JPH02239528A - Gas circuit breaker - Google Patents

Abstract

PURPOSE:To offset electromagnetic force acting on arc so that the arc is stabilized at the center portion of the inside of a nozzle to obtain the good breaking performance of the gas circuit breaker by extending the extension conductors of a moveable contact portion from two opposite portions, and extending the extended conductors upwardly along a breaking portion and taking the conductors out of the breaker. CONSTITUTION:A fixed contact portion 8 is connected to the extension conductor 10a of an insulating spacer 3a by an extension conductor 9a so that it is guided to an external circuit. A moveable contact portion 6 has extension conductors 9b, 9c extended from two parts, and the extension conductor 9b and extension conductor 9c are positioned opposite to each other by about 180 degrees on the circumference. Both extension conductors 9b, 9c are extended in the direction of the fixed contact portion 8 and then connected integrally with each other by a connecting conductor 9d near above an insulating tube 7, and are connected to the extension conductor 10b of the insulating spacer 3b by an extension conductor 9e. Electromagnetic force against arc which force is caused by currents Ib, Ic separately flowing through respective extension conductors 9b, 9c is offset and the arc is allowed to exist stably at the center portion of the inside of the nozzle.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a tank-type gas circuit breaker which is a component of a gas insulated switchgear.

(Conventional technology) In recent years, due to the increase in demand for electricity mainly in urban areas, power transmission systems have become larger and more substations and switchyards have been built.Most of the switchgear used in these systems uses SF6 gas. On the other hand, with the development of an advanced information society, it has become even more important to stably supply large-capacity electric power.For this reason, the elements of gas-insulated switchgear (breakers , disconnectors, etc.) are now available in a wide variety of configurations, and a variety of circuit breaker configurations are now required.

Particularly, in order to reduce the size of the entire gas circuit breaker, the fixed contact part and the movable contact part are housed together with insulating gas in the same tank. When interrupting the short-circuit current I in the system, as shown in FIG. 4, the gas flow generated by the puffer mechanism 14 is blown onto the arc 13 generated in the fixed contact portion 8 and the movable contact portion 6 to cool it. to shut it off.

(Problem to be Solved by the Invention) However, when interrupting the current as described above, if the current to be interrupted is as large as the short circuit current of the grid, as in the conventional case (
In the case of a single lead-out conductor 9b, the current 1b flowing through the lead-out conductor 9b and the current Ia flowing through the lead-out conductor 9b.
Since the direction of the current flowing between the movable contact and the fixed contact is reversed, a strong electromagnetic force 15 acts on the arc 13.

Therefore, the arc 13 is bent as shown in the figure, and is biased within the insulating nozzle 16, so that it is pressed against one wall of the nozzle 16.

In a gas circuit breaker, good "ijA breaking performance can only be obtained by cooling the arc in the insulating nozzle with a substantially uniform gas flow from the surrounding area. As shown in Figure 4, the arc 13 is connected to the nozzle 16.
If the nozzle 16 is biased toward the inside, the gas flow from the buffer mechanism 14 will stop flowing on the side pressed against the wall of the nozzle 16, and the blocking performance will deteriorate.

An object of the present invention is to provide a gas circuit breaker that eliminates the influence of electromagnetic force during current interruption, reduces the reduction in interruption performance, and improves the interruption performance.

[Structure of the Invention] (Means for Solving the Problems) The gas circuit breaker of the present invention includes a movable contact portion and a fixed contact portion that can be brought into and out of contact with each other in a tank filled with arc-extinguishing dregs. In a gas circuit breaker, the conductor is pulled out from the contact part and the fixed contact part on the circumference of the body of the tank, facing each other with a difference of 180 degrees, and the lead-out conductor of the movable contact part 1a is directly below the fixed contact part in the direction in which the conductor is drawn out. The conductor was pulled out from two locations, one at a position opposite to the other at 180 degrees on the circumference, and the pulled out conductor was pulled up to the ground along the cut-off part and connected, and then pulled out from the tank's pull-out terminal. It is characterized by:

(Function) In the present invention k, 172 of the current flowing in the arc flows in each of the two lead-out conductors from the movable part in the opposite direction to the arc current. Therefore, the electromagnetic force acting on the arc is canceled out, and the arc is stabilized at the center within the nozzle. Therefore, the arc is uniformly cooled by the surrounding gas flow and good interrupting performance is obtained.

(Embodiments) The present invention will be explained below with reference to embodiments shown in FIGS. 1, 2, and 3. In FIG. The circuit breaker tank 2 is hermetically sealed with insulating spacers 3a and 3b, and has a circuit breaker 4 sealed therein together with a gas having good arc extinguishing performance and insulation performance.

The cutoff section 4 includes a movable contact section 6 provided via a ground insulating tube 5.
and a fixed contact portion 8 supported by an insulator (not shown) via an inter-electrode insulating cylinder 7. Although details are not shown, the movable contact portion 6 includes a movable contact, a movable arc contact, an insulating nozzle, and a puff 7.
The fixed contact portion 8 includes a fixed contact, a fixed arc contact, and the like.

Therefore, the present invention is characterized in that the current supply circuit including the fixed contact section 8 and the movable contact section 6 is improved.

That is, (1) the fixed contact portion 8 is connected to the lead-out conductor 10a of the insulating spacer 3a through the lead-out conductor 9a and led out to the external circuit. The movable contact part 6 has two lead-out conductors 9b and 9c pulled out, and one of the lead-out conductors 9a is at the same position as the lead-out conductor 9a of the fixed contact part 8, and the other lead-out conductor The position of 9C is on the circumference)
This is a position facing 180 degrees. Both lead conductors 9b
, 9c are pulled out in the direction of the fixed contact part 8, and then the third
As shown in the figure, they are connected together by a connecting conductor 9d surrounding about half the circumference near the top of the insulating cylinder 7, and then connected to the lead-out conductor 10b of the insulating spacer 3b by a lead-out lead-out 9e.

In the gas circuit breaker of the present invention configured in this way,
The current 1a flowing from the fixed contact part 8 to the movable contact part 4 passes through the movable contact part 6 and then is shunted to the lead-out conductors 9b, 9c to become currents 1b, Ic of Ia, /2, and the current direction is the opposite direction. become.

Therefore, the electromagnetic force exerted on the arc by the currents 1b and Ic is canceled out, and the arc stably exists at the center within the nozzle. When the arc is stabilized at the center of the insulating nozzle of the movable contact part 6, the low temperature gas from the buffer mechanism flows sufficiently around the arc, so that the arc is efficiently cooled and good interrupting performance is provided.

Another embodiment shown in FIG. 3 shows a gas circuit breaker for connection to a double-bus type gas insulated switchgear (GIS). Outside the outlet end 10b on the side of the movable contact portion 6, there is provided an outlet terminal 10c supported by an insulating spacer 3c below it.
b are connected by a lead-out conductor 9f. In the embodiment shown in FIG. 3, a short circuit current of 172 flows through the movable side lead-out conductors 9b and 9C during the breaking operation, so Nfn
This has the effect of weakening the force.

Note that in order to downsize the circuit breaker, the circuit breaker for three phases may be installed in one circuit breaker tank.

Even in such a three-phase integrated circuit breaker, if a structure is adopted in which the number of lead-out conductors on the movable contact part side is two, the electromagnetic force acting on the arc will be weakened, similar to the above embodiment, and the breaking performance will be improved. You can get the effect of

[Effects of the Invention] As described above, according to the present invention, the strong electromagnetic force caused by the short-circuit current prevents the arc being interrupted from being biased in the nozzle, so that a good cooling effect on the arc can be achieved. q
This makes it possible to improve the performance and downsize the circuit breaker.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the gas circuit breaker of the present invention;
Fig. 2 is an enlarged schematic diagram showing the lead-out conductor of the movable contact part of the gas circuit breaker, Fig. 3 is a sectional view showing another embodiment of the present invention, and Fig. 4 is the draw-out of the lead-out conductor of the conventional circuit breaker. It is a schematic diagram showing a state. 1... Drive device 2... Circuit breaker tanks 3a, 3b, 3C... Insulating spacer 4... Breaking part 5... Ground insulating cylinder 6... Movable contact part 7... Interpole insulation Cylinder 8...Fixed contact portions 9a to 9r...Outgoing conductor 10a, ? Ob, 10c --- Output terminal (8
733) Agent Patent attorney Yoshiaki Inomata (1 idiot) Figure 1

Claims (1)

[Claims] (1) A movable contact part and a fixed contact part that can be connected to and separated from each other are placed in a tank filled with arc-extinguishing gas, and the conductor is connected from the movable contact part and the fixed contact part approximately 180 degrees on the circumference of the body of the tank. In a tank-type gas circuit breaker, the lead-out conductor of the movable contact part is placed in two positions: one directly below the fixed contact part in the direction in which the conductor is drawn out, and the other in a position opposite to the fixed contact part at approximately 180 degrees on the circumference. A gas circuit breaker is characterized in that the conductor is pulled out from the tank, the pulled out conductor is pulled upward along the cutoff part, connected, and then pulled out to the outside from the drawer terminal of the tank.