A high-breakage DC circuit breaker

Abstract

The present invention discloses a high-breakage DC circuit breaker, comprising two arc-extinguishing devices, two sets of moving contact assemblies, and two sets of static contact assemblies arranged in a housing structure. Each arc-extinguishing device is composed of two arc-extinguishing chambers. Each set of moving contact assemblies includes two moving contacts coaxially arranged on a rotating shaft and connected in parallel in the same polarity circuit. Each set of static contact assemblies includes two static contacts formed by a static conductive plate and accommodated in arc-guiding channels of the two arc-extinguishing chambers. The two moving contacts are respectively inserted into the two arc-extinguishing chambers to cooperate with the two static contacts. The core of this dual-contact synchronous action and the synergistic effect of the dual arc-extinguishing chambers is to reduce the loss rate of a single set of contacts / arc-extinguishing chambers and extend their service life by sharing current and arc energy. By rationally optimizing the housing space and the moving contact structure, the internal transmission, contacts, arc-extinguishing and other systems of the circuit breaker are made more stable, thereby enhancing the overall mechanical and electrical performance reliability and improving the breaking capacity of the DC circuit breaker.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit breakers, and in particular to a high-breaking DC circuit breaker. Background Art

[0002] With the vigorous development of new energy industry, rail transportation, photovoltaic, DC transmission and distribution and communication power supply industry, carbon economy has become the general trend of global economic development, and DC circuit breakers account for an increasingly larger share of the traditional power distribution market.

[0003] Traditional DC circuit breakers on the market are often based on traditional AC molded case circuit breakers with slight modifications and are directly applied to DC power distribution systems. In existing DC power distribution systems, the rated operating voltage of low-voltage electrical equipment is as high as DC1000V-1500V. These DC molded case circuit breakers cannot meet the needs of the new energy industry. To improve the breaking performance of DC circuit breakers currently developed for DC power distribution systems, they use two sets of contacts connected in series to form a dual-breakpoint contact structure, which is used to share arc energy and achieve arc extinguishing, thus meeting the requirements of existing DC power distribution systems. For example, Chinese patent document CN116403866A discloses a parallel double-contact DC circuit breaker, including a circuit breaker housing and internal components; the internal components include a front wiring port, a thermal-magnetic release, a contact structure, an arc extinguishing chamber, an arc channel and a rear wiring port arranged in sequence; the contact structure is a U-shaped double contact, and the U-shaped double contact includes two U-shaped moving contacts connected to two arc extinguishing chambers. The parallel U-shaped double contacts are fixed on the rotating shaft through a linkage shaft so as to be rotatable left and right. In combination with the drawings in the document, it can be clearly seen that the handle and operating mechanism of the circuit breaker are non-centrally arranged on one of the poles to drive the rotating shaft to rotate. This DC circuit breaker uses a parallel U-shaped double contact structure to realize double breakpoints in series within the same pole of the circuit breaker. However, as can be seen from the structure of the above-mentioned DC circuit breaker, it still has the following problems: 1. This U-shaped double contact is fixed to the rotating shaft by connecting parts such as a linkage shaft. The contact area is small and easily heats up. The connection is not reliable enough, which can easily cause one side of the two moving contacts to be higher than the other side. Asynchronous contact can easily cause contact burns, shorten the service life of the contacts, and affect the breaking capacity of the DC circuit breaker; 2. The non-centered operating mechanism can cause the rotating shaft to be unevenly stressed and deflected, resulting in unbalanced rotation. In addition, the electric repulsive force on the other pole contact will aggravate the shaft deflection, thereby damaging the mechanism and the rotating shaft. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the problems in the prior art where the U-shaped double contacts are fixed to the rotating shaft by connecting parts, resulting in a small contact area, easy heat generation, unreliable connection, shortened contact service life, and affected breaking capacity of the DC circuit breaker; thereby providing a high-breaking DC circuit breaker that reasonably optimizes the shell space and moving contact structure, enhances the overall mechanical and electrical performance reliability, and improves the product's breaking capacity in the power distribution system.

[0005] In order to solve the above technical problems, the present invention provides a high-breakage DC circuit breaker, comprising a two-pole electrical contact system, a two-pole arc extinguishing system and an operating mechanism arranged in a housing structure;

[0006] The housing structure includes two first compartments spaced apart from each other, and two second compartments spaced apart from the two first compartments in front and back, a guide port being provided between the first compartments and the second compartments, and the operating mechanism being centrally disposed in the housing structure and located between the two first compartments;

[0007] The two-pole arc extinguishing system includes two arc extinguishing devices arranged in two second compartments; each arc extinguishing device includes two arc extinguishing chambers arranged at intervals, one of the arc extinguishing chambers is arranged opposite to the guide port, and the other arc extinguishing chamber is arranged staggered with the guide port;

[0008] The two-pole electrical contact system includes a rotating shaft driven by an operating mechanism and arranged in a shell structure, two groups of movable contact components connected to the rotating shaft and arranged in two first compartments, and two groups of static contact components arranged in two second compartments; each group of movable contact components includes two movable contacts coaxially arranged on the rotating shaft and connected in parallel in the same pole circuit, and each group of static contact components includes a static conductive plate arranged under two arc extinguishing chambers and two static contacts formed by the static conductive plate and located in the arc guide channels of the two arc extinguishing chambers. The two movable contacts are respectively inserted into the arc guide channels of the two arc extinguishing chambers to cooperate with the two static contacts, and one of the movable contacts extends into one of the arc extinguishing chambers in a bent structure after passing through the guide opening.

[0009] In the above-mentioned high-breakdown DC circuit breaker, a movable arc-isolating structure is provided on the two moving contacts for preventing the arc from spreading from the two arc-extinguishing chambers to the side of the guide port. The movable arc-isolating structure includes a first arc-isolating sleeve commonly sleeved on the two moving contacts at the guide port, and two second arc-isolating sleeves branched from the first arc-isolating sleeve and extending from the guide port to the two arc-extinguishing chambers. The two second arc-isolating sleeves are respectively sleeved on the contact parts of the two moving contacts extending out of the guide port.

[0010] In the above-mentioned high-breakdown DC circuit breaker, each group of static contact assemblies is provided with a static arc-isolating structure for preventing the arc from spreading from the two arc-extinguishing chambers to one side of the static conductive plate. One end of the static conductive plate is bent to form two curved portions connecting the two static contacts. The static arc-isolating structure includes a first arc-isolating plate covering the static conductive plate and insulated from the two arc-extinguishing chambers, and a second arc-isolating plate covering the two curved portions. The second arc-isolating plate is connected to the lower side of the front end of the two arc-extinguishing chambers.

[0011] In the above-mentioned high-breakdown DC circuit breaker, the rotating shaft has at least two contact mounting parts, and the two moving contacts are arranged in the mounting cavity of the same contact mounting part through a connecting shaft. Two groups of incoming line assemblies are provided in the shell structure, which are electrically connected to the two groups of moving contact assemblies respectively. Each group of incoming line assemblies includes two flexible connecting lines extending to the rotating shaft and connected to the two moving contacts respectively.

[0012] In the above-mentioned high-breakdown DC circuit breaker, each set of arc extinguishing devices includes a gas-generating insulating cover arranged at the front ends of the two arc extinguishing chambers. The gas-generating insulating cover includes an intermediate cover plate arranged between the two arc extinguishing chambers and two side cover plates arranged on both sides of the intermediate cover plate. The two side cover plates are connected to the second arc isolation plate. The intermediate cover plate and the two side cover plates are opposite to each other to form two arc guide channels connecting the two arc extinguishing chambers. The contact ends of the two moving contacts move respectively in the two arc guide channels.

[0013] In the above-mentioned high-breakdown DC circuit breaker, the two arc extinguishing chambers each include an arc extinguishing cavity and two groups of arc extinguishing sheet assemblies relatively arranged in the arc extinguishing cavity, as well as an inner arc-striking bridge bent and extended to connect the two groups of arc extinguishing sheet assemblies, and a group of upper arc-striking sheets and a group of lower arc-striking sheets arranged at both ends of the two groups of arc extinguishing sheet assemblies, one group of the lower arc-striking sheets is respectively connected to the two static contacts, and one group of the upper arc-striking sheets is bent and extended to the arc guide channel close to the movement trajectory of the moving contact, and an inner insulating plate covering one side of the inner arc-striking bridge is arranged in the arc extinguishing cavity, the two groups of arc extinguishing sheet assemblies are electrically connected through the inner arc-striking bridge, and the two groups of arc extinguishing sheet assemblies are arranged at the front and rear ends of the arc extinguishing chamber.

[0014] In the above-mentioned high-breakdown DC circuit breaker, the two-pole arc extinguishing system also includes two built-in arc extinguishing covers arranged on the second shell and located behind the two arc extinguishing devices. The built-in arc extinguishing covers are connected to the second shell to form an outlet port. The built-in arc extinguishing covers include a built-in baffle extending between the arc extinguishing device and the outlet port, and an arc extinguishing chamber structure opposite to the two arc extinguishing chambers. The arc extinguishing chamber structure is used to deionize and neutralize the free gas discharged from the two arc extinguishing chambers respectively.

[0015] In the above-mentioned high-breakage DC circuit breaker, the arc extinguishing chamber structure includes two arc extinguishing chambers spaced apart in the inner terminal cover and located on the upper side of the outlet port, a grid arc extinguishing plate arranged at the inner end of the arc extinguishing chamber, and two groups of arc extinguishing sheet assemblies arranged in the two arc extinguishing chambers. The outer end of the arc extinguishing chamber is an open structure, and the grid arc extinguishing plate is spaced apart and provided with a plurality of exhaust holes connected to the arc extinguishing chamber and a plurality of grid bar structures formed between the plurality of exhaust holes. The plurality of grid bar structures protrude toward one side of the arc extinguishing chamber and are arranged in an inclined shape, so that an exhaust area with a width gradually increasing from bottom to top is formed between the plurality of grid bar structures and the arc extinguishing chamber.

[0016] In the above-mentioned high-breakage DC circuit breaker, the built-in arc-extinguishing cover includes an intermediate boss arranged between the two arc-extinguishing cavities, an arc-extinguishing bottom plate that separates the two arc-extinguishing cavities from the outlet port up and down, and an operating hole that passes through the intermediate boss and connects to the outlet port. The inner wall of the outlet port is provided with a mounting slot that cooperates with the built-in baffle. The built-in baffle is vertically connected to the bottom of the arc-extinguishing bottom plate. The built-in baffle is extended and connected with the first arc-extinguishing plate covering the static conductive plate.

[0017] In the above-mentioned high-breakage DC circuit breaker, an intermediate partition is provided between the built-in arc-extinguishing cover and the gas-generating insulating cover to separate the two arc-extinguishing chambers. One side of the intermediate partition is integrally connected to the intermediate cover plate of the gas-generating insulating cover, and the other side is inserted into the intermediate boss of the built-in arc-extinguishing cover.

[0018] In the above-mentioned high-breakage DC circuit breaker, the side of the intermediate boss facing the intermediate partition is provided with a first slot that forms a plug-in fit with the intermediate partition, and the first arc-isolating plate covering the static conductive plate is provided with a second slot that forms a plug-in fit with the intermediate partition, and the bottom edge of the intermediate partition is inserted into the second slot.

[0019] The technical solution of the present invention has the following advantages over the prior art:

[0020] 1. In the high-breakage DC circuit breaker provided by the present invention, a double-contact structure and a double-arc extinguishing chamber structure are configured according to each pole circuit. Such a layout design makes the position of one arc extinguishing chamber non-corresponding to that of one moving contact. Therefore, the non-opposite moving contact is extended in a bent structure to cooperate with the arc extinguishing chamber. Such a design has the following advantages: First, the two parallel contacts divide the total current equally into two branches, reducing the current load of a single contact, effectively reducing the current density of the contact surface, suppressing temperature rise, and reducing the risk of thermal runaway, which is particularly suitable for high-current DC scenarios; second, the double breakpoints formed by the double contacts are used to divide a single arc into two independent arcs. Each arc segment is stretched and sucked into the two arc extinguishing chambers under the action of the electric repulsion of the contacts, which significantly improves the arc extinguishing efficiency, thereby distributing the arc energy to the two arc extinguishing chambers, avoiding When a single arc extinguishing chamber is overloaded, it can extinguish the arc faster and more effectively, thereby improving the breaking capacity of the circuit breaker; thirdly, the double contacts rotate synchronously through the shaft to ensure that the two contacts move in unison during disconnection, which can shorten the mechanical disconnection time and avoid the problem of arc reignition caused by asynchronous disconnection. In summary, the core of this dual-contact synchronous action combined with the synergistic effect of the double arc extinguishing chamber is to reduce the loss rate of a single group of contacts / arc extinguishing chambers by sharing the current and arc energy, thereby extending the overall service life of the equipment, and by reasonably optimizing the shell space and the moving contact structure, making the internal transmission, contact, arc extinguishing and other systems of the circuit breaker more stable. Compared with the original structure, it can alleviate problems such as uneven force on the shaft and poor contact of the contacts, enhance the overall mechanical and electrical performance reliability, reduce the occurrence of faults, and improve the long-term stable operation capability of the DC circuit breaker in the power distribution system.

[0021] 2. In the high-breakage DC circuit breaker provided by the present invention, the movable arc isolation structure is composed of a first arc isolation sleeve, a second arc isolation sleeve and a common arc isolation sleeve. This design has the following main advantages: First, the first arc isolation sleeve and the second arc isolation sleeve are respectively sleeved on the two moving contacts and extend between the corresponding arc extinguishing chambers and the guide ports, which can form a physical barrier between the two arc extinguishing chambers and the guide ports, preventing the arc and high-temperature free gas from spreading from the arc extinguishing chamber through the guide ports to the first compartment where the operating mechanism is located, thereby protecting the operating mechanism and other internal components from arc erosion, and improving the safety and reliability of the circuit breaker operation. Reliability; secondly, the first arc-isolating sleeve and the second arc-isolating sleeve have a common isolation sleeve that is overlapped at the guide port. This design forms a tighter isolation structure at the key position of the guide port, further strengthens the arc blocking ability and enhances the arc isolation effect; thirdly, the dynamic arc-isolating structure is coordinated with the layout of the double contacts and double arc extinguishing chambers, and segmented isolation is formed on the path where the dynamic contact passes through the guide port to connect to the arc extinguishing chamber, which not only meets the space required for the movement of the dynamic contact, but also can provide targeted protection for the arc propagation direction of different arc extinguishing chambers, thereby ensuring the stability of the internal structure of the entire circuit breaker and extending the service life of the equipment.

[0022] 3. In the high-breakdown DC circuit breaker provided by the present invention, the second arc-isolating plate is integrally connected to the gas-generating insulating cover, connected to the lower side of the front end of the arc-extinguishing chamber and covered on the curved part of the static conductive plate, thereby forming a continuous isolation screen. This not only blocks the arc from spreading from the arc-extinguishing chamber to the side of the static conductive plate, but also limits the movement of the arc between the arc-extinguishing chambers through the physical barrier of the gas-generating insulating cover, especially when the two arc-extinguishing chambers are arranged in parallel, avoiding insulation failure caused by mutual interference between the two-pole arcs.

[0023] 4. In the high-breakdown DC circuit breaker provided by the present invention, the gas-generating insulating cover adopts an intermediate cover plate + two side cover plates to form two arc guide channel designs, which is well adapted to the parallel layout of the two arc extinguishing chambers in the same pole. The two arc extinguishing chambers are physically separated by the side cover plates and the intermediate cover plates to prevent the high-temperature free gas generated by a single arc extinguishing chamber from diffusing to another arc extinguishing chamber or the static conductive plate area, thereby protecting adjacent components from high-temperature erosion and extending the life of the equipment. The gas-generating insulating cover is installed integrally with the arc extinguishing chamber and the static arc isolation plate as a modular component of the arc extinguishing device, which reduces the assembly steps of independent components and reduces labor costs. At the same time, the gas-generating insulating cover is tightly fitted with the arc extinguishing chamber to enhance the overall sealing of the arc extinguishing system and construct a multi-level insulation protection system. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 It is a schematic diagram of the three-dimensional structure of the high-breakage DC circuit breaker of the present invention;

[0026] Figure 2 Schematic diagram of the cross-sectional structure of the high-breakage DC circuit breaker of the present invention;

[0027] Figure 3 Schematic diagram of the internal structure of the high-breakage DC circuit breaker of the present invention;

[0028] Figure 4 Schematic diagram of the connection structure of the moving contact, the static contact and the arc extinguishing device of the present invention;

[0029] Figure 5 for Figure 4 Schematic diagram of the three-dimensional structure of the moving contact, static contact and arc extinguishing device shown;

[0030] Figure 6 Schematic diagram of the structure of the arc extinguishing device of the present invention;

[0031] Figure 7This is a schematic diagram of the structure of the arc extinguishing device of the present invention with some of its structures hidden;

[0032] Figure 8 This is a schematic structural diagram of the built-in arc extinguishing cover of the present invention;

[0033] Figure 9 It is a structural schematic diagram of the dynamic arc isolation structure of the present invention.

[0034] Explanation of reference numerals: 1. housing structure; 11. first compartment; 12. second compartment; 13. guide port; 14. incoming line assembly; 15. outgoing line port; 16. flexible connecting line; 17. upper cover; 2. arc extinguishing chamber; 21. arc extinguishing plate assembly; 22. inner arc-striking bridge; 23. inner insulating partition; 24. upper arc-striking plate; 25. lower arc-striking plate; 3. rotating shaft; 31. connecting shaft; 32. contact mounting portion; 33. contact compression spring assembly; 4. moving contact; 5. static contact; 51. static conductive plate ; 6. Dynamic arc isolation structure; 61. First arc isolation sleeve; 62. Second isolation sleeve; 7. Static arc isolation structure; 71. First arc isolation plate; 72. Second arc isolation plate; 8. Gas-generating insulation cover; 81. Intermediate cover plate; 82. Side cover plate; 83. Intermediate partition plate; 9. Built-in arc extinguishing cover; 91. Built-in baffle; 92. Arc extinguishing cavity; 93. Grid arc extinguishing plate; 94. Arc extinguishing plate assembly; 95. Bar structure; 96. Intermediate boss; 97. First slot; 98. Operating hole; 100. Operating mechanism. DETAILED DESCRIPTION

[0035] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0036] In the description of the present invention, it should be noted that the terms "first", "second" and "third" are only used for descriptive purposes and should not be understood as indicating or implying relative importance.

[0037] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0038] Example

[0039] The present embodiment will be described in detail below with reference to the accompanying drawings:

[0040] This embodiment provides Figures 1-9 A high-breakage DC circuit breaker shown includes a two-pole electrical contact system, a two-pole arc extinguishing system, and an operating mechanism 100 provided in a housing structure 1; further preferably, the following configuration is provided:

[0041] The housing structure 1 includes two first compartments 11 spaced apart from each other, and two second compartments 12 spaced apart from each other in front and back of the two first compartments 11. A guide port 13 is provided between the first compartments 11 and the second compartments 12. The operating mechanism 100 is centrally disposed in the housing structure 1 and located between the two first compartments 11.

[0042] The two-pole arc extinguishing system includes two arc extinguishing devices arranged in two second compartments 12; each arc extinguishing device includes two arc extinguishing chambers 2 arranged at intervals, one of the arc extinguishing chambers 2 is arranged opposite to the guide port 13, and the other arc extinguishing chamber 2 is arranged staggered with the guide port 13;

[0043] The two-pole electrical contact system includes a rotating shaft 3 arranged in a housing structure and driven by an operating mechanism 100, and two groups of moving contact assemblies connected to the rotating shaft 3 and arranged in two first compartments 11, and two groups of static contact assemblies arranged in two second compartments 12. The rotating shaft 3 drives the two groups of moving contacts 4 to respectively contact or separate with the two groups of contacts under the drive of the operating mechanism 100; wherein, each group of moving contact assemblies includes two moving contacts 4 coaxially arranged on the rotating shaft 3 and connected in parallel in the same pole circuit, and each group of static contact assemblies includes a static conductive plate 51 arranged under the two arc extinguishing chambers and two static contacts 5 formed by the static conductive plate 51 and located in the arc guide channels of the two arc extinguishing chambers. The two moving contacts 4 respectively penetrate into the arc guide channels of the two arc extinguishing chambers 2 and cooperate with the two static contacts 5. One of the moving contacts 4 extends into one of the arc extinguishing chambers 2 in a bent structure after passing through the guide port 13. For specific reference Figure 3 The two moving contacts 4 can be divided into moving contact 1 and moving contact 2, that is, moving contact 1 passes through the guide opening 13 and extends straight into one of the arc extinguishing chambers 2 to cooperate with static contact 1, while moving contact 2 passes through the guide opening 13 and bends to extend into the other arc extinguishing chamber 2 to cooperate with static contact 2.

[0044] In the above embodiment, a double contact structure and a double arc extinguishing chamber structure are configured according to each pole circuit. Such a layout design makes the position of one arc extinguishing chamber 2 and one moving contact 4 non-opposite. Therefore, the moving contact 4 with non-opposite position is extended in a bent structure to cooperate with the arc extinguishing chamber 2. Such a design has the following advantages: First, the two contacts in parallel divide the total current equally into two branches, reducing the current load of a single contact, effectively reducing the current density of the contact surface, suppressing temperature rise, and reducing the risk of thermal runaway, which is especially suitable for high current DC scenarios; second, the double breakpoints formed by the double contacts are used to divide a single arc into two independent arcs. Each arc is stretched and sucked into the two arc extinguishing chambers 2 under the action of the electric repulsion of the contacts, which significantly improves the arc extinguishing efficiency, thereby distributing the arc energy to the two arc extinguishing chambers 2, avoiding a single arc extinguishing. When the arc chamber 2 is overloaded, it can extinguish the arc faster and more effectively, thereby improving the breaking capacity of the circuit breaker; thirdly, the double contacts rotate synchronously through the rotating shaft 3 to ensure that the two contacts move in unison during disconnection, which can shorten the mechanical disconnection time and avoid the problem of arc reignition caused by asynchronous disconnection. In summary, this kind of synchronous action of the double contacts cooperates with the synergistic effect of the double arc extinguishing chamber 2. Its core is to reduce the loss rate of a single group of contacts / arc extinguishing chamber 2 by sharing the current and arc energy, thereby extending the overall service life of the equipment, and through reasonable optimization of the shell space and the moving contact structure, the internal transmission, contact, arc extinguishing and other systems of the circuit breaker are more stably coordinated. Compared with the original structure, it can alleviate problems such as uneven force on the rotating shaft and poor contact of the contacts, enhance the overall mechanical and electrical performance reliability, reduce the occurrence of faults, and improve the long-term stable operation capability of the DC circuit breaker in the power distribution system.

[0045] For further optimization, refer to Figure 2 and Figure 5The rotating shaft 3 includes two contact mounting portions 32 respectively arranged in the two first compartments 11. The two moving contacts 4 are arranged in the mounting cavity of the same contact mounting portion 32 through the connecting shaft 31, and a contact compression spring assembly 33 is provided between the two moving contacts 4 and the mounting cavity. Two groups of incoming line assemblies 14 electrically connected to the two groups of moving contact assemblies are provided in the housing structure. Each group of incoming line assemblies 14 includes two flexible connecting lines 16 extending to the rotating shaft 3 and connected to the two moving contacts 4 respectively. This structural setting integrates the two moving contacts 4 of the same pole into the mounting cavity of the same contact mounting part through a connecting shaft, so that the opening and closing actions of the double contacts are more synchronized and the structure is more compact, avoiding the contact asynchronization problem of "one side high and the other side low" in the traditional structure, reducing the risk of contact burning, and extending the service life. In addition, the incoming current is divided into two paths through two flexible connecting lines 16 and evenly distributed to the two moving contacts 4, so that the current carried by each moving contact is halved, which plays the role of current diversion and thermal stress relief. The heat distribution is more uniform, which is beneficial to reducing the contact temperature rise and preventing structural deformation caused by local overheating. The design of this technical solution utilizes two moving contacts connected in parallel in the same pole circuit to form a double breakpoint structure in the same pole, and makes the current path of each breakpoint independent and balanced. When disconnected, the two breakpoints generate arcs at the same time, and the arc energy is shared by the two arc extinguishing chambers. The double breakpoints cooperate to enhance the arc extinguishing ability. In this design, the energy processed by each arc extinguishing chamber is lower, and the arc is extinguished more quickly and thoroughly, thereby improving the breaking performance of the DC circuit breaker under high voltage.

[0046] In summary, it should be understood that the design of this technical solution is that the two moving contacts 4 are coaxially arranged on the rotating shaft 3, and the gap between the two contacts is small. In addition, the central arrangement of the operating mechanism 100 further occupies the position space of the two moving contacts 4 in the first compartment, and the position space of the two arc extinguishing chambers 2 arranged in the second compartment is significantly larger, which makes the positions of the two arc extinguishing chambers 2 and the two moving contacts 4 of the same pole not completely opposite (that is, one of the moving contacts and the arc extinguishing chamber is staggered). Therefore, it is necessary to make the non-opposite moving contact 4 into a bent structure design to cooperate with the arc extinguishing chamber 2, so that the two moving contacts 4 are precisely matched with the two arc extinguishing chambers 2 to ensure that the arc can be effectively captured and extinguished by the arc extinguishing chamber. Even if the initial position is not completely opposite, the bending design allows the moving contact to extend into the arc extinguishing chamber, which can quickly cut off the arc, improve the breaking capacity, and ensure the reliable operation of the DC distribution system under high voltage. By reasonably optimizing the shell space and the moving contact structure, there is no need to significantly change the overall structure of the shell, adapt to the original installation space, facilitate product miniaturization and integration, and save installation space.

[0047] In this embodiment, in order to prevent the arc from flowing out of the arc extinguishing chamber 2 and spreading along the moving and static contacts to affect other mechanisms or components, Figure 6 and Figure 9As shown, the two moving contacts 4 are provided with a movable arc isolation structure 6 for blocking the arc from spreading from the two arc extinguishing chambers 2 to the side of the guide port 13. The movable arc isolation structure 6 includes a first arc isolation sleeve 61 that is jointly sleeved on the two moving contacts 4 at the guide port 13, and two second arc isolation sleeves 62 that are forked and extended from the first arc isolation sleeve 61 from the guide port 13 to the two arc extinguishing chambers 2. The two second arc isolation sleeves 62 are respectively sleeved on the contact parts of the two moving contacts 4 extending out of the guide port 13. This movable arc-isolating structure 6 is composed of a first arc-isolating sleeve 61 and a second arc-isolating sleeve 62. This design has the following advantages: First, the two second arc-isolating sleeves are respectively sleeved on the two movable contacts 4 and extend between the corresponding arc-extinguishing chambers 2 and the guide openings 13. A physical barrier can be formed between the two arc-extinguishing chambers 2 and the guide openings 13, preventing the arc and high-temperature free gas from spreading from the arc-extinguishing chambers 2 through the guide openings 13 to the first compartment 11 where the operating mechanism 100 is located, thereby protecting the operating mechanism 100 and other internal components from arc erosion and improving the safety and reliability of the circuit breaker operation. Secondly, a tighter isolation structure is formed at the key position of the guide port 13 by jointly sleeved on the two moving contacts 4 with the first arc isolation sleeve 61, thereby further strengthening the arc blocking capability and arc isolation effect; thirdly, by coordinating the movable arc isolation structure 6 with the layout of the double contacts and the double arc extinguishing chambers, segmented isolation is formed on the path where the moving contact 4 passes through the guide port 13 to connect to the arc extinguishing chamber 2, which not only meets the space required for the movement of the moving contact, but also can provide targeted protection for the arc propagation direction of different arc extinguishing chambers 2, thereby ensuring the stability of the internal structure of the entire circuit breaker and extending the service life of the equipment.

[0048] Furthermore, each set of static contact assemblies is preferably provided with a static arc-isolating structure 7 for preventing arcs from propagating from the two arc-extinguishing chambers 2 toward the static conductive plate 51. One end of the static conductive plate 51 is bent to form two curved portions connecting the two static contacts 5. The static arc-isolating structure 7 includes a first arc-isolating plate 71 covering the static conductive plate 51 and insulated and separated from the two arc-extinguishing chambers 2, and a second arc-isolating plate 72 covering the two curved portions. The second arc-isolating plate 72 is connected to the lower front ends of the two arc-extinguishing chambers 2. This structural arrangement, in which the second arc-isolating plate 72 is integrally connected to the gas-generating insulating cover 8, connects to the lower front ends of the arc-extinguishing chambers 2 and covers the curved portions of the static conductive plate 51, thereby forming a continuous isolation screen. This not only prevents arc propagation from the arc-extinguishing chambers 2 toward the static conductive plate 51, but also limits arc movement between the arc-extinguishing chambers 2 through the physical barrier of the gas-generating insulating cover 8. This, in particular, prevents insulation failure caused by mutual interference between the two polarity arcs when two arc-extinguishing chambers are arranged in parallel.

[0049] The following combination Figure 2-Figure 8 The specific setting method of the arc extinguishing device is described in detail:

[0050] Each set of arc extinguishing devices includes a gas-generating insulating cover 8 arranged at the front ends of the two arc extinguishing chambers 2. The gas-generating insulating cover 8 includes an intermediate cover plate 81 arranged between the two arc extinguishing chambers 2 and two side cover plates 82 arranged on both sides of the intermediate cover plate 81. The two side cover plates 82 are connected to the second arc isolation plate 72. The intermediate cover plate 81 and the two side cover plates 82 are relatively formed with two arc guide channels connecting the two arc extinguishing chambers 2. The contact ends of the two moving contacts 4 move in the two arc guide channels respectively. This structural setting, the gas-generating insulating cover 8 adopts the middle cover plate 81 and the two side cover plates 82 to form two arc guide channel designs, which is well adapted to the parallel layout of the two arc extinguishing chambers 2 in the same pole. The two arc extinguishing chambers 2 are physically separated by the side cover plates 82 and the middle cover plates 81 to prevent the high-temperature free gas generated by a single arc extinguishing chamber from diffusing to another arc extinguishing chamber or the static conductive plate area, thereby protecting adjacent components from high-temperature erosion and extending the life of the equipment. The gas-generating insulating cover 8 is installed integrally with the arc extinguishing chamber 2 and the static arc isolation plate as a modular component of the arc extinguishing device, which reduces the assembly steps of independent components and reduces labor costs. At the same time, the gas-generating insulating cover 8 is tightly fitted with the arc extinguishing chamber 2 to enhance the overall sealing of the arc extinguishing system and construct a multi-level insulation protection system.

[0051] like Figure 2As shown, the two arc extinguishing chambers 2 each include an arc extinguishing chamber and two groups of arc extinguishing sheet assemblies 21 relatively arranged in the arc extinguishing chamber, as well as an inner arc striking bridge 22 bent and extended to connect between the two groups of arc extinguishing sheet assemblies 21, and a group of upper arc striking sheets 24 and a group of lower arc striking sheets 25 arranged at both ends of the two groups of arc extinguishing sheet assemblies, one group of the lower arc striking sheets 25 are respectively connected to the two static contacts 5, and one group of the upper arc striking sheets 24 are bent and extended to the arc guide channel close to the motion trajectory of the moving contact 4, and the contact end of the moving contact is correspondingly provided with an arc striking angle matched with the upper arc striking sheet, thereby shortening the jumping distance of the arc from the moving contact 4 to the upper end of the arc extinguishing chamber, which is beneficial to guiding the electric arc on the moving contact The arc is quickly transferred to the upper arc-striking plate and introduced into the arc-extinguishing chamber to achieve the effects of rapid arc ignition and arc extinguishing, and the arc on the static contact is quickly introduced into the arc-extinguishing chamber through the lower arc-striking plate, and an inner insulating partition 23 covering one side of the inner arc-striking bridge 22 is provided in the arc-extinguishing chamber. The two groups of arc-extinguishing plate assemblies 21 are electrically connected through the inner arc-striking bridge 22. The two groups of arc-extinguishing plate assemblies 21 are arranged at the front and rear ends of the arc-extinguishing chamber 2. The inner insulating partition 23 can prevent the arc from spreading to unexpected areas inside the arc-extinguishing chamber, and can form an insulating barrier between the two groups of arc-extinguishing plate assemblies 21 to prevent arc penetration or creepage, thereby ensuring the electrical insulation performance of the internal structure of the arc-extinguishing chamber. In this embodiment, two groups of arc extinguishing plate assemblies 21 are configured in the two arc extinguishing chambers 2 of each pole, and the design of realizing electrical connection through the internal arc-starting bridge 22 has the following advantages: two groups of arc extinguishing plate assemblies 21 are arranged in each arc extinguishing chamber 2, which can form a larger arc dividing space compared with the single group of arc extinguishing plates in the existing arc extinguishing chamber, and greatly increase the number of arc extinguishing plates set, thereby effectively increasing the overall capacity of the arc extinguishing chamber; when the double contacts are disconnected, the arc is guided to between the two groups of arc extinguishing plates by using the arc guide channel, arc-starting plates and internal arc starting to realize arc extinguishing, which significantly improves the arc extinguishing speed; this internal arc-starting bridge 22 has the function of guiding the arc path, which can accurately guide the arc from the contact gap quickly into the two groups of arc extinguishing plate areas, reduce the risk of contact burning, and at the same time evenly distribute the arc energy to the two groups of arc extinguishing plates, avoid overheating of a single area, and realize the arc extinguishing effect of partitioning and pressure separation through the two groups of arc extinguishing plate assemblies 21. In summary, this technical solution adopts a parallel structure of dual arc extinguishing chambers and dual contacts, and combines the structural design of the dual arc extinguishing components of the arc extinguishing chamber to achieve a double sharing effect on current and arc energy, thereby greatly reducing the arc energy borne by a single set of arc extinguishing sheets, effectively avoiding overload of a single arc extinguishing chamber, and improving the circuit breaker's disconnection reliability in high current and high voltage scenarios.

[0052] The DC circuit breaker provided in this embodiment has a large breaking current, so a small amount of charged ionized gas or residual arc will be ejected from the rear of the arc extinguishing chamber 2. Figure 2 、 Figure 6-Figure 8As shown, in order to achieve the purpose of zero arcing, the two-pole arc extinguishing system also includes two built-in arc extinguishing covers 9 arranged on the second shell part and located behind the two arc extinguishing devices, and an upper cover 17 is installed on the shell structure 1, and the built-in arc extinguishing cover 9 is limitedly installed between the upper cover 17 and the shell structure 1, wherein the built-in arc extinguishing cover 9 is connected to the second shell part to form an outlet port 15, and an outlet assembly is provided in the outlet port 15, and the built-in arc extinguishing cover 9 includes a built-in baffle 91 extending between the arc extinguishing chamber 2 and the outlet port 15, and an arc extinguishing chamber structure opposite to the two arc extinguishing chambers 2, extending to the outlet port 15 according to the static conductive plate 51, the built-in baffle 91 cooperates and abuts against the static conductive plate 51, and the first arc extinguishing plate covering the static conductive plate 51 extends and is connected to the built-in baffle 91, thereby improving the insulation isolation protection of the static conductive plate 51, and the arc extinguishing chamber structure is used to deionize and neutralize the free gas discharged from the two arc extinguishing chambers 2 respectively. This structural setting forcibly separates the arc extinguishing area and the output terminal area through the built-in baffle 91, forcing the arc to move along a preset path toward the arc extinguishing chamber structure, avoiding the high-temperature arc and metal particles ejected during arc extinguishing from directly impacting the output terminal. Through the physical isolation of the built-in baffle 91 and the secondary arc extinguishing of the arc extinguishing chamber structure, the output terminal and external circuit are protected in all directions from the two levels of spatial isolation and energy elimination, reducing the risks of arc reignition, short circuit, etc., and adapting to the high voltage and high current scenarios of DC circuit breakers.

[0053] The following combination Figure 6-Figure 8 The specific structure of the built-in arc extinguishing cover 9 is described in detail:

[0054] The arc extinguishing chamber structure includes two arc extinguishing chambers 92 that are spaced apart and located on the upper side of the outlet port 15, a grid arc extinguishing plate 93 that is arranged at the inner end of the arc extinguishing chamber 92, and two groups of arc extinguishing sheet assemblies 94 that are arranged in the two arc extinguishing chambers 92. The outer end of the arc extinguishing chamber 92 is an open structure. The grid arc extinguishing plate 93 is spaced apart and provided with a plurality of exhaust holes that communicate with the arc extinguishing chamber 92 and a plurality of grid bar structures 95 formed between the plurality of exhaust holes. The plurality of grid bar structures 95 protrude toward one side of the arc extinguishing chamber 2 and are arranged in an inclined shape, so that a wide gap is formed between the plurality of grid bar structures 95 and the arc extinguishing chamber 2. The exhaust area gradually increases in degree from bottom to top, and it is further provided that the built-in arc-extinguishing cover 9 includes an intermediate boss 96 arranged between the two arc-extinguishing cavities 92, and an arc-extinguishing bottom plate separating the two arc-extinguishing cavities 92 from the outlet port 15 up and down, and an operating hole 98 that passes through the intermediate boss 96 and connects to the outlet port 15. The inner wall of the outlet port 15 is provided with a mounting groove that cooperates with the built-in baffle 91. The positioning and installation of the built-in baffle 91 are achieved through the mounting groove. The operator can use a tool to penetrate the operating hole 98 to perform wiring operations on the terminal blocks in the outlet port 15. From the structure of the above-mentioned built-in arc extinguishing hood 9, it can be seen that multiple bar structures 95 are arranged obliquely on the side of the grid arc extinguishing plate 93 facing the arc extinguishing chamber 2, and form an exhaust area that is narrow at the bottom and wide at the top between the arc extinguishing chamber 2. This structural setting utilizes the tendency of the arc to move upward, and divides the arc into multiple short arcs through the obliquely arranged bar structures 95, thereby reducing the arc energy, and the bar structure 95 forms a sieve effect on the molten metal particles, so that large metal particles are directly intercepted, and then a secondary arc extinguishing barrier is formed by two groups of arc extinguishing plate assemblies 94 arranged in the arc extinguishing cavity 92, thereby playing the role of secondary arc extinguishing, arc extinguishing and neutralizing free gas. This arc extinguishing chamber structure adopts the combined effect of bar structure and arc extinguishing plate to greatly reduce the residual arc energy and charged particle concentration at the output end of the circuit breaker, and improve the insulation performance between terminals and terminals to ground. According to the use of built-in arc extinguishing hood in the DC circuit breaker, the breaking capacity, insulation life and operation safety of the circuit breaker can be significantly improved in the DC system.

[0055] It is further preferred that an intermediate partition 83 is provided between the built-in arc-extinguishing hood 9 and the gas-producing insulating hood 8 to separate the two arc-extinguishing chambers 2, one side of the intermediate partition 83 is integrally connected with the intermediate cover plate 81 of the gas-producing insulating hood 8, and the other side is plugged into the intermediate boss 96 of the built-in arc-extinguishing hood 9, wherein the side of the intermediate boss 96 facing the intermediate partition is provided with a first slot 97 that forms a plug-in fit with the intermediate partition, and the first arc-extinguishing plate 71 is provided with a second slot that forms a plug-in fit with the intermediate partition 83, and the bottom edge of the intermediate partition 71 is inserted into the second slot. This middle partition 83 is precisely matched with the middle boss 96 through the first slot, and the bottom edge of the middle partition 83 is precisely matched with the first arc-isolating plate 71 through the second slot. This design effectively keeps the relative position between the gas-generating insulating cover 8 and the built-in arc-extinguishing cover 9 fixed, avoiding the displacement of components caused by factors such as electric repulsion and vibration during the disconnection process. In addition, the two arc-extinguishing chambers 2 in the same pole are directly separated by the middle partition 83, preventing the high-temperature free gas and arc plasma generated by a single arc-extinguishing chamber from spreading to the adjacent arc-extinguishing chamber. Especially when the two arc-extinguishing chambers are arranged in parallel, the risk of phase-to-phase short circuit caused by arc movement can be effectively prevented, thereby improving the insulation stability of the circuit breaker under high voltage conditions.

[0056] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A high-breakage DC circuit breaker, comprising a two-pole electrical contact system, a two-pole arc extinguishing system and an operating mechanism (100) arranged in a housing structure (1); characterized in that: The housing structure (1) comprises two first compartments (11) and two second compartments (12) that are spaced apart from each other, a guide port (13) being provided between the first compartments (11) and the second compartments (12), and the operating mechanism (100) being centrally arranged in the housing structure (1) and located between the two first compartments (11); The two-pole arc extinguishing system comprises two arc extinguishing devices arranged in two second compartments (12); each arc extinguishing device comprises two arc extinguishing chambers (2) arranged at intervals, one of the arc extinguishing chambers (2) being arranged opposite to the guide opening (13), and the other arc extinguishing chamber (2) being arranged staggered with the guide opening (13); The two-pole electric contact system comprises a rotating shaft (3) driven by an operating mechanism and arranged in a housing structure, two groups of movable contact components connected to the rotating shaft and arranged in two first compartments (11), and two groups of stationary contact components arranged in two second compartments (12); each group of movable contact components comprises two movable contacts (4) coaxially arranged on the rotating shaft (3) and connected in parallel in the same polarity circuit, and each group of stationary contact components comprises a stationary conductive plate (51) arranged under two arc extinguishing chambers and two stationary contacts (5) formed by the stationary conductive plate (51) and located in arc guide channels of the two arc extinguishing chambers, the two movable contacts (4) respectively penetrate into the arc guide channels of the two arc extinguishing chambers and cooperate with the two stationary contacts (5), and one of the movable contacts (4) extends into one of the arc extinguishing chambers (2) in a bent structure after passing through the guide opening.

2. The high-breakage DC circuit breaker according to claim 1, characterized in that: A movable arc isolation structure (6) for blocking the arc from spreading from the two arc extinguishing chambers (2) to one side of the guide port (13) is sleeved on the two moving contacts (4). The movable arc isolation structure (6) comprises a first arc isolation sleeve (61) sleeved on the two moving contacts (4) at the guide port (13), and two second arc isolation sleeves (62) bifurcated from the first arc isolation sleeve (61) and extending from the guide port (13) to the two arc extinguishing chambers (2). The two second arc isolation sleeves (62) are respectively sleeved on the contact portions of the two moving contacts (4) extending out of the guide port (13).

3. The high-breakage DC circuit breaker according to claim 2, characterized in that: Each group of static contact assemblies is provided with a static arc isolation structure (7) for blocking the arc from spreading from the two arc extinguishing chambers (2) to one side of the static conductive plate (51); one end of the static conductive plate (51) is bent to form two curved portions connecting the two static contacts (5); the static arc isolation structure (7) comprises a first arc isolation plate (71) covering the static conductive plate (51) and insulated and separated from the two arc extinguishing chambers (2); and a second arc isolation plate (72) covering the two curved portions; the second arc isolation plate (72) is connected to the lower side of the front ends of the two arc extinguishing chambers (2).

4. The high-breakage DC circuit breaker according to claim 1, characterized in that: The rotating shaft (3) includes two contact mounting portions respectively arranged in two first compartments (11); two moving contacts (4) are arranged in the mounting cavity of the same contact mounting portion (32) via a connecting shaft (31); two groups of incoming line assemblies (14) electrically connected to the two groups of moving contact assemblies are provided in the housing structure; each group of incoming line assemblies (14) includes two flexible connecting lines (16) extending to the rotating shaft (3) and connected to the two moving contacts (4) respectively.

5. The high-breakage DC circuit breaker according to claim 1, characterized in that: Each set of arc extinguishing devices comprises a gas-generating insulating cover (8) arranged at the front ends of two arc extinguishing chambers (2), the gas-generating insulating cover (8) comprising an intermediate cover plate (81) arranged between the two arc extinguishing chambers (2) and two side cover plates (82) respectively arranged on both sides of the intermediate cover plate (81), the two side cover plates (82) being connected to a second arc isolation plate (72), the intermediate cover plate (81) and the two side cover plates (82) being opposite to each other to form two arc guide channels connecting the two arc extinguishing chambers (2), and the contact ends of the two moving contacts (4) respectively move in the two arc guide channels.

6. The high-breakage DC circuit breaker according to claim 5, characterized in that: The two arc extinguishing chambers (2) each include an arc extinguishing chamber and two groups of arc extinguishing sheet assemblies (21) arranged relatively in the arc extinguishing chamber, an inner arc striking bridge (22) bent and extended to connect between the two groups of arc extinguishing sheet assemblies (21), and a group of upper arc striking sheets and a group of lower arc striking sheets arranged at both ends of the two groups of arc extinguishing sheet assemblies, one group of the lower arc striking sheets (25) being connected to the two static contacts (5) respectively, and one group of the upper arc striking sheets (24) being bent and extended to the arc guide channel close to the motion trajectory of the moving contact (4), and an inner insulating plate covering one side of the inner arc striking bridge (22) being arranged in the arc extinguishing chamber, the two groups of arc extinguishing sheet assemblies (21) being electrically connected via the inner arc striking bridge (22), and the two groups of arc extinguishing sheet assemblies (21) being arranged at the front and rear ends of the arc extinguishing chamber (2).

7. The high-breakage DC circuit breaker according to any one of claims 1 to 6, characterized in that: The bipolar arc extinguishing system further comprises two built-in arc extinguishing covers (9) arranged at one end of the housing structure (1) and located behind the two arc extinguishing devices. The built-in arc extinguishing covers (9) are connected to the housing structure (1) to form an outlet port (15). The built-in arc extinguishing covers (9) comprise a built-in baffle (91) extending between the arc extinguishing chamber (2) and the outlet port (15), and an arc extinguishing chamber structure arranged above the built-in baffle and opposite to the two arc extinguishing chambers (2). The arc extinguishing chamber structure is used to perform deionization and neutralization treatment on the free gas discharged from the two arc extinguishing chambers (2).

8. The high-breakage DC circuit breaker according to claim 7, characterized in that: The arc extinguishing chamber structure comprises two arc extinguishing chambers (92) arranged at intervals in the built-in arc extinguishing cover (9) and located on the upper side of the outlet port (15), two groups of arc extinguishing sheet assemblies (94) arranged in the two arc extinguishing chambers (92), and a grid arc extinguishing plate (93) arranged at the inner end of the arc extinguishing chamber (92), the outer end of the arc extinguishing chamber (92) is an open structure, the grid arc extinguishing plate (93) is provided with a plurality of exhaust holes and a plurality of grid bar structures (95) formed between the plurality of exhaust holes, the plurality of grid bar structures (95) protruding toward one side of the arc extinguishing chamber (2) and arranged in an inclined shape, so that an exhaust area with a width gradually increasing from bottom to top is formed between the plurality of grid bar structures (95) and the arc extinguishing chamber (2).

9. The high-breakage DC circuit breaker according to claim 8, characterized in that: The built-in arc-extinguishing cover (9) includes a middle boss (96) arranged between two arc-extinguishing cavities (92), and an operating hole (98) penetrating the middle boss (96) and communicating with the outlet port (15). An arc-isolating bottom plate separated from each other is provided between the two arc-extinguishing cavities (92) and the outlet port (15). The built-in baffle (91) is vertically connected to the bottom of the arc-isolating bottom plate. The built-in baffle (91) is cooperatively connected to a first arc-isolating plate (71) covering the static conductive plate (51).

10. The high-breakage DC circuit breaker according to claim 7, characterized in that: An intermediate partition (83) is provided between the built-in arc extinguishing hood (9) and the gas-generating insulating hood (8), separating the two arc extinguishing chambers (2). One side edge of the intermediate partition (83) is integrally connected to the intermediate cover plate (81) of the gas-generating insulating hood (8), and the other side edge is plugged into the intermediate boss (96) of the built-in arc extinguishing hood (9).

11. The high-breakage DC circuit breaker according to claim 10, characterized in that: The side of the middle boss (96) facing the middle partition (83) is provided with a first slot (97) that forms a plug-fitting connection with the middle partition; the first arc isolation plate (71) covering the static conductive plate is provided with a second slot that forms a plug-fitting connection with the middle partition (83); the bottom edge of the middle partition (83) is inserted into the second slot.

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