Medium-voltage direct-current arc extinguishing system

Abstract

The invention relates to the technical field of medium-voltage direct-current arc extinguishing, and particularly discloses a medium-voltage direct-current arc extinguishing system which is used in cooperation with a contact system. Comprising an arc extinguish chamber, two groups of permanent magnet blow-out devices which are symmetrically arranged and have opposite magnetic poles, two groups of flash barriers which are arranged in one-to-one correspondence with the permanent magnet blow-out devices and are matched with the permanent magnet blow-out devices in an inserting manner, and an insulating frame provided with a hollow cavity, an opening is formed in one side, close to the arc extinguish chamber, of the hollow cavity; the two permanent magnet blow-out devices are installed on the outer side face of the arc extinguish chamber and located in the hollow cavity, and the two flash barriers are arranged on the sides, away from each other, of the two permanent magnet blow-out devices and located in the hollow cavity. According to the invention, the contact system can still realize an effective switching-on and switching-off function in a severe working environment, and the contact system has good shock vibration resistance and insulativity.

Description

Technical Field

[0001] The present invention relates to the technical field of medium voltage direct current arc extinguishing, and more particularly to a medium voltage direct current arc extinguishing system. Background Art

[0002] Medium voltage DC technology has been widely used in power systems, industrial production, ships and other fields because it can effectively solve problems such as long transmission distances, complex networks, and voltage stability. As a key device to ensure the safe and reliable operation of the power supply system, medium voltage DC circuit breakers are also constantly innovating and developing. Compared with AC systems, there is no zero point in the DC system current, so it is more difficult to break a DC circuit breaker. Effective DC breaking has always been one of the bottlenecks in the development of DC power grids.

[0003] The medium voltage DC circuit breaker used in the ship operating environment is not only required to be able to effectively break the circuit, but also required to have good vibration resistance and insulation. However, the prior art lacks a medium voltage DC arc extinguishing system that is able to effectively break the circuit, and also required to have good vibration resistance and insulation. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a medium voltage DC arc extinguishing system, so that the contact system can still achieve the effective breaking function in a harsh working environment and has good impact resistance and insulation.

[0005] The solution adopted by the present invention to solve the technical problem is:

[0006] A medium voltage DC arc extinguishing system is used in conjunction with a contact system; it comprises an arc extinguishing chamber, two sets of permanent magnetic blowing devices which are symmetrically arranged and have opposite magnetic poles, two sets of arc isolating plates which are arranged one by one corresponding to the permanent magnetic blowing devices and are plug-in matched, and an insulating frame provided with a hollow cavity; an opening is provided on one side of the hollow cavity close to the arc extinguishing chamber;

[0007] The two groups of permanent magnet magnetic blowing devices are installed on the outer side of the arc extinguishing chamber and are located in the hollow cavity. The two groups of arc isolation plates are arranged on the side away from the two groups of permanent magnet magnetic blowing devices and are located in the hollow cavity.

[0008] In some possible implementations, the insulating frame includes a front plate, a rear plate arranged parallel to the front plate, a support plate arranged between the front plate and the rear plate, and a top plate installed on the front plate and the rear plate; the top plate is located above the support plate; the opening is arranged on the top plate;

[0009] A limiting groove is provided on the support plate for installing an arc isolation plate and limiting the arc isolation plate in the Y-axis direction, one end of the arc isolation plate passes through the hollow cavity and is located in the limiting groove; the length of the arc isolation plate along the X-axis direction is adapted to the length of the hollow cavity along the X-axis direction.

[0010] In some possible implementations, the insulating frame further includes a bottom plate for fixing the front plate and the rear plate; a placement cavity for placing the contact system is formed between the bottom plate and the support plate;

[0011] The support plate, top plate and arc isolation plate cooperate with each other to form a hollow cavity. The moving contact and the stationary contact of the contact system pass through the support plate and extend into the hollow cavity. A gap is formed between the moving contact and the stationary contact and the arc isolation plate.

[0012] In some possible embodiments, the permanent magnet magnetic blowing device includes a magnetic conductive plate installed on the arc extinguishing chamber and provided with a mounting boss at the bottom, a permanent magnet installed on the mounting boss, and an insulating cover installed on the outer surface of the magnetic conductive plate and cooperating with the outer surface of the arc extinguishing chamber to enclose the permanent magnet; the magnetic poles of the permanent magnets in the two groups of permanent magnet magnetic blowing devices are in opposite directions.

[0013] In some possible implementations, the arc isolation plate is provided with a slot for inserting the arc extinguishing chamber extending into the hollow cavity portion, the mounting boss and the insulating cover.

[0014] In some possible embodiments, the arc extinguishing chamber includes a main body having an arc extinguishing cavity, multiple groups of partitions installed in the arc extinguishing cavity and dividing the arc extinguishing cavity into multiple arc zones, a grid assembly installed in each arc zone, a moving arc striking angle installed in the arc extinguishing cavity and connected to the moving contact, and a static arc striking angle installed in the arc extinguishing cavity and connected to the static contact.

[0015] In some possible implementations, a moving connecting piece connecting the moving arc striking angle and the moving contact is provided on the top plate; and a static connecting piece connecting the static arc striking angle and the static contact is provided on the top plate.

[0016] In some possible implementations, the grid assembly includes multiple groups of metal grids arranged in parallel and perpendicular to the partitions, and multiple groups of insulating grids arranged one-to-one with the metal grids; the insulating grids are located above the metal grids and are staggered at the bottom; the bottoms of the multiple groups of metal grids in each arc area are V-shaped;

[0017] The axis of the dynamic connecting piece, the axis of the static connecting piece and the vertex of the V-shaped structure are on the same vertical plane.

[0018] In some possible implementations, the main body includes two groups of symmetrically arranged side plates for mounting permanent magnet magnetic blowing devices, and end plates respectively connected to the ends of the two groups of side plates and forming an arc extinguishing cavity; the two groups of permanent magnet magnetic blowing devices are mounted on the outer sides of the side plates;

[0019] The side plates are arranged in parallel with the grid plate assembly; the dynamic arc striking angle and the static arc striking angle are arranged between the two groups of side plates.

[0020] In some possible implementations, two groups of ribs are provided on the top plate and are respectively in contact with the inner side surfaces of the side plates.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention has the characteristics of high arc extinguishing ability and strong insulation performance;

[0023] The insulating frame of the present invention has the characteristics of compact structure, high strength and high insulation;

[0024] The present invention can be widely used in switchgear such as medium voltage DC circuit breakers and load switches. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0026] Figure 2 is a cross-sectional view of the present invention;

[0027] Figure 3 It is a schematic diagram of the three-dimensional structure of the arc extinguishing chamber in the present invention;

[0028] Figure 4 It is a structural schematic diagram of the partition plate, grid plate assembly, dynamic arc-starting angle, and static arc-starting angle in the present invention;

[0029] Figure 5 It is a structural schematic diagram of the permanent magnet magnetic blowing device in the present invention;

[0030] Figure 6 It is a structural schematic diagram of the insulating frame in the present invention;

[0031] Figure 7 for Figure 6 The enlarged view of point A in the middle;

[0032] Wherein: 1-arc extinguishing chamber, 11-end plate, 12-side plate, 13-middle partition plate, 14-dynamic arc striking angle, 15-static arc striking angle, 16-metal grid, 17-insulating grid, 2-permanent magnet magnetic blowing device, 21-insulating cover, 22-permanent magnet, 23-magnetic conductive plate, 231-mounting boss, 3-arc isolation plate, 31-slot, 4-insulating frame, 41-front plate, 42-rear plate, 43-bottom plate, 44-support plate, 45-top plate, 451-rib, 46-hollow cavity, 47-placing cavity, 5-connecting plate, 51-dynamic connecting plate, 52-static connecting plate. DETAILED DESCRIPTION

[0033] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral body; it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. The "first", "second" and similar words mentioned in this application do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, "one" or "one" and other similar words do not indicate a quantity restriction, but indicate the existence of at least one. In the implementation of this application, "and / or" describes the association relationship of the associated objects, indicating that there can be three relationships, for example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In the description of the embodiments of the present application, unless otherwise specified, the meaning of "multiple" refers to two or more. For example, multiple positioning columns refer to two or more positioning columns. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] The present invention is described in detail below.

[0035] like Figure 1-Figure 7 As shown:

[0036] A medium voltage DC arc extinguishing system, used in conjunction with a contact system; comprising an arc extinguishing chamber 1, two sets of permanent magnetic blowing devices 2 which are symmetrically arranged and have opposite magnetic poles, two sets of arc isolating plates 3 which are arranged one-to-one with the permanent magnetic blowing devices 2 and are plug-in matched, and an insulating frame provided with a hollow cavity 46; the hollow cavity 46 is provided with an opening on one side close to the arc extinguishing chamber 1;

[0037] The two groups of permanent magnet magnetic blowing devices 2 are installed on the outer surface of the arc extinguishing chamber 1 and are located in the hollow cavity 46 . The two groups of arc isolation plates 3 are arranged on the side away from the two groups of permanent magnet magnetic blowing devices 2 and are located in the hollow cavity 46 .

[0038] In the present invention, the contact system is installed on the insulating frame, the arc extinguishing chamber 1 is installed on the insulating frame, and the permanent magnetic blowing device 2 is installed on the outside of the arc extinguishing chamber 1 and extends into the hollow cavity 46; the moving contact and the static contact of the contact system will extend into the hollow cavity 46 and be located between the two sets of permanent magnetic blowing devices 2; after the arc is generated on the moving contact and the static contact, it enters the arc extinguishing chamber 1, and the arc moves upward under the magnetic field force of the permanent magnetic blowing device 2 to extinguish the arc, and the arc is extinguished;

[0039] The arc isolation plate 3 can effectively isolate the arc and make the arc move upward in the hollow cavity 46 under the action of the magnetic field force of the permanent magnetic blowing device 2 to extinguish the arc.

[0040] In some possible implementations, the insulating frame 4 includes a front plate 41, a rear plate 42 arranged parallel to the front plate 41, a support plate 44 arranged between the front plate 41 and the rear plate 42, and a top plate 45 installed on the front plate 41 and the rear plate 42; the top plate 45 is located above the support plate 44; the opening is arranged on the top plate 45;

[0041] Specifically, the front plate 41 adopts an X-shaped rib plate to strengthen the plate body, and the rear plate 42 adopts an H-shaped rib plate to strengthen the plate body, which can withstand greater impact vibration. The support plate 44 is provided with multiple groups of grooves to reduce weight. At the same time, the connection between the contacts (moving contacts, static contacts) and the arc extinguishing chamber 1 is realized by providing a connecting piece 5 on the support sheet to increase the creepage distance; the multiple groups of grooves are arranged along the X-axis direction;

[0042] A limiting groove for mounting the arc isolation plate 3 and limiting the arc isolation plate 3 in the Y-axis direction is provided on the support plate 44, one end of the arc isolation plate 3 passes through the hollow cavity 46 and is located in the limiting groove; the length of the arc isolation plate 3 along the X-axis direction is adapted to the length of the hollow cavity 46 along the X-axis direction; the limiting groove is arranged in parallel with the groove;

[0043] The limiting groove is mainly used to limit the mutual movement of each group of arc isolation plates 3 in the Y-axis direction, and at the same time, the movement of the arc isolation plates 3 in the X-axis direction is limited by adapting the length of the arc isolation plates 3 in the X-axis direction to the length of the hollow cavity 46 in the X-axis direction, thereby effectively positioning the assembly position of the permanent magnet magnetic blowing device 2; when installing the arc isolation plates 3, the arc isolation plates 3 can be directly passed through the hollow cavity 46 along the Z-axis direction and inserted into the limiting groove;

[0044] The insulating frame 4 further includes a bottom plate 43 for fixing the front plate 41 and the rear plate 42; a placement cavity 47 for placing the contact system is formed between the bottom plate 43 and the support plate 44;

[0045] The support plate 44, the top plate 45, and the arc-isolating plate 3 cooperate with each other to form a hollow cavity 46. The moving contact and the stationary contact of the contact system pass through the support plate 44 and extend into the hollow cavity 46. A gap is formed between the moving contact and the stationary contact and the arc-isolating plate 3. This prevents arc escape during disconnection, thereby improving the insulation and disconnection reliability of the present invention.

[0046] The contact system is installed in the placement cavity 47. The moving contact and the static contact will pass through the support plate 44 and be located in the hollow cavity 46 and connected to the arc extinguishing chamber 1. After the arc is generated on the moving contact and the static contact, it enters the arc extinguishing chamber 1 for arc extinguishing under the action of the permanent magnet magnetic blowing device 2.

[0047] In some possible implementations, in order to effectively allow the arc to move upward into the arc extinguishing chamber 1 through the permanent magnet magnetic blowing device 2; the permanent magnet magnetic blowing device 2 includes a magnetic conductive plate 23 installed on the arc extinguishing chamber 1 and provided with a mounting boss 231 at the bottom, a permanent magnet 22 installed on the mounting boss 231, and an insulating cover 21 installed on the outer surface of the magnetic conductive plate 23 and cooperating with the outer side surface of the arc extinguishing chamber 1 to seal the permanent magnet 22; the magnetic poles of the permanent magnets 22 in the two groups of permanent magnet magnetic blowing devices 2 are opposite in direction; the mounting boss 231 is located at the bottom of the magnetic conductive plate 23 and at the middle position of the magnetic conductive plate 23;

[0048] The magnetic conductive plate 23 is installed on the outside of the arc extinguishing chamber 1, the permanent magnet 22 is embedded in the magnetic conductive plate 23, the insulating cover 21 is installed on the side of the magnetic conductive plate 23 away from the arc extinguishing chamber 1, and cooperates with the arc extinguishing chamber 1 to seal the permanent magnet 22; the permanent magnets 22 of the two groups of permanent magnet magnetic blowing devices 2 have opposite magnetic poles to generate magnetic field force, under the action of this magnetic field force, the arc entering the arc extinguishing chamber 1 will move upward to extinguish the arc.

[0049] In some possible implementations, a slot 31 for inserting the portion of the arc extinguishing chamber 1 extending into the hollow cavity 46 , the mounting boss 231 and the insulating cover 21 is provided on the arc isolation plate 3 .

[0050] The arrangement of the slot 31 ensures that the generated arc will be completely isolated.

[0051] In some possible embodiments, the arc extinguishing chamber 1 includes a main body having an arc extinguishing cavity, multiple groups of partitions installed in the arc extinguishing cavity and dividing the arc extinguishing cavity into multiple arc zones, a grid assembly installed in each arc zone, a moving arc striking angle 14 installed in the arc extinguishing cavity and connected to the moving contact, and a static arc striking angle 15 installed in the arc extinguishing cavity and connected to the static contact; the grid assembly includes multiple groups of metal grids 16 arranged in parallel and perpendicular to the partitions, and multiple groups of insulating grids 17 arranged one-to-one with the metal grids 16; the metal grids 16 are made of ferromagnetic material, have good arc absorption performance and divide the arc into several short arcs, and the insulating grids 17 lengthen the short arc to further increase the arc pressure of the divided arc, which is beneficial to arc extinction.

[0052] After the arc is generated on the moving contact and the static contact of the circuit breaker, it is introduced into the corresponding moving arc striking angle 14 and the static arc striking angle 15, and enters the arc extinguishing chamber 11. The arc moves upward under the magnetic field force of the permanent magnetic blowing device 2, and is divided into multiple groups by the partition, and enters each arc zone respectively;

[0053] The arc enters the metal grid 16 and is divided into several short arcs by the metal grid 16. After the arc is deionized by the metal grid 16, the arc voltage increases and continues to move upward.

[0054] When the arc moves to the junction of the metal grid 16 and the insulating grid 17, the arc root stays on the metal grid 16, the arc is pulled into the insulating grid 17, the arc column gradually becomes thinner, and the arc voltage further increases. When the power supply voltage cannot maintain the arc voltage, the arc is extinguished.

[0055] Furthermore, in order to allow the arc generated by the moving contact and the static contact to enter the arc extinguishing chamber 1 and increase the creepage distance, a moving arc striking angle 14 and a moving connecting piece 51 connecting the moving contact are provided on the top plate 45; and a static arc striking angle 15 and a static connecting piece 52 connecting the static contact are provided on the top plate 45.

[0056] Furthermore, in order to effectively achieve rapid arc extinguishing, the insulating grids 17 are located above the metal grids 16 and the bottoms are staggered; the bottoms of the multiple groups of metal grids 16 in each arc zone are V-shaped; the design of the V-shaped structure can optimize the electric field distribution, so that the arc is more evenly and effectively constrained during the formation and diffusion process; this optimized electric field distribution helps to reduce the intensity and stability of the arc, thereby making it easier to achieve arc extinguishing;

[0057] The axis of the dynamic connecting piece 51, the axis of the static connecting piece 52 and the vertex of the V-shaped structure are on the same vertical plane.

[0058] In some possible implementations, the main body includes two groups of symmetrically arranged side plates 12 for mounting permanent magnet magnetic blowing devices 2, and end plates 11 respectively connected to the ends of the two groups of side plates 12 to form an arc extinguishing cavity; the two groups of permanent magnet magnetic blowing devices 2 are mounted on the outer surfaces of the side plates 12; the arc extinguishing cavity formed has openings at the top and bottom;

[0059] The side plates 12 are arranged in parallel with the grid assembly; the dynamic arc striking angle 14 and the static arc striking angle 15 are arranged between the two groups of side plates 12.

[0060] In some possible embodiments, a mounting groove is provided on the outer surface of the side panel 12, the magnetic conductive plate 23 will be installed in the mounting groove, a protrusion is provided at the bottom of the side panel 12, a pit connected to the mounting groove is provided on the protrusion, the mounting boss 231 will be installed in the pit, and the protrusion will be located in the hollow cavity 46.

[0061] Preferably, there are five groups of partitions, which divide the arc extinguishing chamber into six arc zones, each of which is equipped with a grid assembly; there is a gap between two adjacent groups of metal grids 16, and the gap is 3-5 mm.

[0062] Furthermore, two groups of ribs 451 are provided on the top plate 45, which are in contact with the inner side surfaces of the side plates 12 respectively; this arrangement is used to effectively locate the installation position of the arc extinguishing chamber 1; a long groove for installing the dynamic connecting piece 51 and the static connecting piece 52 is provided between the two groups of ribs 451; one end of the long groove is connected to the hollow cavity 46, and the axis of the long groove, the axis of the dynamic connecting piece 51, the axis of the static connecting piece 52 and the vertex of the V-shaped structure are on the same vertical plane; the cooperation between the ribs 451 and the side plates 12, the cooperation between the slots 31 and the protrusions and the mounting bosses 231 on the arc isolation plate 3, make them more firmly connected to each other, and effectively enhance the impact and vibration resistance of the arc extinguishing chamber 1;

[0063] Furthermore, the protrusion is disposed at the middle portion of the side plate 12 along the X-axis direction, so that the permanent magnet 22 will also be located at the middle position.

[0064] Furthermore, the arc extinguishing chamber 1 is tightly fixed to the top plate 45 by fasteners; and the magnetic conductive plate is fixed to the side plate 12 by screws.

[0065] The present invention is not limited to the above-mentioned specific embodiments, but extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims

1. A medium voltage DC arc extinguishing system, characterized in that: It includes an arc extinguishing chamber, two sets of permanent magnetic blowing devices which are symmetrically arranged and have opposite magnetic poles, two sets of arc-isolating plates which are arranged one by one corresponding to the permanent magnetic blowing devices and are plug-in matched, and an insulating frame provided with a hollow cavity; an opening is provided on one side of the hollow cavity close to the arc extinguishing chamber; The two groups of permanent magnet magnetic blowing devices are installed on the outer side of the arc extinguishing chamber and are located in the hollow cavity. The two groups of arc isolation plates are arranged on the side away from the two groups of permanent magnet magnetic blowing devices and are located in the hollow cavity.

2. A medium voltage DC arc extinguishing system according to claim 1, characterized in that: The insulating frame comprises a front plate, a rear plate arranged parallel to the front plate, a support plate arranged between the front plate and the rear plate, and a top plate installed on the front plate and the rear plate; the top plate is located above the support plate; the opening is arranged on the top plate; A limiting groove is provided on the support plate for installing an arc isolation plate and limiting the arc isolation plate in the Y-axis direction, one end of the arc isolation plate passes through the hollow cavity and is located in the limiting groove; the length of the arc isolation plate along the X-axis direction is adapted to the length of the hollow cavity along the X-axis direction.

3. A medium voltage DC arc extinguishing system according to claim 2, characterized in that: The insulating frame also includes a bottom plate for fixing the front plate and the rear plate; a placement cavity for placing the contact system is formed between the bottom plate and the support plate; The support plate, top plate and arc isolation plate cooperate with each other to form a hollow cavity. The moving contact and the stationary contact of the contact system pass through the support plate and extend into the hollow cavity. A gap is formed between the moving contact and the stationary contact and the arc isolation plate.

4. A medium voltage DC arc extinguishing system according to claim 1, characterized in that: The permanent magnet magnetic blowing device comprises a magnetic conductive plate installed on the arc extinguishing chamber and provided with a mounting boss at the bottom, a permanent magnet installed on the mounting boss, and an insulating cover installed on the outer surface of the magnetic conductive plate and cooperating with the outer surface of the arc extinguishing chamber to seal the permanent magnet; the magnetic poles of the permanent magnets in the two groups of permanent magnet magnetic blowing devices are in opposite directions.

5. A medium voltage DC arc extinguishing system according to claim 4, characterized in that: The arc isolation plate is provided with a slot for inserting the arc extinguishing chamber extending into the hollow cavity part, the mounting boss and the insulating cover.

6. A medium voltage DC arc extinguishing system according to claim 2, characterized in that: The arc extinguishing chamber includes a main body with an arc extinguishing cavity, multiple groups of partitions installed in the arc extinguishing cavity and dividing the arc extinguishing cavity into multiple arc zones, a grid assembly installed in each arc zone, a moving arc striking angle installed in the arc extinguishing cavity and connected to a moving contact, and a static arc striking angle installed in the arc extinguishing cavity and connected to a static contact.

7. A medium voltage DC arc extinguishing system according to claim 6, characterized in that: A moving connecting piece connecting the moving arc striking angle and the moving contact is arranged on the top plate; and a static connecting piece connecting the static arc striking angle and the static contact is arranged on the top plate.

8. A medium voltage DC arc extinguishing system according to claim 7, characterized in that: The grid assembly includes multiple groups of metal grids arranged in parallel and perpendicular to the partitions, and multiple groups of insulating grids arranged one by one corresponding to the metal grids; the insulating grids are located above the metal grids and are arranged in a staggered manner at the bottom; the bottoms of the multiple groups of metal grids in each arc area are in a V-shaped structure; The axis of the dynamic connecting piece, the axis of the static connecting piece and the vertex of the V-shaped structure are on the same vertical plane.

9. A medium voltage DC arc extinguishing system according to claim 6, characterized in that: The main body comprises two sets of symmetrically arranged side plates for mounting permanent magnet magnetic blowing devices, and end plates respectively connected to the ends of the two sets of side plates and forming an arc extinguishing cavity; the two sets of permanent magnet magnetic blowing devices are mounted on the outer sides of the side plates; The side plates are arranged in parallel with the grid plate assembly; the dynamic arc striking angle and the static arc striking angle are arranged between the two groups of side plates.

10. A medium voltage DC arc extinguishing system according to claim 8, characterized in that: Two groups of ribs are arranged on the top plate and are respectively in contact with the inner side surfaces of the side plates.

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