the disconnecting link static end correspond to the connection and disconnection of a main loop; the vacuum arc-extinguishing chamber is electrically connected with the disconnecting link assembly in parallel; the vacuum arc-extinguishing chamber comprises a static contact and a moving contact, the static contact is connected with the static end of the disconnecting link, and the moving contact is connected with the transmission assembly. The disconnecting link assembly and the vacuum arc-extinguishing chamber are connected in parallel, so that current is transferred to a vacuum arc-extinguishing chamber branch at the initial opening stage, arc extinguishing is completed by utilizing the vacuum arc-extinguishing chamber, the situation that the disconnecting link directly breaks load current is avoided, and the vacuum arc-extinguishing chamber is driven to be opened after an enough safety gap is reached through the matching relation of the disconnecting link assembly and the transmission assembly. And electric arc reignition and breakdown risks caused by insufficient gaps are avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of medium-voltage complete equipment, and in particular to a load switch based on vacuum arc extinguishing. Background Art

[0002] In the field of medium- and high-voltage switchgear, sulfur hexafluoride (SF6) is widely used due to its excellent arc-extinguishing and insulating properties. However, SF6 is a potent greenhouse gas, with a greenhouse effect potential 23,500 times that of carbon dioxide and an atmospheric lifetime of up to 3,200 years, posing a serious threat to the ecological environment. Furthermore, SF6 produces a variety of toxic byproducts during arc decomposition, which not only pollute the atmosphere but also pose a health risk to on-site operators.

[0003] The technical solution of using vacuum as the arc-extinguishing medium, supplemented by environmentally friendly gas insulation, has significant environmental benefits and is becoming a key direction for the green transformation of medium- and high-voltage switchgear. During the tripping phase of a vacuum load switch, the active end of the switch moves away from the static end and contacts the transmission assembly, transferring the current to the vacuum interrupter branch, which then interrupts the current. However, during the current transfer phase, when the physical distance between the active and static ends of the switch does not meet safety requirements, the vacuum interrupter is driven to trip. The gap between the active and static ends of the switch is insufficient to withstand the recovery voltage, potentially causing a breakdown, leading to the arc reigniting between the active and static ends. Since the vacuum interrupter is already open, it cannot effectively extinguish the arc, causing a persistent arc, potentially damaging the equipment or even exploding, which can negatively impact the service life and performance stability of the switchgear. Summary of the Invention

[0004] (1) Purpose of the invention

[0005] The purpose of the present invention is to provide a load switch based on vacuum arc extinguishing, which realizes the current transfer to the vacuum arc chamber branch at the initial stage of opening by connecting the knife switch assembly in parallel with the vacuum arc chamber, utilizes the vacuum arc chamber to complete the arc extinguishing, avoids the knife switch directly disconnecting the load current, improves the disconnection reliability and safety, reduces the contact arc erosion, and extends the service life.

[0006] (2) Technical solution

[0007] In order to solve the above problems, the present invention provides a load switch based on vacuum arc extinguishing, which is used to connect and disconnect the main circuit. The load switch includes: a knife switch assembly, a vacuum arc extinguishing chamber and a transmission assembly;

[0008] The knife switch assembly includes a knife switch dynamic end and a knife switch static end. The knife switch dynamic end is driven by an external driving mechanism to engage or disengage with the knife switch static end. The engagement and disengagement of the knife switch dynamic end and the knife switch static end correspond to the connection and disconnection of the main circuit.

[0009] The vacuum interrupter is electrically connected in parallel with the knife switch assembly;

[0010] The vacuum interrupter includes a static contact and a moving contact, wherein the static contact is connected to the static end of the knife switch, and the moving contact is connected to the transmission assembly;

[0011] During the opening process of the movable end and the static end of the knife switch, in a first state, the movable end of the knife switch is spaced a first distance from the transmission assembly, the knife switch assembly, the vacuum interrupter and the transmission assembly form a vacuum interrupter branch, and the current is transferred from the main circuit to the vacuum interrupter branch; in a second state, the movable end of the knife switch is spaced a second distance from the static end of the knife switch, the static contact and the movable contact are separated, the current is cut off and the opening is completed;

[0012] During the closing process of the knife switch moving end and the knife switch static end, the knife switch moving end engages the static contact and the moving contact through the transmission assembly, and the knife switch moving end engages with the knife switch static end to complete the closing.

[0013] In another aspect of the present invention, preferably, the transmission assembly includes a first connecting rod, a second connecting rod and a transmission component;

[0014] One end of the first connecting rod is pivotally connected to the housing of the vacuum interrupter, the other end of the first connecting rod is movably connected to one end of the second connecting rod, the middle position of the first connecting rod is pivotally connected to the moving contact, and the other end of the second connecting rod is pivotally connected to the transmission component;

[0015] When the switch is opened, the movable end of the knife switch drives the transmission component to move, thereby driving the first connecting rod and the second connecting rod to move;

[0016] In the first state, the second connecting rod rotates relative to the first connecting rod to form an idle stroke. In the second state, the second connecting rod rotates synchronously with the first connecting rod to drive the static contact and the moving contact to separate.

[0017] In another aspect of the present invention, preferably, a concave structure is provided at the other end of the first connecting rod, and a convex structure is provided at one end of the second connecting rod, and the concave structure is adapted to the convex structure. In the first state, the second connecting rod rotates relative to the first connecting rod to form an idle stroke. In the second state, the outer side surface of the convex structure contacts the inner side surface of the concave structure, and the second connecting rod rotates synchronously with the first connecting rod to drive the static contact and the moving contact to disengage.

[0018] In another aspect of the present invention, preferably, the transmission component includes a third connecting rod and a rotating member;

[0019] The rotating member is configured as a U-shaped structure, one end of the third connecting rod is connected to the other end of the second connecting rod, the other end of the third connecting rod is connected to one end of the U-shaped structure of the rotating member, the bottom of the U-shaped structure of the rotating member is pivotally connected to the outside, and the moving end of the knife gate drives the transmission assembly to move by driving the side of the U-shaped structure to move.

[0020] In another aspect of the present invention, preferably, the U-shaped structure of the rotating member includes a first side and a second side, the first side is a conductive side, and the second side is an insulating side;

[0021] When the switch is open, the movable end of the knife switch contacts the first side edge, and when the switch is closed, the movable end of the knife switch contacts the second side edge.

[0022] In another aspect of the present invention, preferably, the vacuum interrupter further comprises a moving end guide rod, the moving end guide rod is arranged between the moving contact and the first connecting rod, the moving contact is fixedly connected to the moving end guide rod, and the first connecting rod is movably connected to the moving end guide rod.

[0023] Another aspect of the present invention preferably further includes: a compression spring and a guide rod, wherein the two ends of the compression spring are respectively connected to the first connecting rod and the shell of the vacuum arc chamber, the compression spring is sleeved on the guide rod, one end of the guide rod is connected to the first connecting rod, and the other end is a free end.

[0024] Another aspect of the present invention preferably further includes: a torsion spring, which is arranged at the connection between the first connecting rod and the second connecting rod, and the torsion spring is used to provide a reset force to the second connecting rod after the opening or closing of the switch is completed, so as to drive the second connecting rod to reset relative to the first connecting rod.

[0025] Another aspect of the present invention preferably further includes: a tension spring; the two ends of the tension spring are respectively connected to the shell and the second side of the vacuum interrupter, and are used to give the first side a force to contact the moving end of the knife switch in the first state when the switch is opened.

[0026] In another aspect of the present invention, preferably, it further comprises: a limiting member, wherein the limiting member is provided on the housing of the vacuum interrupter, and the rotating member is subjected to the tension of the tension spring and abuts against the limiting member in the open state.

[0027] (3) Beneficial effects

[0028] The above technical solution of the present invention has the following beneficial technical effects:

[0029] The present invention connects the knife switch assembly in parallel with the vacuum interrupter, so that the current is transferred to the vacuum interrupter branch at the initial stage of opening, and the vacuum interrupter is used to extinguish the arc, avoiding the knife switch directly interrupting the load current. Through the cooperation relationship between the knife switch assembly and the transmission assembly, it is ensured that the vacuum interrupter is driven to open only after the current reaches a sufficient safety gap between the moving end and the static end of the knife switch, avoiding the risk of arc reignition and breakdown caused by insufficient gap, improving the disconnection reliability and safety, reducing contact arc erosion, and extending the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of the overall structure of a load switch according to an embodiment of the present invention;

[0031] Figure 2 This is a schematic diagram of the current transfer stage during the opening process of a load switch according to an embodiment of the present invention;

[0032] Figure 3 This is a schematic diagram of the idle stroke stage during the opening process of a load switch according to an embodiment of the present invention;

[0033] Figure 4 Schematic diagram of the vacuum interrupter starting to open during the load switch opening process according to an embodiment of the present invention;

[0034] Figure 5 This is a schematic diagram of the separation of the movable end of the knife switch and the transmission assembly during the opening process of the load switch according to an embodiment of the present invention;

[0035] Figure 6 This is a schematic diagram of a transmission component at a dead point during the opening process of a load switch according to an embodiment of the present invention;

[0036] Figure 7 This is a schematic diagram of a load switch in an open state according to an embodiment of the present invention;

[0037] Figure 8 This is a schematic diagram of the contact between the movable end of the knife switch and the transmission assembly during the closing process of the load switch according to an embodiment of the present invention;

[0038] Figure 9 Schematic diagram of a transmission component at a dead point during a load switch closing process according to an embodiment of the present invention;

[0039] Figure 10 Schematic diagram of the contact between the moving end of the knife switch and the static end of the knife switch during the closing process of the load switch according to an embodiment of the present invention;

[0040] Figure 11 1. It is a schematic diagram of the vacuum interrupter closing process during the load switch closing process according to an embodiment of the present invention;

[0041] Reference numerals:

[0042] 1. Knife switch assembly, 11. Knife switch moving end, 12. Knife switch static end, 2. Vacuum interrupter, 21. Static contact, 22. Moving contact, 23. Moving end guide rod, 24. Housing, 3. Transmission assembly, 31. First connecting rod, 32. Second connecting rod, 33. Third connecting rod, 34. Rotating part, 341. First side, 342. Second side, 4. Compression spring, 5. Torsion spring, 6. Tension spring, 7. Limiting part, a. Opening rotation direction of the moving end of the knife switch, b. Closing rotation direction of the moving end of the knife switch. DETAILED DESCRIPTION

[0043] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present invention.

[0044] The accompanying drawings illustrate schematic diagrams of structures according to embodiments of the present invention. These figures are not drawn to scale; for clarity, some details are exaggerated and some details may be omitted. The shapes of the various regions and layers shown in the figures, as well as their relative sizes and positions, are merely exemplary and may deviate in practice due to manufacturing tolerances or technical limitations. Those skilled in the art may design regions / layers with different shapes, sizes, and relative positions as needed.

[0045] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0046] In the description of the present invention, it should be noted that the terms "first", "second" and "third" are only used for descriptive purposes and should not be understood as indicating or implying relative importance.

[0047] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0048] The present invention will be described in more detail below with reference to the accompanying drawings. In each of the accompanying drawings, identical elements are represented by similar reference numerals. For the sake of clarity, the various parts in the accompanying drawings are not drawn to scale.

[0049] Example 1

[0050] A load switch based on vacuum arc extinguishing, Figure 1 FIG. 1 shows a schematic diagram of the overall structure of a load switch according to an embodiment of the present invention. Figure 1As shown, the load switch is used to connect and disconnect the main circuit. The load switch includes: a knife switch assembly 1, a vacuum interrupter 2 and a transmission assembly 3;

[0051] The knife switch assembly 1 includes a knife switch dynamic end 11 and a knife switch static end 12. The knife switch dynamic end 11 is driven by an external driving mechanism to engage or disengage with the knife switch static end 12. The engagement and disengagement of the knife switch dynamic end and the knife switch static end correspond to the connection and disconnection of the main circuit. The knife switch static end 12 is fixedly installed to the casing and is electrically connected to the busbar.

[0052] The vacuum interrupter 2 is electrically connected in parallel with the knife switch assembly 1;

[0053] The static end of the vacuum interrupter 2 is electrically connected to the busbar. The vacuum interrupter 2 includes a static contact 21 and a moving contact 22. The static contact 21 is connected to the static end 12 of the knife switch, and the moving contact 22 is connected to the transmission assembly 3. The vacuum interrupter 2 also includes a moving end guide rod 23. The moving end guide rod 23 is arranged between the moving contact 22 and the first connecting rod 31. The moving contact 22 is fixedly connected to the moving end guide rod 23, and the first connecting rod 31 is movably connected to the moving end guide rod 23.

[0054] During the opening process of the knife switch movable end 11 and the knife switch static end 12, in the first state, the knife switch movable end 11 is separated from the transmission assembly 3 by a first distance. The knife switch assembly 1, the vacuum interrupter 2, and the transmission assembly 3 form a vacuum interrupter branch, and the current is transferred from the main circuit to the vacuum interrupter branch. In the second state, the knife switch movable end 11 is separated from the knife switch static end 12 by a second distance. The static contact 21 and the movable contact 22 are disengaged, cutting off the current and completing the opening process. During the opening process, the knife switch movable end 11 gradually moves away from the knife switch static end 12 under the action of the external drive mechanism. At this stage, the transmission assembly 3 is in the first state, the vacuum interrupter 2 and the knife switch assembly 1 form a parallel branch, and the current is smoothly transferred from the main circuit to the vacuum interrupter branch, preventing the knife switch contacts from directly bearing the arc pressure of the breaking current. When the physical gap between the moving and static terminals 11 and 12 of the switch increases to a level sufficient to withstand the recovery voltage, the transmission assembly 3 switches to the second state, driving the moving contact 22 and static contact 21 in the vacuum interrupter 2 to separate, effectively interrupting the current. Because the opening operation is performed within the electrical safety clearance, the risk of gap breakdown and arc reignition is avoided, ensuring the safety and stability of the opening operation.

[0055] During the closing process of the knife switch moving end 11 and the knife switch static end 12, the knife switch moving end 11 engages the static contact 21 and the moving contact 22 through the transmission assembly 3, and the knife switch moving end 11 engages with the knife switch static end 12 to complete the closing.

[0056] This embodiment uses vacuum as the arc-extinguishing medium, supplemented by environmentally friendly gas as the insulating medium, replacing traditional sulfur hexafluoride (SF6) gas. This not only avoids the greenhouse effect caused by SF6 on the environment, but also simplifies the sealing and recycling process of the switch cabinet, reduces the production and maintenance costs of the equipment, and meets the trend of green development of medium and high voltage power distribution equipment. By connecting the knife switch assembly in parallel with the vacuum interrupter, the current is transferred to the vacuum interrupter branch at the initial stage of opening, and the vacuum interrupter is used to extinguish the arc, avoiding the knife switch directly interrupting the load current. The coordination between the knife switch assembly and the transmission assembly ensures that the current only drives the vacuum interrupter to open after reaching a sufficient safety gap between the moving end and the static end of the knife switch, thereby cutting off the current and achieving environmentally friendly insulation without sulfur hexafluoride, while also improving the service life and reliability of the switch equipment.

[0057] Furthermore, in this embodiment, the transmission assembly 3 includes a first connecting rod 31, a second connecting rod 32 and a transmission component; through the cooperation of the multi-link structure, the idle stroke of the transmission assembly is realized in the current transfer stage, and the vacuum interrupter is driven to open only when the safe distance between the moving end of the knife switch and the static end of the knife switch is reached, thereby ensuring the reliability of the load switch disconnection.

[0058] One end of the first connecting rod 31 is pivotally connected to the housing 24 of the vacuum interrupter 2. The first connecting rod 31 rotates about a fixed rotation axis, and the other end of the first connecting rod 31 is movably connected to one end of the second connecting rod. The middle portion of the first connecting rod 31 is pivotally connected to the moving contact 22, and the other end of the second connecting rod is pivotally connected to the transmission component. One end of the first connecting rod 31 is pivotally connected to the housing 24 of the vacuum interrupter 2 and can rotate about a fixed rotation axis, while the other end is connected to one end of the second connecting rod 32 via a movably hinged connection. Simultaneously, the middle portion of the first connecting rod 31 is pivotally connected to the moving contact 22 of the vacuum interrupter, thereby directly driving the moving contact 22 to open and close when the transmission assembly is actuated. The other end of the second connecting rod 32 is pivotally connected to the transmission component, which in turn operates in conjunction with the knife switch moving end 11 to achieve coordinated movement of the knife switch assembly and the vacuum interrupter.

[0059] During opening, the movable end 11 of the switch drives the transmission component, thereby driving the first and second connecting rods 31 and 32. In the first state, the second connecting rod 32 rotates relative to the first connecting rod 31, creating an idle stroke. In the second state, the second connecting rod 32 rotates synchronously with the first connecting rod 31, driving the static and moving contacts 21 and 22 apart. The external drive mechanism drives the movable end 11, which in turn drives the second and first connecting rods 32 and 31 through the transmission component. In the initial opening phase, as the movable end 11 begins to separate from the static end 12, the second connecting rod 32 rotates relative to the first connecting rod 31, creating an idle stroke. During this phase, the movable contact 22 of the vacuum interrupter remains closed. As the movable end 11 continues to move away from the static end 12, and the physical gap between them increases to a sufficient level to withstand the recovery voltage, the second connecting rod 32 and the first connecting rod 31 transition from relative rotation to synchronous rotation. During this process, the second connecting rod 32 forms a rigid fit with the first connecting rod 31, driving the first connecting rod 31 to rotate synchronously, and then driving the vacuum interrupter moving contact 22 and the static contact 21 to separate, cutting off the vacuum interrupter branch current and completing the opening operation.

[0060] This embodiment realizes a two-stage action of the opening process: the first stage is the first state is the idle stroke stage, which ensures that the vacuum interrupter remains in a closed state during the current transfer, thereby avoiding the risk of arc reignition caused by insufficient knife switch gap; the second stage is the second state is the synchronous drive stage, which ensures that the opening action of the vacuum interrupter is performed only after the knife switch moving end 11 and the knife switch static end 12 reach a safe gap, thereby achieving the safety and reliability of the breaking action.

[0061] Furthermore, to achieve idle travel of the transmission assembly during the tripping process and ensure accurate driving of the vacuum interrupter to trip after reaching the safety gap, a concave-convex matching structure is adopted between the first connecting rod 31 and the second connecting rod 32. The other end of the first connecting rod 31 is provided with a concave structure, and one end of the second connecting rod is provided with a convex structure. The concave structure is adapted to the convex structure. In the first state, the second connecting rod 32 can rotate relative to the first connecting rod 31 to form an idle travel. In the second state, the outer side surface of the convex structure contacts the inner side surface of the concave structure, causing the second connecting rod 32 to rotate synchronously with the first connecting rod 31, driving the static contact 21 and the moving contact 22 to disengage. The other end of the first connecting rod 31 is provided with a concave structure. The concave structure is U-shaped or arc-shaped, and its inner surface serves as a contact surface for mating with the convex structure of the second connecting rod 32. One end of the second connecting rod 32 is provided with a convex structure that matches the concave structure. The convex structure can be cylindrical, wedge-shaped, or spherical. Its outer surface serves as a contact surface for abutting the inner surface of the concave structure during the later stages of the opening process. This geometric matching of the concave and convex structures enables the two connecting rods to achieve two different operating states at different stages of the opening process.

[0062] In the initial opening phase (the first state), the movable end 11 of the knife switch begins to separate from the static end 12, and the external drive mechanism drives the second connecting rod 32 through the transmission component. During this phase, the convex structure is located within the gap between the concave structure, but there is no contact between the two, maintaining only a clearance fit, allowing the second connecting rod 32 to rotate freely relative to the first connecting rod 31. At this time, the first connecting rod 31 is not driven to rotate, and the movable contact 22 of the vacuum interrupter remains closed to the static contact 21. Current continues to flow through the vacuum interrupter branch, avoiding the risk of insufficient knife switch contact gap and arc reignition due to premature opening of the vacuum interrupter, thereby achieving idle travel.

[0063] In the later stage of opening (the second state), when the movable end 11 of the knife switch continues to move away from the static end 12 of the knife switch, the physical gap between the two gradually increases. When it reaches a safe distance, the transmission component continues to drive the second connecting rod 32 to rotate, and the convex structure gradually contacts the inner side surface of the concave structure. At this time, the second state is entered, and the outer side surface of the convex structure and the inner side surface of the concave structure are in surface or point contact, forming a rigid transmission connection. The second connecting rod 32 and the first connecting rod 31 no longer rotate relative to each other, but rotate synchronously. As the first connecting rod 31 rotates synchronously, its pivot connection point with the moving contact 22 of the vacuum interrupter is driven, so that the moving contact 22 is separated from the static contact 21, completing the opening action of the vacuum interrupter and successfully cutting off the current. Through the design of the above-mentioned concave and convex structure, this embodiment realizes the action of first idling and then rigid transmission during the opening process.

[0064] Furthermore, in this embodiment, the transmission component includes a third connecting rod 33 and a rotating member 34;

[0065] The rotating member 34 is configured as a U-shaped structure, one end of the third connecting rod 33 is connected to the other end of the second connecting rod 32, the other end of the third connecting rod 33 is connected to one end of the U-shaped structure of the rotating member 34, the bottom of the U-shaped structure of the rotating member 34 is pivotally connected to the outside, and the moving end 11 of the knife switch drives the transmission assembly 3 to move by driving the side of the U-shaped structure.

[0066] The U-shaped structure of the rotating member 34 includes a first side 341 and a second side 342, the first side 341 is a conductive side, and the second side 342 is an insulating side; the rotating member 34 adopts a U-shaped structure design to achieve stable mechanical transmission between the movable end 11 of the knife switch and the transmission assembly 3, and by distinguishing between the conductive and insulating parts, the functional separation of the opening and closing operations is achieved, thereby ensuring the safety and reliability of the load switch under different working conditions.

[0067] When the switch is open, the movable end 11 of the knife switch contacts the first side 341 , and when the switch is closed, the movable end 11 of the knife switch contacts the second side 342 .

[0068] One end of the third connecting rod 33 is connected to the other end of the second connecting rod 32 by a hinged connection, and the other end is connected to one end of the U-shaped structure of the rotating member 34, so that the rotation of the rotating member 34 can be transmitted to the second connecting rod 32 and the first connecting rod 31, and finally the opening and closing operation of the vacuum interrupter 2 is realized. The bottom of the U-shaped structure of the rotating member 34 is fixed to the support component of the switch cabinet by a pivoting manner, so that it can rotate around a fixed rotation axis. The movable end 11 of the knife switch contacts the U-shaped structure of the rotating member 34 under the action of the external driving mechanism, and drives the rotating member 34 to rotate by pushing the side of the U-shaped structure, and then drives the second connecting rod 32 to move through the third connecting rod 33, realizing the opening and closing linkage of the vacuum interrupter.

[0069] Furthermore, this embodiment further includes a compression spring 4 and a guide rod. The two ends of the compression spring 4 respectively connect the first connecting rod 31 and the housing 24 of the vacuum interrupter 2. The compression spring 4 is mounted on the guide rod, with one end of the guide rod connected to the first connecting rod 31 and the other end being free. The compression spring 4 is used to provide stable support and cushioning for the first connecting rod 31 during the opening and closing process. The two ends of the compression spring 4 are respectively connected to the first connecting rod 31 and the housing 24 of the vacuum interrupter 2, and are mounted on the guide rod. One end of the guide rod is fixedly connected to the first connecting rod 31, and the other end is free. Through the guide rod, the compression spring 4 can apply a moderate elastic force to the first connecting rod 31 during the opening and closing process, ensuring smooth operation of the first connecting rod 31 during operation and avoiding structural stress concentration caused by inertial impact. At the same time, it provides a reset force after the operation is completed, helping the first connecting rod 31 return to its initial position, thereby improving the mechanical durability of the transmission assembly.

[0070] Furthermore, in this embodiment, it also includes: a torsion spring 5, which is arranged at the connection between the first connecting rod 31 and the second connecting rod 32. The torsion spring 5 is used to provide a reset force to the second connecting rod 32 after the opening or closing of the switch is completed, so as to drive the second connecting rod 32 to reset relative to the first connecting rod 31.

[0071] Furthermore, in this embodiment, it also includes: a tension spring 6; the two ends of the tension spring 6 are respectively connected to the shell 24 and the second side 342 of the vacuum interrupter 2, and are used to provide a force for the first side 341 to contact the knife switch movable end 11 in the first state when the switch is opened. During the opening process, when the knife switch movable end 11 contacts the first side 341 of the rotating part 34 and is in the first state, a stable pulling force is provided to the rotating part 34 to ensure that the first side 341 and the knife switch movable end 11 remain in contact, thereby avoiding contact failure caused by vibration or position deviation during the opening process. At the same time, the tension spring 6 can also assist the rotating part 34 to return to its initial position after the opening is completed, thereby improving the reset accuracy and reliability of the device.

[0072] Furthermore, this embodiment further includes a stopper 7, which is disposed on the housing 24 of the vacuum interrupter 2. In the open state, the rotating member 34 is subjected to the tension of the tension spring 6 and abuts against the stopper 7. The stopper 7, disposed on the housing 24 of the vacuum interrupter 2, is used to mechanically limit the open limit position of the rotating member 34. When the rotating member 34 is pulled by the tension spring 6 during the opening process, the rotating member 34 contacts the stopper 7, thereby preventing the rotating member 34 from excessive rotation due to inertia, which could cause dislocation or damage to the connecting rod mechanism.

[0073] The opening and closing process of the load switch based on vacuum arc extinguishing in the present invention is as follows:

[0074] like Figure 1 As shown, when the load switch is closed, the knife switch movable terminal 11 is stationary relative to the knife switch static terminal 12 and is engaged with the knife switch static terminal 12, and the knife switch main circuit is conductive. The vacuum interrupter movable contact 22 and static contact 21 are engaged, while the knife switch movable terminal 11 is not engaged with the transmission assembly 3, and the vacuum interrupter branch circuit is not conductive.

[0075] Figure 2 FIG. 1 shows a schematic diagram of the current transfer phase during the opening process of a load switch according to an embodiment of the present invention; FIG. Figure 2 As shown, the load switch starts to open, and the knife switch movable end 11 starts to rotate around the pivot axis in the first direction shown by arrow a, and gradually separates from the knife switch static end 12. When the knife switch movable end 11 rotates to contact the first side 341 of the rotating member of the transmission assembly 3 and the knife switch static end 12 at the same time, that is, Figure 2 At the position shown, the knife switch moving end 11 and the knife switch static end 12 are still in the engaged state, and the knife switch main circuit is turned on. At the same time, the vacuum interrupter branch is also turned on and starts to transfer current.

[0076] Figure 3 FIG. 1 shows a schematic diagram of an idle stroke phase of a load switch opening process according to an embodiment of the present invention. Figure 3As shown, the movable end 11 of the knife switch continues to rotate in the first direction indicated by arrow a until it disengages from the static end 12 of the knife switch. Simultaneously, it drives the side of the first side 341 of the rotating member of the engaging transmission assembly 3, pushing the rotating member 34 to rotate clockwise about the fixed rotation axis. Because the tension spring 6 has not yet exceeded its equilibrium position, the tension applied by the tension spring 6 on the rotating member 34 during the clockwise rotation of the rotating member 34 hinders the rotating member's clockwise rotation, ensuring reliable contact between the movable end 11 and the first side 341 and preventing any false contact. After the movable end 11 of the knife switch disengages from the static end 12 of the knife switch, it remains engaged with the first side 341 of the rotating member of the transmission assembly 3, and all current is transferred to the vacuum interrupter branch. As the movable end 11 pushes the rotating member 34, the rotating member 34 drives the third connecting rod 33 to the left, driving the second connecting rod 32 clockwise about the first connecting rod 31. During this process, the first connecting rod 31 does not move, and the vacuum interrupter 2 remains closed.

[0077] Figure 4 FIG. 1 is a schematic diagram of the vacuum interrupter starting to open during the load switch opening process according to an embodiment of the present invention; FIG. Figure 4 As shown, the knife switch moving end 11 continues to push the rotating member 34 to rotate, driving the second connecting rod 32 to continue to rotate clockwise. When the knife switch moving end 11 and the knife switch static end 12 meet the safety distance, the left inclined surface of the convex structure of the second connecting rod 32 contacts the left inclined surface of the concave structure of the first connecting rod 31. The second connecting rod 32 and the first connecting rod 31 rotate clockwise around the fixed rotation axis together, pulling down the guide rod 23 of the vacuum interrupter moving end. The vacuum interrupter 2 begins to open and form a vacuum arc. Because the separation of the vacuum interrupter moving contact 22 and the static contact 21 is delayed compared to the separation of the knife switch moving end 11 and the knife switch static end 12, and at the same time, the knife switch moving end 11 and the knife switch static end 12 reach a safe distance, it is ensured that the vacuum interrupter 2 completes the current interruption.

[0078] Figure 5 FIG1 shows a schematic diagram of the separation of the movable end of the knife switch and the transmission assembly during the opening process of the load switch according to an embodiment of the present invention; Figure 5 As shown, the movable end 11 of the knife switch continues to rotate in the first direction indicated by arrow a, and is separated from the transmission assembly 3. During this process, the tension spring 6 exceeds its equilibrium position, and the pulling force on the rotating member 34 is converted from resistance to power. The transmission assembly rotating member 34 continues to rotate clockwise under the action of the tension spring 6.

[0079] Figure 6 FIG1 shows a schematic diagram of a transmission assembly at a dead point during a load switch opening process according to an embodiment of the present invention; FIG1 shows a schematic diagram of a load switch at a dead point during a load switch opening process according to an embodiment of the present invention; Figure 6 As shown, the transmission assembly 3 is in a dead point position, that is, the connection point between the second connecting rod 32 and the third connecting rod 33, the connection point between the third connecting rod 33 and the first side 341 of the rotating member, and the fixed rotation point 8 of the rotating member 34 are on the same straight line. At this time, the vacuum interrupter 2 reaches the maximum opening distance.

[0080] Figure 7 FIG. 1 shows a schematic diagram of a load switch in an open state according to an embodiment of the present invention; FIG. Figure 7 As shown, under the action of the tension spring 6, the rotating member 34 continues to rotate past its dead center position and contacts the stopper 7. At this point, the vacuum interrupter 2 reaches the specified opening distance, and the rotating member 34 stops rotating, and the vacuum interrupter 2 remains in the open state. Simultaneously, the movable end 11 of the knife switch continues to rotate in the first direction indicated by arrow a to the open position, completing the tripping of the load switch. At this point, there is no mechanical or electrical connection between the movable end 11, the static end 12, and the transmission assembly 3.

[0081] Figure 8 FIG. 1 shows a schematic diagram of the contact between the movable end of the knife switch and the transmission assembly during the closing process of the load switch according to an embodiment of the present invention. Figure 8 As shown, the load switch begins to close, and the movable end 11 of the knife switch begins to rotate around the pivot axis in the second direction indicated by arrow b until it contacts the second side 342 of the rotating member of the transmission assembly 3, driving the second side 342 to rotate counterclockwise around the fixed rotation axis. At this time, the second side 342 drives the third connecting rod 33 to the left, driving the first connecting rod 31 to rotate clockwise around the fixed rotation axis, and the guide rod 23 of the movable end of the vacuum interrupter moves downward, increasing the opening distance of the vacuum interrupter contacts. Because the second side 342 is fixedly connected to the first side 341, the movable end 11 of the knife switch does not contact the first side 341 during the closing rotation process, and there is no electrical connection between the movable end 11 of the knife switch and the transmission assembly 3.

[0082] Figure 9 FIG. 1 shows a schematic diagram of a transmission component at a dead point during a load switch closing process according to an embodiment of the present invention; FIG. Figure 9 As shown, the movable end 11 of the knife switch continues to rotate in the second direction indicated by arrow b, driving the transmission assembly 3 to its dead center position, and the vacuum interrupter 2 reaches its maximum opening distance. At this time, the tension spring 6 has not yet exceeded its equilibrium position, hindering the counterclockwise rotation of the rotating member 34. The movable end 11 of the knife switch is in close contact with the rotating member 34. After the transmission assembly 3 passes the dead center, the movable end 11 of the knife switch continues to rotate in the second direction, disengaging from the second side 342 of the rotating member of the transmission assembly 3.

[0083] Figure 10 FIG. 1 shows a schematic diagram of the contact between the movable end of the switch and the static end of the switch during the closing process of a load switch according to an embodiment of the present invention. Figure 10As shown, the knife switch moving end 11 continues to rotate in the second direction until it re-engages with the knife switch static end 12, and the knife switch main circuit is turned on. After the knife switch moving end 11 is separated from the transmission assembly rotating member 34, the transmission assembly 3 has passed the dead point position, and at the same time, the tension spring 6 has also passed its equilibrium position, pulling the rotating member 34 to continue to rotate counterclockwise. Under the action of the torsion spring 5 and the pull of the third connecting rod 33, the second connecting rod 32 rotates counterclockwise until the right inclined surface of its convex structure contacts the right inclined surface of the concave structure of the first connecting rod 31. Under the self-closing force of the vacuum interrupter 2, the action of the compression spring 4 and the pull of the second connecting rod 32, the first connecting rod 31 rotates counterclockwise around the fixed rotating axis, pushing the vacuum interrupter moving end guide rod 23 upward, and the vacuum interrupter contact opening distance gradually decreases.

[0084] Figure 11 FIG. 1 shows a schematic diagram of vacuum interrupter closing during the load switch closing process according to an embodiment of the present invention. Figure 11 As shown, the transmission assembly rotating member 34 continues to rotate counterclockwise until the vacuum interrupter moving contact 22 is engaged with the static contact 21, and at the same time, the knife switch moving end 11 reaches its closing position, and the load switch is closed.

[0085] This embodiment adopts a technical solution of connecting the knife switch and the vacuum interrupter in parallel to achieve environmentally friendly insulation without sulfur hexafluoride, while improving the service life and reliability of the switchgear, in line with the needs of sustainable development. Through the structural design of the connecting rod of the transmission assembly, the reliable transfer of current from the knife switch circuit to the vacuum interrupter branch and the idle stroke of the transmission assembly are achieved during the opening process, ensuring that the current is cut off by the vacuum interrupter and the reliability of the opening. By combining the dead point position of the transmission assembly with the tension spring, the self-holding of the vacuum interrupter in the opening state is achieved, reducing the failure rate of the load switch operation. When closing the load switch, the knife switch is closed first and then the vacuum interrupter, avoiding the risk of failure to close the vacuum interrupter and ensuring the accuracy and safety of the closing operation. Through the matching structure between the connecting rods, the idle stroke control is achieved to ensure that the vacuum interrupter is opened again after the moving and static ends of the knife switch reach a safe opening distance, effectively avoiding the risk of recovery voltage breakdown and improving the electrical reliability and operational safety of the switch.

[0086] It should be understood that the above-described specific embodiments of the present invention are merely illustrative or illustrative of the principles of the present invention and do not constitute limitations of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included within the scope of protection of the present invention. In addition, the appended claims are intended to cover all variations and modifications that fall within the scope and metes and bounds of the appended claims, or equivalents thereof.

[0087] While the above description does not provide detailed technical details regarding patterning and etching of each layer, those skilled in the art will appreciate that various conventional methods can be used to form layers, regions, and the like in desired shapes. Furthermore, those skilled in the art may devise methods that differ from those described above to achieve the same structure.

[0088] The present invention has been described above with reference to the embodiments thereof. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. The scope of the present invention is defined by the appended claims and their equivalents. Those skilled in the art may make various substitutions and modifications without departing from the scope of the present invention, and such substitutions and modifications are intended to fall within the scope of the present invention.

[0089] Although the embodiments of the present invention have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.

[0090] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A load switch based on vacuum arc extinguishing, characterized in that: The load switch is used for connecting and disconnecting the main circuit, and comprises: a knife switch assembly (1), a vacuum interrupter (2) and a transmission assembly (3); The knife switch assembly (1) comprises a knife switch movable end (11) and a knife switch static end (12); the knife switch movable end (11) is driven by an external driving mechanism to engage with or disengage from the knife switch static end (12); the engagement and disengagement of the knife switch movable end (11) and the knife switch static end (12) correspond to the connection and disconnection of the main circuit; The vacuum interrupter (2) is electrically connected in parallel with the knife switch assembly (1); The vacuum interrupter (2) comprises a static contact (21) and a moving contact (22), wherein the static contact (21) is connected to the static end (12) of the knife switch, and the moving contact (22) is connected to the transmission assembly (3); During the opening process of the knife switch moving end (11) and the knife switch static end (12), in a first state, the knife switch moving end (11) and the transmission assembly (3) are spaced apart by a first distance, the knife switch assembly (1), the vacuum interrupter (2) and the transmission assembly (3) form a vacuum interrupter branch, and the current is transferred from the main circuit to the vacuum interrupter branch; in a second state, the knife switch moving end (11) and the knife switch static end (12) are spaced apart by a second distance, the static contact (21) and the moving contact (22) are separated, and the current is cut off to complete the opening; During the closing process of the knife switch moving end (11) and the knife switch static end (12), the knife switch moving end (11) enables the static contact (21) and the moving contact (22) to engage through the transmission component (3), and the knife switch moving end (11) engages with the knife switch static end (12), completing the closing process.

2. The load switch based on vacuum arc extinguishing according to claim 1, characterized in that: The transmission assembly (3) comprises a first connecting rod (31), a second connecting rod (32) and a transmission component; One end of the first connecting rod (31) is pivotally connected to the housing (24) of the vacuum interrupter (2), the other end of the first connecting rod (31) is movably connected to one end of the second connecting rod (32), the middle position of the first connecting rod (31) is pivotally connected to the moving contact (22), and the other end of the second connecting rod (32) is pivotally connected to the transmission component; When the switch is opened, the movable end (11) of the knife switch drives the transmission component to move, thereby driving the first connecting rod (31) and the second connecting rod (32) to move; In the first state, the second connecting rod (32) rotates relative to the first connecting rod (31) to form an idle stroke. In the second state, the second connecting rod (32) rotates synchronously with the first connecting rod (31) to drive the static contact (21) and the moving contact (22) to disengage.

3. The load switch based on vacuum arc extinguishing according to claim 2, characterized in that: The other end of the first connecting rod (31) is provided with a concave structure, and one end of the second connecting rod (32) is provided with a convex structure, and the concave structure is adapted to the convex structure. In the first state, the second connecting rod (32) rotates relative to the first connecting rod (31) to form an idle stroke. In the second state, the outer side surface of the convex structure contacts the inner side surface of the concave structure, and the second connecting rod (32) rotates synchronously with the first connecting rod (31), driving the static contact (21) and the moving contact (22) to disengage.

4. The load switch based on vacuum arc extinguishing according to claim 2, characterized in that: The transmission component includes a third connecting rod (33) and a rotating member (34); The rotating member (34) is configured as a U-shaped structure, one end of the third connecting rod (33) is connected to the other end of the second connecting rod (32), the other end of the third connecting rod (33) is connected to one end of the U-shaped structure of the rotating member (34), the bottom of the U-shaped structure of the rotating member (34) is pivotally connected to the outside, and the movable end (11) of the knife gate drives the transmission assembly (3) to move by driving the side of the U-shaped structure to move.

5. The load switch based on vacuum arc extinguishing according to claim 4, characterized in that: The U-shaped structure of the rotating member (34) includes a first side (341) and a second side (342), wherein the first side (341) is a conductive side, and the second side (342) is an insulating side. When the switch is open, the movable end (11) of the knife switch contacts the first side (341); when the switch is closed, the movable end (11) of the knife switch contacts the second side (342).

6. The load switch based on vacuum arc extinguishing according to claim 2, characterized in that: The vacuum interrupter (2) further comprises a movable end guide rod (23), wherein the movable end guide rod (23) is arranged between the movable contact (22) and the first connecting rod (31), the movable contact (22) is fixedly connected to the movable end guide rod (23), and the first connecting rod (31) is movably connected to the movable end guide rod (23).

7. The load switch based on vacuum arc extinguishing according to claim 2, characterized in that: Also includes: A compression spring (4) and a guide rod, wherein the two ends of the compression spring (4) are respectively connected to the first connecting rod (31) and the housing (24) of the vacuum interrupter (2), and the compression spring (4) is sleeved on the guide rod, wherein one end of the guide rod is connected to the first connecting rod (31) and the other end is a free end.

8. The load switch based on vacuum arc extinguishing according to claim 2, characterized in that: Also includes: A torsion spring (5), the torsion spring (5) being arranged at the connection between the first connecting rod (31) and the second connecting rod (32), the torsion spring (5) being used to provide a reset force to the second connecting rod (32) after the opening or closing of the switch is completed, so as to drive the second connecting rod (32) to reset relative to the first connecting rod (31).

9. The load switch based on vacuum arc extinguishing according to claim 5, characterized in that: Also includes: A tension spring (6); the two ends of the tension spring (6) are respectively connected to the housing (24) and the second side (342) of the vacuum interrupter (2), and are used to apply a force to the first side (341) and the knife switch movable end (11) to contact in the first state when the switch is opened.

10. The load switch based on vacuum arc extinguishing according to claim 9, characterized in that: Also includes: A limiting member (7) is provided on the housing (24) of the vacuum interrupter (2); the rotating member (34) is subjected to the tension of the tension spring (6) and abuts against the limiting member (7) in the open state.

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