TWI795246B - Vacuum arc-extinguishing chamber and vacuum circuit breaker with a triggered cathode - Google Patents

Abstract

The present invention provides a vacuum arc-extinguishing chamber and vacuum circuit breaker with a triggered cathode, which pertains to the technical field of middle-high voltage vacuum switches. The vacuum arc-extinguishing chamber includes a static conductive rod, a moving conductive rod and electrode structure. The electrode structure includes a first electrode and a second electrode. The first electrode is disposed at the end surface of the static conductive rod close to the moving conductive rod. The second electrode is disposed at the end surface of the moving conductive rod close to the static conductive rod. The first electrode includes a first triggered cathode and a first transverse magnetic field contact piece. The first transverse magnetic field contact piece is disposed at the static conductive rod. The first triggered cathode is disposed at the arcing surface of the first transverse magnetic field contact piece. The second electrode includes a second triggered cathode and a second transverse magnetic field contact piece. The second transverse magnetic field contact piece is disposed at the moving conductive rod. The second triggered cathode is disposed at the arcing surface of the second transverse magnetic field contact piece. The first triggered cathode and the second triggered cathode are disposed corresponding to each other, which significantly increases the stability of the opening distance of pre-arcing contact gap of the vacuum arc-extinguishing chamber.

Description

Vacuum interrupter and vacuum circuit breaker units with triggered cathodes

The invention relates to the technical field of medium and high voltage vacuum switches, for example, to a vacuum interrupter and a vacuum circuit breaker device with trigger cathodes.

Due to the characteristics of high insulation performance, strong breaking capacity, long life, maintenance-free, and environmental friendliness, vacuum interrupters and vacuum circuit breakers are widely used in the field of medium-voltage power transmission and distribution as control and protection switches all over the world. . At the same time, in the high-current test station, the vacuum interrupter and the vacuum circuit breaker can also be used as the closing trigger switch. However, due to the uncertainty of the vacuum breakdown, when the vacuum interrupter and the vacuum circuit breaker are used as the closing trigger switch, the gap between the contacts when the vacuum interrupter has a pre-breakdown is quite different, which will affect The arcing time applied to the test object during the high current test affects the accuracy of the test.

The invention provides a vacuum interrupter and a vacuum circuit breaker device with a trigger cathode. When the vacuum interrupter is used as a closing trigger switch, the stability of the opening distance of the pre-breakdown gap of the closing contact gap of the vacuum interrupter is improved. sex.

The present invention provides the following technical means: A vacuum interrupter with a trigger cathode, including a static conductive rod and a dynamic conductive rod, and also includes: The electrode structure includes a first electrode and a second electrode, the first electrode is provided on an end surface of the static conductive rod close to the movable conductive rod, and the second electrode is provided on the end surface of the movable conductive rod close to the static conductive rod;

The first electrode includes a first trigger cathode and a first transverse magnetic field contact piece. curved surface;

The second electrode includes a second trigger cathode and a second transverse magnetic field contact piece. curved surface;

The first trigger cathodes are set in one-to-one correspondence with the second trigger cathodes.

As an optional form of the vacuum interrupter with a trigger cathode, the first trigger cathode and the second trigger cathode are ring-shaped structures, and are coaxially arranged with the static conductive rod and the movable conductive rod.

As an optional form of the vacuum interrupter with a trigger cathode, the first trigger cathode is recessed with a first annular discharge groove, and the second trigger cathode is recessed with a second annular discharge groove. The annular discharge grooves are provided in one-to-one correspondence with the second annular discharge grooves.

As an optional form of the vacuum interrupter with a triggered cathode, the longitudinal sections of the first annular discharge groove and the second annular discharge groove are both rectangular.

As an optional form of the vacuum interrupter with a triggered cathode, the longitudinal sections of the first annular discharge groove and the second annular discharge groove are both arc-shaped.

As an optional form of a vacuum interrupter with a trigger cathode, the arcing surface of the first transverse magnetic field contact piece is concavely provided with a first mounting groove, and the first trigger cathode is fixed to the first mounting groove by soldering. in the slot.

As an optional form of the vacuum interrupter with a trigger cathode, the arcing surface of the second transverse magnetic field contact piece is concavely provided with a second installation groove, and the second trigger cathode is fixed to the second installation by soldering. in the slot.

As an optional form of the vacuum interrupter with triggered cathodes, both the first transverse magnetic field contact piece and the second transverse magnetic field contact piece are provided with swastika-shaped contact through grooves.

As an optional form of the vacuum interrupter with triggered cathodes, both the first transverse magnetic field contact piece and the second transverse magnetic field contact piece are provided with Archimedean spiral contact slots.

A vacuum circuit breaker device, including any one of the above-mentioned technical means with a vacuum interrupter that triggers the cathode.

Compared with prior art, effect of the present invention: In the vacuum interrupter with a trigger cathode provided by the present invention, the first transverse magnetic field contact piece is installed on the static conductive rod, and the first trigger cathode is arranged on the arcing surface of the first transverse magnetic field contact piece. The second transverse magnetic field contact piece is installed on the movable conductive rod, and the second trigger cathode is set on the arcing surface of the second transverse magnetic field contact piece, and the first trigger cathode and the second trigger cathode are set in one-to-one correspondence, that is, in the closing During the gate process, the moving conductive rod moves to a set distance from the static conductive rod, and the strong electric field in the gap between the second transverse magnetic field contact piece and the first transverse magnetic field contact piece causes the first trigger cathode and the second trigger cathode to release a large amount of field Electrons are emitted, resulting in the breakdown of the contact gap, and the distance of the contact gap remains unchanged every time a pre-breakdown occurs, which significantly improves the stability of the opening distance of the vacuum interrupter contact pre-breakdown gap; moreover, the contact gap The vacuum arc that appears after being broken down will move on the surface of the contact under the drive of the transverse magnetic field generated by the transverse magnetic field contact piece, so as to avoid excessive ablation of the trigger cathode by the vacuum arc and ensure a high electrical life of the trigger cathode , which improves the electrical performance of the vacuum interrupter when it is used as a closing trigger switch.

The vacuum circuit breaker device provided by the present invention adopts the above-mentioned vacuum interrupter as the closing switch, and the distance between the contact gaps remains unchanged every time the pre-breakdown occurs, which significantly improves the pre-breakdown contact of the vacuum interrupter. Gap distance stability.

The technical means in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. The components of the embodiments of the invention generally described and shown in the drawings herein may be arranged and designed in a variety of different configurations.

It should be noted that similar symbols and letters denote similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

In the description of the present invention, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate directions or The positional relationship is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship that is usually placed when the product of the invention is used. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying the referred device Or elements must have a particular orientation, be constructed and operate in a particular orientation. In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions, and should not be construed as indicating or implying relative importance. In the description of the present invention, unless otherwise stated, "plurality" means two or more.

In the description of the present invention, it should also be noted that, unless otherwise specified and limited, the terms "setting" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection, or Connected integrally; either mechanically or electrically. Those with ordinary knowledge in the technical field can understand the specific meanings of the above terms in the present invention in specific situations.

In the present invention, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may include direct contact between the first and second features, and may also include the first and second features Not in direct contact but through another characteristic contact between them. Moreover, "above", "above" and "above" the first feature on the second feature include that the first feature is directly above and obliquely above the second feature, or simply means that the level of the first feature is higher than that of the second feature. "Below", "below" and "under" the first feature on the second feature include that the first feature is directly below and obliquely below the second feature, or simply means that the first feature is less horizontally than the second feature.

Embodiments of the present invention are described in detail below, examples of which are shown in the drawings, wherein the same or similar symbols denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary only for explaining the present invention.

In order to improve the stability of the pre-breakdown gap opening distance of the closing contact gap of the vacuum interrupter when the vacuum interrupter is used as the closing trigger switch, this embodiment provides a vacuum interrupter, and the following is combined with Figures 1 to 8 The specific content of this embodiment will be described in detail. [Example] Example one

As shown in Figure 1, the vacuum interrupter includes a static conduction rod 1, a moving conduction rod 2 and an electrode structure 3, the electrode structure 3 includes a first electrode 31 and a second electrode 32, and the static conduction rod 1 is close to one side of the moving conduction rod 2. A first electrode 31 is provided on the end surface, and a second electrode 32 is provided on an end surface of the moving conductive rod 2 close to the static conductive rod 1;

Wherein, the first electrode 31 includes a first trigger cathode 311 and a first transverse magnetic field contact piece 312, the first transverse magnetic field contact piece 312 is arranged on the static conductive rod 1, and the first trigger cathode 311 is arranged on the first transverse magnetic field contact piece. The arcing surface of sheet 312. The second electrode 32 includes a second trigger cathode 321 and a second transverse magnetic field contact piece 322, the second transverse magnetic field contact piece 322 is arranged on the moving conductive rod 2, and the second trigger cathode 321 is arranged on the second transverse magnetic field contact piece 322 arcing surface. The first trigger cathodes 311 and the second trigger cathodes 321 are provided in one-to-one correspondence.

In short, in the vacuum interrupter provided by the present invention, the first transverse magnetic field contact piece 312 is installed on the static conductive rod 1, and the first trigger cathode is arranged on the arcing surface of the first transverse magnetic field contact piece 312 311, install the second transverse magnetic field contact piece 322 on the moving conductive rod 2, and set the second trigger cathode 321 on the arcing surface of the second transverse magnetic field contact piece 322, the first trigger cathode 311 and the second trigger cathode 321 are set in one-to-one correspondence, that is, during the closing process, the moving conductive rod 2 moves to a set distance from the static conductive rod 1, and the strong electric field in the gap between the second transverse magnetic field contact piece 322 and the first transverse magnetic field contact piece 312 makes The first trigger cathode 311 and the second trigger cathode 321 release a large number of field emission electrons, resulting in the breakdown of the contact gap, and the distance between the contact gap remains unchanged every time a pre-breakdown occurs, which significantly improves the contact performance of the vacuum interrupter. The stability of the opening distance of the pre-breakdown gap; moreover, the vacuum arc that appears after the contact gap is broken down will be driven by the transverse magnetic field generated by the transverse magnetic field contact piece, and move on the contact surface to avoid the vacuum arc on the trigger The excessive ablation of the cathode ensures that the trigger cathode has a high electrical life, and improves the electrical performance of the vacuum interrupter when it is used as a closing trigger switch.

The vacuum interrupter of this embodiment consists of an airtight insulating shell made of glass or ceramics, a moving end cover, a fixed end cover and a stainless steel bellows 4 to form an airtight insulating system. In order to ensure good airtightness between glass, ceramics and metal, in addition to strict operating procedures when sealing, it is also required that the air permeability of the material itself is as small as possible and the internal gas release is limited to a minimum value. The role of the stainless steel bellows 4 can not only isolate the vacuum state inside the vacuum interrupter from the external atmospheric state, but also enable the moving contact and the moving conductive rod 2 to move within a specified range to complete the closing of the vacuum switch and breaking operation.

The materials of the first trigger cathode 311 and the second trigger cathode 321 in this embodiment are cathode materials such as metal molybdenum or metal titanium. The materials of the second transverse magnetic field contact piece 322 and the first transverse magnetic field contact piece 312 can be copper chromium or copper tungsten alloys to make contact materials.

In one embodiment, as shown in FIG. 1 and FIG. 6 , the first trigger cathode 311 and the second trigger cathode 321 are ring-shaped structures, and are coaxially arranged with the static conductive rod 1 and the dynamic conductive rod 2 .

In one embodiment, the first trigger cathode 311 is recessed with a first annular discharge groove 313, and the second trigger cathode 321 is recessed with a second annular discharge groove 323. The first annular discharge groove 313 and The second annular discharge grooves 323 are provided in one-to-one correspondence. The first annular discharge groove 313 and the second annular discharge groove 323 are arranged opposite to each other, so as to facilitate the release of electrons and promote the pre-breakdown.

In one embodiment, as shown in FIG. 7 , the longitudinal sections of the first annular discharge groove 313 and the second annular discharge groove 323 are both rectangular. Expand the emission area of the electrons that trigger the release of the cathode to ensure the pre-breakdown effect.

In one embodiment, as shown in FIG. 2 , the arcing surface of the first transverse magnetic field contact piece 312 is recessed with a first installation groove 314 , and the first trigger cathode 311 is fixed in the first installation groove 314 by soldering. Ensure that the first trigger cathode 311 is firmly installed in the first installation groove 314 . Furthermore, the arcing surface of the second transverse magnetic field contact piece 322 is recessed with a second installation groove 324 , and the second trigger cathode 321 is fixed in the second installation groove 324 by soldering. Ensure that the second trigger cathode 321 is firmly installed in the second installation groove 324 .

In the related art, the vacuum circuit breaker controls the vacuum arc mainly through the magnetic field generated by the contact structure during the current breaking process. According to the direction of the magnetic field, it is mainly divided into a transverse magnetic field contact structure and a longitudinal magnetic field contact structure, these two main types of magnetic field action. Among them, the transverse magnetic field contact structure mainly uses the slotted structure of the contact to control the flow path of the current, so as to generate a transverse magnetic field parallel to and tangent to the contact surface to drive the arc to move on the contact surface. Under the action of the transverse magnetic field, the ablation of the contacts can be greatly reduced, and under the action of the transverse magnetic field, the vacuum arc has a higher arc voltage.

In one embodiment, as shown in FIG. 2 and FIG. 4 , both the first transverse magnetic field contact piece 312 and the second transverse magnetic field contact piece 322 are provided with swastika-shaped contact through grooves 5 .

As shown in Figures 4 and 5, the second transverse magnetic field contact piece 322 is provided with a second connection hole 325, and the movable conductive rod 2 is inserted into the second connection hole 325 to ensure that the second transverse magnetic field contact piece 322 is connected to the second connection hole 325. The movable conducting rod 2 is assembled stably and firmly.

As shown in Figures 2 and 3, the first transverse magnetic field contact piece 312 is provided with a first connection hole 315, and the static conductive rod 1 is inserted into the first connection hole 315 to ensure that the first transverse magnetic field contact piece 312 is connected to the first connection hole 315. The static conductive rod 1 is assembled stably and firmly.

This embodiment also provides a vacuum circuit breaker device, which includes the above-mentioned vacuum interrupter with a trigger cathode. [Example] Example two

This embodiment provides a vacuum interrupter. Compared with Embodiment 1, the basic structure of the vacuum interrupter provided by this embodiment is the same as that of Embodiment 1. There are only differences in the arrangement of the annular discharge groove and the contact through groove. This embodiment The embodiment does not repeat the same structure as that of the first embodiment.

As shown in Figure 8, in one embodiment, the longitudinal sections of the first annular discharge groove 313 and the second annular discharge groove 323 are circular arc-shaped, which is conducive to expanding the electron discharge capacity of the first trigger cathode and the second trigger cathode. radiation area.

In one embodiment, the first transverse magnetic field contact piece 312 and the second transverse magnetic field contact piece 322 may be provided with an Archimedean spiral contact slot.

1: Static conductive rod 2: Moving conduction rod 3: Electrode structure 31: The first electrode 311: The first trigger cathode 312: the first transverse magnetic field contact piece 313: the first annular discharge groove 314: The first installation slot 315: the first connection hole 32: Second electrode 321: the second trigger cathode 322: the second transverse magnetic field contact piece 323: the second annular discharge groove 324: the second installation slot 325: the second connection hole 4: Stainless steel bellows 5: Swastika-shaped contact slot

[Fig. 1] A schematic diagram of the assembly of the vacuum interrupter with a triggered cathode in Embodiment 1 of the present invention. [FIG. 2] A top view of the first transverse magnetic field contact piece in Embodiment 1 of the present invention. [Fig. 3] Schematic diagram of the structure of the static conduction rod in the first embodiment of the present invention. [FIG. 4] A top view of the second transverse magnetic field contact piece in Embodiment 1 of the present invention. [Fig. 5] Schematic diagram of the structure of the moving conductive rod in Embodiment 1 of the present invention. [FIG. 6] A top view of the first trigger cathode in Embodiment 1 of the present invention. [FIG. 7] A sectional view of the first annular discharge groove in Embodiment 1 of the present invention. [FIG. 8] A sectional view of the first annular discharge groove in Embodiment 2 of the present invention.

1: Static conductive rod 2: Moving conduction rod 3: Electrode structure 31: The first electrode 311: The first trigger cathode 312: the first transverse magnetic field contact piece 32: Second electrode 321: the second trigger cathode 322: the second transverse magnetic field contact piece 4: Stainless steel bellows

Claims (10)

A vacuum interrupter with a trigger cathode, comprising a static conducting rod (1) and a moving conducting rod (2), characterized by further comprising: an electrode structure (3), including a first electrode (31) and a second electrode (32), the static conductive rod (1) is provided with the first electrode (31) near an end surface of the dynamic conductive rod (2), and the dynamic conductive rod (2) is close to an end face of the static conductive rod (1) The second electrode (32) is provided; the first electrode (31) includes a first trigger cathode (311) and a first transverse magnetic field contact piece (312), and the first transverse magnetic field contact piece (312) is arranged on The static conductive rod (1), the first trigger cathode (311) is arranged on the arcing surface of the first transverse magnetic field contact piece (312); the second electrode (32) includes a second trigger cathode (321) and The second transverse magnetic field contact piece (322), the second transverse magnetic field contact piece (322) is arranged on the moving conductive rod (2), and the second trigger cathode (321) is arranged on the second transverse magnetic field contact piece The arcing surface of (322); the first trigger cathode (311) and the second trigger cathode (321) are provided in one-to-one correspondence. The vacuum interrupter with a trigger cathode as described in Claim 1, wherein, it is characterized in that the first trigger cathode (311) and the second trigger cathode (321) are both ring-shaped structures, and are connected to the The static conducting rod (1) and the moving conducting rod (2) are coaxially arranged. The vacuum interrupter with a trigger cathode as described in claim 2, wherein, the first trigger cathode (311) is recessed with a first annular discharge groove (313), and the second trigger cathode (321) is concavely provided with a second annular discharge groove (323), and the first annular discharge groove (313) is provided in one-to-one correspondence with the second annular discharge groove (323). The vacuum interrupter with a triggered cathode as described in claim 3, wherein, the longitudinal sections of the first annular discharge groove (313) and the second annular discharge groove (323) are rectangular shape. The vacuum interrupter with a triggered cathode as described in claim 3, wherein, the longitudinal sections of the first annular discharge groove (313) and the second annular discharge groove (323) are both circular arcs shape. The vacuum interrupter with a triggered cathode as described in Claim 1, wherein, it is characterized in that the arcing surface of the first transverse magnetic field contact piece (312) is concavely provided with a first installation groove (314), the The first trigger cathode (311) is fixed in the first installation groove (314) by soldering. The vacuum interrupter with a triggered cathode as described in claim 1, wherein, it is characterized in that the arcing surface of the second transverse magnetic field contact piece (322) is concavely provided with a second installation groove (324), the The second trigger cathode (321) is fixed in the second installation groove (324) by soldering. The vacuum interrupter with a triggered cathode as described in any one of Claims 1 to 7, wherein, it is characterized in that the first transverse magnetic field contact piece (312) and the second transverse magnetic field contact piece ( 322) are all provided with swastika-shaped contact slot (5). The vacuum interrupter with a triggered cathode as described in any one of Claims 1 to 7, wherein, it is characterized in that the first transverse magnetic field contact piece (312) and the second transverse magnetic field contact piece ( 322) are all provided with the contact groove of Archimedes spiral type. A vacuum circuit breaker device, characterized in that the vacuum circuit breaker device includes a vacuum interrupter with a trigger cathode as described in any one of Claims 1 to 9.

Images