High-voltage direct-current contactor with anti-short-circuit structure

Abstract

The utility model discloses a high-voltage direct current contactor with an anti-short circuit structure, which relates to the technical field of contactors, and comprises a shell, a movable contact structure and an anti-short circuit structure, an accommodating cavity is formed in the shell, a static contact part is arranged on one inner side wall of the shell, a support is arranged on one side opposite to the static contact part, and the movable contact structure is arranged in the accommodating cavity. The movable contact structure comprises a push rod assembly and a movable contact part arranged at the movable end of the push rod assembly, the movable contact part can abut against or be separated from the static contact part, and the anti-short-circuit structure comprises a first magnetic conductive piece and a second magnetic conductive piece which are arranged on the support and the movable contact part respectively; in the technical scheme provided by the utility model, short-circuit large current causes the static contact part and the movable contact part to generate repulsive force, the attraction force generated by the first magnetic conductive piece and the second magnetic conductive piece can counteract the repulsive force generated by the short-circuit large current, and the attraction force can act on the bracket and is transmitted to the shell through the bracket, so that the structural stability and reliability are high; and a high-power-consumption coil does not need to be adopted.

Description

Technical Field

[0001] This utility model relates to the field of contactor technology, and in particular to a high-voltage DC contactor with a short-circuit protection structure. Background Technology

[0002] High-voltage DC contactors, as electrical devices for long-distance connection and disconnection of DC circuits, feature large control capacity, suitability for frequent operation, and remote intelligent control. They play a vital role in power systems and are widely used in solar energy systems, urban rail transit, subways, charging piles, energy storage battery packs, uninterruptible power supplies, and the communications industry. High-voltage DC contactors can withstand voltages of several thousand volts or even higher without breakdown or flashover, and can carry or disconnect currents of several hundred to several thousand amperes. The contact components are specially designed to ensure long lifespan and reliability under frequent operation and extreme working conditions. Furthermore, high-voltage DC contactors are small in size and light in weight, facilitating transportation, installation, and maintenance, reducing downtime and maintenance costs, thereby ensuring safe, efficient, and reliable power transmission.

[0003] The short-circuit protection structure of a high-voltage DC contactor is a specialized design to keep the contacts closed under high-current short-circuit conditions, preventing them from being repelled by electrodynamic repulsion. This structure typically includes a reinforced magnetic circuit system, such as upper and lower magnetic blocks, and possibly other auxiliary components, such as short-circuit protection coils or special core designs. These components work together to provide additional attraction during a short circuit to counteract the electrodynamic repulsion between the contacts, ensuring the contactor's stability and circuit continuity. This design is crucial for improving the reliability and safety of high-voltage DC contactors under extreme operating conditions.

[0004] To control the air gap between the upper and lower magnetic blocks, both blocks are often designed onto the push rod. Under short-circuit high-current conditions, the magnetic blocks experience additional attraction because the magnetic field generated when the current passes through them enhances the magnetic attraction. To maintain the closed state of the contacts, the coil needs to provide greater holding force to overcome this enhanced attraction. This necessitates increasing coil power consumption or modifying the core structure to increase the holding force, thus increasing the equipment cost. Utility Model Content

[0005] The main purpose of this invention is to propose a high-voltage DC contactor with a short-circuit protection structure, which aims to reduce the holding force of the coil on the iron core, thereby reducing the coil power consumption.

[0006] To achieve the above objectives, this utility model proposes a high-voltage DC contactor with a short-circuit protection structure, comprising:

[0007] The outer casing has a receiving cavity, and a static contact portion is provided on one inner side wall of the outer casing. A bracket is provided on the side opposite to the static contact portion.

[0008] A dynamic contact structure, comprising a push rod assembly and a dynamic contact portion disposed at the movable end of the push rod assembly, the dynamic contact portion being capable of abutting against or disengaging from the static contact portion; and

[0009] The short-circuit protection structure includes a first magnetic conductive element and a second magnetic conductive element. One of the first magnetic conductive elements is disposed on the bracket, and the other is disposed on the moving contact portion. The first magnetic conductive element and the second magnetic conductive element are disposed opposite to each other.

[0010] In one embodiment, the bracket includes two spaced-apart vertical plates and a horizontal plate connecting the ends of the two vertical plates, the two vertical plates being disposed on the outer casing;

[0011] The horizontal plate has a snap-fit ​​groove on the side facing the moving contact part. The first magnetic conductive element is a magnetic block. The magnetic block is snapped into the snap-fit ​​groove and integrally formed with the bracket by coating.

[0012] In one embodiment, the inner peripheral wall of the snap-fit ​​groove is provided with a limiting groove, and the outer peripheral wall of the magnetic block is provided with a limiting protrusion, the limiting protrusion being snap-fitted into the limiting groove.

[0013] In one embodiment, the outer shell includes an upper shell and a yoke plate covering the opening of the upper shell, two vertical plates are disposed on the yoke plate, and the movable contact portion is disposed between the horizontal plate and the yoke plate.

[0014] In one embodiment, the push rod assembly includes:

[0015] A push rod, which is movably mounted on the yoke plate; and

[0016] A push plate is provided at one end of the push rod near the stationary contact portion. The push plate is provided with a fixed frame, and the moving contact portion is movably provided on the push plate and located within the fixed frame.

[0017] The second magnetic conductive component is a U-shaped magnetic conductive plate, which is disposed at the moving contact portion.

[0018] In one embodiment, the fixing frame has two limiting notches, and the two ends of the U-shaped magnetic guide plate are slidably disposed in the limiting notches and are positioned toward the first magnetic guide member.

[0019] In one embodiment, the push plate is provided with an elastic element facing the fixed frame, the U-shaped magnetic guide plate is disposed on the elastic element, and the moving contact portion is disposed on the side of the U-shaped magnetic guide plate facing the stationary contact portion.

[0020] In one embodiment, the high-voltage DC contactor with short-circuit protection structure includes two sets of stationary contacts and two sets of moving contacts. Each set of stationary contacts includes two stationary contacts, and each set of moving contacts includes one moving contact. Every two stationary contacts cooperate with one moving contact.

[0021] An auxiliary contact is provided between the two sets of static contact parts, and a conductive piece is provided between the two sets of dynamic contact parts opposite to the auxiliary contact.

[0022] In one embodiment, the high-voltage DC contactor with short-circuit protection structure further includes an insulating sleeve, which is sleeved on the conductive piece and located between the two sets of moving contacts;

[0023] The horizontal plate is provided with two spaced-apart slots, and each magnetic block is provided with one slot.

[0024] In one embodiment, the horizontal plate is provided with a mounting groove, which is located between the two snap-fit ​​grooves, and the horizontal plate is snap-fitted and limited to the insulating sleeve through the mounting groove.

[0025] The present invention proposes a high-voltage DC contactor with a short-circuit protection structure, comprising a housing, a moving contact structure, and a short-circuit protection structure. The housing has a cavity, and a stationary contact portion is provided on one inner side wall of the housing. A bracket is provided on the side opposite the stationary contact portion. The short-circuit protection structure includes a first magnetic conductor and a second magnetic conductor, which are respectively disposed on the side of the bracket facing the moving contact portion and the side of the moving contact portion facing the bracket. When a large short-circuit current causes the stationary contact portion and the moving contact portion to repel each other, the first magnetic conductor on the bracket will generate an attractive force with the second magnetic conductor disposed opposite to it to cancel the repulsive force generated by the stationary contact portion and the moving contact portion. The attractive force will act on the bracket and be transmitted to the housing through the bracket. The structure has high stability and reliability, and there is no need to use a high-power coil. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0027] Figure 1 A schematic diagram of the internal structure of an embodiment of a high-voltage DC contactor with a short-circuit protection structure provided by this utility model;

[0028] Figure 2A schematic diagram of the external structure of a high-voltage DC contactor with short-circuit protection;

[0029] Figure 3 A cross-sectional view of a high-voltage DC contactor with a short-circuit protection structure provided by this utility model;

[0030] Figure 4 for Figure 3 A magnified view of a section at point A in the middle;

[0031] Figure 5 for Figure 1 Schematic diagram of the mid-support structure;

[0032] Figure 6 This is a schematic diagram of the magnetic conductive block.

[0033] Explanation of icon numbers:

[0034] 100. High-voltage DC contactor with short-circuit protection structure; 1. Housing; 11. Upper housing; 111. Static contact part; 112. Auxiliary contact; 12. Yoke plate; 2. Push rod assembly; 21. Push plate; 211. Moving contact part; 212. Elastic element; 22. Push rod; 3. Short-circuit protection structure; 31. Magnetic guide block; 311. Limiting protrusion; 32. U-shaped magnetic guide plate; 321. Limiting protrusion; 4. Bracket; 41. Vertical plate; 42. Horizontal plate; 421. Mounting groove; 422. Snap-fit ​​groove; 423. Limiting groove; 5. Insulating sleeve; 6. Drive mechanism.

[0035] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0036] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0037] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0038] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0039] This invention proposes a high-voltage DC contactor with a short-circuit protection structure, aiming to reduce the holding force of the coil on the iron core, thereby reducing coil power consumption. Figures 1 to 6 This is a schematic diagram of an embodiment of the high-voltage DC contactor with short-circuit protection structure provided by this utility model.

[0040] Please refer to Figures 1 to 6 This utility model proposes a high-voltage DC contactor 100 with a short-circuit protection structure, including a housing 1, a moving contact structure, and a short-circuit protection structure 3. The housing 1 forms a cavity, and a stationary contact portion 111 is provided on one inner side wall of the housing 1. A bracket 4 is provided on the opposite side of the stationary contact portion 111. The moving contact structure includes a push rod assembly 2 and a moving contact portion 211 provided at the movable end of the push rod assembly 2. The moving contact portion 211 can abut or disengage from the stationary contact portion 111. The short-circuit protection structure 3 includes a first magnetic conductive element and a second magnetic conductive element. One of the first magnetic conductive elements is provided on the bracket 4, and the other is provided on the moving contact portion 211. The first magnetic conductive element and the second magnetic conductive element are arranged opposite to each other.

[0041] The present invention proposes a high-voltage DC contactor 100 with a short-circuit protection structure, comprising a housing 1, a moving contact structure, and a short-circuit protection structure 3. The housing 1 forms a cavity, and a stationary contact portion 111 is provided on one inner side wall of the housing 1. A bracket 4 is provided on the opposite side of the stationary contact portion 111. The short-circuit protection structure 3 includes a first magnetic conductive element and a second magnetic conductive element. The first magnetic conductive element and the second magnetic conductive element are respectively disposed on the side of the bracket 4 facing the moving contact portion 211 and the side of the moving contact portion 211 facing the bracket 4. When a large short-circuit current causes the stationary contact portion 111 and the moving contact portion 211 to generate a repulsive force, the first magnetic conductive element disposed on the bracket 4 will generate an attractive force with the second magnetic conductive element disposed opposite to it to counteract the repulsive force generated by the stationary contact portion 111 and the moving contact portion 211. The attractive force will act on the bracket 4 and be transmitted to the housing 1 through the bracket 4. The structure has high stability and reliability, and there is no need to use a high-power coil.

[0042] The support 4 is shaped like an inverted U. For details, please refer to further documentation. Figure 2 The bracket 4 consists of two parallel, spaced vertical plates 41 and a horizontal plate 42 connecting the ends of the two vertical plates 41. The bracket 4 has a simple structure but provides a stable and rigid support frame, making it less prone to deformation under strong suction. In this embodiment, a first magnetic conductor is located on the bracket 4, and correspondingly, a second magnetic conductor is located on the moving contact portion 211. To fix the first magnetic conductor, the horizontal plate 42 of the bracket 4 has a locking groove 422 on the side facing the moving contact portion 211. For more details, please refer to further reference. Figure 5 The first magnetic conductive component is a magnetic block 31, which is flat in shape. The magnetic conductive component can be fixed in the snap-fit ​​groove 422 of the horizontal plate 42 by snap-fit ​​or by adhesive bonding; this invention does not limit this method. In one embodiment of this invention, since the bracket 4 needs to maintain good insulation performance, high-molecular materials with certain structural strength, such as epoxy resin, polyethylene, and ceramics, are preferentially selected during the manufacturing process of the bracket 4. To ensure the installation strength of the magnetic conductive component on the bracket 4, the magnetic conductive component is fixed integrally with the bracket 4 by rubber coating. Rubber coating is a process of wrapping rubber or plastic material around the surface of a metal part to provide additional support, insulation, or improve structural strength. Rubber coating can enhance the durability and safety of the product, and also improve the connection strength between the bracket 4 and the magnetic block 31.

[0043] Furthermore, the magnetic block 31 is provided with limiting protrusions 311 around its perimeter. For details, please refer to further documentation. Figure 6 When the bracket 4 is fixed to the outer periphery of the magnetic block 31 by the adhesive coating, a limiting groove 423 matching the limiting protrusion 311 will be formed. Each limiting protrusion 311 is engaged with a limiting groove 423. The limiting protrusion 311 is set close to the bottom of the engaging groove 422, so as to prevent the magnetic block 31 from coming out of the opening of the engaging groove 422.

[0044] In one embodiment of this utility model, the outer shell 1 includes an upper shell 11 and a yoke plate 12 covering the opening of the upper shell 11. The two vertical plates 41 of the bracket 4 are connected to the yoke plate 12 at the ends away from the horizontal plate 42. It should be noted that the bracket 4 can be fixed to the yoke plate 12 by snap-fitting, such as by providing multiple snap-fitting parts on the yoke plate 12, which are snap-fitting and limiting the bracket 4 to the side wall of the vertical plate 41. Alternatively, the bracket 4 can be installed on the yoke plate 12 by adhesive bonding. This utility model does not limit the scope of the invention. In one embodiment of this utility model, the bracket 4 is fixed to the yoke plate 12 by adhesive bonding. Adhesive bonding eliminates the need for snap-fitting structures at the ends of the yoke plate 12 and the vertical plates 41, which is more conducive to the simplification of the structure.

[0045] In another embodiment of this utility model, the yoke plate 12 is provided with an insulating sleeve 5 for isolating the auxiliary contact part. The insulating sleeve 5 has an installation notch in the middle position. Correspondingly, the bracket 4 is provided with an installation groove 421. The bracket 4 is fixed by engaging with the installation notch on the insulating sleeve 5 through the installation groove 421. In this way, the ends of the two vertical plates 41 on the bracket 4 that are in contact with the yoke plate 12 can be fixed to the yoke plate 12 without being snapped or glued. The two vertical plates 41 naturally abut against the yoke plate 12. When the magnetic block 31 on the bracket 4 is attracted by the U-shaped magnetic plate below, it will transfer the force to the two vertical plates 41 and then to the yoke plate 12. Alternatively, the force can be transferred to the insulating sleeve 5 and then to the yoke plate 12. The structure has high reliability.

[0046] The second magnetic conductor in this contactor is mounted on the push plate 21 and moves along the same path as the moving contact portion 211 on the push plate 21. When the second magnetic conductor is subjected to the magnetic repulsion force of the magnetic block 31 mounted on the bracket 4, since the moving contact portion 211 moves synchronously with the second magnetic conductor, it will move towards the end away from the bracket 4. This separates the moving contact portion 211 from the stationary contact portion 111 by the repulsive force and prevents the moving contact portion 211 from jumping. In this embodiment, the second magnetic conductor is a U-shaped magnetic plate. For details, please refer to further reference. Figure 4 The U-shaped magnetic plate has a groove for accommodating the movable contact 211, which is fixed in the groove. Both ends of the U-shaped magnetic plate are positioned towards the magnetic block 31 and protrude through the fixing frame to be exposed on the top surface of the fixing frame. This ensures that the repulsive force generated between the magnetic block 31 and the U-shaped magnetic plate is not isolated or weakened by the fixing frame.

[0047] The high-voltage DC contactor 100 with short-circuit protection also includes a resilient element 212; for details, please refer to further details. Figure 3 and Figure 4 The elastic element 212 has push plate 21 and moving contact part 211 connected to its two ends respectively, allowing the moving contact part 211 to move relative to push rod 22. The soft contact between the moving contact part 211 and the stationary contact part 111 achieved through the elastic element 212 reduces the impact force on the moving contact part 211 during closure, lowers contact resistance, thereby reducing arc generation and extending the contactor's service life. Simultaneously, the soft contact helps reduce mechanical wear, improves contact reliability, and ensures stable connection under high-voltage conditions. Furthermore, the buffering effect of the elastic element 212 can absorb minor displacements caused by vibration or thermal expansion, maintaining the continuity and consistency of the contact. One end of the elastic element 212 is connected to the back of the U-shaped magnetic guide plate, which has a limiting protrusion 321. The two ends of the elastic element 212 are fixed to the limiting protrusion 321 and push plate 21 respectively.

[0048] In one embodiment of this utility model, the high-voltage DC contactor 100 with a short-circuit protection structure adopts a double-group contact layout, including two groups of stationary contacts 111 and two groups of moving contacts 211. Each group of stationary contacts 111 includes two stationary contacts 111, and each group of moving contacts 211 includes one moving contact 211. Every two stationary contacts 111 cooperate with one moving contact 211. In addition, an auxiliary contact is provided between the two groups of stationary contacts 111, and a conductive piece is provided between the two groups of moving contacts 211 opposite to the auxiliary contact. An insulating sleeve 5 is sleeved on the conductive piece. The purpose of the auxiliary contacts and conductive plates is to prevent the moving contact 211 and the two stationary contacts 111 from sticking together after closing. When the push rod 22 pushes the arc-blocking structure downward, the conductive plates on the arc-blocking structure will also move downward together until the two ends of the conductive plates contact the two auxiliary contacts respectively. The verification circuit is turned on. At this time, the moving contact 211 and the two stationary contacts 111 of the high-voltage DC contactor 100 with short-circuit protection structure are also in contact, and the contactor is closed. If the moving contact 211 and the two stationary contacts 111 stick together after closing, the verification circuit will always be in a conductive state. When the preset alarm time is reached, the verification circuit will alarm or use other means to directly cut off the connection between the moving contact 211 and the auxiliary contacts, thereby ensuring the safety of the equipment.

[0049] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A high-voltage DC contactor with a short-circuit protection structure, characterized in that, include: The outer casing has a receiving cavity, and a static contact portion is provided on one inner side wall of the outer casing. A bracket is provided on the side opposite to the static contact portion. A dynamic contact structure, the dynamic contact structure including a push rod assembly and a dynamic contact portion disposed at the movable end of the push rod assembly, the dynamic contact portion being able to abut or disengage from the static contact portion; as well as The short-circuit protection structure includes a first magnetic conductive element and a second magnetic conductive element. One of the first magnetic conductive elements is disposed on the bracket, and the other is disposed on the moving contact portion. The first magnetic conductive element and the second magnetic conductive element are disposed opposite to each other.

2. The high-voltage DC contactor with short-circuit protection structure as described in claim 1, characterized in that, The bracket includes two spaced vertical plates and a horizontal plate connecting the ends of the two vertical plates, with the two vertical plates disposed on the outer shell; The horizontal plate has a snap-fit ​​groove on the side facing the moving contact part. The first magnetic conductive element is a magnetic block. The magnetic block is snapped into the snap-fit ​​groove and integrally formed with the bracket by coating.

3. The high-voltage DC contactor with short-circuit protection structure as described in claim 2, characterized in that, The inner peripheral wall of the snap-fit ​​groove is provided with a limiting groove, and the outer peripheral wall of the magnetic block is provided with a limiting protrusion. The limiting protrusion is snap-fitted into the limiting groove.

4. The high-voltage DC contactor with short-circuit protection structure as described in claim 2, characterized in that, The outer shell includes an upper shell and a yoke plate covering the opening of the upper shell. The two vertical plates are disposed on the yoke plate, and the moving contact portion is disposed between the horizontal plate and the yoke plate.

5. The high-voltage DC contactor with short-circuit protection structure as described in any one of claims 1 to 4, characterized in that, The push rod assembly includes: A push rod, which is movably mounted on the yoke plate; and A push plate is provided at one end of the push rod near the stationary contact portion. The push plate is provided with a fixed frame, and the moving contact portion is movably provided on the push plate and located within the fixed frame. The second magnetic conductive component is a U-shaped magnetic conductive plate, which is disposed at the moving contact portion.

6. The high-voltage DC contactor with short-circuit protection structure as described in claim 5, characterized in that, The fixing frame has two limiting notches, and the two ends of the U-shaped magnetic guide plate are slidably disposed in the limiting notches and are positioned toward the first magnetic guide component.

7. The high-voltage DC contactor with short-circuit protection structure as described in claim 6, characterized in that, The push plate is provided with an elastic element facing the fixed frame, the U-shaped magnetic guide plate is provided on the elastic element, and the moving contact part is provided on the side of the U-shaped magnetic guide plate facing the static contact part.

8. The high-voltage DC contactor with short-circuit protection structure as described in claim 2, characterized in that, The high-voltage DC contactor with short-circuit protection structure includes two sets of stationary contacts and two sets of moving contacts. Each set of stationary contacts includes two stationary contacts, and each set of moving contacts includes one moving contact. Every two stationary contacts cooperate with one moving contact. An auxiliary contact is provided between the two sets of static contact parts, and a conductive piece is provided between the two sets of dynamic contact parts opposite to the auxiliary contact.

9. The high-voltage DC contactor with short-circuit protection structure as described in claim 8, characterized in that, The high-voltage DC contactor with short-circuit protection structure also includes an insulating sleeve, which is sleeved on the conductive piece and located between the two sets of moving contact portions; The horizontal plate is provided with two spaced-apart slots, and each magnetic block is provided with one slot.

10. The high-voltage DC contactor with short-circuit protection structure as described in claim 9, characterized in that, The horizontal plate is provided with an installation groove, which is located between the two snap-fit ​​grooves. The horizontal plate is snap-fitted and limited to the insulating sleeve through the installation groove.

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