JP3298360B2 - Puffer type gas circuit breaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

This invention relates to an arc-extinguishing gas,
The present invention relates to a gas circuit breaker for electric power in which F ₆ is used, and more particularly to a circuit breaker which is compact because a magnetic field is formed in an opening gap of an arc contact.

[0002]

2. Description of the Related Art A puffer type gas circuit breaker compresses an arc-extinguishing gas and blows the compressed gas to an opening gap of an arc contact to extinguish an arc and interrupt a current.
SF ₆ gas is very excellent as an arc-extinguishing gas for this circuit breaker, and is widely used for circuit breakers of medium to small capacity to large capacity.

FIG. 9 is a sectional view showing the structure of a conventional puffer type gas circuit breaker. A fixed arc contact 1 made of a shaft-shaped conductor is fixed to a metal base 8. This pedestal 8
Is fixed to the closed tank 9 via an insulating support (not shown). The pedestal 8 fixes the fixed main contact 6 provided with the contact conductor 6 </ b> A and supports the upper end of the insulating cylinder 12. Another pedestal 13 supports the lower end of the insulating cylinder 12. The pedestal 13 is also fixed to the closed tank 9 via another insulating support (not shown), like the pedestal 8. Further, the pedestal 13 fixes the current-carrying contact 11 provided with the contact conductor 11A.

In FIG. 9, a movable arc contact 2 is fixed to an upper end of a metallic movable cylinder 4, and a drive rod 14 is attached to the lower end of the movable cylinder 4.
The drive rod 14 is connected to a drive device (not shown), and can drive the drive rod 14 in the X direction or the anti-X direction. The movable cylinder 4 and the puffer cylinder 3 are integrated, and a second insulating nozzle 7B is fixed to the upper end surface.

Further, in FIG. 9, the puffer cylinder 3 forms a thermal puffer chamber 3B and also forms a main puffer chamber 3A with the movable cylinder 4. A fixed piston 10 is disposed in the main puffer chamber 3A, and the fixed piston 10 is fixed to the pedestal 13 side. The first insulating nozzle 7A is fixed to the upper end surface of the puffer cylinder 3, and the movable main contact 5 is attached.
The sealed tank 9 is filled with SF ₆ gas,
The pedestals 8 and 13 are connected to other internal devices (not shown) in the closed tank 9 and main circuit conductors.

In the gas circuit breaker shown in FIG. 9, a drive rod 14, a movable cylinder 4, a puffer cylinder 3, a movable arc contact 2, a first insulating nozzle 7A, a second insulating nozzle 7B, and a movable main contact 5 are all integrated from the bottom. The contact is opened and closed by moving in the axial direction. At this time, the main fixed contact 6 and the main movable contact 5 slide with each other, and the fixed arc contact 1 and the movable arc contact 2 slide with each other. The former main contact is intended for energization,
The latter arc contact is for extinguishing the arc generated at the time of breaking.

FIG. 10 is an enlarged sectional view of a main part of FIG.
The movable arc contact 2 is formed of a hollow conductor 2B, and has a contact conductor 2A on an upper portion. Next, returning to FIG. 9, a mechanism when the gas circuit breaker is shut off will be described. FIG. 9 shows a state in which the main circuit is being cut off. The operation state of the device is determined by the movable parts (main movable contact 5 and movable arc contact 2).
9) is located at a position higher than the state of FIG. 9, and the fixed arc contact 1 is inserted into the lumen 2C of the movable arc contact 2 made of a hollow conductor. At this time, the main movable contact 5 is also fitted into the hollow portion 6C of the main fixed contact 6. Further, the puffer cylinder 3 is also fitted into the energizing contact 11. The contact conductors 2A (FIG. 10), 6A, and 11A are composed of conductors divided into a plurality in the circumferential direction, and are configured to constantly press a partner conductor that passes therethrough by a ring-shaped spring (not shown). The contact resistance during energization is reduced. The contact conductor 6A connects the fixed main contact 6 and the movable main contact 5,
The contact conductor 11A is for bringing the energizing contact 11 into contact with the puffer cylinder 3, and the contact conductor 2A (FIG. 10) is for bringing the fixed arc contact 1 and the hollow conductor 2B of the movable arc contact 2 into good contact with each other. In the closed state, the main circuit current flowing through the device flows from the energizing contact 11 to the fixed main contact 6 via the movable main contact 5 and from the energizing contact 11 to the fixed arc contact 1 via the movable arc contact 2. In FIG. 9, when the movable portion (movable arc contact 2 or the like) starts to move in the X direction from the closed state, first, the fixed main contact 6 and the movable main contact 5 are separated. In this state, the fixed arc contact 1 and the movable arc contact 2 are in contact. Therefore, since all the main circuit current flows to the arc contact side, no arc is generated at the main contact side. Further, when the movable part moves in the X direction, the fixed arc contact 1 and the movable arc contact 2 begin to separate. This state corresponds to FIGS. 9 and 10. At this time, an arc 17 is formed in the gap 16 between the arc contacts as shown in FIG.

The arc 17 is cooled by blowing compressed gas stored in the main puffer chamber 3A and the heat puffer chamber 3B. This compressed gas is the amount that was compressed by the fixed piston 10 when the puffer cylinder 3 moved in the X direction. The first insulating nozzle 7A and the second insulating nozzle 7B are guides for effectively blowing the compressed gas to the arc 17, and when the fixed arc contact 1 comes out of the first insulating nozzle 7A, a large amount of the compressed gas is blown out. The arc 17 is extinguished. In this device, an arc is generated only between a fixed arc contact 1 and a movable arc contact 2. For this purpose, each fixed and movable contact is given the name "arc". Although not shown, the fixed arc contact 1 and the movable arc contact 2 are fitted with an arc-resistant metal at a portion directly exposed to the arc 17.

[0009]

However, the conventional apparatus as described above has been required to have a more compact physique. That is, it is always demanded from the economic point of view to make the physique more compact without changing the breaking capacity of the device. This device can increase the breaking capacity, but, of course, increasing the breaking capacity leads to an increase in the amount of compressed gas, an increase in the size of the puffer cylinder, an increase in the size of the driving device, and a reduction in cost. Also rises.

An object of the present invention is to make it possible to reduce the required amount of compressed gas and the size of a puffer chamber, and to make the size of the apparatus more compact.

[0011]

According to the present invention, there is provided, in accordance with the present invention, a fixed arc contact made of a shaft-like conductor and a fixed arc contact formed of a shaft-like conductor in a tank filled with an arc-extinguishing gas. A movable arc contact that is movable in the axial direction and moves in and out of the fixed arc contact by moving the fixed arc contact into and out of the lumen of the hollow conductor is disposed, and is generated in an opening gap between the fixed arc contact and the movable arc contact. In a gas circuit breaker in which an arc is blown out by a compressed gas, a portion of a fixed arc contact on a movable arc contact side becomes a spiral conductor formed spirally along the axial direction, and the spiral conductor is formed. A gap is provided between the conductors adjacent in the axial direction.

Alternatively, a fixed arc contact made of an axial conductor and a fixed arc contact movable in the axial direction of the fixed arc contact into and out of the hollow conductor of the hollow conductor are placed in a tank filled with an arc-extinguishing gas. In the gas circuit breaker, a movable arc contact which comes into contact with and separates from the fixed arc contact is disposed, and an arc generated in an opening gap between the fixed arc contact and the movable arc contact is blown out by the compressed gas. The part on the fixed arc contact side becomes a spiral conductor formed spirally along the axial direction,
A gap may be provided between the axially adjacent conductors forming the helical conductor.

Alternatively, in such a configuration, the portion of the fixed arc contact on the side of the movable arc contact becomes a second helical conductor spirally formed along the axial direction and forms the second helical conductor. A gap may be formed between the conductors adjacent in the axial direction.

[0014]

According to the structure of the present invention, the fixed arc contact, the movable arc contact, or both the movable arc contact and the fixed arc contact are formed in a spiral shape. When the device attempts to interrupt the current, a current flows through the helical portion of the arc contact, thereby creating a magnetic field in the open gap of the arc contact. In the separation gap, the Lorentz force due to the magnetic field and the current flowing through the arc acts on the arc itself. For this reason, the arc-extinguishing effect in which the arc is forcibly bent and torn off is strongly exerted. In addition, as the breaking current increases, the magnetic field also increases, so that the arc extinguishing ability also increases according to the breaking capacity. Therefore, the required amount of compressed gas can be reduced as compared with the conventional one, and the apparatus can be made compact.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments. FIG. 1 is an enlarged sectional view of a main part of a puffer type gas circuit breaker according to an embodiment of the present invention. A spiral conductor 18A is provided below the shaft-shaped conductor 18B of the fixed arc contact 18 in a spiral shape. Other configurations are
This is the same as the conventional configuration described with reference to FIGS. The same portions are denoted by the same reference numerals, and the detailed description will not be repeated.

FIG. 5 is an enlarged sectional view of a main part showing a magnetic field distribution around the separation gap 16 in FIG. Since the arc contact is being opened, the current I is flowing through the arc 17. On the other hand, since the current I also flows through the spiral conductor 18A, the magnetic flux 21
Are also formed in the separation gap 16. From the current I flowing through the arc 17 and the magnetic field H generated by the magnetic flux 21, the arc 1
Lorentz force acts on 7. As a result, the arc itself is forcibly bent, torn off, and easily extinguished. The arc 17 is not constant in time and the separation gap 1
6 is always moving around. For this reason, the direction of the current I constantly changes, and accordingly, the direction and the value of the Lorentz force also change. However, at any time, the Lorentz force is generated in a direction in which the arc 17 is bent in a lateral direction and is torn off, so that the arc extinguishing action works strongly.

FIG. 2 is an enlarged sectional view of a main part of a puffer circuit breaker according to another embodiment of the present invention. The difference from FIG. 1 is that the fixed arc contact 1 is a conventional shaft-shaped conductor, and that a spiral conductor 19A wound in a spiral shape is provided above the hollow conductor 19B of the movable arc contact 19. . FIG. 6 is an enlarged sectional view of a main part showing a magnetic field distribution around the separation gap 16 in FIG. The magnetic flux 21 crosses the arc 17, and a Lorentz force acts on the arc 17 from the current I flowing through the arc 17 and the magnetic field H. Also in this case, the arc 17 is bent, and the arc-extinguishing function works strongly.

FIG. 3 is an enlarged sectional view of a main part of a puffer type circuit breaker according to still another embodiment of the present invention. FIG.
Axial conductor 18B is also provided on fixed arc contact 18 different from that of
Spiral conductor 18 wound around the lower side of the conductor
A is provided. The spiral conductors 18A and 19A
Are wound in the same direction as each other. FIG. 7 is an enlarged sectional view of a main part showing a magnetic field distribution around the separation gap 16 in FIG. The magnetic flux 21 flows relatively along the axial direction (vertical direction) in the separation gap 16, but the arc 17 moves around in a complicated manner, so that the arc 17 always crosses the magnetic flux 21. Also in this case, the Lorentz force acts on the arc 17 itself from the current I flowing through the arc 17 and the magnetic field H, and a strong arc-extinguishing effect acts on the arc 17.

FIG. 4 is an enlarged sectional view of a main part showing a configuration of a puffer type circuit breaker according to still another embodiment of the present invention. 3 is different from the configuration in FIG. 3 in that a spiral conductor 20A in which the movable arc contact 20 is spirally wound above the hollow conductor 20B is provided, and the spiral conductors 18A and 20A are wound in opposite directions. Only points. FIG.
FIG. 5 is an enlarged sectional view of a main part showing a magnetic field distribution around a separation gap 16 in FIG. 4. Also in this case, the magnetic flux crosses the arc 17,
A Lorentz force acts on the arc 17 itself from the current I flowing through the arc 17 and the magnetic field H, and a strong arc extinguishing action acts on the arc 17.

[0020]

As described above, according to the present invention, a strong arc extinguishing action is applied to the arc in the separation gap by forming the arc contact in a spiral shape. Therefore, the required amount of compressed gas can be reduced, and the apparatus can be made compact. Further, the breaking capacity can be increased without increasing the amount of compressed gas.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a main part showing a configuration of a puffer circuit breaker according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part showing a configuration of a puffer circuit breaker according to another embodiment of the present invention.

FIG. 3 is an enlarged sectional view of a main part showing a configuration of a puffer-type circuit breaker according to still another embodiment of the present invention.

FIG. 4 is an enlarged sectional view of a main part showing a configuration of a puffer circuit breaker according to still another embodiment of the present invention.

FIG. 5 is an enlarged sectional view of a main part showing a magnetic field distribution around the separation gap in FIG. 1;

FIG. 6 is an enlarged sectional view of a main part showing a magnetic field distribution around the separation gap in FIG. 2;

FIG. 7 is an enlarged sectional view of a main part showing a magnetic field distribution around the separation gap in FIG. 3;

FIG. 8 is an enlarged sectional view of a main part showing a magnetic field distribution around the separation gap in FIG. 4;

FIG. 9 is a sectional view showing a configuration of a conventional puffer-type circuit breaker.

FIG. 10 is an enlarged sectional view of a main part of FIG. 9;

[Explanation of symbols]

1, 18: fixed arc contact, 2, 19, 20: movable arc contact, 18A, 19A, 20A: spiral conductor, 18
B: axial conductor, 2B, 19B, 20B: hollow conductor, 1
6: separation gap, 17: arc, 21: magnetic flux

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01H 33/91 H01H 33/12 H01H 33/70

Claims (3)

(57) [Claims] 1. A fixed arc contact made of an axial conductor and a fixed arc contact movable in the axial direction of the fixed arc contact into and out of a hollow of a hollow conductor in a tank filled with an arc-extinguishing gas. A fixed arc contact is provided in the gas circuit breaker in which a fixed arc contact and a movable arc contact which come into contact with and separated from the fixed arc contact are arranged, and an arc generated in an opening gap between the fixed arc contact and the movable arc contact is blown out by the compressed gas. Is formed as a helical conductor spirally formed along the axial direction, and a gap is formed between the axially adjacent conductors forming the helical conductor. A puffer type gas circuit breaker characterized by the above. 2. A fixed arc contact made of a shaft-like conductor and a fixed arc contact movable in the axial direction of the fixed arc contact into and out of a bore of a hollow conductor in a tank filled with an arc-extinguishing gas. In the gas circuit breaker, a movable arc contact which comes into contact with and separates from the fixed arc contact is disposed, and an arc generated in an opening gap between the fixed arc contact and the movable arc contact is blown out by the compressed gas. Is a spiral conductor formed spirally along the axial direction, and a gap is formed between the axially adjacent conductors forming the spiral conductor. A puffer type gas circuit breaker characterized by the above. 3. A second spiral conductor according to claim 2, wherein a portion of the fixed arc contact on the movable arc contact side is a second spiral conductor spirally formed along said axial direction. A puffer type gas circuit breaker, wherein a gap is provided between the axially adjacent conductors forming a helical conductor.