A dual-control system for the hydraulic operating mechanism of a fast circuit breaker

Abstract

This utility model relates to a dual-control system for a hydraulic operating mechanism of a fast circuit breaker, including a control valve assembly and an electromagnetic repulsion tripping assembly. The control valve assembly includes a control valve seat and a control valve core. The electromagnetic repulsion tripping assembly includes a tripping assembly frame and a central connecting rod that slides along the movement direction of the control valve core within the frame. The central connecting rod pulls the control valve core to the right to achieve rapid tripping. The control valve seat has a low-pressure oil port, a variable oil port, and a high-pressure oil port arranged from left to right. When the central connecting rod pulls the control valve core to the right to achieve rapid tripping, the oil circuit switching valve is opened through the connecting rod assembly. This utility model adopts a repulsion mechanism and a high-flow hydraulic valve fusion triggering technology to replace the traditional electromagnetic coil, shortening the mechanism start-up time, increasing the tripping speed, and shortening the contact mechanical separation time. Based on this, a traditional electromagnetic valve is provided, and a dual-redundancy design is adopted, so that the failure of one tripping device does not affect the reliable operation of the other.

Description

Technical Field

[0001] This utility model relates to the field of circuit breaker technology, specifically to a dual-control system for the hydraulic operating mechanism of a fast circuit breaker. Background Technology

[0002] With the rapid growth of the national economy, my country's power grid has been continuously expanding, and the level of short-circuit current in the system has been increasing year by year. Excessive short-circuit current can harm the safe and stable operation of the power system and electrical equipment, becoming a bottleneck for the safe operation of the power system. To avoid the series of hazards caused by large short-circuit currents, the level of short-circuit current must be limited within a safe margin. Fast circuit breakers are the core equipment for achieving flexible suppression of short-circuit current, enabling rapid clearing of short-circuit faults, and are of great significance for ensuring the safe and stable operation of the power system.

[0003] The 550 kV fast circuit breaker requires a tripping time of less than 8 ms and a short-circuit current breaking time of less than 25 ms. To meet these requirements, key technological bottlenecks in fast-breaking mechanisms and arc-extinguishing chambers need to be overcome to shorten tripping time and improve short-circuit current breaking capacity. Conventional 550 kV SF6 circuit breakers use a hydraulic disc spring operating mechanism, which is triggered by a solenoid valve. This mechanism has a long start-up time of 11-14 ms and insufficient operating power, resulting in a slow tripping speed and a contact mechanical separation time of 11-15 ms. Clearly, the existing hydraulic disc spring operating mechanism cannot meet the fast-breaking requirements. Therefore, a new fast hydraulic operating mechanism is needed to meet these requirements, and the development of a fast tripping device is crucial to achieving the fast-action function of the operating mechanism.

[0004] The applicant's patent CN119725011A is a fast tripping control system for a hydraulic operating mechanism, which can realize the fast tripping of the circuit breaker and also provides a dual redundancy design. However, the structure of this application is relatively complex and the working stability is low. Utility Model Content

[0005] This utility model addresses the shortcomings of existing technologies by providing a dual-control system for the hydraulic operating mechanism of a fast circuit breaker.

[0006] This utility model is achieved through the following technical solution: a dual-control system for a hydraulic operating mechanism of a fast circuit breaker, including a control valve assembly and an electromagnetic repulsion trip assembly. The control valve assembly includes a control valve seat and a control valve core. The electromagnetic repulsion trip assembly includes a trip assembly frame and a central connecting rod slidably connected within the trip assembly frame along the movement direction of the control valve core. The central connecting rod pulls the control valve core to the right to achieve fast tripping. The control valve seat has a low-pressure oil port, a variable oil port, and a high-pressure oil port arranged from left to right. A left valve core seat and a right valve core seat are fixedly connected inside the control valve seat, wrapping around the left and right ends of the control valve core. Pistons A3, A2, and A1 are sequentially fixed to the control valve core. The left side of piston A3 and the left valve core seat form cavity A3. The right side of piston A1 and the right valve core seat form chamber A1. The right side of piston A2 and the left side of piston A3 are connected through a connecting hole. In the open state, the right side of piston A2 and the right valve core seat form chamber A2, and chamber A2 is connected to the high-pressure oil port. The control valve seat is equipped with an oil circuit switching valve. The two ends of the oil circuit switching valve are connected to chamber A1 and the variable oil port, respectively. When the central connecting rod pulls the control valve core to the right to achieve rapid opening, the oil circuit switching valve is opened through the connecting rod assembly, allowing the oil in chamber A1 to enter the variable oil port.

[0007] In this scheme, the central connecting rod pulls the control valve core to move to the right to achieve rapid opening. During rapid opening, the oil circuit switching valve is opened through the connecting rod assembly, allowing the oil in chamber A1 to enter the variable oil port Z, thereby increasing the moving speed of the control valve core and thus increasing the opening speed.

[0008] As an optimization, a connector is fixed to the left end of the central connecting rod, and the connector has a cavity inside. A boss located in the cavity is fixed to the right end of the control valve core. In this design, the control valve core is pulled to the right by moving the connector to the right, thereby pulling the boss. After the control valve core is opened to the right, the connector can be separated from the control valve core by moving to the left, thus facilitating the leftward movement of the control valve core to achieve the closing operation.

[0009] As an optimization, an oil buffer located on the right side of the central connecting rod is fixed to the tripping assembly frame. The oil buffer contains a return spring. This buffers the central connecting rod during tripping. After the central connecting rod trips to the right to complete the tripping operation, the return spring pushes the central connecting rod to the left to reset it, separating the central connecting rod from the control valve core. This facilitates the control valve core to move to the left to complete the closing operation.

[0010] As an optimization, the linkage assembly includes a fixed mounting block and a crank arm hinged to the mounting block. A push rod is provided between the crank arm and the oil circuit switching valve. One end of the push rod is hinged to the mounting block, and one end of the crank arm is connected to the connector via a pull rod. When the central linkage quickly opens to the right, the pull rod drives the upper end of the crank arm to swing to the right, and the lower end of the crank arm swings to the left, pushing the push rod to swing to the left to open the oil circuit switching valve.

[0011] As an optimization, one end of the pull rod is hinged to the crank arm, and the other end is hinged to the connecting member. This facilitates the swinging of the crank arm by moving the connecting member left and right.

[0012] As an optimization, the oil circuit switching valve includes a switching valve seat and a switching valve core. The switching valve seat has an inlet, an outlet, and an oil passage connecting the inlet and outlet. The switching valve seat contains a steel ball and a clamping spring that drives the steel ball to block the oil passage. When the push rod swings to the left, it clamps the switching valve core, and the switching valve core pushes open the steel ball, thus connecting the inlet and outlet. In this solution, pressing down the switching valve core opens the oil circuit switching valve by pushing open the steel ball. After the pressure on the switching valve core is released, the clamping spring's force seals the steel ball in the oil passage, closing the oil circuit switching valve.

[0013] As an optimization, the control valve assembly further includes a tripping solenoid valve that controls the control valve core to move to the right to achieve tripping, and a closing solenoid valve that controls the control valve core to move to the left to achieve closing. The closing solenoid valve is connected to the high-pressure oil port and chamber A1, and the tripping solenoid valve is connected to the low-pressure oil port and chamber A1. The pressure-bearing cross-sectional areas of pistons A3, A2, and A1 are S3, S2, and S1, respectively, and S1 < S2 < S3, S1 + S2 > S3. Thus, tripping and closing operations can be achieved through the closing solenoid valve and the tripping solenoid valve, realizing dual control of tripping.

[0014] As an optimization, during rapid tripping, after the central connecting rod pulls the control valve core a certain distance, the oil pressure difference between the pressure-bearing cross-sectional areas S3 and S2 drives the control valve core to continue moving to the right, achieving rapid tripping. This allows for rapid tripping when the repulsive force of the repulsive plate is at its maximum, and subsequent rapid tripping is achieved through the oil pressure difference after the repulsive plate thrust decreases, thereby improving the overall tripping speed.

[0015] As an optimization, two trip solenoid valves are provided, each connected to the low-pressure oil port and the A1 chamber respectively. This design incorporates two trip solenoid valves, thereby improving system stability and preventing system failure due to a single trip solenoid valve malfunction.

[0016] As an optimization, two repulsion discs are fixedly connected to the central connecting rod, and two trip coils located to the left of the two repulsion discs are fixedly connected to the trip assembly frame. In this solution, by setting two repulsion discs and two trip coils, the electromagnetic forces generated by either the main or auxiliary trip coils being energized simultaneously do not affect each other. That is, when the main trip coil is energized, it only drives the main repulsion disc to move and will not affect the auxiliary repulsion disc, and vice versa. Moreover, when any set of trip coils and repulsion discs are working normally, the electromagnetic repulsion trip assembly can drive the control valve to complete the oil circuit switching and realize the rapid tripping of the switch.

[0017] The beneficial effects of this utility model are as follows: This utility model provides a dual-control system for the hydraulic operating mechanism of a fast circuit breaker. It employs a repulsion mechanism and a high-flow hydraulic valve fusion triggering technology to replace the traditional electromagnetic coil, shortening the mechanism start-up time, increasing the opening speed, and reducing the contact mechanical separation time. This solves the problems of slow electromagnetic valve response, long operating time, and limited opening speed in existing conventional SF6 circuit breakers. Furthermore, it incorporates a traditional electromagnetic valve with a dual-redundancy design, ensuring that a failure in one tripping device does not affect the reliable operation of the other. Attached Figure Description

[0018] Figure 1 This is an internal sectional view of the present invention in the closed state;

[0019] Figure 2 This is an internal sectional view of the control valve assembly in the closed state of this utility model;

[0020] Figure 3 This is an internal sectional view of the circuit breaker opening process of this utility model;

[0021] Figure 4 This is an internal sectional view of the control valve assembly during the tripping process of this utility model;

[0022] Figure 5 This is an internal sectional view of the present invention in the open state;

[0023] Figure 6 This is an internal sectional view of the control valve assembly in the open state of this utility model;

[0024] Figure 7 This is a cross-sectional view of the control valve core of this utility model;

[0025] Figure 8 This is a cross-sectional view of the right valve core seat of this utility model;

[0026] Figure 9 This is a cross-sectional view of the oil circuit switching valve of this utility model;

[0027] Figure 10 This is a cross-sectional view of the linkage assembly of this utility model;

[0028] As shown in the figure:

[0029] 1. Control valve seat; 2. Left valve core seat; 3. Right valve core seat; 4. Control valve core; 41. A1 piston; 42. A2 piston; 43. A3 piston; 44. Connecting hole; 5. Closing solenoid valve; 6. Opening solenoid valve; 7. Right pressure plate; 8. Oil circuit switching valve; 81. Switching valve seat; 82. Inlet; 83. Outlet; 84. Switching valve core; 85. Steel ball; 86. Slider; 87. Compression spring; 9. Linkage assembly; 91. Pull rod; 92. Crank arm; 93. Push rod; 94. Mounting block; 10. Trip assembly. Components: 11. Frame, 12. Central connecting rod, 13. Connecting piece, 14. Boss, 15. Repulsion plate, 16. Tripping coil, 17. Oil buffer, 18. Repulsion plate, 19. Spacer, 20. Guide sleeve, 21. Buffer cap, 22. Adjusting screw, 23. Buffer plate, 24. Crank arm, 25. Crank arm mounting seat, 26. Adjusting bolt, 27. Slide valve push rod, 28. Crank arm return spring, 29. Slide valve seat, 30. Slide valve core, 31. Slide valve return spring, T. Low-pressure oil port, P. High-pressure oil port, Z. Variable oil port. Detailed Implementation

[0030] To clearly illustrate the technical features of this solution, the following detailed implementation method will be used to explain the solution.

[0031] like Figures 1-10 As shown, the present invention discloses a dual-control system for a hydraulic operating mechanism of a fast circuit breaker, comprising a control valve assembly and an electromagnetic repulsion tripping assembly.

[0032] The electromagnetic repulsion tripping assembly includes a tripping assembly frame 10 and a central connecting rod 11 slidably connected to the tripping assembly frame. Two repulsion disks 14 are fixedly connected to the central connecting rod 11. Two tripping coils 15 are fixedly connected to the left side of the two repulsion disks 14 respectively in the tripping assembly frame. The two tripping coils 15 respectively drive the two repulsion disks 14 to work. The two tripping coils 15 are the main tripping coil and the auxiliary tripping coil.

[0033] When either the main or auxiliary trip coil is energized, or simultaneously, the electromagnetic forces generated do not affect each other. That is, when the main trip coil is energized, it only drives the main repulsion plate to move and will not affect the auxiliary repulsion plate. The reverse is also true. Furthermore, when either the trip coil and the repulsion plate are working normally, the electromagnetic repulsion tripping assembly can drive the control valve assembly to complete the oil circuit switching and achieve rapid tripping of the switch.

[0034] An oil buffer 16 is fixed to the right end of the release assembly frame 10, located to the right of the central connecting rod 11. The oil buffer 16 is installed at the center of the tail pressure plate. The oil buffer 16 is equipped with a return spring, so after buffering is completed, the central connecting rod 11 can be pushed to the left to achieve reset.

[0035] At least one repulsion plate 14 is provided on the side away from the trip coil 15 to buffer the movement of the repulsion plate 14 to the right. The trip assembly frame 10 is connected in series with the trip coil 15, buffer pad, tail pressure plate, etc. by multiple support rods and fixed on the right pressure plate 7 at the right end of the control valve seat 1. Spacers are provided between the components to achieve separation.

[0036] The control valve assembly includes a control valve seat 1 and a control valve core 4. The control valve core 4 moves axially within the control valve seat 1. In this embodiment, the control valve core 4 moves to the right to open the circuit breaker and moves to the left to close the circuit breaker. The right end of the control valve core 4 extends out of the control valve seat 1 and is coaxial with the central connecting rod 11. The central connecting rod 11 slides along the moving direction of the control valve core 4. The central connecting rod 11 can pull the control valve core 4 to the right to achieve rapid opening.

[0037] The connection between the central connecting rod 11 and the control valve core 4 is as follows: a connecting piece 12 is fixedly connected to the left end of the central connecting rod 11, and a cavity is provided inside the connecting piece 12. A boss 13 located in the cavity is fixedly connected to the right end of the control valve core 4. Therefore, when the central connecting rod 11 moves to the right, it pulls the control valve core 3 to the right by pulling the boss 13. When the central connecting rod 11 returns to its original position to the left, the space in the cavity is left to facilitate the control valve core 3 to return to its original position to the left. In this structure, the connection between the central connecting rod 11 and the control valve core 4 is changed from a threaded connection structure to a hollow sleeve structure, which can effectively solve the problem of large coaxiality caused by the connection between the moving components of the electromagnetic repulsion trip assembly and the moving components of the control valve, that is, the large inclination between the moving components of the two along the axis center, which leads to the breakage of the middle connecting rod of the electromagnetic repulsion trip assembly due to uneven force and the jamming of the control valve core.

[0038] The control valve seat 1 has a low-pressure oil port T, a variable oil port Z, and a high-pressure oil port P arranged from left to right. The control valve seat 1 has a left valve core seat 2 and a right valve core seat 3 fixedly connected to the left and right ends of the control valve core 4. The control valve core 4 has an A3 piston 43, an A2 piston 42, and an A1 piston 41 fixedly connected in sequence. The left side of the A3 piston 43 and the left valve core seat 2 form the A3 cavity. The right side of the A1 piston 41 and the right valve core seat 3 form the A1 cavity. The right side of the A2 piston 42 and the left side of the A3 piston 43 are connected through a connecting hole 44. In the open state, the right side of the A2 piston 42 and the right valve core seat 3 form the A2 cavity, and the A2 cavity is connected to the high-pressure oil port P. The control valve seat 1 is equipped with an oil circuit switching valve 8, and the two ends of the oil circuit switching valve 8 are connected to the A1 cavity and the variable oil port Z, respectively.

[0039] When the central connecting rod 11 pulls the control valve core 4 to the right to achieve rapid opening, the oil circuit switching valve 8 is opened through the connecting rod assembly 9, allowing the oil in chamber A1 to enter the variable oil port Z. In this application, the central connecting rod 11 pulls the control valve core 4 to the right to achieve rapid opening, and during rapid opening, the oil circuit switching valve 8 is opened through the connecting rod assembly 9, allowing the oil in chamber A1 to enter the variable oil port Z, thereby increasing the movement speed of the control valve core and thus increasing the opening speed.

[0040] Specifically, such as Figure 10 As shown, the linkage assembly 9 includes a fixed mounting block 94 and a crank arm 92 hinged to the mounting block 94. The mounting block 94 is fixed in the cavity of the right pressure plate 7. The middle position of the crank arm 92 is hinged to the mounting block 94, so that the upper and lower ends of the crank arm 92 can swing left and right in opposite directions. The upper end of the crank arm 92 is connected to the connector 12 through a pull rod 91. Specifically, one end of the pull rod 91 is hinged to the crank arm 92, and the other end is hinged to the connector 12. Thus, the left and right swing of the upper end of the crank arm 92 is realized by the left and right movement of the connector 12.

[0041] A push rod 93 is provided between the crank arm 92 and the oil circuit switching valve 8. The upper end of the push rod 93 is hinged to the mounting block 94. When the central connecting rod 11 quickly opens to the right, the upper end of the crank arm 92 swings to the right through the pull rod 91, and the lower end of the crank arm 92 swings to the left, pushing the push rod 93 to swing to the left to open the oil circuit switching valve 8.

[0042] like Figure 9 As shown, the oil circuit switching valve 8 includes a switching valve seat 81 and a switching valve core 84. The switching valve seat 81 has an inlet 82, an outlet 83, and an oil passage connecting the inlet 82 and the outlet 83. The outlet 83 is connected to the variable oil port Z, and the inlet 82 is connected to the A1 cavity. The oil passage is a stepped shaft. The switching valve seat 81 contains a steel ball 85 and a compression spring 87 that drives the steel ball 85 to block the oil passage. The compression spring 87 presses the steel ball 85 against the small-diameter end of the stepped shaft to close the oil circuit switching valve 8.

[0043] The switching valve core 84 slides in the switching valve seat 81, with the right end of the switching valve core 84 protruding outside the switching valve seat 81. When the push rod 93 swings to the left, it presses the switching valve core 84, and the steel ball 85 is pushed open by the switching valve core 84 to achieve the connection between the liquid inlet 82 and the liquid outlet 83.

[0044] The control valve assembly also includes a tripping solenoid valve 6 that controls the control valve core 4 to move to the right to achieve tripping, and a closing solenoid valve 5 that controls the control valve core 4 to move to the left to achieve closing. Both the tripping solenoid valve 6 and the closing solenoid valve 5 are fixed on the outside of the control valve seat 1. In this embodiment, there are two tripping solenoid valves 6, namely a main tripping solenoid valve and a secondary tripping solenoid valve, which are arranged in parallel to ensure the stability of tripping.

[0045] The closing solenoid valve 5 connects the high-pressure oil port P and chamber A1, while the two opening solenoid valves 6 connect the low-pressure oil port T and chamber A1, respectively.

[0046] The compressible cross-sectional areas of pistons A3 (43), A2 (42), and A1 (41) are S3, S2, and S1, respectively. Since piston A3 (43) is fully inserted into the inner hole of the left valve core seat 2, its compressible cross-sectional area is the same as its outer diameter cross-sectional area. Since the right end of piston A2 (42) is inserted into the left opening of the right valve core seat 3, its compressible cross-sectional area is the outer diameter cross-sectional area of ​​the inserted right end of piston A2 (42) minus the cross-sectional area of ​​piston A1 (41). The compressible cross-sectional area of ​​piston A1 (41) is its outer diameter cross-sectional area minus the cross-sectional area of ​​the valve core rod. Furthermore, S1 < S2 < S3, and S1 + S2 > S3.

[0047] How to use this utility model:

[0048] When the closing operation is performed, the closing solenoid valve 5 is energized, introducing the high-pressure oil in the high-pressure oil port P into chamber A1. Chambers A2 and A3 are also connected to the high-pressure oil in the high-pressure oil port P. Since S1+S2>S3, the resultant force on the control valve core 4 is to the left, introducing the high-pressure oil into the hydraulic working cylinder, causing the working cylinder to move rapidly. The working cylinder is connected to the moving end of the arc-extinguishing chamber, driving the arc-extinguishing chamber to move rapidly, thus realizing the closing operation.

[0049] There are two control modes for the tripping operation: one is to perform the tripping operation through the tripping solenoid valve 6, and the other is to achieve rapid tripping of the circuit breaker through the electromagnetic repulsion tripping assembly.

[0050] When the tripping operation is performed by the tripping solenoid valve 6, the tripping solenoid valve 6 is energized, and the low-pressure oil from the low-pressure oil port T is introduced into the A1 chamber, making the A1 chamber contain low-pressure oil. At this time, since S3 > S2, the resultant force on the control valve core 4 is to the right, which introduces the low-pressure oil into the hydraulic working cylinder, causing the working cylinder to move rapidly. The working cylinder is connected to the moving end of the arc-extinguishing chamber, driving the arc-extinguishing chamber to move rapidly, thereby realizing the tripping operation.

[0051] The working process of achieving rapid circuit breaker tripping using the electromagnetic repulsion tripping assembly is as follows: The tripping coil 15 is energized by an external control power supply, generating a pulse current in the coil. The pulse current generates an alternating magnetic field around the coil and induces a reverse eddy current on the repulsion disk 14. The magnetic field generated by the eddy current interacts with the magnetic field generated by the coil current to generate an electromagnetic force. Driven by the electromagnetic force, the electromagnetic repulsion disk moves to the right, thereby driving the central connecting rod 11 to move to the right, pulling the control valve core 4 to move to the right, and the control valve reverses, realizing the rapid tripping action of the mechanism.

[0052] When the central connecting rod 11 moves to the right, the upper end of the crank arm 92 swings to the right through the pull rod 91, and the lower end of the crank arm 92 swings to the left, pushing the push rod 93 to swing to the left, pressing the switching valve core 84. The switching valve core 84 pushes open the steel ball 85 to connect the inlet port 82 and the outlet port 83. At this time, the oil in the A1 chamber enters the variable oil port Z, which increases the oil discharge speed in the A1 chamber. This can meet the requirements of rapid switching of the oil circuit driven by the electromagnetic repulsion trip assembly, effectively shortening the switching time of the control valve and improving the response speed of the control valve.

[0053] In the initial stage of the repulsion disk 14's operation, a large repulsion force acts on the repulsion disk 14. In the final stage of the repulsion disk 14's movement, in order to reduce the impact of the valve core on the valve port, the repulsion disk 14 only drives the control valve core 4 to move a large part of the stroke. At this time, the A2 piston 42 disengages from the left valve core seat 2, the variable oil port Z is low-pressure oil, and the A1 chamber is connected to the variable oil port Z. At this time, since S3 > S2, the resultant force on the control valve core 4 is to the right, thereby pushing the valve core 4 to move the remaining small part of the stroke. This structure can shorten the mechanism start-up time to within 4ms and reduce the mechanical impact between the valve core and the valve core seat sealing part inside the control valve, greatly improving the service life of the control valve.

[0054] After the electromagnetic repulsion trip assembly drives the control valve to open to the desired position, under the action of the rear-mounted oil buffer 16 and the limit plate, as... Figure 6 As shown, the repulsion plate 14 returns to and remains in its original position (left end), the oil circuit switching valve 8 closes under the action of the clamping spring 87, the high and low oil pressure variable oil chambers Z and A1 of the control valve are closed, and the high flow hydraulic valve switches back to the conventional solenoid valve control valve structure.

[0055] The electromagnetic repulsion trip assembly is driven by energizing the repulsion coil, which generates a very large repulsion force on the repulsion disc 14. This allows for rapid pulling of the control valve core 4 to achieve reversal. The repulsion starting force is very large, enabling rapid start-up. However, the repulsion force decays very quickly, eventually reaching zero. Therefore, in order for the control valve to maintain its self-holding and self-sealing capabilities in both open and closed states, it is still necessary to provide the opening and closing holding oil pressure through the cross-sectional oil pressure difference of the valve core. In the open state, because S3 > S2, the control valve core 4 is tightly pressed into the open position by the oil pressure. In the closed state, because S1 + S2 > S3, the control valve core 4 is tightly pressed into the closed position by the oil pressure.

[0056] In the initial stage of the repulsion disk 14's operation, a large repulsion force acts on the repulsion disk 14. In the final stage of the repulsion disk 14's movement, in order to reduce the impact of the valve core on the valve port, the repulsion disk 14 only drives the control valve core 4 to move a large part of the stroke. At this time, the A2 piston 42 disengages from the left valve core seat 2, the variable oil port Z is low-pressure oil, and the A1 chamber is connected to the variable oil port Z. At this time, since S3 > S2, the resultant force on the control valve core 4 is to the right, thereby pushing the control valve core 4 to move the remaining small part of the stroke. This structure can shorten the mechanism start-up time to within 4ms and reduce the mechanical impact between the valve core and the valve core seat sealing part inside the control valve, greatly improving the service life of the control valve.

[0057] Of course, the above description is not limited to the examples above. Technical features of this utility model not described can be implemented by or using existing technology, and will not be repeated here. The above embodiments and drawings are only used to illustrate the technical solution of this utility model and are not intended to limit this utility model. This utility model has been described in detail with reference to preferred embodiments. Those skilled in the art should understand that any changes, modifications, additions or substitutions made by those skilled in the art within the scope of this utility model do not depart from the spirit of this utility model and should also fall within the protection scope of the claims of this utility model.

Claims

1. A dual-control system for a hydraulic operating mechanism of a fast circuit breaker, characterized in that: The system includes a control valve assembly and an electromagnetic repulsion trip assembly. The control valve assembly includes a control valve seat (1) and a control valve core (4). The electromagnetic repulsion trip assembly includes a trip assembly frame (10) and a central connecting rod (11) that slides along the moving direction of the control valve core (4) within the trip assembly frame. The central connecting rod (11) pulls the control valve core (4) to the right to achieve rapid tripping. The control valve seat (1) has a low-pressure oil port (T), a variable oil port (Z), and a high-pressure oil port (P) arranged from left to right. The control valve seat (1) has a left valve core seat (2) and a right valve core seat (3) that are fixed inside the control valve seat (1) and wrapped around the left and right ends of the control valve core (4). The control valve core (4) has an A3 piston (43), an A2 piston (42), and an A1 piston (41) fixed in sequence. The left side of the A3 piston (43) and the left valve core seat (2) form the A3 cavity. The right side of piston A1 (41) and the right valve core seat (3) form chamber A1. The right side of piston A2 (42) and the left side of piston A3 (43) are connected through a connecting hole (44). When the circuit is open, the right side of piston A2 (42) and the right valve core seat (3) form chamber A2 and the chamber A2 is connected to the high pressure port (P). The control valve seat (1) is equipped with an oil circuit switching valve (8). The two ends of the oil circuit switching valve (8) are connected to chamber A1 and variable port (Z) respectively. When the central connecting rod (11) pulls the control valve core (4) to the right to achieve rapid circuit opening, the oil circuit switching valve (8) is opened through the connecting rod assembly (9), so that the oil in chamber A1 enters the variable port (Z).

2. The dual-control system for the hydraulic operating mechanism of a fast circuit breaker according to claim 1, characterized in that: The left end of the central connecting rod (11) is fixedly connected to a connector (12), and the connector (12) has a cavity inside. The right end of the control valve core (4) is fixedly connected to a boss (13) located in the cavity.

3. The dual-control system for the hydraulic operating mechanism of a fast circuit breaker according to claim 2, characterized in that: The release assembly frame (10) is fixedly connected to an oil buffer (16) located on the right side of the central connecting rod (11). The oil buffer (16) is provided with a reset spring.

4. The dual-control system for the hydraulic operating mechanism of a fast circuit breaker according to claim 2, characterized in that: The linkage assembly (9) includes a fixed mounting block (94) and a crank arm (92) hinged on the mounting block (94). A push rod (93) is provided between the crank arm (92) and the oil circuit switching valve (8). One end of the push rod (93) is hinged to the mounting block (94), and one end of the crank arm (92) is connected to the connector (12) through the pull rod (91). When the central linkage (11) performs a rapid opening to the right, the pull rod (91) drives the upper end of the crank arm (92) to swing to the right, and the lower end of the crank arm (92) swings to the left and pushes the push rod (93) to swing to the left to open the oil circuit switching valve (8).

5. A dual-control system for a hydraulic operating mechanism of a fast circuit breaker according to claim 4, characterized in that: One end of the pull rod (91) is hinged to the crank arm (92), and the other end is hinged to the connector (12).

6. The dual-control system for the hydraulic operating mechanism of a fast circuit breaker according to claim 4, characterized in that: The oil circuit switching valve (8) includes a switching valve seat (81) and a switching valve core (84). The switching valve seat (81) has an inlet (82), an outlet (83), and an oil passage connecting the inlet (82) and the outlet (83). The switching valve seat (81) contains a steel ball (85) and a compression spring (87) that drives the steel ball (85) to block the oil passage. When the push rod (93) swings to the left, it presses the switching valve core (84). The switching valve core (84) pushes open the steel ball (85) to achieve the connection between the inlet (82) and the outlet (83).

7. The dual-control system for the hydraulic operating mechanism of a fast circuit breaker according to claim 1, characterized in that: The control valve assembly also includes a trip solenoid valve (6) that controls the control valve core (4) to move to the right to achieve tripping, and a closing solenoid valve (5) that controls the control valve core (4) to move to the left to achieve closing. The closing solenoid valve (5) is connected to the high-pressure oil port (P) and the A1 chamber, and the trip solenoid valve (6) is connected to the low-pressure oil port (T) and the A1 chamber. The pressure-bearing cross-sectional areas of pistons A3 (43), A2 (42) and A1 (41) are S3, S2 and S1, respectively, and S1 < S2 < S3, S1 + S2 > S3.

8. A dual-control system for a hydraulic operating mechanism of a fast circuit breaker according to claim 7, characterized in that: When the circuit breaker is quickly tripped, the central connecting rod (11) pulls the control valve core (4) to move a certain distance. Then, the control valve core (4) continues to move to the right through the oil pressure difference between the pressure-bearing cross-sectional areas S3 and S2 to achieve quick tripping.

9. A dual-control system for a hydraulic operating mechanism of a fast circuit breaker according to claim 7, characterized in that: The trip solenoid valve (6) has two parts, which are respectively connected to the low-pressure oil port (T) and the A1 chamber.

10. A dual-control system for a hydraulic operating mechanism of a fast circuit breaker according to claim 1, characterized in that: Two repulsion disks (14) are fixedly connected to the central connecting rod (11), and two trip coils (15) are fixedly connected to the body of the trip assembly frame, located to the left of the two repulsion disks (14).

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