CN111463061A - Vacuum arc-extinguishing chamber and vacuum circuit breaker - Google Patents

Abstract

The invention provides a vacuum interrupter and a vacuum circuit breaker to solve the technical problem that the vacuum interrupter in the prior art cannot meet the application requirements of high-power occasions. The vacuum interrupter of the present invention includes a housing, a moving contact and a static contact, the moving contact includes a moving main contact and a moving arc contact, the static contact includes a static main contact and a static arc contact, and the moving main contact There is an arc separation gap between the head and the moving arc contact, and an arc separation gap is set between the static main contact and the static arc contact. The static main contact has a channel extending along the insertion direction. The static main contact and the arc contact The positions of the arc contacts correspond to the moving main contacts and the arc contacts. The static arc contacts are movably assembled on the static main contacts. The static arc contacts extend outside the static main contacts and the moving arc contacts extend outside the moving main contacts. When the switch is closed, the moving arc contact and the static arc contact come into contact with the moving main contact and the static main contact before the moving main contact. The main contacts are separated, and both the moving arc contacts and the static arc contacts are coil magnetic field contacts.

Description

Vacuum interrupters and vacuum circuit breakers

technical field

The invention relates to the fields of vacuum interrupters and vacuum circuit breakers.

Background technique

High-voltage circuit breakers are the most important control and protection equipment in power systems. At present, almost all circuit breakers of 72.5kV and above used in power systems are SF ₆ circuit breakers. However, SF ₆ gas is the strongest greenhouse effect gas restricted by international conventions. The development of vacuum switchgear to replace SF ₆ circuit breakers has become a Research hotspots in the field of high-voltage switches at home and abroad. Compared with SF ₆ circuit breakers, vacuum circuit breakers have the characteristics of environmental friendliness, long service life and maintenance-free. Many institutions at home and abroad have successively developed 72.5kV and 126kV single-break vacuum circuit breakers and run them on the grid. However, the rated current of the existing 126kV single-break vacuum circuit breaker can only reach the rated breaking current of 40kA and the rated current of 2500A, which cannot meet the power system requirements of 126kV/40kA/3150A.

The Chinese utility model patent with the announcement number CN202307674U discloses a vacuum interrupter and a vacuum circuit breaker using the vacuum interrupter, which mainly includes an upper main contact, an upper arc contact, a lower main contact, and a lower arc contact , wherein the upper arc contact and the lower arc contact are located in the middle of the upper main contact and the lower main contact. When the above vacuum circuit breaker is closed or opened, the arc burns on the upper arc contact and the lower arc contact. The upper arc contact and the lower arc contact are made of anti-welding contact materials, so that the upper and lower arc contacts The contacts are capable of withstanding arcing. However, the anti-welding performance of the upper and lower arc contacts is limited by the material of the arc contacts and cannot be applied to higher power occasions.

In the prior art, there are also vacuum arc extinguishing chambers that use coil magnetic field contacts (longitudinal magnetic field contacts and transverse magnetic field contacts) to extinguish arcs, but such contacts currently need to meet both arc extinguishing requirements and current flow requirements. , and the improvement of the arc-extinguishing ability will be accompanied by the increase of the number of turns of the arc-extinguishing coil and the increase of the resistance, that is, the arc-extinguishing ability and the flow-through ability of the magnetic field contact are a pair of contradictions, which are also not suitable for high-power occasion.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a vacuum interrupter to solve the technical problem that the vacuum interrupter in the prior art cannot meet the requirements of high-power applications; the present invention also provides a vacuum circuit breaker, which solves the problem of the existing vacuum interrupter. Technical problems with low rated power.

To achieve the above purpose, the vacuum interrupter of the present invention adopts the following technical solutions:

The vacuum interrupter includes a housing, a moving contact and a static contact, the moving contact includes a moving main contact and a moving arc contact, the static contact includes a static main contact and a static arc contact, and the moving contact includes a static main contact and a static arc contact. There is an arc gap between the main contact and the moving arc contact, and there is an arc gap between the static main contact and the static arc contact. The dynamic and static main contacts are used for normal flow, and the dynamic and static The arc contact is used for arc extinguishing. The static main contact has a channel extending along the insertion direction. The static arc contact is located at one end of the channel close to the static contact. Correspondingly, the static arc contact is movably assembled on the static main contact, the static arc contact extends outside the static main contact and the moving arc contact extends outside the moving main contact so that when the switch is closed, the moving arc The contact and the static arc contact are in contact with the moving main contact and the static main contact before the moving main contact. When the switch is opened, the moving arc contact and the static arc contact are separated after the moving main contact and the static main contact. Both arc contacts and static arc contacts are coil magnetic field contacts.

In the vacuum interrupter of the present invention, the moving arc contacts and the static arc contacts are set as coil magnetic field contacts, and are equipped with special moving and static main contacts, so that the communication between the moving and static main contacts can be fully utilized. Therefore, it is not necessary to consider the flow capacity of the dynamic and static arc contacts, and give full play to its arc-extinguishing characteristics, so that the arc-extinguishing chamber can meet the application requirements of higher power occasions.

Further, in order to avoid forming a pressure cylinder at the end of the static arc contact away from the moving contact, and to facilitate the movement of the static arc contact relative to the static main contact, the channel on the static main contact is a transparent channel, and the static arc contact The head is connected with the static main contact through the static end bellows, and the static end bellows isolates the passage from the outside at the end of the static arc contact away from the moving contact.

Further, compared with the transverse magnetic field contact, the longitudinal magnetic field contact is easier to realize the arc extinguishing ability in a small size. The transverse magnetic field contact can also meet the arc extinguishing requirements, and the dynamic and static arc contacts are longitudinal magnetic field contacts. , or the dynamic and static arc contacts are transverse magnetic field contacts.

Further, in order to limit the arcing position outside the moving main contact and avoid ablation of the moving main contact, the moving main contact is in the shape of a cylinder with one end open, and is sleeved on the moving arc contact, with the opening facing the In the static contact, one end of the moving arc contact close to the static contact protrudes beyond the moving main contact.

To achieve the above purpose, the vacuum circuit breaker of the present invention adopts the following technical solutions:

A vacuum circuit breaker includes an operating mechanism and a vacuum arc extinguishing chamber. The vacuum arc extinguishing chamber includes a housing, a static contact and a moving contact that is drive-connected to the operating mechanism. The moving contact includes a moving main contact and a moving arc. The contact, the static contact includes a static main contact and a static arc contact, an arc separation gap is arranged between the moving main contact and the moving arc contact, and an arc gap is arranged between the static main contact and the static arc contact There is an arc gap, the moving and static main contacts are used for normal flow, the moving and static arc contacts are used for arc extinguishing, the static main contact has a channel extending along the insertion direction, and the static arc contact is located close to the channel. At one end of the static contact, the positions of the static main and arc contacts correspond to the moving main and arc contacts, the static arc contacts are movably assembled on the static main contacts, and the static arc contacts extend beyond the static main contacts and the dynamic contacts. The arc contact extends beyond the moving main contact so that when closing, the moving arc contact and the static arc contact are in contact with the moving main contact and the static main contact before the moving main contact. The static arc contact is separated from the moving main contact and the static main contact, and both the moving arc contact and the static arc contact are coil magnetic field contacts.

In the vacuum circuit breaker of the present invention, the moving arc contacts and the static arc contacts are set as coil magnetic field contacts, and are equipped with special moving and static main contacts, so that the flow of the moving and static main contacts can be fully utilized It is no longer necessary to consider the current flow capacity of the dynamic and static arc contacts, and give full play to its arc extinguishing characteristics, so that the circuit breaker can meet the application requirements of higher power occasions.

Further, in order to avoid forming a pressure cylinder at the end of the static arc contact away from the moving contact, and to facilitate the movement of the static arc contact relative to the static main contact, the channel on the static main contact is a transparent channel, and the static arc contact The head is connected with the static main contact through the static end bellows, and the static end bellows isolates the passage from the outside at the end of the static arc contact away from the moving contact.

Further, compared with the transverse magnetic field contact, the longitudinal magnetic field contact is easier to realize the arc extinguishing ability in a small size. The transverse magnetic field contact can also meet the arc extinguishing requirements, and the dynamic and static arc contacts are longitudinal magnetic field contacts. , or the dynamic and static arc contacts are transverse magnetic field contacts.

Further, in order to limit the arcing position outside the moving main contact and avoid ablation of the moving main contact, the moving main contact is in the shape of a cylinder with one end open, and is sleeved on the moving arc contact, with the opening facing the In the static contact, one end of the moving arc contact close to the static contact protrudes beyond the moving main contact.

Description of drawings

FIG. 1 is a schematic diagram of the vacuum interrupter of Embodiment 1 of the vacuum circuit breaker of the present invention.

In the figure: 1. Static bellows; 2. Static conductive rod; 3. Static main contact; 4. Main shield; 5. Static longitudinal magnetic field contact; 51. Conductive rod; 6. Dynamic longitudinal magnetic field contact; 7 , moving main contact; 8, moving conductive rod; 9, shell; 10, moving bellows; 11, main contact pressure spring.

Detailed ways

The specific embodiments of the present invention will be further described below with reference to the accompanying drawings.

The specific embodiment 1 of the vacuum circuit breaker of the present invention, as shown in FIG. 1 , includes an operating mechanism (not shown in the figure) and a vacuum interrupter. The vacuum interrupter includes a casing 9 and is assembled in the casing 9 The static contact and the moving contact connected with the operating mechanism. The static contact includes a static main contact 3 and a static arc contact, and the moving contact includes a moving main contact 7 and a moving arc contact. During the arcing process, the arc is transferred from the moving arc contact to the moving main contact 7 to ablate the moving main contact 7; there is an arc gap between the static main contact 3 and the static arc contact to prevent the arcing process , the arc is transferred from the static arc contact to the static main contact 3 to ablate the static main contact 3. Both the static arc contact and the moving arc contact are coil magnetic field contacts. Specifically, in this embodiment, the static arc contact The head is a static longitudinal magnetic field contact 5, and the moving arc contact is a moving longitudinal magnetic field contact 6 (in other embodiments, the moving and static arc contacts may also be transverse magnetic field contacts). Among them, the moving main contact 7 and the static main contact 3 are used for normal conduction and current flow, and the moving longitudinal magnetic field contact 6 and the static longitudinal magnetic field contact 5 are used for arc extinguishing. At the contact position between the static contact and the moving contact, a main shield 4 for shielding the electric field is also provided in the circumferential direction.

The vacuum interrupter also includes a static conductive rod 2 with a cylindrical structure. The static conductive rod 2 is fixedly connected to the upper end surface of the housing 9 , and the lower end of the static conductive rod 2 forms a static main contact 3 . The static conductive rod 2 has a transparent channel extending along the insertion direction, the conductive rod 51 is arranged in the channel, the upper end of the conductive rod 51 is provided with a static bellows 1 , and the static longitudinal magnetic field contact 5 is arranged on the lower end of the conductive rod 51 , the upper end of the static bellows 1 is connected with the static conductive rod 2 , and the channel is isolated from the outside by the upper end of the static bellows 1 . When the static longitudinal magnetic field contact 5 is in contact with the dynamic longitudinal magnetic field contact 6 and is subjected to upward pressure, the static longitudinal magnetic field contact 5 can move up and down relative to the static conductive bar 2 . The static longitudinal magnetic field contact 5 extends beyond the static main contact 3 along the length direction of the conductive rod 51 . The upper ends of the static conductive rod 2 and the static bellows 1 are fixedly connected to the upper wiring board (not shown in the figure) of the circuit breaker.

The vacuum interrupter also includes a movable conductive rod 8 , and the movable conductive rod 8 is assembled in the casing 9 and can move up and down relative to the casing 9 . The movable conductive rod 8 is in contact with the lower wiring board (not shown in the figure) through a sliding conductive method such as a strap contact finger or a spring contact finger, forming a main conductive circuit together. The moving main contact 7 and the moving longitudinal magnetic field contact 6 are arranged on the upper end of the moving conductive rod 8. The moving main contact 7 is in the shape of a cylinder with one end open, the opening faces the static contact, and is sleeved on the moving longitudinal magnetic field contact 6. The longitudinal magnetic field contact 6 is arranged inside the moving main contact 7 . The moving main contact 7 is arranged in the up and down direction corresponding to the static main contact 3, the moving longitudinal magnetic field contact 6 is arranged in the up and down direction corresponding to the static longitudinal magnetic field contact 5, and the end of the moving longitudinal magnetic field contact 6 close to the static contact protrudes beyond the moving main contact 7. The lower end of the movable conductive rod 8 is also provided with a movable bellows 10 , and the lower end of the movable bellows 10 is further provided with a main contact pressure spring 11 . The main contact pressure spring 11 is in driving connection with an operating mechanism (not shown in the figure), and the operating mechanism is used to drive the moving contact to move toward the stationary contact.

When the vacuum circuit breaker of the present invention is in use, the main contact pressure spring 11 moves to the static contact together with the movable conductive rod 8 and the movable longitudinal magnetic field contact 6 under the action of the mechanism. Since the dynamic longitudinal magnetic field contact 6 protrudes from the moving main contact 7 , and the static longitudinal magnetic field contact 5 protrudes from the static main contact 3 , the dynamic longitudinal magnetic field contact 6 and the static longitudinal magnetic field contact 5 come into contact first. When the dynamic longitudinal magnetic field contact 6 is in contact with the static longitudinal magnetic field contact 5, since the initial pressure of the main contact pressure spring 11 is greater than the final pressure of the elastic elements such as the static bellows 1, the elastic elements such as the static bellows 1 shrink and deform, and the dynamic The longitudinal magnetic field contact 6 pushes the static longitudinal magnetic field contact 5 to move upward. When the moving main contact 7 is in contact with the static main contact 3, the main contact pressure spring 11 is compressed to provide positive pressure for the closing contact between the moving main contact 7 and the static main contact 3, thereby reducing the contact force between the contacts. resistance, so that the rated current passes through, and the closing operation is completed. In the initial stage of opening of the circuit breaker, the main contact pressure spring 11 moves downward to release the pressure on the moving main contact 7 . After the moving main contact 7 is separated from the static main contact 3, the moving longitudinal magnetic field contact 6 and the static longitudinal magnetic field contact 5 are still in a closed state under the action of the elastic element. The moving conductive rod 8 continues to move downward. When the elastic elements such as the static bellows 1 return to their original state, the moving longitudinal magnetic field contact 6 is separated from the static longitudinal magnetic field contact 5, and an arc is generated therebetween. Due to the action of the longitudinal magnetic field between the dynamic longitudinal magnetic field contact 6 and the static longitudinal magnetic field contact 5, the arc is well controlled between the dynamic longitudinal magnetic field contact 6 and the static longitudinal magnetic field contact 5, avoiding the moving main contact 7 and the static main contact 3 are subject to arc ablation, thereby ensuring the smooth breaking of the circuit breaker.

The difference between the other embodiments of the vacuum circuit breaker of the present invention and the first embodiment is that the channel on the static main contact need not be transparent. In this case, the static bellows can be omitted.

The specific embodiment of the vacuum interrupter of the present invention has the same structure as the vacuum interrupter in the above-mentioned embodiment of the vacuum circuit breaker, and will not be described again.

Claims (8)

1. The vacuum interrupter includes a housing, a moving contact and a static contact. The moving contact includes a moving main contact and a moving arc contact, and the static contact includes a static main contact and a static arc contact. An arc separation gap is arranged between the moving main contact and the moving arc contact, and an arc separation gap is arranged between the static main contact and the static arc contact. The moving and static main contacts are used for normal flow, and the moving , The static arc contact is used for arc extinguishing. The static main contact has a channel extending along the insertion direction. The static arc contact is located at one end of the channel close to the static contact. The positions of the static main and arc contacts are related to the moving main, Corresponding to the arc contacts, the static arc contacts are movably assembled on the static main contacts, the static arc contacts extend outside the static main contacts and the moving arc contacts extend outside the moving main contacts so that when the switch is closed, The moving arc contact and the static arc contact come into contact with the static main contact before the moving main contact. When the switch is opened, the moving arc contact and the static arc contact separate from the moving main contact and the static main contact. It is characterized in that: both the moving arc contacts and the static arc contacts are coil magnetic field contacts. 2. The vacuum interrupter according to claim 1, wherein the channel on the static main contact is a transparent channel, the static arc contact is connected with the static main contact through the static end bellows, and the static end corrugated The tube isolates the channel from the outside world at the end of the static arcing contact facing away from the moving contact. 3. The vacuum interrupter according to claim 1 or 2, wherein the dynamic and static arc contacts are longitudinal magnetic field contacts, or the dynamic and static arc contacts are transverse magnetic field contacts. 4. The vacuum interrupter according to claim 1 or 2, wherein the moving main contact is in the shape of a cylinder with one end open, and is sleeved on the moving arc contact, with the opening facing the static contact , the end of the moving arc contact close to the static contact protrudes beyond the moving main contact. 5. A vacuum circuit breaker, including an operating mechanism and a vacuum interrupter, the vacuum interrupter includes a housing, a static contact, and a moving contact that is drive-connected to the operating mechanism, and the moving contact includes a moving main contact and a A moving arc contact, the static contact includes a static main contact and a static arc contact, an arc separation gap is arranged between the moving main contact and the moving arc contact, and the gap between the static main contact and the static arc contact is There is an arc separation gap. The moving and static main contacts are used for normal flow, and the moving and static arc contacts are used for arc extinguishing. The static main contact has a channel extending along the insertion direction, and the static arc contact is located in the channel. The position of the static main and arc contacts corresponds to the moving main and arc contacts. The static arc contacts are movably assembled on the static main contacts, and the static arc contacts extend beyond the static main contacts. And the moving arc contact extends beyond the moving main contact so that when closing, the moving arc contact and the static arc contact are in contact with the moving main contact and the static main contact before the moving main contact. The head and the static arc contact are separated after the moving main contact and the static main contact. The characteristic is that the moving arc contact and the static arc contact are both coil magnetic field contacts. 6. The vacuum circuit breaker according to claim 5, wherein the channel on the static main contact is a transparent channel, the static arc contact is connected to the static main contact through a static end bellows, and the static end bellows is connected to the static main contact. The channel is isolated from the outside at the end of the static arcing contact facing away from the moving contact. 7. The vacuum circuit breaker according to claim 5 or 6, wherein the dynamic and static arc contacts are longitudinal magnetic field contacts, or the dynamic and static arc contacts are transverse magnetic field contacts. 8. The vacuum circuit breaker according to claim 5 or 6, wherein the moving main contact is in the shape of a cylinder with one end open, and is sleeved on the moving arc contact, and the opening faces the static contact, One end of the moving arc contact close to the stationary contact protrudes beyond the moving main contact.

Images