Semi-self-driven current limiting device for short-circuit current

Abstract

The utility model discloses a short-circuit current semi-self-driven current limiting device which is arranged in a sealed shell structure through a support and comprises an eddy current repulsive force mechanism, an energy taking CT, a spring, a central insulation pull rod, a vacuum arc-extinguishing chamber and a current limiting reactor which are connected in sequence, and the eddy current repulsive force mechanism, the energy taking CT, the spring, the central insulation pull rod and the vacuum arc-extinguishing chamber are connected with the current limiting reactor. The energy-taking CT is arranged on the central insulating pull rod in a sleeving manner and is connected with the vacuum arc-extinguishing chamber; the central insulating pull rod is connected with the eddy current repulsion mechanism; the bottom of the spring is fixed on the support, the top of the spring supports the center insulation pull rod, and the eddy current repulsive force mechanism is matched with the center insulation pull rod in the motion state of the spring to control switching separation and connection of the high-voltage electrified body and the low-voltage electrified body. According to the utility model, the lengthened insulating pull rod is adopted to isolate a primary electrification part from a secondary control part, so that the primary and secondary separation design is realized, and the interference of the secondary control part is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of power supply and distribution of electric power systems, in particular to a short-circuit current semi-self-driven current limiting device. Background Art

[0002] With the stable operation of the power system and the connection of large equipment to the grid, short-circuit current exceeds the standard from time to time. In order to solve this kind of problem, series current limiting reactors are generally used to solve it. However, series current limiting reactors will bring about a series of problems such as increased energy consumption, electromagnetic interference, and voltage drop.

[0003] With the advancement of technology, the mode of fast-switching shunt reactor is generally adopted to avoid the disadvantages of conventional series current-limiting reactors. Due to its advantages of good current-limiting effect, low cost and high reliability, it has become a highly feasible solution. At the same time, this method also brings about an integrated structure of the current-limiting primary body and secondary body, and anti-interference measures need to be taken in the control part to avoid false operation of the fast switch.

[0004] To this end, the present application proposes a short-circuit current semi-self-driven current limiting device to solve the above technical problems. Utility Model Content

[0005] The main purpose of the utility model is to provide a short-circuit current semi-self-driven current limiting device. The control device controls the energy storage element to achieve rapid opening, and the current limiting reactor is put into use to achieve the purpose of current limiting. When the short-circuit current disappears, the bottom spring and the closing permanent magnet, the self-closing force of the vacuum switch and other elements are used to achieve rapid closing of the switch, exit the reactor, and restore normal operating state to solve the above technical problems.

[0006] In order to solve the above technical problems, the utility model provides a short-circuit current semi-self-driven current limiting device, which is arranged in a sealed housing structure through a bracket, including an eddy current repulsion mechanism, an energy-taking CT, a spring, a central insulating pull rod, a vacuum interrupter and a current-limiting reactor, wherein the central insulating pull rod, the vacuum interrupter and the current-limiting reactor are connected in sequence, the energy-taking CT is sleeved on the central insulating pull rod and connected to the vacuum interrupter, and the central insulating pull rod is connected to the eddy current repulsion mechanism;

[0007] The bottom of the spring is fixed on the bracket, and the top of the spring supports the central insulating pull rod. The eddy current repulsion mechanism cooperates with the central insulating pull rod in the spring movement state to control the switching separation and connection of the high-voltage charged body and the low-voltage charged body.

[0008] Furthermore, the eddy current repulsion mechanism includes an eddy current disk, an opening coil, an opening holding magnet, a closing permanent magnet and an armature, wherein:

[0009] The opening coil is suspended on the top of the eddy current disk and fixed on the bracket, the opening holding magnet is located on the upper part of the opening coil and fixed on the bracket, the armature is suspended above the opening holding magnet, and the closing permanent magnet is located above the armature.

[0010] Furthermore, it also includes current transformers arranged on both sides of the central insulating pull rod, and the current transformers are electrically connected to the energy-taking CT.

[0011] Furthermore, the sealed shell structure includes a bellows sleeve, a connecting shell one and a connecting shell two, the bellows sleeve is used to connect the connecting shell one and the connecting shell two, the connecting shell one is connected to the current limiting inductor, the eddy current repulsion mechanism is arranged in the connecting shell two, and the central insulating pull rod is movably arranged in the bellows sleeve.

[0012] Furthermore, a disc is provided at the bottom of the bellows sleeve, a support bracket is provided on the disc for supporting the vacuum interrupter, and the disc at the bottom is used for the central insulating pull rod to pass through and slide.

[0013] The beneficial effects of the present invention are as follows:

[0014] 1. The utility model uses an extended insulating pull rod to isolate the primary live part and the secondary control part, realizing a primary and secondary separation design and reducing interference in the secondary control part.

[0015] 2. The opening of the utility model adopts secondary control, which can realize the opening of any short-circuit current without adjusting the mechanical structure, and is more practical.

[0016] 3. The utility model adds a spring at the bottom of the quick switch to improve the reliability of the switch closing, and the structure is novel, simple and reliable.

[0017] 4. The utility model adopts the automatic driving of the short-circuit current to close the switch, thereby realizing the intelligent self-driving of the fault current limiting device. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings constituting part of this application are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0019] Figure 1 It is a front view cross-sectional plan view of the overall structure of the utility model;

[0020] Figure 2 for Figure 1 Magnified view at point A in the middle;

[0021] Figure 3 It is a side sectional plan view of the overall structure of the utility model;

[0022] Figure 4 It is a three-dimensional structural diagram of the overall structure of the utility model;

[0023] Figure 5 This is a front view cross-sectional plan view of the internal structure of the housing of the present invention;

[0024] Figure 6 It is a side view cross-sectional plan view of the internal structure of the shell of the utility model;

[0025] Figure 7 This is a schematic diagram of the principle circuit of the utility model in operation.

[0026] In the picture:

[0027] 1. Eddy current repulsion mechanism; 2. Eddy current disk; 3. Opening coil; 4. Disc; 5. Opening holding magnet; 6. Closing permanent magnet; 7. Energy taking CT; 8. Spring; 9. Center insulating pull rod; 10. Vacuum interrupter; 11. Current limiting reactor; 12. Armature; 13. Current transformer; 14. Support bracket; 15. Bellows sleeve; 16. Connecting shell 1; 17. Connecting shell 2. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0029] In the embodiment, see Figures 1 to 7 .

[0030] like Figure 1 As shown, the utility model provides a short-circuit current semi-self-driven current limiting device, which is arranged in a sealed housing structure through a bracket, including an eddy current repulsion mechanism 1, an energy taking CT 7, a spring 8, a central insulating rod 9, a vacuum interrupter 10 and a current limiting reactor 11. The central insulating rod 9, the vacuum interrupter 10 and the current limiting reactor 11 are connected in sequence. The energy taking CT 7 is sleeved on the central insulating rod 9 and connected to the vacuum interrupter 10. The central insulating rod 9 is connected to the eddy current repulsion mechanism 1;

[0031] The bottom of the spring 8 is fixed on the bracket, and the top of the spring 8 supports the central insulating pull rod 9. The eddy current repulsion mechanism 1 cooperates with the central insulating pull rod 9 in the movement state of the spring 8 to control the switching separation and connection of the high-voltage charged body and the low-voltage charged body.

[0032] By using an extended central insulating rod 9 in the circuit breaker design, physical isolation between the primary electrical components and the secondary control components is successfully achieved. This primary-secondary separation significantly reduces electromagnetic interference in the secondary control circuit, improving the stability and safety of system operation. Furthermore, by integrating a spring 8 at the bottom of the fast switch, the reliability and stability of the switch closing action are effectively improved. The addition of spring 8 not only provides the necessary driving force for the closing process, but also makes the entire structural design more simple and efficient, further strengthening the durability and operational reliability of the device.

[0033] Specifically, such as Figure 2 As shown, the eddy current repulsion mechanism 1 includes an eddy current disk 2, a tripping coil 3, a tripping holding magnet 5, a closing permanent magnet 6 and an armature 12, wherein:

[0034] The opening coil 3 is suspended on the top of the eddy current disk 2 and fixed on the bracket. The opening holding magnet 5 is located on the upper part of the opening coil 3 and fixed on the bracket. The armature 12 is suspended above the opening holding magnet 5. The closing permanent magnet 6 is located above the armature 12.

[0035] At this time, the discharge of the opening energy storage capacitor drives the eddy current disk to operate for the device to open, and the energy CT7 controls the electromagnet to attract the armature 12 for maintaining the opening. The closing of the device is achieved by the elastic force of the bottom spring 8, the suction force of the closing permanent magnet 6 and the self-closing force of the vacuum bubble.

[0036] At the same time, the invention also innovatively adopts a secondary control mechanism to perform the tripping operation, which means that no matter what the specific size of the short-circuit current is, the device can respond quickly and implement the tripping without the need to manually adjust any mechanical parameters, greatly enhancing the adaptability and practicality of the system and ensuring a rapid protection response of the power system.

[0037] In addition, it should be noted that this device has no closing drive coil. Closing relies on the self-closing force of the vacuum interrupter 10, and after closing, it is maintained by the closing permanent magnet 6; this device has an opening drive coil. Opening relies on the opening drive coil, and after opening, it is maintained by the opening holding electromagnet TB.

[0038] Further, such as Figure 3 As shown, the short-circuit current semi-self-driven current limiting device also includes current transformers 13 arranged on both sides of the central insulating pull rod 9. The current transformers 13 are electrically connected to the energy CT7 for rapid energy collection by the energy CT7.

[0039] Further, such as Figure 4As shown, the sealed shell structure includes a bellows sleeve 15, a connecting shell 16 and a connecting shell 2 17. The bellows sleeve 15 is used to connect the connecting shell 16 and the connecting shell 2 17. The connecting shell 16 is connected to the current limiting inductor 11. The eddy current repulsion mechanism 1 is arranged in the connecting shell 2 17, and the central insulating pull rod 9 is movably arranged in the bellows sleeve 15.

[0040] In addition, in one embodiment, reference Figure 5 and Figure 6 A disc 4 is provided at the bottom of the bellows sleeve 15, and a support bracket 14 is provided on the disc 4 for supporting the vacuum interrupter 10. The bottom disc 4 is used for the central insulating rod 9 to pass through and slide.

[0041] In the specific implementation process, refer to Figure 7 During normal operation, the rated current I n flows normally. When a short circuit occurs, the circuit breaker is quickly opened through the opening drive coil. After the opening is completed, the limited current I flowing through the reactor can maintain the opening position when passing through the TB coil. When the fault disappears and the operating current returns to the normal current I n, the TB holding force is reduced, and the circuit breaker is closed through the self-closing force of the vacuum interrupter 10. After closing, it is held by the closing holding magnet; at the same time, if the system short circuit fault is not removed within 2S, the main control unit sends a signal to trip the ZN series switch.

[0042] In summary, a self-driven fault current limiting system is constructed by utilizing the energy generated by the short-circuit current itself to drive the automatic closing function of the current limiting device. This design not only cleverly transforms the fault current that could otherwise cause damage into a source of power to activate the protection mechanism, but also effectively limits the fault current, fully demonstrating its intelligent and adaptive characteristics, greatly improving the efficiency and intelligence level of power system fault handling.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

[0044] In addition, it should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the various components in a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0045] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or schemes in which A and B are satisfied at the same time. In addition, in the embodiments of the present invention, "multiple" refers to more than two. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that ordinary technicians in this field can implement it. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. A short-circuit current semi-self-driven current limiting device, characterized in that: The device is arranged in a sealed housing structure through a bracket, and comprises an eddy current repulsion mechanism (1), an energy-taking CT (7), a spring (8), a central insulating pull rod (9), a vacuum interrupter (10), and a current-limiting reactor (11); the central insulating pull rod (9), the vacuum interrupter (10), and the current-limiting reactor (11) are connected in sequence; the energy-taking CT (7) is sleeved on the central insulating pull rod (9) and connected to the vacuum interrupter (10); and the central insulating pull rod (9) is connected to the eddy current repulsion mechanism (1); The bottom of the spring (8) is fixed on the bracket, and the top of the spring (8) supports the central insulating pull rod (9). When the spring (8) is in motion, the eddy current repulsion mechanism (1) cooperates with the central insulating pull rod (9) to control the switching separation and connection of the high-voltage charged body and the low-voltage charged body.

2. The short-circuit current semi-self-driven current limiting device according to claim 1, characterized in that: The eddy current repulsion mechanism (1) comprises an eddy current disk (2), a tripping coil (3), a tripping holding magnet (5), a closing permanent magnet (6) and an armature (12), wherein: The opening coil (3) is suspended on the top of the eddy current disk (2) and fixed on the bracket, the opening holding magnet (5) is located on the upper part of the opening coil (3) and fixed on the bracket, the armature (12) is suspended above the opening holding magnet (5), and the closing permanent magnet (6) is located above the armature (12).

3. The short-circuit current semi-self-driven current limiting device according to claim 1, characterized in that: It also includes current transformers (13) arranged on both sides of the central insulating pull rod (9), and the current transformers (13) are electrically connected to the energy-taking CT (7).

4. The short-circuit current semi-self-driven current limiting device according to claim 1, characterized in that: The sealed housing structure comprises a bellows sleeve (15), a connecting housing 1 (16) and a connecting housing 2 (17); the bellows sleeve (15) is used for connecting the connecting housing 1 (16) and the connecting housing 2 (17); the connecting housing 1 (16) is connected to the current-limiting inductor (11); the eddy current repulsion mechanism (1) is arranged in the connecting housing 2 (17); and the central insulating pull rod (9) is movably arranged in the bellows sleeve (15).

5. The short-circuit current semi-self-driven current limiting device according to claim 4, characterized in that: A disc (4) is provided at the bottom of the bellows sleeve (15), a support bracket (14) is provided on the disc (4) for supporting the vacuum interrupter (10), and the disc (4) at the bottom is used for the central insulating pull rod (9) to pass through and slide.

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