JPH05290682A - Dc high speed circuit breaker - Google Patents

Abstract

PURPOSE:To break an arc within a short time and facilitate the miniaturization of a DC high speed circuit breaker. CONSTITUTION:On the upper part of an arc chute AS having a pair of arc hones AH and arc guides 22, 23, numbers of short and long vertically slender iron plates 31, 32 are alternately mounted at fixed intervals in such a manner that the lower ends are neatly arranged to constitute a cooling part 30. When an arc bridges numbers of the arc guides, the arc is blown up by the magnetic flux generated by the coil part of the central arc guide 22 and entered into the cooling part 30, in which the arc is cooled by numbers of the iron plates, current-decreased, and extinguished within a short time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a DC high speed circuit breaker, and more particularly, to a structure of an arc chute of the DC high speed circuit breaker.

[0002]

2. Description of the Related Art A conventional high speed circuit breaker (HSCB) is shown in FIG. In FIG. 6, the main circuit current I to be interrupted is 2 from the holding conductor 2 passing through the holding iron core FH to the fixed contact FC, the contact portion A, the movable contact MC, and the external iron core FT.
It is guided to the conductor 3 through the outside / arc blowout coil TC wound more than once.

At the opening end side of the holding iron core FH, an impactor AT forming a magnetic circuit together with the holding iron core is attracted to the holding iron core FH by a magnetic force Φ _H due to a current I.

On the other hand, the outer core FT forms a magnetic circuit together with the impactor AT through the air gap, and the impactor AT receives the magnetic force Φ _T generated by the current I in the outer core FT.

However, when the current I is small and the current increase rate di / dt is small, the magnetic aerodynamic force has a relationship of Φ _H > Φ _T , and therefore the impactor AT does not move while being attracted to the holding iron core side.

However, when the current I reaches a specified value (current scale value), or even if it is smaller than the specified value to some extent, d
When i / dt is large, the magnetic force becomes Φ _H <Φ _T , and the impactor A
T is detached from the holding iron core FH by the magnetic attraction force of the external iron core FT and moves to the attraction iron core FT side at a high speed. At that time, the impactor AT collides with the movable contactor MC, and the impact energy causes the movable contactor MC to be tripped and simultaneously moved in the iron core FT direction.

When the movable contact MC is separated from the fixed contact FC, an arc is generated from the arcing contact connected to the upper portion of the contact portion A. This arc is pushed up by the electromagnetic force generated by the external / arc blow-off coil TC, moves between the two arc horns AH, and is pushed up further into the arc chute AS.

The structure of this arc chute AS is shown in FIG. In FIG. 7, 11 and 11 have a length and width of about 30.
Insulation plate of 0 × 700 mm × about 500 ~ 1300 mm,
The arc chute AS chamber is constituted by the insulating plates 12 at both ends, which are arranged opposite to each other at an interval of about 30 to 70 mm.

In the arc chute AS, a pair of arc horns are provided at the lower part thereof, and a central arc guide 21 having a coil part C of one turn or several turns is formed at the center of the upper part thereof as shown in FIG. An insulating partition plate 2 is provided with a coil portion C vertically downward, and a V-shaped arc guide 23 fixed to the lower end on both sides thereof as shown in FIG.
5, 25 are provided in the radial direction away from the base of the arc horn AH.

As shown in FIG. 7, the arc generated at the time of interruption first moves to the arc horns AH and AH, and the central conductor 2
1 through the coil portion C. Therefore, an electromagnetic force is generated to further blow up the arc.

For this reason, the arc from one arc horn goes from one arc guide 23 to the central arc guide 21.
Through the other coil guide C and the other arc guide 23 to the other arc horn AH. Then, the arc sequentially shifts and extends in the direction of the arrow. As a result, the arc voltage rises, the direct current is forcibly limited, a current zero point is eventually created, and the arc is forcibly extinguished.

[0012]

In the DC high-speed circuit breaker, the difficulty in interrupting the DC current lies in how quickly the current limiting operation is performed to create the current zero point. However, in the case of the above-mentioned conventional arc chute, since the arc is blown upward and extended to limit the current, the current limiting action is not good even though the arc chute is large.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object thereof is to provide a cooling unit in an arc chute so as to interrupt the arc in a short arc time and to cut off the high-speed DC current. It is to provide a DC high-speed circuit breaker that enables downsizing of a switch.

[0014]

In order to achieve the above object, a high-speed DC circuit breaker according to the present invention has a pair of arc horns inside an arc chute and a coil part, and both tips are the uppermost ends of the arc chute. For a DC circuit breaker equipped with a central arc guide installed in a shape extending to the vicinity or an arc guide without a coil section between this arc horn and the central arc guide, both sides of the central arc guide or the length of the central arc guide A plurality of elongated iron plates are vertically attached to the upper portion of the cooling unit at a constant interval, and a cooling unit opened in the vertical direction is provided on the upper portion.

The length of the iron plates of the cooling section is alternately long and short, and the lower ends are aligned so that the gap between the iron plates in the upper half is approximately doubled.

Further, the arc guide is eliminated, and a plurality of long and short iron plates vertically elongated in the upper part of the arc chute provided with a pair of arc horns are alternately mounted so that the upper ends thereof are aligned at regular intervals. The outermost iron plate and the tip of the arc horn may be provided so as to overlap each other.

[0017]

[Operation] The arc pushed up by the electromagnetic force generated by the tripping and blow-off coil of the circuit breaker moves to the arc horn, then to the arc guide, and is composed of many iron plates due to the electromagnetic force generated by the coil part of the central arc guide. Since it enters the gap of the cooling unit and is cooled, it is quickly shut off.

If the gap between the iron plates above the cooling part is large, the arc is cooled in the cooling part and is extended by coming out from the narrow part of the gap to a wide part, so that it is quickly shut off. To be done.

When the arc guide is eliminated, no electromagnetic force is generated by the coil portion of the central arc guide, but since the outermost iron plate of the cooling part and the tip of the arc horn are provided so as to wrap, Since the arc block is eliminated and the distance between the iron plates is large at the bottom, the arc blown up by the electromagnetic force of only the trip and blow-off coil is smoothly cooled between the iron plates in the cooling section, so it can be quickly cooled. Shut off.

[0020]

Embodiments of the present invention will be described with reference to the drawings.
The same components as those shown in FIG. 7 of the related art are designated by the same reference numerals, and the duplicated description thereof will be omitted.

Embodiment 1 Referring to FIG. 1, reference numerals 30 and 30 designate a pair of arc cooling parts provided in the upper part of the arc chute AS, and as shown in FIG. The long and thin iron plate 31 with the same thickness as the iron plate 31 having the same thickness and length.
/ 2 to 2/3, a plurality of protrusions P are provided on both sides of the iron plate 32 in the up-down direction, and the protrusions P are fitted into the holes h alternately formed in the insulating plate 11 so that their lower ends are aligned. It is configured by mounting.

Reference numeral 22 is a central arc guide having a shape in which the length of the conventional central arc guide (FIG. 8) provided in the intermediate portion between the pair of arc horns AH and the arc cooling portions 30, 30 is shortened, and 23 and 23 are cooling portions. 30,30 and arc horn AH
Is an arc guide that is provided between and in the radial direction away from the base of the arc horn.

According to this embodiment, a DC circuit breaker (FIG. 6)
The arc that is generated at the time of shutting off, is blown up by the electromagnetic force of the pull-out and blow-off coil TC, and is transferred to the pair of arc horns AH moves upward between the pair of arc horns AH and at the same time, the arc guides 23, 22, Bridge 23.

Therefore, a magnetic flux in the axial direction of the coil portion C is generated by the current flowing through the coil portion C of the central arc guide 22, and the electromagnetic force further blows the arc upward. The blown-up arc is cooled by the cooling units 30, 3
The iron plates 31 and 32 of 0 enter the voids and are blown up further.

That is, the arc is sequentially moved in the direction of the arrow and extended, and at the same time, it is strongly cooled by the plurality of iron plates 31, 32. Therefore, the increase of the arc voltage is also strong,
The current limiting action of the direct current becomes strong, and the arc is extinguished with a low current limiting value and a short arc time.

Embodiment 2 Referring to FIG. 3, reference numeral 21 is a conventional central arc guide 21 of FIG.
The central arc guides 30 'and 30', which are constructed in the same manner as and are arranged in the arc chute AS, are central arc guides 2.
The arc cooling unit is arranged in the upper part of the interior of the arc chute AS so as to sandwich 1 ', and is constituted by alternately providing iron plates 31 and 32 like the arc cooling units 30 and 30 of FIG.
Since other configurations are the same as those of the first embodiment, the same reference numerals are given to the same components and the description thereof will be omitted.

According to this embodiment, the arc transferred to the pair of arc horns AH when the breaker is cut off is the arc horn A.
While moving upward between H, the arc guide 23, 2
Bridge 1 and 22. At this time, the electromagnetic force generated by the coil portion C of the central arc guide 21 blows up more strongly to the iron plates 31, 3 of the cooling portions 30 ', 30'.
Enter the void part of 2.

Therefore, the arc is strongly cooled by the iron plates 31 and 32, and the arc is extended and the arc voltage rapidly rises. At this time, the tip of the central arc guide 21 'extends to the uppermost portion of the arc chute AS. Therefore, the electromagnetic force of the coil C does not decrease until the arc current reaches the zero point and is cut off, so that a strong blowing effect is maintained.

Embodiment 3 In FIG. 4, 30 ″ is an arc cooling portion which is disposed in the upper portion of the arc chute and whose lower portion is positioned between both ends of the pair of arc horns AH. Alternately slender different iron plates so that their upper ends are aligned.
As shown in FIG.
It is configured by inserting into. The arc guide is omitted in the third embodiment.

According to this embodiment, the arc cooling unit 30 "
Is installed so that the coarser the iron plate is on the lower side and the denser is on the upper side, the arc moves to the pair of arc horns AH and then moves upward between the pair of arc horns AH. Then, it moves to the arc cooling unit 30 ″ which is sandwiched by the arc horn AH.

There is no iron plate 32 in the lower part of the arc cooling section 30 ", and the gap is the upper part of the iron plate 3 due to only the iron plate 31.
Since the gap formed by 1, 32 is twice as wide as the gap, the arc transferred to the arc cooling unit 30 ″ is promptly guided into the arc cooling unit 30 ″ and transferred to the upper portion.

For this reason, the arc is strongly cooled by the arc cooling unit 30 ", and the arc is rapidly extended and the arc voltage rapidly rises, and the direct current is rapidly limited, so that the current is forcibly cut off at the zero point.

[0033]

Since the present invention is configured as described above, it has the following effects.

(1) In the first to fourth aspects, the arc transferred to the arc horn is blown up by the electromagnetic force generated by the coil of the central arc guide and spreads to enter the cooling section. Due to the joint effect with the cooling effect of the iron plate, the arc voltage rises and the DC current limiting action becomes strong, and the arc is extinguished with a low current limiting value and a short arc time.

(2) In the fifth aspect, the cooling part is provided so that the outermost iron plate and the tip of the arc horn overlap, and the cooling part has a wide interval between the iron plates at the lower end. The arc pushed up by the electromagnetic force by the trip and blow-off coil quickly enters the cooling part and cools into the ridge part of the upper iron plate interval, so it is well cooled, current is limited, and the arc disappears in a short arc time. To do.

(3) With respect to claims 1 to 5, therefore, the arc chute can be made more compact.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an internal configuration of an arc chute according to a first embodiment.

FIG. 2 is an explanatory diagram of a configuration of a cooling unit.

FIG. 3 is an explanatory diagram of an internal configuration of an arc chute according to the second embodiment.

FIG. 4 is an explanatory diagram of an internal configuration of an arc chute according to the third embodiment.

FIG. 5 is an explanatory diagram of a configuration of a cooling unit.

FIG. 6 is a structural explanatory view of a conventional high speed circuit breaker.

FIG. 7 is an explanatory diagram of an internal configuration of a conventional arc chute.

FIG. 8 is a perspective view showing an arc guide.

FIG. 9 is a perspective view showing a central arc guide.

[Explanation of symbols]

 11 ... Insulating plate 21,22,23 ... Arc guide 30,30 ', 30 "... Cooling part 13,14,15,31,32 ... Iron plate AH ... Arc guide AS ... Arc chute C ... Coil part.

Claims (5)

[Claims] 1. A high-speed DC circuit breaker equipped with a pair of arc horns inside an arc chute, and a central arc guide having a coil portion in the center and both tip portions extending to a position near the uppermost end of the arc chute. In addition, the length of the central arc guide was shortened, and a plurality of vertically elongated thin iron plates were attached to the upper part of the arc chute at regular intervals to provide a cooling part opened vertically. High speed circuit breaker. 2. A high-speed DC circuit breaker equipped with a pair of arc horns inside an arc chute, and a central arc guide having a coil portion and having both tips extending to a position near the uppermost end of the arc chute. A DC high-speed circuit breaker, characterized in that a pair of cooling parts, which are vertically elongated, are attached to both sides of a central arc guide in the upper part of the arc chute, and are vertically attached to each other at regular intervals. 3. The high-speed DC cutoff according to claim 1 or 2, wherein the lengths of the iron plates are alternately long and short, and the lower ends are aligned so that the gap between the upper half of the iron plates is approximately doubled. vessel. 4. The high-speed DC circuit breaker according to claim 1, wherein one or a plurality of arc guides each having no coil portion are provided between each of the pair of arc horns and the central arc guide. 5. An arc chute provided with a pair of arc horns, and a plurality of vertically elongated long and short iron plates are alternately attached to the upper part of the arc chute so that their upper ends are aligned at regular intervals, and the outermost part of the cooling part is provided. DC high-speed circuit breaker, characterized in that the iron plate and the tip of the arc horn are wrapped.