JPH0629867Y2 - Gas circuit breaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an arc rotary type gas circuit breaker.

[Conventional technology]

Conventionally, as this kind of gas circuit breaker, there is one shown in FIG. 7, in which an insulating container (2) supported by a frame (1) accommodates blocking parts in a three-phase side-by-side arrangement, and the container (2 (3) is hermetically closed by the metal lid (3) through the O-ring (4), and the container (2) is filled with an insulating gas such as SF ₆ gas.

This blocking part is composed of a fixed contact (5) 'and a movable contact (6)' having a butt contact structure, and an upper part in which the fixed contact conductor (5) is provided through one side wall of the container (2). A flexible lead wire (9) is attached to the lower main circuit conductor (8) which is supported and connected to the main circuit conductor (7) and has the movable contact conductor (6) penetrating one side wall of the container (2). Connected through.

Here, the movable contactor conductor (6) of each phase is connected to the insulating support piece (1) on the opening / closing operation shaft (10) penetrating the container (2).
1) and are pressed and held by the contact pressure springs (12).

Further, immediately above the breaking portion, that is, immediately above the contact portion between the fixed contact (5) 'and the movable contact (6)',
A disc-shaped arc-extinguishing device (13) is provided for extinguishing the arc generated when the contacts (5) 'and (6)' are opened by high-speed rotation.

This arc extinguishing device (13) is, as shown in FIG. 8, an annular magnetic field generator in which a drive coil (14) and a permanent magnet (15) are combined, and a copper annular ring located on the lower surface of the magnetic field generator. The arc runner (16) and the fixed contactor conductor (5) are integrally molded with an insulating material (17) such as epoxy resin, and the fixed contactor (5) 'is a hollow portion on the arc runner (16) side. It is arranged near (18). Both ends of the coil (14) are connected to the arc runner (16) and the fixed contact conductor (5), respectively.

When the movable contactor (6) 'is separated from the fixed contactor (5)' in the closed state in the above-mentioned configuration, the initial arc (a) is generated between the contactors (5) 'and (6)'. At the same time, the foot of the arc (a) moves to the arc runner (16) along with the movement of the movable contactor (6) 'to become a commutation arc (b), and the arc current i changes to the fixed contactor (5). Is guided to the coil (14) between the ′ and the arc runner (16).

Therefore, due to the current flowing through the coil (14), a magnetic field is generated between the arc runner (16) and the movable contactor (6) located below the hollow portion (18), and the magnetic field of the permanent magnet (15) is commutated. A strong electromagnetic force, that is, a rotating force is applied to the arc (b), the arc (b) rotates at a high speed outside the hollow portion (18) of the arc runner (16) in an insulating gas atmosphere, and the arc (b) rapidly cools. And the arc is extinguished at the current zero point, and the interruption is completed.

[Problems to be solved by the invention]

By the way, as described above, both contact arcs (5) ′,
When the arc (a) generated by the separation of (6) 'moves to the arc runner (16), this arc (b) rotates under the influence of the magnetic field of the magnetic field generator, but at this time, the arc runner (16) The legs of the arc (b) in FIG. 9 tend to spread outward due to centrifugal force or the like, as indicated by the arrow in FIG.

Here, since the magnetic field generated by the magnetic field generator is weaker toward the outside of the arc extinguishing device (13), the rotational force applied to the arc (b) that spreads outward is reduced, and the arc (b) is reduced.
The problem that it becomes difficult to cut occurs, and the blocking performance deteriorates.

Further, the fixed contactor (5) 'at a position which penetrates the arc extinguishing device (13) and protrudes from the arc runner (16), which is the arc rotation surface, has a rectangular cross section due to the butt contact with the movable contactor (6)'. However, since electric field concentration is likely to occur at the corners of the fixed contactor (5) 'and the electric field strength increases, the hollow portion (18) is generated after the arc is generated.
There is an inconvenience that the internal voltage is likely to occur at the corners on the side (portions x and y in FIG. 9) due to the re-initiated voltage.

On the other hand, arcs (a) and (b) are formed between the movable contactor (6) 'and the fixed contactor (5)' or the arc runner (16).
Occurs, the insulating gas such as SF ₆ gas in this atmosphere is ionized by being heated and decomposed by the arc to generate hot gas.

This hot gas diffuses to the surroundings as the pressure rises, but especially when the small current is cut off, the hot gas does not diffuse so much and stays in the arc space.
There is a drawback that the dielectric strength in the arc space is reduced, and if the arc does not break easily, it will cause an accident.

This invention was made in consideration of the above points,
It is intended to provide means capable of solving these problems.

[Means for solving problems]

Next, the structure of the present invention for solving the above problems will be described with reference to FIGS. 1 to 3 corresponding to the embodiment.

A gas circuit breaker according to the present invention comprises an annular magnetic field generator arranged in an insulating gas atmosphere, a brim-shaped arc runner (16) provided on a lower surface of the magnetic field generator, and a side portion of the magnetic field generator. A fixed contact conductor (5) arranged from above to below, and formed at the lower end of the fixed contact conductor (5) and located near the lower part of the hollow part (18) of the arc runner (16). A fixed contactor (5) ', a movable contactor conductor (6) which rotates about a position below the fixed contactor (5)' as a fulcrum, and an upper end of the movable contactor conductor (6), When the movable contact conductor (6) is rotated, the movable contact conductor (6) comes into contact with and separates from the fixed contact (5) ', and when opened, the movable contact (6)' is located below the hollow portion (18). And the fixed contact in the arc rotation direction of the arc runner (16). On the front side of (5) ', in proximity to the fixed contactor (5)', an arc spreading preventing projection piece (19) 'partially protruding downward at the same potential as the arc runner (16) is formed. It is a thing.

[Action]

Then, the arc generated by the separation of the two contacts (5) ', (6)' causes the arc runner (1) from the fixed contact (5) '.
When moving to 6), a rotational force is applied to the arc under the influence of the magnetic field by the drive coil (14), and the arc rotates at a high speed outside the hollow portion (18) of the arc runner (16).

At this time, the legs of the arc try to spread to the outside of the arc runner (16), but the protruding piece (1
Since 9) 'is arranged on the front side of the fixed contactor (5) in the arc rotation direction, the leg of the arc that tries to spread to the outside has a protruding piece (19)' in front of the fixed contactor (5).
Alternatively, the arc is pulled back to the hollow portion (18) side, the spread of the arc is prevented, and the arc is rotated at a high speed in the peripheral portion of the hollow portion (18) where the magnetic field strength is large.

Further, since the protruding piece (19) 'is arranged close to the fixed contact (5), the electric field concentration around the fixed contact (5)' is relaxed by the protruding piece (19) '. .

Further, when the arc is generated as described above, the insulating gas in the arc space is heated and decomposed by the arc, and ionized hot gas is generated, which tends to diffuse to the surroundings as the pressure rises. Due to the fixed contact (5) 'on the outer circumference and the protruding piece (19)' adjacent to it, the gas does not diffuse uniformly to the surroundings, but diffuses in the opposite direction, and the hot gas is directed. Flow with nature,
The hot gas is replaced with the insulating gas promptly, the dielectric strength in the arc space is improved, and the insulation recovery characteristic is improved.

〔Example〕

Next, the present invention will be described in detail with reference to FIGS. 1 to 6 showing its embodiment. The same symbols as those used above indicate the same or corresponding ones.

First, FIGS. 1 to 4 showing one embodiment will be described.

In these drawings, the point different from the conventional one is that substantially L-shaped conductive projections (19), () are provided on both sides of the fixed contact (5) 'in the arc runner (16) of the arc rotary arc extinguishing device (13). 20) is attached with screws (21) and (22) so as to have the same electric potential as the arc runner (16), and the respective protruding pieces (19) 'and (20)' are attached to the hollow part (5) 'of the fixed contactor (5)'. The points are arranged in an eight-shape so as to be close to both corners on the 18) side and face the hollow part (18).

As shown in FIGS. 2 and 3, the projecting pieces (19) 'and (20)' have an inclination such that the fixed contact (5) 'side is high and the opposite side is low, and both ends are It is formed with roundness.

Therefore, the movable contactor (6) 'is fixed to the fixed contactor (5)'.
When the arc generated when the contacts are opened further moves to the arc runner (16), an arc current flows through the drive coil (14) that constitutes the magnetic field generator, and the movable contact (located below the hollow portion (18) ( 6) 'and Arkrunner (1
A magnetic field is generated during 6), and the arc is rotated at high speed by receiving the rotational force due to the electromagnetic force.

At this time, the legs of the arc in the arc runner (16) try to spread to the outside of the arc runner (16),
A protruding piece (19) 'having the same potential as the arc runner (16),
Since the (20) 'is located on both sides of the fixed contactor (5)', the arc causes the protruding piece (1) to be projected by the protruding piece (19) 'on the front side of the fixed contactor (5)' especially in the arc rotation direction.
9) ′, that is, the side of the hollow portion (18) is guided, and as shown by the solid line arrow in FIG.
It will rotate in the concentric circles outside.

This part has a strong magnetic field due to the coil (14), and as a result, the arc is subjected to a strong rotational force to rotate at high speed, is rapidly cooled, and is quickly extinguished at the current zero point.

Further, the ionized gas generated by the above-mentioned arc, that is, hot gas, is moved by the fixed contact (5) 'and both projecting pieces (19)', (20) 'in the direction of the one-dot chain line arrow in FIG. The hot gas, which has diffused to the surface and has a reduced dielectric strength, flows in a directional manner, and the surrounding insulating gas is smoothly replaced.

By the way, since the fixed contactor (5) 'has a rectangular cross section, the electric field is likely to be concentrated at its corners, but the protruding pieces (19)', which are inclined and rounded close to the two corners on the arc space side, respectively. Since (20) 'is located, the electric field distribution is significantly improved, the internal voltage is not entangled with the re-initiated voltage, and the insulation recovery characteristic is improved.

Next, FIGS. 5 and 6 showing other embodiments respectively.
The figure will be described.

As shown in FIG. 5, the fixed contactor (5) 'has a hollow portion (1).
8) A U-shaped conductive protrusion (23) is provided on the arc runner (16) so as to surround it from the opposite side to the screws (21), (2).
2), and projecting pieces (19) ', (20)' are formed on both ends of the projecting body (23), which are close to both sides of the fixed contact (5) 'and face the hollow part (18). The two projections (19) in FIG.
(20) has an integrated structure.

Further, FIG. 6 shows that the protrusion (19) is provided only on the front side of the fixed contact (5) 'in the arc rotation direction of the arc runner (16).

In this case, although the electric field relaxation effect around the fixed contactor (5) 'is slightly reduced as compared with the above-mentioned one, it is possible to surely prevent the arc from spreading to the outside and to diffuse the hot gas as shown by the dashed line in FIG. Can have directivity.

In the above description, the drive coil (1
4) was used, but when a permanent magnet was used,
Alternatively, a combination of the drive coil (14) and a permanent magnet as shown in the conventional example can be similarly implemented.

Further, the protruding piece (19) 'is not limited to the L-shaped screw stopper as described above, but may be any one having the same function.

Further, the protruding piece (19) 'is not limited to the conductive material, and may be an insulator (dielectric) such as Teflon. In this case, by attaching the protruding piece of the insulator to the arc runner (16), The protruding surface is an arc runner (1
It has the same potential as 6) and operates in the same manner as described above.

[Effect of device]

As described above, according to the gas circuit breaker of the present invention, the arc generated when the movable contactor (6) 'is separated from the fixed contactor (5)' is transferred to the arc runner (16) to generate a magnetic field. When rotating by the electromagnetic force of the magnetic field of the device, the arc can be prevented from spreading to the outside of the arc runner (16) by the protruding piece (19) ′ having the same potential as the arc runner (16), and the arc of the hollow portion (18) is prevented. The outer peripheral portion can be rotated at a high speed to quickly extinguish the arc, and the projecting piece (19) 'alleviates the electric field concentration around the fixed contact (5)' and improves the electric field distribution. In addition, the ionized gas generated by the arc has a directivity to allow the gas to be replaced quickly, improving the dielectric strength recovery characteristics in the arc space, and reducing the current from a small current range to a large current range. Blocking performance is obtained that, and in which can be improved interruption performance.

[Brief description of drawings]

1 to 6 show the essential parts of an embodiment of the gas circuit breaker of the present invention, FIGS. 1 to 4 show one embodiment, FIG. 1 is a bottom view, and FIG. 2 is a part. Rear view of cutting, FIG. 3 is a side view of cutting, FIG. 4 is a bottom view for explaining the operation, FIGS. 5 and 6 are bottom views of other embodiments, and FIGS. FIG. 7 shows a circuit breaker, and FIG. 7 is an overall cut side view, and FIGS. 8 and 9 are partial cut side views and bottom views, respectively. (5) …… Fixed contact conductor, (5) ′ …… Fixed contact,
(6) …… Movable contact conductor, (6) ′ …… Movable contact,
(14) …… Drive coil, (16) …… Arc runner,
(18) ... Hollow part, (19) '... Projecting piece.

Claims (1)

[Scope of utility model registration request] 1. An annular magnetic field generator arranged in an insulating gas atmosphere, a brim-shaped arc runner provided on a lower surface of the magnetic field generator, and a side portion of the magnetic field generator arranged from above to below. A fixed contact conductor that is provided, a fixed contact that is formed at the lower end of the fixed contact conductor, and that is located in the vicinity of the lower part of the hollow portion of the arc runner, and rotates around the position below the fixed contact as a fulcrum. And a movable contact conductor that is formed on the upper end of the movable contact conductor, and is in contact with and separated from the fixed contact by the rotation of the movable contact conductor, and is located below the hollow portion when opened. A movable contactor, and an arc spread preventing protrusion partially protruding downward at the same potential as the arc runner, on the front side of the fixed contactor in the arc rotation direction of the arc runner, in proximity to the fixed contactor. Moth that formed a piece Circuit breaker.