JPH08315696A - Buffer type gas breaker - Google Patents

Abstract

PURPOSE: To improve the erasion capacity by forming the required part of a fixed arc contact into a spiral shape, and generating a magnetic field in the space between the arc contacts. CONSTITUTION: In tank charged with arc-extinguishing gas, arc generated in the space 16 between a movable arc contact 2 and a fixed arc contact 18 is blown off by compressed gas. A spiral conductor 18A is provided on the contact side 2 of this contact 18, and a magnetic field is generated in the space 16 by the current flowing to the conductor 18A, and Lorentz's force works by the magnetic field and the arc current, and the arc is bent forcibly and torn off. Hereby, arc-extinguishing capacity is raised, and the constitution of the puffer type gas breaker can be miniaturized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION This invention relates to S as 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 that is made compact by forming a magnetic field in the opening gap of its 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 onto the opening gap of an arc contact to extinguish the arc and interrupt the current.
SF ₆ gas is extremely excellent as an arc extinguishing gas for this circuit breaker, and is widely used for medium to small capacity to large capacity circuit breakers.

FIG. 9 is a sectional view showing the structure of a conventional puffer type gas circuit breaker. A fixed arc contact 1 made of an axial conductor is fixed to a metallic pedestal 8. This pedestal 8
Are fixed to the closed tank 9 via an insulating support (not shown). The pedestal 8 fixes the fixed main contact 6 having the contact conductor 6A and supports the upper end of the insulating cylinder 12. Another base 13 supports the lower end of the insulating cylinder 12. Similarly to the base 8, the base 13 is also fixed to the closed tank 9 via another insulating support (not shown). Further, the pedestal 13 fixes the energizing contact 11 having the contact conductor 11A.

In FIG. 9, the movable arc contact 2 is fixed to the 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 the 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 a main puffer chamber 3A between itself and the movable cylinder 4. A fixed piston 10 is arranged in the main puffer chamber 3A, and the fixed piston 10 is fixed to the pedestal 13 side. Further, 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 closed tank 9 is filled with SF ₆ gas, and
The pedestals 8 and 13 are connected to other internal devices (not shown) in the closed tank 9 and to the main circuit conductors, respectively.

In the gas circuit breaker of FIG. 9, the drive rod 14, the movable cylinder 4, the puffer cylinder 3, the movable arc contact 2, the first insulating nozzle 7A, the second insulating nozzle 7B, and the movable main contact 5 are all integrated from the bottom. The contact is opened and closed by moving in the axial direction. At that 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 for the purpose of energizing,
The latter arc contact is for extinguishing the arc generated at the time of opening.

FIG. 10 is an enlarged cross-sectional view of the main part of FIG.
The movable arc contact 2 is composed of a hollow conductor 2B, and has a contact conductor 2A on the upper part thereof. Next, returning to FIG. 9, the mechanism when the gas circuit breaker is cut off will be described. FIG. 9 shows a state in which the main circuit is being cut off. When the device is turned on, the moving parts (main moving contact 5 and moving arc contact 2
Etc.) is located above the state of FIG. 9, and the fixed arc contact 1 is in a state of being fitted into the inner cavity 2C of the movable arc contact 2 of the hollow conductor. At that time, the main movable contact 5 is also inserted into the hollow portion 6C of the main fixed contact 6. Further, the puffer cylinder 3 is also fitted in the energizing contact 11. The contact conductors 2A (FIG. 10), 6A, 11A are composed of conductors divided into a plurality in the circumferential direction, and are configured to constantly press the mating conductor penetrating by a ring-shaped spring (not shown), The contact resistance when energized 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 and the puffer cylinder 3 into good contact with each other, and the contact conductor 2A (FIG. 10) is for keeping the fixed arc contact 1 and the hollow conductor 2B of the movable arc contact 2 in good contact with each other. In the closed state, the main circuit current flowing through the device is the amount flowing from the energizing contact 11 to the fixed main contact 6 via the movable main contact 5, and the amount flowing 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 moving 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 with each other. Therefore, since all the main circuit current flows to the arc contact side, no arc is generated on the main contact side. Further, when the movable portion moves in the X direction, the fixed arc contact 1 and the movable arc contact 2 start to separate. This state corresponds to FIGS. 9 and 10, and at that time, an arc 17 is formed in the opening gap 16 of the arc contact as shown in FIG.

The arc 17 is cooled by spraying the compressed gas stored in the main puffer chamber 3A and the hot puffer chamber 3B. The 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 compressed gas blows out. The arc 17 is extinguished. In this device, an arc is generated only between the fixed arc contact 1 and the movable arc contact 2. Therefore, each fixed and movable contact is named "arc". Although not shown, the fixed arc contact 1 and the movable arc contact 2 are fitted with arc-resistant metal at the portions directly exposed to the arc 17.

[0009]

However, the conventional device as described above has been required to have a more compact body. That is, it is always required from the economical viewpoint to make the physique more compact without changing the breaking capacity of the device. This device can increase the breaking capacity, but as a matter of course, if the breaking capacity is increased, the amount of compressed gas increases, the puffer cylinder increases in size, and the drive unit increases in size. Also rises.

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

[0011]

In order to achieve the above object, according to the present invention, a fixed arc contact made of an axial conductor and a fixed arc contact of the fixed arc contact are provided in a tank filled with an arc extinguishing gas. A movable arc contact that is movable in the axial direction and that moves in and out of the hollow conductor by placing the fixed arc contact in and out of contact with the fixed arc contact is placed in the open gap between the fixed arc contact and the movable arc contact. In the gas circuit breaker in which the arc is blown out by the compressed gas, the movable arc contact side of the fixed arc contact is formed in a spiral shape.

Alternatively, in a tank filled with an arc-extinguishing gas, a fixed arc contact made of an axial conductor and movable in the axial direction of the fixed arc contact, and the fixed arc contact is taken in and out from the inner cavity of the hollow conductor. A movable arc contact is provided in which a fixed arc contact and a movable arc contact that comes into contact with and separate from each other are arranged, and the arc generated in the opening gap between the fixed arc contact and the movable arc contact is blown out by compressed gas. The fixed arc contact side may be formed in a spiral shape.

Alternatively, in such a structure, both the fixed arc contact and the movable arc contact may be spirally formed.

[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 seeks to interrupt the current, a current flows through the spiral portion of the arc contact, thus creating a magnetic field in the open gap of the arc contact. In the open gap, the Lorentz force due to this magnetic field and the current flowing through the arc acts on the arc itself. Therefore, the arc extinguishing action, in which the arc is forcibly bent and torn off, works strongly. Moreover, since the magnetic field becomes stronger as the breaking current increases, the arc extinguishing ability also increases according to the breaking capacity. Therefore, the required compressed gas amount can be reduced as compared with the conventional one, and the device can be made compact.

[0015]

EXAMPLES The present invention will be described below based on examples. FIG. 1 is an enlarged sectional view of essential parts 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 in FIGS. 9 and 10. The same portions will be denoted by the same reference symbols and repeated detailed description will be omitted.

FIG. 5 is an enlarged cross-sectional view of an essential part showing the magnetic field distribution around the separation gap 16 shown in FIG. The current I is flowing through the arc 17 because the arc contact is being opened. 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 in the arc 17 and the magnetic field H created by the magnetic flux 21, the arc 1
Lorentz force acts on 7. As a result, the arc itself is forcibly bent, and is easily torn off and easily extinguished. The arc 17 is not constant in time and the opening gap 1
It is constantly moving around in 6. Therefore, the direction of the current I constantly changes, and the direction and value of the Lorentz force also change accordingly. However, at any time, the Lorentz force is generated in the direction in which the arc 17 is bent in the lateral direction and is torn off, so that the arc extinguishing action is strong.

FIG. 2 is an enlarged sectional view of the essential parts of a puffer type 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 axial conductor, and a spirally wound spiral conductor 19A is provided above the hollow conductor 19B of the movable arc contact 19. . FIG. 6 is an enlarged sectional view of an essential part showing the magnetic field distribution around the separation gap 16 of FIG. The magnetic flux 21 intersects the arc 17, and the Lorentz force acts on the arc 17 from the current I flowing in the arc 17 and the magnetic field H. Also in this case, the arc 17 is bent and the arc extinguishing action becomes strong.

FIG. 3 is an enlarged cross-sectional view of the essential parts of a puffer type circuit breaker according to another embodiment of the present invention. Figure 2
The axial conductor 18B is also provided for the fixed arc contact 18 different from that of FIG.
A spiral conductor 18 in which the conductor is wound in a spiral shape on the lower side of the
A is provided. The spiral conductors 18A and 19A
And are wound in the same direction as each other. FIG. 7 is an enlarged sectional view of an essential part showing the magnetic field distribution around the separation gap 16 of FIG. The magnetic flux 21 flows in the opening gap 16 relatively along the axial direction (vertical direction), but since the arc 17 moves around in a complicated manner, the arc 17 and the magnetic flux 21 always cross each other. Also in this case, the Lorentz force acts on the arc 17 itself from the current I flowing in the arc 17 and the magnetic field H, and a strong arc extinguishing action acts on the arc 17.

FIG. 4 is an enlarged sectional view of the essential parts showing the structure of a puffer type circuit breaker according to a further different embodiment of the present invention. 3 is different from the configuration of FIG. 3 in that the movable arc contact 20 is provided with a spiral conductor 20A wound in a spiral shape above the hollow conductor 20B, and the spiral conductors 18A and 20A are wound in directions opposite to each other. Only points. Figure 8
FIG. 5 is an enlarged cross-sectional view of a main part showing a magnetic field distribution around the separation gap 16 of FIG. 4. Also in this case, the magnetic flux crosses the arc 17,
The Lorentz force acts on the arc 17 itself from the current I flowing in the arc 17 and the magnetic field H on this, 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 added to the arc in the opening gap by forming the arc contact in a spiral shape. Therefore, the required compressed gas amount can be reduced, and the device can be made compact. Also, the blocking capacity can be increased without increasing the amount of compressed gas.

[Brief description of drawings]

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

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

FIG. 3 is an enlarged sectional view of an essential part showing the configuration of a puffer type circuit breaker according to a further different embodiment of the present invention.

FIG. 4 is an enlarged sectional view of an essential part showing the configuration of a puffer type circuit breaker according to a further different embodiment of the present invention.

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

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

7 is an enlarged cross-sectional view of an essential part showing a magnetic field distribution around the separation gap shown in FIG.

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

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

10 is an enlarged cross-sectional view of the main part of FIG.

[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

Claims (3)

[Claims] 1. A fixed arc contact made of an axial conductor, and a fixed arc contact which is movable in the axial direction of the fixed arc contact in a tank filled with an arc-extinguishing gas and which is inserted into and taken out from the inner cavity of a hollow conductor. By disposing a fixed arc contact and a movable arc contact that separates by contacting the fixed arc contact, the arc generated in the separation gap between the fixed arc contact and the movable arc contact is blown out by compressed gas. Puffer type gas circuit breaker, characterized in that the movable arc contact side of is formed in a spiral shape. 2. A fixed arc contact made of an axial conductor, and a fixed arc contact which is movable in the axial direction of the fixed arc contact in a tank filled with an arc-extinguishing gas and which is inserted into and taken out from the inner cavity of a hollow conductor. A movable arc contact is provided in which a fixed arc contact and a movable arc contact that comes into contact with and separate from each other are arranged, and the arc generated in the opening gap between the fixed arc contact and the movable arc contact is blown out by compressed gas. A puffer type gas circuit breaker characterized in that the fixed arc contact side of is formed in a spiral shape. 3. The puffer type gas circuit breaker according to claim 2, wherein the movable arc contact side of the fixed arc contact is formed in a spiral shape.