Closing resistor transmission structure, high-voltage alternating current circuit breaker and working method of high-voltage alternating current circuit breaker

Abstract

The invention belongs to the technical field of circuit breakers, and relates to a closing resistor transmission structure, a high-voltage alternating-current circuit breaker and a working method thereof. The transmission structure comprises a guide piece, a connecting plate, a crank arm, a clamping fork, a closing resistor conducting rod, a closing resistor moving contact system and a closing resistor static contact system, an insulating pull rod and a piston rod are arranged in an arc extinguish chamber of the circuit breaker; a support is fixed in a movable side supporting piece of the arc extinguish chamber; the guide piece is connected into the movable side supporting piece, and a sliding groove is prefabricated in the guide piece; one end of the connecting plate is hinged to the piston rod, and the other end of the connecting plate is hinged to one end of the crank arm; a clamping fork is hinged to the crank arm, one end of a closing resistor conducting rod is horizontally connected to one end of the clamping fork, and the other end of the clamping fork is slidably connected into the sliding groove. And the other end of the closing resistor conducting rod is connected with a closing resistor moving contact system. Therefore, the moving and static side contact transmission system of the closing resistor always moves horizontally in the whole opening and closing process, and the whole resistor system is subjected to small lateral impact force.

Description

Technical Field

[0001] This invention belongs to the field of circuit breaker technology, specifically relating to a closing resistor drive structure, a high-voltage AC circuit breaker and its working method. Background Technology

[0002] Circuit breakers with voltage levels of 363kV and above generally need to be equipped with closing resistors. Circuit breakers with voltage levels of 363kV and above have high opening and closing speeds, with some circuit breakers having closing speeds of up to 5m / s and opening speeds of up to 14m / s. Therefore, a reasonable circuit breaker drive structure is particularly important. This places very high demands on the internal drive components and their connecting parts. Some traditional drive structures may not be able to meet such high requirements, and an unreasonable drive structure can bring risks to the operation of the circuit breaker.

[0003] The transmission system of existing closing resistor devices is generally arranged in parallel with the arc-extinguishing chamber. Most existing transmission systems are based on a four-bar linkage structure. If the transmission linkage system is not designed properly, it will bring a large lateral force to the arc-extinguishing chamber, causing the entire circuit breaker system to be subjected to a large impact force.

[0004] A search revealed a patent document with application number 202411430779.0 disclosing a closing resistor structure for an 800kV fast circuit breaker. Its transmission mechanism involves a crank arm driving the main contact transmission and a resistor contact transmission. The main crank arm rotates to drive a resistor-driven connecting rod, which in turn drives the resistor-driven crank arm, which in turn drives the moving contact connecting rod, ultimately moving the moving contact. This transmission method results in a non-horizontal motion of the moving contact, with an angle relative to the horizontal axis during movement. If the angle between the moving contact connecting rod and the horizontal axis is too large, it will exert a significant lateral force on the moving contact. This large lateral force can cause bending and deformation of components, as well as generate significant friction, leading to substantial wear. Therefore, this poses a significant risk to the strength and reliability of the closing resistor transmission system. Thus, the design of the transmission system needs to consider methods to eliminate lateral forces and improve the stress conditions of the transmission system to enhance the reliability of the circuit breaker. Summary of the Invention

[0005] The purpose of this invention is to provide a closing resistor drive structure, a high-voltage AC circuit breaker and its working method, which solves the problem of lateral force in the existing closing resistor drive system.

[0006] This invention is achieved through the following technical solution: This invention discloses a closing resistor transmission structure, including a guide, a connecting plate, a crank arm, a clamping fork, a closing resistor conductive rod, a closing resistor moving contact system, and a closing resistor stationary contact system. An insulating pull rod and a piston rod are provided in the arc extinguishing chamber of the circuit breaker; a support is fixed in the moving side support of the arc extinguishing chamber; The guide is connected in the moving side support of the arc extinguishing chamber, and a chute is prefabricated on the guide; One end of the connecting plate is hinged to the piston rod, the other end is hinged to one end of the toggle arm, and the other end of the toggle arm is hinged to the support; A clamp fork is hinged on the toggle arm. One end of the closing resistor conducting rod is horizontally connected to one end of the clamp fork, and the other end of the clamp fork is slidably connected to the chute of the guide; The other end of the closing resistor conducting rod is connected to the closing resistor moving contact system. The closing resistor static contact system is arranged on the static side, and the closing resistor static contact system is connected with a closing resistor.

[0007] Furthermore, the guide and the support fixed on the moving side support are on the same center.

[0008] Furthermore, the center point of the clamp fork is named point O, the upper hinge point of the clamp fork is named point A, the lower hinge point of the clamp fork is named point B, the upper hinge point of the connecting plate is named point C, the hinge point of the connecting plate and the toggle arm is named point D, and the hinge point of the toggle arm and the support is named point E; The distance between OA and OB is X1, the distance of OE is X1, and the distance of OD is X2; The opening distance of the main breaking port of the arc extinguishing chamber is X3, and the opening distance of the closing resistor is X4.

[0009] Furthermore, when the speed of the main breaking port of the arc extinguishing chamber is lower than the asynchronous movement of the closing resistor breaking port at different speeds, it should satisfy X3>X4+t*V, where t represents the resistor input time and V represents the closing speed; it is required to satisfy X1>X2.

[0010] Furthermore, when the speed of the main breaking port of the arc extinguishing chamber is higher than the asynchronous movement of the closing resistor breaking port at different speeds, it should satisfy X3<X4+t*V, where t represents the resistor input time and V represents the closing speed; it is required to satisfy X1<X2.

[0011] Furthermore, when the main breaking port and the closing resistor move synchronously at the same speed, it should satisfy X3=X4+t*V, where t represents the resistor input time and V represents the closing speed; it is required to satisfy X1=X2.

[0012] Furthermore, the clamp fork is in sliding contact with the chute through double sliders.

[0013] Furthermore, the clamp fork and the slider are connected by a cylindrical pin.

[0014] The present invention also discloses a high-voltage AC circuit breaker, including the closing resistor transmission structure described above; The high-voltage AC circuit breaker includes an operating mechanism, an arc-extinguishing chamber, and a main contact system; the operating mechanism is connected to an insulating pull rod, and the insulating pull rod is connected to a piston rod; the main contact system includes a moving contact system and a stationary contact system, a moving side support is connected to the connecting housing, the end of the moving side support is connected to a moving side shield, and the moving contact system is connected to the end of the piston rod; The moving contact system of the closing resistor is connected to the conductive rod of the closing resistor and is parallel to the moving contact system.

[0015] Furthermore, when the operating mechanism drives the insulating pull rod to perform the opening movement, it drives the piston rod to move away from the stationary side. The piston rod drives the moving contact system to move away from the stationary side, and the moving contact system separates from the stationary contact system. At the same time, the connecting plate drives the crank arm to rotate clockwise, which drives the upper end of the clamping fork to move up and down in the guide. The lower end of the clamping fork rotates horizontally away from the stationary side, which in turn drives the moving conductive rod of the closing resistor to move horizontally away from the stationary side, and finally drives the moving contact system of the closing resistor to move horizontally. When the operating mechanism drives the insulating pull rod to perform the closing movement, it causes the piston rod to move towards the stationary side. The piston rod then causes the moving contact system to move towards the stationary side, and the moving contact system closes with the stationary contact system. At the same time, the tendency of the connecting plate to move towards the stationary side causes the crank arm to rotate counterclockwise. The upper end of the clamping fork moves up and down in the guide, and the lower end of the clamping fork rotates horizontally towards the stationary side. This, in turn, causes the moving conductive rod of the closing resistor to move horizontally towards the stationary side, and finally causes the moving contact system of the closing resistor to move horizontally towards the stationary side.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects: This invention discloses a closing resistor transmission structure, including a connecting plate, a crank arm, a clamping fork, a guide member, a moving conductive rod of the resistor, and a closing resistor contact system. During the opening and closing process, the connecting plate drives the crank arm to rotate, causing the upper end of the clamping fork to move up and down within the guide member, while the lower end of the clamping fork moves horizontally. This, in turn, drives the moving conductive rod of the closing resistor to move linearly, ultimately causing the moving contact system of the closing resistor to move horizontally. This ensures that the moving and stationary contact transmission system of the closing resistor remains horizontal throughout the entire opening and closing process, minimizing lateral impact forces on the entire resistor system and improving mechanical reliability. In this structure, both the main break transmission and the resistor break movement linkage system move horizontally, reducing lateral impact forces on the entire circuit breaker transmission and improving the mechanical reliability of the circuit breaker.

[0017] This invention, based on the main break transmission structure of the arc-extinguishing chamber, designs an auxiliary closing resistor transmission system. This system, through relevant transmission design, ensures that the closing resistor conductive rod always moves horizontally during the circuit breaker's opening and closing movements, eliminating vertical lateral forces and improving the system's reliability. The arc-extinguishing chamber main break transmission is horizontally and directly connected to the operating mechanism, resulting in a horizontal movement for the entire main break transmission. Compared to existing technologies that use a crank arm connection between the arc-extinguishing chamber main break transmission and the operating mechanism, this significantly reduces vertical lateral forces on the main break transmission, improves the stress state of the entire main break transmission components, and enhances the system's reliability.

[0018] Furthermore, to reduce lateral forces in the transmission system, the guide components and the crank arm are arranged concentrically on the fixed rotation axis, and the distance between the upper holes of the clamping fork and the lower holes of the crank arm is equidistant to reduce horizontal lateral impact forces. Similarly, the distance between the lower holes of the crank arm and the lower holes of the clamping fork is equidistant to reduce vertical lateral impact forces, ensuring that the conductive rod of the resistance transmission system always moves horizontally. Ultimately, this improves the stress state of the entire resistance transmission system, significantly reducing the impact of lateral forces on moving parts and resulting in high mechanical reliability. Furthermore, the upper and lower hole spacing of the clamping fork and the lower hole spacing of the crank arm in the resistance drive system are designed to be equidistant. Based on the motion relationship between the main break and the resistor break, the upper hole spacing of the crank arm is designed with corresponding length matching. Considering the motion relationship between the main break of the arc-extinguishing chamber and the closing resistor break, the closing resistor drive system is designed with three structures: main break movement speed > closing resistor break movement speed, main break movement speed = closing resistor break movement speed, and main break movement speed < closing resistor break movement speed.

[0019] Furthermore, in order to improve the stress state of the clamping fork in contact with the guide, the sliding structure is designed as a double slider sliding contact, which increases the contact area, reduces the stress generated on the contact surface, improves the stress on the guide, and improves the reliability of the circuit breaker. Attached Figure Description Figure 1 This is a schematic diagram of the high-voltage AC circuit breaker structure of the present invention; Figure 2 This is a schematic diagram of the main drive system of the high-voltage AC circuit breaker of the present invention; Figure 3 This is a schematic diagram of the closing resistor break-through transmission system. Figure 4 This is a schematic diagram of the closing resistor drive structure of a high-voltage AC circuit breaker disclosed in this invention; Figure 5 A schematic diagram showing the opening distance between the main break and the closing resistor break of the circuit breaker. Figure 6 This is a schematic diagram of the structure of the first type of closing resistor drive system; Figure 7This is a schematic diagram of the second type of closing resistor drive system; Figure 8 This is a schematic diagram of the third type of closing resistor drive system; Figure 9 A schematic diagram illustrating the angle principle of the circuit breaker closing resistor drive system.

[0020] 1. Operating mechanism; 2. Mechanism connecting rod; 3. Insulating pull rod; 4. Connecting housing; 5. Support cylinder; 6. Piston rod; 7. Guide component; 8. Connecting plate; 9. Crank arm; 10. Clamping fork; 11. Closing resistor conductive rod; 12. Moving side support component; 13. Moving side shield; 14. Moving contact system; 15. Stationary contact system; 16. Stationary side outgoing conductor; 18. Closing resistor moving contact system; 19. Closing resistor stationary contact system; 20. Closing resistor. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the present invention clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention; that is, the described embodiments are only a part of the embodiments of the present invention, and not all of them.

[0022] The components described and illustrated in the accompanying drawings and embodiments of this invention can be arranged and designed in various different configurations. Therefore, the detailed description of the embodiments of the invention provided in the following drawings is not intended to limit the scope of the claimed invention, but merely to illustrate one selected embodiment of the invention. All other embodiments obtained by those skilled in the art based on the accompanying drawings and embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0023] It should be noted that the terms "comprising," "including," or any other variations are intended to cover non-exclusive inclusion, such that a process, element, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to the process, element, method, article, or apparatus. Furthermore, the terms "horizontal" and "vertical" are based on the orientation and positional relationship of the devices or components shown in the accompanying drawings and are used only for better description of the invention, not to require that the shown devices, components, or apparatus must have that specific orientation, and therefore should not be construed as limiting the invention.

[0024] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0025] like Figure 1The circuit breaker structure shown includes an operating mechanism 1, a horizontally arranged arc-extinguishing chamber, and a main contact system. The connecting housing 4 of the arc-extinguishing chamber contains a mechanism connecting rod 2, an insulating pull rod 3, and a piston rod 6. The operating mechanism 1 is connected to the insulating pull rod 3 via the mechanism connecting rod 2, and the insulating pull rod 3 is connected to the piston rod 6. The main contact system includes a moving contact system 14 and a stationary contact system 15. The connecting housing 4 is connected to a moving-side support member 12 via a support cylinder 5. The end of the moving-side support member 12 is connected to a moving-side shield 13. The moving contact system 14 is connected to the piston rod 6. A stationary-side outgoing conductor 16 is also provided on the stationary side.

[0026] The insulating rod 3 of the arc-extinguishing chamber is driven horizontally by the operating mechanism 1. The insulating rod 3 pulls the piston rod 6 of the main contact horizontally, and the piston rod 6 drives the entire contact system to open and close. In this way, the main drive system with direct connection design is not subject to lateral force, which not only improves the strength of the circuit breaker's drive components, but also reduces the risk of foreign objects after the circuit breaker's opening and closing operation. like Figure 4 As shown, the present invention discloses a high-voltage AC circuit breaker closing resistor transmission structure, including a guide 7, a connecting plate 8, a crank arm 9, a clamping fork 10, a closing resistor conductive rod 11, a closing resistor moving contact system 18, and a closing resistor stationary contact system 19. The guide 7 is connected to the moving side support 12 of the arc-extinguishing chamber. One end of the connecting plate 8 is hinged to the piston rod 6, and the other end is hinged to one end of the crank arm 9. The other end of the crank arm 9 is hinged to a support, which is fixed to the moving side support 12. The closing resistor conductive rod 11 is horizontally connected to one end of the clamping fork 10. The closing resistor moving contact system 18 is connected to the closing resistor conductive rod 11 and is parallel to the moving contact system 14. The closing resistor stationary contact system 19 is located on the stationary side and is connected to a closing resistor 20. A clamping fork 10 is hinged to the crank arm 9. One end of the clamping fork 10 is hinged to the closing resistor conductive rod 11, and the other end is slidably connected to the slide groove of the guide member 7.

[0027] The closing resistor drive is also driven by the insulating pull rod 3, which moves horizontally on the main break. When the insulating pull rod 3 moves to the right, i.e., when the circuit is open, it drives the piston rod 6 to move to the right. The piston rod 6 drives the moving contact system 14 to move to the right, and then the moving contact system 14 moves away from the stationary side together, and the moving contact system 14 and the stationary contact system 15 are opened. At the same time, since one end of the crank arm 9 is fixed, the tendency of the connecting plate 8 to the right drives the crank arm 9 to rotate clockwise, so that the upper end of the clamp fork 10 moves up and down in the guide 7, and the lower end of the clamp fork 10 moves horizontally to the right, which in turn drives the moving conductive rod 11 of the closing resistor to move horizontally to the right, and finally drives the moving contact system 18 of the closing resistor to move horizontally. Under the drive of the motion system, the moving contact system 18 and the stationary contact system 19 of the closing resistor always move horizontally and are open. The entire closing resistor drive system has no vertical lateral impact force.

[0028] When the insulating pull rod 3 moves leftward for closing, it drives the piston rod 6 to move leftward. The piston rod 6 drives the moving contact system 14 to move leftward, and further drives the moving contact system 14 to move towards the static side, and the moving contact system 14 closes with the static contact system 15. At the same time, since one end of the toggle arm 9 is fixed, the leftward trend of the connecting plate 8 drives the toggle arm 9 to rotate counterclockwise, causing the upper end of the fork 10 to move up and down in the guide member 7, and the lower end of the fork 10 to move horizontally leftward, thereby driving the moving conducting rod 11 of the closing resistor to move horizontally leftward, and finally driving the moving contact system 18 of the closing resistor to move horizontally leftward. Under the drive of the moving system, the moving contact system 18 of the closing resistor and the static contact system 19 of the closing resistor always perform horizontal closing movement, and there is no vertical lateral impact force on the entire closing resistor transmission system.

[0029] During the specific design, as Figure 5 shown, considering the different opening distances of the main break and the closing resistor break, the closing resistor transmission system has different structural designs, where the opening distance of the main break of the arc extinguishing chamber is X3, and the opening distance of the closing resistor is X4.

[0030] As Figure 6 shown, the center point of the fork 10 is named point O, the upper hinge point of the fork 10 is named point A, the lower hinge point is named point B, the upper hinge point of the connecting plate 8 is named point C, the hinge point of the connecting plate 8 and the toggle arm 9 is named point D, and the hinge point of the toggle arm 9 and the support is named point E. The distance between OA and OB is X1, the distance of OE is X1, and the distance of OD is X2.

[0031] When X3 > X4 + t*V, where t represents the resistor input time and V represents the closing speed, it is necessary for the speed of the main break of the arc extinguishing chamber to be lower than the asynchronous movement speed of the closing resistor break. Therefore, the hole distance on the toggle arm ⑨ is X1 > X2.

[0032] As Figure 7 shown, when X3 < X4 + t*V, it is necessary for the speed of the main break of the arc extinguishing chamber to be higher than the asynchronous movement speed of the closing resistor break. Therefore, the hole distance on the toggle arm 9 is X1 < X2. The structure of the closing resistor transmission system changes. As Figure 7 shown, the fork 10 will be relatively small. As Figure 8 shown, when X3 = X4 + t*V, it is necessary for the main break and the closing resistor to move synchronously and at the same speed. Therefore, the upper and lower hole distances of the toggle arm are designed to be equal, that is, X1 = X2. As Figure 9As shown, in all three cases, the guide 7 and the support fixed on the moving side support 12 must be on the same center. The hole spacing on the upper part of the clamping fork 10 and the hole spacing on the lower part of the crank arm 9 are equal in length X1. This results in a vertical angle α between the crank arm 9 and the guide 7, ensuring that the upper shaft of the clamping fork 10 always moves up and down along the axis of the guide 7 without any horizontal lateral force. This reduces the wear of the guide 7 and also reduces the horizontal impact force on the entire resistor system. The hole spacing on the lower part of the crank arm 9 and the hole spacing on the lower part of the clamping fork 10 are equal in length X1. This results in a horizontal angle β between the crank arm 9 and the clamping fork 10. Therefore, the closing resistor conductive rod 11, the closing resistor moving contact system 18, and the closing resistor stationary contact system 19 always move horizontally without any vertical lateral force.

[0033] Since the clamping fork 10 needs to slide up and down within the guide member 7, unlike the existing pin transmission method, the pin sliding contact is changed to double slider sliding contact, which increases the contact area, reduces the contact stress on the contact surface, improves the force on the guide member 7, and improves the reliability of the transmission.

[0034] Specifically, the clamp fork 10 and the slider are connected by a cylindrical pin.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A closing resistor transmission structure, characterized in that, It includes a guide member (7), a connecting plate (8), a toggle arm (9), a clamp fork (10), a closing resistor conducting rod (11), a closing resistor moving contact system (18), and a closing resistor static contact system (19); An insulating pull rod (3) and a piston rod (6) are provided in the arc extinguishing chamber of the circuit breaker; a support is fixed in the moving side support member (12) of the arc extinguishing chamber; The guide member (7) is connected in the moving side support member (12) of the arc extinguishing chamber, and a chute is prefabricated on the guide member (7); One end of the connecting plate (8) is hinged to the piston rod (6), and the other end is hinged to one end of the toggle arm (9), and the other end of the toggle arm (9) is hinged to the support; A clamp fork (10) is hinged on the toggle arm (9), one end of the closing resistor conducting rod (11) is horizontally connected to one end of the clamp fork (10), and the other end of the clamp fork (10) is slidably connected in the chute of the guide member (7); The other end of the closing resistor conducting rod (11) is connected to the closing resistor moving contact system (18), the closing resistor static contact system (19) is arranged on the static side, and the closing resistor static contact system (19) is connected to a closing resistor (20).

2. The closing resistor transmission structure according to claim 1, characterized in that, The guide member (7) and the support fixed on the moving side support member (12) are on the same center.

3. The closing resistor transmission structure according to claim 1, characterized in that, The center point of the clamp fork (10) is named point O, the upper hinge point of the clamp fork (10) is named point A, the lower hinge point is named point B, the upper hinge point of the connecting plate (8) is named point C, the hinge point of the connecting plate (8) and the toggle arm (9) is named point D, and the hinge point of the toggle arm (9) and the support is named point E; The distance between OA and OB is X1, the distance of OE is X1, and the distance of OD is X2; The opening distance of the main break of the arc extinguishing chamber is X3, and the opening distance of the closing resistor is X4.

4. The closing resistor transmission structure according to claim 3, characterized in that, When the speed of the main break of the arc extinguishing chamber is lower than the asynchronous movement of the closing resistor break, it should satisfy X3>X4+t*V, where t represents the resistor input time and V represents the closing speed; it is required to satisfy X1>X2.

5. The closing resistor transmission structure according to claim 3, characterized in that, When the speed of the main break of the arc extinguishing chamber is higher than the asynchronous movement of the closing resistor break, it should satisfy X3<X4+t*V, where t represents the resistor input time and V represents the closing speed; it is required to satisfy X1<X2.

6. The closing resistor transmission structure according to claim 3, characterized in that, When the main break and the closing resistor move synchronously and at the same speed, it should satisfy X3=X4+t*V, where t represents the resistor input time and V represents the closing speed; it is required to satisfy X1=X2.

7. The closing resistor transmission structure according to claim 1, characterized in that, The clamp fork (10) is in sliding contact with the chute through double sliders.

8. The closing resistor transmission structure according to claim 7, characterized in that, The clamp fork (10) and the slider are connected by a cylindrical pin.

9. A high-voltage AC circuit breaker, characterized in that, It includes the closing resistor transmission structure according to any one of claims 1-8; The high-voltage AC circuit breaker includes an operating mechanism (1), an arc extinguishing chamber, and a main contact system; the operating mechanism (1) is connected to the insulating pull rod (3), and the insulating pull rod (3) is connected to the piston rod (6); the main contact system includes a moving contact system (14) and a static contact system (15), the connecting housing (4) is connected to the moving side support member (12), the end of the moving side support member (12) is connected to the moving side shield (13), and the moving contact system (14) is connected to the end of the piston rod (6); The closing resistor moving contact system (18) is connected to the closing resistor conducting rod (11) and is parallel to the moving contact system (14).

10. The operating method of the high-voltage AC circuit breaker according to claim 9, characterized in that, When the operating mechanism (1) drives the insulating pull rod (3) to perform the opening movement, it drives the piston rod (6) to move away from the stationary side. The piston rod (6) drives the moving contact system (14) to move away from the stationary side, and the moving contact system (14) and the stationary contact system (15) are opened. At the same time, the connecting plate (8) drives the crank arm (9) to rotate clockwise, which drives the upper end of the clamp fork (10) to move up and down in the guide (7). The lower end of the clamp fork (10) rotates horizontally away from the stationary side, which in turn drives the closing resistor moving conductive rod (11) to move horizontally away from the stationary side, and finally drives the closing resistor moving contact system (18) to move horizontally. When the operating mechanism (1) drives the insulating pull rod (3) to perform the closing movement, it drives the piston rod (6) to move towards the stationary side. The piston rod (6) drives the moving contact system (14) to move towards the stationary side, and the moving contact system (14) and the stationary contact system (15) close. At the same time, the trend of the connecting plate (8) towards the stationary side drives the crank arm (9) to rotate counterclockwise. The upper end of the clamp fork (10) moves up and down in the guide (7), and the lower end of the clamp fork (10) rotates horizontally towards the stationary side, thereby driving the closing resistor moving conductive rod (11) to move horizontally towards the stationary side, and finally driving the closing resistor moving contact system (18) to move horizontally towards the stationary side.

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