Arc extinguishing device for ring network cabinet

Abstract

The present invention relates to the technical field of ring network cabinets, and discloses an arc extinguishing device for a ring network cabinet, wherein the arc extinguishing device comprises a mounting seat, a plurality of arc extinguishing grids and an adjusting member; the plurality of arc extinguishing grids are mounted in the mounting seat to form a plurality of connected arc extinguishing chambers, the arc extinguishing grids are magnetic conductors, the arc extinguishing grids have a flat section and a corrugated section, the flat section is arranged on the arc entry side of the arc extinguishing chamber, and a plurality of groups of flame retardant strips are symmetrically arranged on the flat section on opposite sides of the inner wall of the arc extinguishing chamber, so as to form a plurality of arc entry channels on the flat section and connected to the corrugated section, so that when a short arc flows through the corrugated section from the arc entry channel, the trough of the corrugated section lengthens the short arc, and the crest of the corrugated section shortens the short arc, so that the short arc continuously reduces the electric field strength in the arc when it is alternately lengthened, so as to enhance the recombination and diffusion of ions and accelerate the extinction of the short arc. The arc extinguishing device of the present invention has a simple structure and is easy to operate, and can effectively ensure the arc extinguishing effect and improve safety by designing a two-stage arc extinguishing structure.

Description

Technical Field

[0001] The invention relates to the technical field of ring network cabinets, and in particular to an arc extinguishing device used for a ring network cabinet. Background Art

[0002] Ring main unit is a set of electrical equipment with high-voltage switchgear installed in a steel plate metal cabinet or assembled into a spaced ring main unit. The load switch is prone to arcing during the opening and closing process, which may damage the surrounding components; therefore, it is usually necessary to extinguish the arc on the high-voltage circuit switch to prevent the arc from affecting the safe operation of the power supply system. For example, the arc generated on the switch contact prolongs the time for the short-circuit current to pass through the circuit, causing significant losses due to untimely shutdown of the equipment, and the high temperature of the arc may burn the switch contacts.

[0003] The most commonly used arc extinguishing device at present is the vacuum interrupter, which mainly uses the excellent insulation of vacuum to prevent arcs from occurring in medium and high voltage circuits during the power-on process. However, due to the need for vacuuming, it is cumbersome to use, and the vacuum degree cannot be guaranteed during use. If a small crack occurs in the vacuum interrupter and air enters, it is impossible to judge whether it is reliable in time and perform the closing operation, which is very likely to cause danger due to the generated arc sparks. Summary of the invention

[0004] In view of this, an object of the present invention is to provide an arc extinguishing device for a ring main unit to solve the technical problems mentioned in the prior art.

[0005] An arc extinguishing device for a ring main unit, the arc extinguishing device comprising:

[0006] The mounting seat is a U-shaped structure, and a plurality of sockets are arranged side by side along the opening direction inside the mounting seat;

[0007] A plurality of arc-extinguishing grids are arranged in the mounting seat, and one end of the plurality of arc-extinguishing grids are detachably mounted in the plurality of sockets in a one-to-one correspondence, so as to form a plurality of connected arc-extinguishing chambers in the mounting seat, and the arc-extinguishing grids are magnetic conductors, and are used to magnetically attract the long arc generated at the switch contact into the plurality of arc-extinguishing chambers and divide them into a plurality of short arcs connected in series;

[0008] The arc extinguishing grid has a flat section and a corrugated section, and the flat section is arranged on the arc-entry side of the arc extinguishing chamber, and a plurality of groups of flame-retardant strips are symmetrically arranged on opposite sides of the inner wall of each arc extinguishing chamber and located on the flat section, and the plurality of groups of flame-retardant strips are arranged side by side along the extension direction of the flat section to form a plurality of arc-entry channels on the flat section, and the arc-exit side of each arc-entry channel is respectively connected to the corrugated section, so that when a short arc flows from the arc-entry channel through the corrugated section, the trough of the corrugated section lengthens the short arc, and the crest of the corrugated section shortens the short arc;

[0009] An adjusting member is used to adjust the distance between the corresponding sockets according to the current difference of the short arcs in any of the arc extinguishing chambers to change the width of the corresponding arc extinguishing chamber to lengthen / shorten the short arc. Different widths of the arc extinguishing chambers will cause different interference intensities to the short arc, and the width of the arc extinguishing chamber is adjusted in real time as the interference intensity of the short arc changes dynamically to change the recombination and diffusion rate of ions around the short arc and accelerate the extinction of the short arc.

[0010] Preferably, the adjusting member has:

[0011] A plurality of fixing plates, each of which is arranged in one-to-one correspondence with each of the plurality of arc-extinguishing grids. The fixing plates are slidably mounted on the mounting seat, and elastic members are respectively arranged between two adjacent fixing plates to connect the fixing plates in parallel in series. The socket is arranged on a side of the fixing plate close to the arc-extinguishing grid;

[0012] Each of the fixing plates is provided with a mounting hole along its moving direction, and the mounting holes on the fixing plates are respectively arranged on the same axis;

[0013] An electromagnet is installed in the installation hole, and each of the electromagnets is electrically connected to the arc extinguishing grid corresponding to its position, so as to supply power to the electromagnet when a short arc flows through the arc extinguishing chamber.

[0014] Preferably, the mounting seat has a limiting groove for accommodating the fixing plate, a fixing rod is arranged in the limiting groove, and a plurality of fixing plates are respectively sleeved on the outer circumference of the fixing rod;

[0015] The inner wall of the mounting seat and the outer circumference of the fixing rod are coated with a flame retardant thermal conductive insulating coating.

[0016] Preferably, the fixing plate is an I-shaped structure, so that isolation zones are formed between the corrugated section and the mounting seat at two opposite sides of the middle of the fixing plate;

[0017] The socket is arranged on the horizontal connecting section of the fixing plate.

[0018] Preferably, the elastic member is a spring, the spring is sleeved on the outer circumference of the fixing rod, and two adjacent springs have the same size and deformation.

[0019] Preferably, the corrugated section of the arc-extinguishing grid has at least two corrugation valleys.

[0020] Preferably, the flame retardant strip is a nylon strip.

[0021] Preferably, the flame retardant strip is detachably mounted on the flat section.

[0022] Preferably, the flame retardant strip has a stepped structure.

[0023] Preferably, the mounting seat has a mounting portion for mounting the arc extinguishing device on one side of the switch contact.

[0024] The beneficial effects that the present invention can produce include:

[0025] 1. An arc extinguishing device for a ring network cabinet provided by the present invention divides the long arc generated at the switch contact by designing multiple arc extinguishing grids, so as to absorb each short arc into the arc extinguishing chamber, and separates the short arc in a single arc entry channel by a flame retardant strip, which can increase the effective contact area of ​​the short arc to cool the short arc; at the same time, when the short arc flows through the arc entry channel, the flame retardant strip will be burned to generate gas in the arc entry channel to increase the pressure on the arc entry side, thereby blowing the short arc to the corrugated section and playing the role of insulating arc extinguishing, so as to achieve the effect of primary arc extinguishing.

[0026] 2. The arc extinguishing device for a ring main unit provided by the present invention, when a short arc flows through a corrugated section, the trough of the corrugated section will lengthen the short arc, so that the electric field strength in the short arc is continuously reduced when the short arc is alternately lengthened, so as to enhance the recombination and diffusion of ions, accelerate the extinction of the short arc, and thus achieve the effect of secondary arc extinguishing.

[0027] 3. The arc extinguishing device for a ring main unit provided by the present invention supplies power to an adjusting component through the current in the arc when a short arc flows through an arc extinguishing chamber, so as to reduce the electric field strength of the arc. As adjacent short arcs are extinguished in the arc extinguishing chamber, a current difference is generated, so as to drive the adjusting component to adjust the distance between adjacent sockets to change the width of the arc extinguishing chamber to lengthen / shorten the short arc, thereby further enhancing the arc extinguishing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the arc extinguishing device in the present invention;

[0029] Figure 2 A schematic diagram of the arc extinguishing device in the present invention in a working state;

[0030] Figure 3 For the present invention Figure 1 Schematic diagram of the structure without the arc extinguishing grid;

[0031] Figure 4 It is a schematic diagram of the structure of the arc extinguishing grid and the fixing plate in the present invention;

[0032] Figure 5 It is a structural schematic diagram of the fixing plate and the adjusting member in the present invention;

[0033] Figure 6A schematic diagram of the arc being elongated / shortened in the corrugated section in the present invention;

[0034] In the figure: 1, mounting base, 2, socket, 3, arc extinguishing grid, 4, arc extinguishing chamber, 5, flat section, 6, corrugated section, 7, flame retardant strip, 8, arc entry channel, 9, fixing plate, 10, spring, 11, electromagnet, 12, limit groove, 13, fixing rod, 14, mounting part, 15, static contact, 16, moving contact, 17, arc. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] See also Figure 1-Figure 5 As shown, the present invention provides an arc extinguishing device for a ring network cabinet, the arc extinguishing device comprising a mounting seat 1, a plurality of arc extinguishing grids 3 and an adjusting member; wherein the mounting seat 1 is an insulating shell of a U-shaped structure, wherein a plurality of groups of sockets 2 are arranged side by side along the opening direction inside the mounting seat 1; a plurality of arc extinguishing grids 3 are arranged in the mounting seat 1, and one ends of the plurality of arc extinguishing grids 3 are detachably installed in the plurality of groups of sockets 2 in a one-to-one correspondence, so as to form a plurality of connected arc extinguishing chambers 4 in the mounting seat 1, the arc extinguishing grids 3 are magnetic conductors, preferably steel sheets, which are used to magnetically attract the long arcs generated at the switch contacts into the plurality of arc extinguishing chambers 4 and divide them into a plurality of short arcs connected in series; the arc extinguishing grids 3 have a flat section 5 and a corrugated section 6, and the flat section 5 is arranged on the arc-entry side of the arc extinguishing chamber 4, and a plurality of groups of flame retardant strips 7 are symmetrically arranged on opposite sides of the inner wall of each arc extinguishing chamber 4 and on the flat section 5, and the plurality of groups of flame retardant strips 7 are arranged along the flat section 5. The extension direction is arranged side by side to form multiple arc entry channels 8 on the flat section 5, and the arc exit side of each arc entry channel 8 is respectively connected to the corrugated section 6, so that when the short arc flows through the corrugated section 6 from the arc entry channel 8, the trough of the corrugated section 6 will lengthen the short arc, and the crest of the corrugated section 6 will shorten the short arc. When the short arc is alternately lengthened, the electric field strength in the arc is continuously reduced to enhance the recombination and diffusion of ions and accelerate the extinction of the short arc; the adjustment member is used to adjust the distance between the corresponding sockets 2 according to the current difference of the short arcs in any several arc extinguishing chambers 4 to change the width of the corresponding arc extinguishing chamber 4 to lengthen / shorten the short arc. Different widths of the arc extinguishing chamber 4 have different interference intensities on the short arc, and the width of the arc extinguishing chamber 4 is adjusted in real time with the dynamic change of the interference intensity of the short arc to change the recombination and diffusion rate of ions around the short arc, thereby further accelerating the extinction of the short arc.

[0037] In the above, in order to solve the problems of complicated operation and low safety of the conventional vacuum arc extinguishing chamber during high-voltage arc extinguishing, the present invention divides the long arc generated at the switch contact by designing a plurality of arc extinguishing grids 3, so as to absorb each short arc into the arc extinguishing chamber 4, and separates the short arc into a single arc entry channel 8 by the flame retardant strip 7, thereby increasing the effective contact area of ​​the short arc to cool the short arc; at the same time, when the short arc flows through the arc entry channel 8, the flame retardant strip 7 will be burned to generate gas in the arc entry channel 8 to increase the pressure on the arc entry side, thereby blowing the short arc to the corrugated section 6 and achieving the effect of insulating arc extinguishing, so as to achieve the effect of primary arc extinguishing; Figure 6 As shown, when the short arc flows through the corrugated section 6, the trough of the corrugated section 6 will lengthen the short arc, so that the short arc continuously reduces the electric field strength in the arc when it is alternately lengthened, so as to enhance the recombination and diffusion of ions and accelerate the extinction of the short arc, thereby achieving the effect of secondary arc extinguishing. Among them, when the short arc flows through the arc extinguishing chamber 4, the regulating member is powered by the current in the arc to reduce the electric field strength of the arc, and as the adjacent short arcs are extinguished in the arc extinguishing chamber 4, a current difference is generated to drive the regulating member to adjust the distance between the adjacent sockets 2 to change the width of the arc extinguishing chamber 4 to lengthen / shorten the short arc, which can further enhance the arc extinguishing effect. The arc extinguishing device of the present invention has the advantages of simple structure and convenient operation, and by designing a two-stage arc extinguishing structure, it can effectively ensure the arc extinguishing effect and improve safety.

[0038] Furthermore, the adjusting member has a plurality of fixing plates 9, which are respectively arranged in one-to-one correspondence with the plurality of groups of arc-extinguishing grids 3. The fixing plates 9 are slidably mounted on the mounting seat 1, and elastic members are respectively arranged between two adjacent fixing plates 9 to connect the plurality of fixing plates 9 in series in parallel; the socket 2 is arranged on the side of the fixing plate 9 close to the arc-extinguishing grid 3 to facilitate plug-in installation of the arc-extinguishing grid 3, wherein the arc-extinguishing grid 3 and the socket 2 have an interference fit; each fixing plate 9 is provided with a mounting hole along its moving direction, and the mounting holes on the plurality of fixing plates 9 are respectively arranged on the same axis; an electromagnet 11 is installed in the mounting hole, and each electromagnet 11 is respectively electrically connected to the arc-extinguishing grid 3 corresponding to its position to power the electromagnet 11 when a short arc flows through the arc-extinguishing chamber 4. Specifically, when the electromagnet 11 is energized, the two adjacent fixed plates 9 will be attracted to each other, and the electromagnet 11 that is energized first will reduce the distance between the two adjacent fixed plates 9, while the distance between the other fixed plates 9 remains almost unchanged under the tension of the elastic member. Therefore, the widths of multiple arc extinguishing chambers 4 can be adjusted to be inconsistent to change the length of the short arc; and the arc generated at the switch contact is almost sucked into the arc extinguishing chamber 4 from the middle to both sides in sequence, so that the width of the multiple arc extinguishing chambers 4 gradually increases from the center to both sides, which can quickly lengthen the short arcs sucked in on both sides, accelerate the arc extinguishing effect of the arcs on both sides, so as to quickly disconnect the arc from the switch contact, and avoid significant losses caused by untimely disconnection of the switch contacts.

[0039] Furthermore, the mounting seat 1 has a limiting groove 12 for accommodating the fixing plate 9, and a fixing rod 13 is detachably installed in the limiting groove 12. A plurality of fixing plates 9 are respectively sleeved on the outer periphery of the fixing rod 13 to slide along the central axis direction of the fixing rod 13; the inner wall of the mounting seat 1 and the outer periphery of the fixing rod 13 are coated with a flame-retardant thermally conductive insulating coating to prevent the arc from burning the mounting seat 1 and the fixing rod 13 when flowing through the arc extinguishing chamber 4, thereby improving the service life of the arc extinguishing equipment and ensuring its heat dissipation performance; in this embodiment, the flame-retardant thermally conductive insulating coating can be a high-insulation fluorosilicone rubber coating specially used for reactors. In the above, the fixing plate 9 is an "I"-shaped structure, and the socket 2 is provided on the horizontal connecting section of the fixing plate 9 to form an isolation zone between the corrugated section 6 and the mounting seat 1 on the opposite sides of the middle of the fixing plate 9, so as to prevent the short arc from flowing into the limiting groove 12 after the secondary arc extinguishing, causing damage to the mounting seat 1, such as breakdown, burning, etc. The elastic member is a spring 10 , which is sleeved on the outer circumference of the fixing rod 13 , and two adjacent springs 10 have the same size and deformation to ensure that the initial widths of the multiple arc extinguishing chambers 4 are the same.

[0040] Furthermore, the corrugated section 6 of the arc-extinguishing grid 3 has at least two troughs to improve the arc-extending arc-extinguishing effect.

[0041] Furthermore, the flame retardant strip 7 is a nylon strip, and the flame retardant strip 7 can be detachably installed on the flat section 5 so as to be replaced after wear and tear occurs; the structure of the flame retardant strip 7 is stepped so that part of the short electric arc can burn when flowing through the flame retardant strip 7 in the horizontal direction to form an insulating arc extinguishing.

[0042] Furthermore, the mounting base 1 has a mounting portion 14 for mounting the arc extinguishing device to one side of the switch contact; specifically, the mounting portion 14 includes two groups of connecting blades, which are respectively mounted on one side of the mounting base 1 away from the arc entry chamber, and each group of connecting blades is respectively provided with a number of connecting holes for fixing the connecting blades in the ring network cabinet through insulating columns.

Claims

1. An arc extinguishing device for a ring main unit, characterized in that: The arc extinguishing device comprises: The mounting seat (1) is a U-shaped structure, and a plurality of groups of sockets (2) are arranged side by side along the opening direction inside the mounting seat; A plurality of arc-extinguishing grids (3) are arranged in the mounting seat (1), and one end of the plurality of arc-extinguishing grids (3) is detachably mounted in a plurality of groups of the sockets (2) in a one-to-one correspondence, so as to form a plurality of connected arc-extinguishing chambers (4) in the mounting seat (1); the arc-extinguishing grids (3) are magnetic conductors, and are used to magnetically attract a long electric arc generated at a switch contact to the plurality of arc-extinguishing chambers (4) to divide the long electric arc into a plurality of short electric arcs connected in series; The arc extinguishing grid (3) comprises a flat section (5) and a corrugated section (6), and the flat section (5) is arranged on the arc entry side of the arc extinguishing chamber (4), and a plurality of groups of flame retardant strips (7) are symmetrically arranged on opposite sides of the inner wall of each arc extinguishing chamber (4) and located on the flat section (5), and the plurality of groups of flame retardant strips (7) are arranged side by side along the extension direction of the flat section (5) to form a plurality of arc entry channels (8) on the flat section (5), and the arc exit side of each arc entry channel (8) is respectively connected to the corrugated section (6), so that when a short arc flows from the arc entry channel (8) through the corrugated section (6), the trough of the corrugated section (6) lengthens the short arc, and the crest of the corrugated section (6) shortens the short arc; An adjusting member, used for adjusting the distance between the corresponding sockets (2) according to the current difference of the short arcs in any of the arc extinguishing chambers (4) to change the width of the corresponding arc extinguishing chamber (4) to lengthen / shorten the short arc, wherein different widths of the arc extinguishing chamber (4) have different interference intensities on the short arc, and the width of the arc extinguishing chamber (4) is adjusted in real time with the dynamic change of the interference intensity of the short arc to change the recombination and diffusion rate of ions around the short arc, thereby accelerating the extinction of the short arc; The adjusting member has: A plurality of fixing plates (9), wherein the plurality of fixing plates (9) are respectively arranged in one-to-one correspondence with the plurality of groups of arc-extinguishing grids (3), the fixing plates (9) are slidably mounted on the mounting seat (1), and elastic members are respectively arranged between two adjacent fixing plates (9) so as to connect the plurality of fixing plates (9) in parallel in series, and the socket (2) is arranged on a side of the fixing plate (9) close to the arc-extinguishing grid (3); Each of the fixing plates (9) is provided with a mounting hole along its moving direction, and the mounting holes on the plurality of fixing plates (9) are respectively arranged on the same axis; An electromagnet (11) is installed in the installation hole, and each of the electromagnets (11) is electrically connected to the arc extinguishing grid (3) corresponding to its position, so as to supply power to the electromagnet (11) when a short arc flows through the arc extinguishing chamber (4).

2. The arc extinguishing device for a ring main unit according to claim 1, characterized in that: The mounting seat (1) has a limiting groove (12) for accommodating the fixing plate (9), a fixing rod (13) is arranged in the limiting groove (12), and a plurality of fixing plates (9) are respectively sleeved on the outer circumference of the fixing rod (13); The inner wall of the mounting seat (1) and the outer periphery of the fixing rod (13) are both coated with a flame-retardant thermally conductive insulating coating.

3. The arc extinguishing device for a ring main unit according to claim 1, characterized in that: The fixing plate (9) is an I-shaped structure, so as to form isolation zones between the corrugated section (6) and the mounting seat (1) at two opposite sides of the middle of the fixing plate (9); The socket (2) is arranged on a horizontal connecting section of the fixing plate (9).

4. The arc extinguishing device for a ring main unit according to claim 2, characterized in that: The elastic member is a spring (10), the spring (10) is sleeved on the outer circumference of the fixing rod (13), and two adjacent springs (10) have the same size and deformation.

5. The arc extinguishing device for a ring main unit according to claim 1, characterized in that: The corrugated section (6) of the arc-extinguishing grid (3) has at least two corrugation valleys.

6. The arc extinguishing device for a ring main unit according to claim 1, characterized in that: The flame retardant strip (7) is a nylon strip.

7. The arc extinguishing device for a ring main unit according to claim 1, characterized in that: The flame retardant strip (7) is detachably mounted on the flattened section (5).

8. The arc extinguishing device for a ring main unit according to claim 1, characterized in that: The flame retardant strip (7) has a stepped structure.

9. The arc extinguishing device for a ring main unit according to claim 1, characterized in that: The mounting seat (1) is provided with a mounting portion (14) for mounting the arc extinguishing device on one side of a switch contact.

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