A magnetic blowout arc extinguishing device

Abstract

The application discloses a magnetic arc extinguishing device, which comprises two magnetic steels for generating a magnetic field and arc extinguishing grid plates made of low-carbon steel. The two magnetic steels are arranged in front of and behind each other, and the arc extinguishing grid plates are located between the two magnetic steels. Each magnetic steel is a bipolar magnetized steel. The two magnetic steels are respectively referred to as a first magnetic steel and a second magnetic steel in front-to-back order. A first low-carbon steel plate is attached to the front side of the first magnetic steel, and a second low-carbon steel plate is attached to the back side of the second magnetic steel. The two magnetic steels, the first low-carbon steel plate and the second low-carbon steel plate form a closed magnetic circuit structure. The first low-carbon steel plate and the second low-carbon steel plate are both used for gathering the magnetic field to reduce magnetic leakage. The magnetic arc extinguishing device can generate a strong magnetic field, provide a large Lorentz force, realize fast stretching of an electric arc and extinguish the electric arc.

Description

Technical Field

[0001] This invention relates to arc extinguishing devices, and more particularly to a magnetic blowout arc extinguishing device. Background Technology

[0002] During the use of DC switches, the breaking of the circuit will generate a high-temperature arc. If this high-temperature arc cannot be extinguished quickly, it will have a significant impact on the contacts of the DC switch and may even pose a safety risk. Therefore, DC switches are generally equipped with arc-extinguishing devices to achieve rapid arc extinguishing.

[0003] Currently, magnetic blowout arc extinguishing devices are widely used in medium and low voltage DC switches. For example, the arc extinguishing device disclosed in Chinese patent application CN117936297A uses a magnet to provide a magnetic field, achieving the purpose of stretching and extinguishing the arc within the magnetic field. However, the arc generation location of this device is on the side of the magnet's thickness, i.e., the side facing the orientation direction. The magnetic field at this location is leakage magnetic field on the side of the magnet, and the magnetic field direction is parallel to the magnet's thickness direction. In the initial stage of arc generation, the force direction is perpendicular to the magnet's thickness direction. This force situation is unfavorable for the arc to quickly enter the arc extinguishing space, affecting the arc extinguishing speed. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a magnetic arc extinguishing device that can generate a strong magnetic field, provide a large Lorentz force, and realize the rapid stretching and extinguishing of the electric arc.

[0005] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: a magnetic blowout arc extinguishing device, comprising two magnets for generating a magnetic field and an arc extinguishing grid plate made of low-carbon steel. The two magnets are arranged at intervals, and the arc extinguishing grid plate is located between the two magnets. Each magnet is a bipolar magnetized steel. The two magnets are referred to as the first magnet and the second magnet in front-to-back order. A first low-carbon steel plate is attached to the front side of the first magnet, and a second low-carbon steel plate is attached to the rear side of the second magnet. The two magnets, the first low-carbon steel plate, and the second low-carbon steel plate form a closed magnetic circuit structure. Both the first low-carbon steel plate and the second low-carbon steel plate are used to concentrate the magnetic field to reduce magnetic leakage.

[0006] Compared with the prior art, the advantage of the present invention lies in the fact that it uses two bipolar magnetized steels and a low-carbon steel plate attached thereto to form a closed magnetic circuit structure, that is, the left N pole of the first magnet and the left S pole of the second magnet are opposite each other, and the right S pole of the first magnet and the right N pole of the second magnet are opposite each other. In this magnetic circuit structure, the magnetic field lines run along the path of the first magnet's left N pole → the second magnet's left S pole → the second magnet's left N pole → the second low-carbon steel plate → the second magnet's right S pole → the second magnet's right N pole → the first magnet's right S pole → the first magnet's right N pole → the first low-carbon steel plate → the first magnet's left S pole → the first magnet's left N pole. Thus, the magnetic fields generated by the two bipolar magnetized steels form a loop, which can effectively superimpose rather than cancel each other, thereby significantly enhancing the magnetic field strength. The first and second low-carbon steel plates further concentrate the magnetic field and reduce magnetic leakage, thereby ensuring that a strong magnetic field space is formed between the two bipolar magnetized steels. The arc-extinguishing grid plate, made of low-carbon steel, is located in this strong magnetic field space. When the DC switch is turned off, the arc formed is subjected to a large Lorentz force, which will be rapidly stretched and quickly enter the arc-extinguishing grid plate to extinguish the arc. Thus, the present invention can generate a strong magnetic field and provide a large Lorentz force to achieve rapid stretching and extinguishing of the arc.

[0007] Furthermore, the overall structure formed by the first magnet and the first low-carbon steel plate is surrounded by a first insulating frame on the front, back, left, and right sides; the overall structure formed by the second magnet and the second low-carbon steel plate is surrounded by a second insulating frame on the front, back, left, and right sides; the left ends of the first insulating frame and the second insulating frame are connected by an insulating component, and the first insulating frame, the second insulating frame, and the insulating component form a U-shaped structure with an opening on the right side, and the arc-extinguishing grid plate is located inside the U-shaped structure and is respectively attached to the first insulating frame, the second insulating frame, and the insulating component.

[0008] Furthermore, the two magnets, the first low-carbon steel plate, and the second low-carbon steel plate are all cuboid structures, and their upper, lower, left, and right sides are aligned. The first and second insulating frames are both square frames, the insulating component is a cuboid structure, and the arc-extinguishing grid is formed by multiple cuboid sheets of identical size, evenly spaced and aligned vertically. The upper side of the arc-extinguishing grid is lower than the upper sides of the two magnets, the first low-carbon steel plate, and the second low-carbon steel plate, and the lower side is higher than the lower sides of the two magnets, the first low-carbon steel plate, and the second low-carbon steel plate. The arc-extinguishing grid is located in the left half of the space formed between the two magnets. Attached Figure Description

[0009] Figure 1 This is a top view schematic diagram of the magnetic blowout arc extinguishing device of the present invention;

[0010] Figure 2 for Figure 1 The image shows a left view of the magnetic blowout arc extinguishing device of the present invention;

[0011] Figure 3 for Figure 1 The image shown is a rear view of the magnetic blowout arc extinguishing device of the present invention.

[0012] Figure 4 This is a diagram showing the magnetic field lines of the magnetic field generated by the magnetic blowout arc extinguishing device of the present invention.

[0013] Figure 5 This is a schematic diagram of the arc-extinguishing grid plate of the magnetic blowout arc-extinguishing device of the present invention;

[0014] Figure 6 This is a simulated magnetic field distribution cloud map of the magnetic blowout arc extinguishing device of the present invention;

[0015] Figure 7 The diagram shows the simulated magnetic field magnitude from top to bottom at the center of the arc-extinguishing space of the magnetic blowout arc-extinguishing device of the present invention. Detailed Implementation

[0016] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0017] Example 1: As Figures 1 to 3 As shown, a magnetic blowout arc extinguishing device includes two magnets for generating a magnetic field. The two magnets are arranged at a distance from each other, and each magnet is a bipolar magnetized steel. The two magnets are referred to as the first magnet 1 and the second magnet 2 in front-to-back order. A first low-carbon steel plate 3 is attached to the front side of the first magnet 1, and a second low-carbon steel plate 4 is attached to the rear side of the second magnet 2. An arc extinguishing grid plate 5 made of low-carbon steel is arranged between the two magnets. The first magnet 1, the first low-carbon steel plate 3, the second magnet 2, and the second low-carbon steel plate 4 form a closed magnetic circuit structure, that is, the left N pole of the first magnet 1 and the left S pole of the second magnet 2 are opposite each other, and the right S pole of the first magnet 1 and the right N pole of the second magnet 2 are opposite each other. The first low-carbon steel plate 3 and the second low-carbon steel plate 4 are both used to concentrate the magnetic field to reduce magnetic leakage.

[0018] In this embodiment, a bipolar magnetized steel design is adopted, and a low-carbon steel plate is adsorbed on the back to concentrate the magnetic field to reduce magnetic leakage, and the entire magnetic field forms a loop.

[0019] like Figure 4As shown, the magnetic field lines follow the path from the left N pole of the first magnet 1 to the left S pole of the second magnet 2, then to the second low-carbon steel plate 4, the right S pole of the second magnet 2, the right N pole of the second magnet 2, the right S pole of the first magnet 1, the right N pole of the first magnet 1, the first low-carbon steel plate 3, the left S pole of the first magnet 1, and finally the left N pole of the first magnet 1. Thus, the magnetic fields generated by the first magnet 1 and the second magnet 2 effectively superimpose rather than cancel each other out, significantly enhancing the magnetic field strength and providing a strong magnetic field space for the arc-extinguishing device. Since the arc-extinguishing speed depends on the magnitude of the arc force, this strong magnetic field space can provide a large Lorentz force, thereby significantly increasing the arc force and thus increasing the arc-extinguishing speed, enabling rapid arc stretching and extinguishing.

[0020] Example 2: This example is basically the same as Example 1, except that: in this example, the overall structure formed by the first magnet 1 and the first low-carbon steel plate 3 is surrounded by the first insulating frame 6 on the front, back, left and right sides; the overall structure formed by the second magnet 2 and the second low-carbon steel plate 4 is surrounded by the second insulating frame 7 on the front, back, left and right sides; the left ends of the first insulating frame 6 and the second insulating frame 7 are connected by the insulating member 8, and the first insulating frame 6, the second insulating frame 7 and the insulating member 8 form a U-shaped structure with an opening on the right side. The arc-extinguishing grid plate 5 is located inside the U-shaped structure and is attached to the first insulating frame 6, the second insulating frame 7 and the insulating member 8 respectively.

[0021] In this embodiment, the first magnet 1, the first low-carbon steel plate 3, the second magnet 2, and the second low-carbon steel plate 4 are all cuboid structures, and their upper, lower, left, and right sides are aligned. The first insulating frame 6 and the second insulating frame 7 are both square frames, and the insulating component 8 is a cuboid structure.

[0022] like Figure 5 As shown, the arc-extinguishing grid 5 is formed by 10 rectangular sheets 51 of the same size, which are aligned vertically and evenly spaced. The upper side of the arc-extinguishing grid 5 is lower than the upper side of the first magnet 1, and the lower side is higher than the lower side of the first magnet 1. The arc-extinguishing grid 5 is located in the left half of the space formed between the two magnets, so as to ensure that when the two magnets generate a magnetic field, the magnetic field lines pass through the arc-extinguishing grid 5 from the left N pole of the first magnet 1 to the left S pole of the second magnet 2, but do not pass through the arc-extinguishing grid 5 from the right N pole of the second magnet 2 to the right S pole of the first magnet 1. Thus, an arc-extinguishing space is formed between the right N pole of the second magnet 2 and the right S pole of the first magnet 1.

[0023] In this embodiment, the first insulating frame 6, the second insulating frame 7, and the insulating component 8 are all made of plastic.

[0024] In this embodiment, the overall structure formed by the first insulating frame 6, the second insulating frame 7, and the insulating component 8 provides frame support for the first magnet 1, the first low-carbon steel plate 3, the second magnet 2, the second low-carbon steel plate 4, and the arc-extinguishing grid plate 5. On the other hand, it serves as insulation to prevent the electric arc from being attracted to the first magnet 1 and the second magnet 2, thus preventing damage to the first magnet 1 and the second magnet 2.

[0025] To verify the performance of the magnetic blowout arc extinguishing device of the present invention, the device was simulated using ANSoft software, and the results were obtained. Figure 6 The simulated magnetic field distribution cloud map shown and Figure 7 The simulation results show the magnetic field magnitude from top to bottom at the center of the arc-extinguishing space of the simulated magnetic field. During the simulation, both the first magnet 1 and the second magnet 2 were 48H grade magnets with dimensions (length × width × thickness) of 30mm × 30mm × 3mm, magnetized using bipolar magnetization, and the gap between the first magnet 1 and the second magnet 2 was set to 7mm. The dimensions (length × width × thickness) of the first low-carbon steel plate 3 and the second low-carbon steel plate 4 were both 30mm × 30mm × 2mm. The arc-extinguishing grid plate 5 was composed of 10 rectangular sheets 51 with dimensions (length × width × thickness) of 15mm × 5mm × 1mm stacked at 2mm intervals, and the rectangular sheets 51 were made of low-carbon steel plate. Since other components do not affect the magnetic circuit, only the spatial distance was retained in the simulation, and other factors were not considered. The first magnet 1, the second magnet 2, the first low-carbon steel plate 3, the second low-carbon steel plate 4, and the arc-extinguishing grid plate 5 were arranged in the relative positions of Embodiment 1.

[0026] Figure 6 In this context, B represents magnetic flux density, and tesla is the unit of magnetic flux density, Tesla. Analysis Figure 6 It can be seen that since both the first magnet 1 and the second magnet 2 are bipolar magnetized steels, their inner magnetic fields form a loop. The addition of the first low-carbon steel plate 3 and the second low-carbon steel plate 4 effectively converges the leakage magnetic fields on the outer sides of the first magnet 1 and the second magnet 2, further enhancing the strength of the inner magnetic field.

[0027] Figure 7 In this context, B represents magnetic flux density, and mTesla is the unit of magnetic flux density: millitalas. Analysis Figure 7 It can be seen that the magnetic field strength at the center of the arc-extinguishing space of the magnetic blowout arc-extinguishing device of the present invention can reach over 300 mT. This proves that the magnetic blowout arc-extinguishing device of the present invention can provide a strong magnetic field space for the arc. Theoretically, if the gap between the first magnet 1 and the second magnet 2 is further reduced, an even stronger magnetic field can be provided for the arc-extinguishing space. Therefore, in practical applications, under permissible conditions, the gap between the first magnet 1 and the second magnet 2 can be reduced as much as possible to achieve a stronger magnetic field.

[0028] In summary, the magnetic blowout arc extinguishing device of the present invention forms a closed magnetic circuit structure by using a first magnet 1, a first low-carbon steel plate 3, a second magnet 2, and a second low-carbon steel plate 4. Both the first magnet 1 and the second magnet 2 are bipolar magnetized steels. The magnetic fields generated by the first magnet 1 and the second magnet 2 form a loop, which can effectively superimpose rather than cancel each other, thereby significantly enhancing the magnetic field strength. The first low-carbon steel plate 3 and the second low-carbon steel plate 4 further concentrate the magnetic field and reduce magnetic leakage, thereby ensuring that a uniform strong magnetic field space is formed between the first magnet 1 and the second magnet 2. The arc extinguishing grid plate 5 is located in this strong magnetic field space. When the DC switch is turned off, the arc formed is subjected to a large Lorentz force, which will be rapidly stretched and quickly enter the arc extinguishing grid plate 5, realizing the rapid stretching and extinguishing of the arc.

Claims

1. A magnetic arc extinguishing device, comprising two pieces of magnetic steel for generating a magnetic field and arc extinguishing grid vanes made of low carbon steel, the two pieces of magnetic steel being arranged in front of and behind each other, the arc extinguishing grid vanes being located between the two pieces of magnetic steel, characterized in that: Each magnetic steel is a bipolar magnetized steel, two magnetic steels are called first magnetic steel and second magnetic steel in sequence, a first low carbon steel plate is attached to the front side of the first magnetic steel, a second low carbon steel plate is attached to the back side of the second magnetic steel, the two magnetic steels, the first low carbon steel plate and the second low carbon steel plate form a closed magnetic circuit structure, and the first low carbon steel plate and the second low carbon steel plate are used for gathering magnetic field to reduce magnetic leakage.

2. The magnetic blowout arc-extinguishing device according to claim 1, characterized in that: The whole structure of the first magnetic steel and the first low carbon steel plate is surrounded by a first insulation frame in front, back, left and right; the whole structure of the second magnetic steel and the second low carbon steel plate is surrounded by a second insulation frame in front, back, left and right; the left ends of the first insulation frame and the second insulation frame are connected by an insulation piece, the first insulation frame, the second insulation frame and the insulation piece form a U-shaped structure with a right opening, and the arc extinguishing grid is located inside the U-shaped structure and is attached to the first insulation frame, the second insulation frame and the insulation piece respectively.

3. The magnetic blowout arc-extinguishing device according to claim 2, characterized in that: The two magnetic steels, the first low carbon steel plate and the second low carbon steel plate are all cuboid structures, and the upper side, the lower side, the left side and the right side of the four are aligned respectively, the first insulation frame and the second insulation frame are both square frames, the insulation piece is a cuboid structure, the arc extinguishing grid is formed by a plurality of cuboid sheets with the same size arranged uniformly in up-down direction, the upper side of the arc extinguishing grid is lower than the upper side of the two magnetic steels, the first low carbon steel plate and the second low carbon steel plate, the lower side of the arc extinguishing grid is higher than the lower side of the two magnetic steels, the first low carbon steel plate and the second low carbon steel plate, and the arc extinguishing grid is located in the left half of the space formed between the two magnetic steels.

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