JPH077624B2 - Puffer type gas breaker - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to an SF used in a substation or the like in a power system.
_{The present} invention relates to a gas circuit breaker containing an arc extinguishing gas such as ₆ gas.

[Technical background of the invention] High-pressure gas circuit breakers that blow an arc-extinguishing gas such as SF ₆ gas onto an arc easily withstand high voltages, and are therefore widely used. Among them, the puffer type gas circuit breaker that compresses the arc-extinguishing gas by utilizing the driving force when the contacts are opened is the mainstream of high-voltage circuit breakers because of its simple structure.

FIG. 3 shows a cross section in the vicinity of the arc extinguishing chamber of such a puffer type gas circuit breaker. The pair of opposing arc contacts comprises a fixed arc contact 1 and a movable arc contact 2. The movable arc contactor 2, the nozzle 3 formed around the movable arc contactor 2, and the puffer cylinder 4 are both connected to the operation rod 6. Puffer cylinder 4
Are extrapolated to the puffer piston 5.

With such a configuration, at the time of interruption, a command is sent to the drive unit, the operation rod 6 is driven by a force such as hydraulic pressure or a spring, and the movable arc contact 2, nozzle 3 and puffer cylinder 4 move. Due to this movement, the movable arc contactor 2 is separated from the fixed arc contactor 1 and an arc is generated between both contacts. On the other hand, the puffer cylinder 4 compresses the gas by the relative movement between the puffer cylinder 4 and the puffer piston 5, and the gas is blown to the generated arc through the nozzle 3. As a result, the arc is cooled and cut off at the current zero point.

In this way, the puffer type gas circuit breaker does not need to constantly hold high pressure gas unlike the two-pressure type circuit breaker, because compressed gas is produced with the opening operation.

[Problems of background art] However, on the other hand, in the puffer type, it is necessary to drive the puffer cylinder 4 against the differential pressure between the compressed gas and the ambient gas pressure. And this differential pressure is related to the current interruption capability of the puffer type gas circuit breaker. That is, as the breaking current increases, the current decrease rate at the current zero increases,
As a result, a higher pressure gas is required and a large drive energy is used with the current.

The drive energy of the puffer type gas circuit breaker is mainly composed of two components. One is kinetic energy for opening the whole at a constant speed, and the other is gas energy for gas compression. The latter has a large dependence on the breaking current, whereas the former has a high dependence on the voltage. That is, the higher the voltage, the higher the voltage applied between the contacts. For this reason, it is necessary to increase the opening speed and increase the gap length according to the voltage, such as in the case of progressive small current interruption, and the kinetic energy increases accordingly.

By the way, the increase of driving energy has a drawback that the driving part becomes large in size and the cost increases, and further, the mechanical stress to each part of the movable part is increased, so that there is a problem that a long life is impaired. . In addition, the acceleration to the base increases, and it becomes necessary to make the foundation stronger.

As described above, since the increase in driving energy causes various problems, it is an important subject to reduce the energy. Although it is difficult to reduce the kinetic energy of the driving energy as described above, various methods have been considered for the gas energy in the past.

It has been widely practiced to use the energy of the arc to increase the gas pressure in order to reduce the gas energy. However, in the conventional puffer type gas circuit breaker as shown in FIG. 4, no matter how the gas pressure is increased by the energy of the arc, this arc energy flows back to the puffer chamber and the pressure in the puffer chamber itself is increased. Since it acts as a reaction force of the puffer cylinder, after all, extra gas energy is required and it is difficult to reduce the gas energy.

On the other hand, a self-boosting type gas circuit breaker that does not perform the puffer operation at all is also considered, but in such a gas circuit breaker, pressure rise is not accompanied when the current is small, and the smaller the current is, the smaller the breaking performance is. Will cause a new problem that will decrease.

[Object of the Invention] The present invention has been proposed in view of the above-mentioned problems, and an object of the present invention is to reduce the gas energy as much as possible, thereby reducing the size of the driving portion and reducing the cost. It is an object of the present invention to provide an excellent puffer-type gas circuit breaker that reduces the mechanical stress on each movable part and also extends the life of the movable part.

[Summary of the Invention] The puffer-type gas circuit breaker of the present invention is provided with an envelope plate having a shape that covers from the outer peripheral surface of the movable arc contactor to the front of the tip end on the outside of the movable arc contactor attached to the tip of the operating rod. The tip of the puffer cylinder is attached to the outer periphery of the central part of the enclosing plate, and the nozzle that forms a gas passage with the enclosing plate is fixed to the outer periphery of the enclosing plate at the tip surface of the puffer cylinder by a nozzle retainer, so that the gas passage Is divided into a relatively wide passage inside the enclosing plate and a narrow passage between the nozzle and the enclosing plate to suppress an increase in gas pressure.

Then, the puffer cylinder is slidably inserted into a puffer piston fixed to a container or the like, and annular partition plates are provided on the drive part side of the enclosing plate and the tip end side of the puffer piston, respectively.
Both of them are slidably inserted into the inside and outside, and the outer partition plate has a hole for penetrating the inside and outside of the opening in the initial part of the opening. Since the applied cross-sectional area can be reduced, the contact can be opened with a small driving energy.

[Embodiment of the Invention] An embodiment of the puffer type gas circuit breaker according to the present invention as described above will be specifically described with reference to FIG. In addition,
The same parts as those of the above-mentioned conventional technique are designated by the same reference numerals and the description thereof will be omitted.

* Structure * FIG. 1 is a view showing a cross section in the vicinity of an arc extinguishing chamber of one embodiment of the puffer type gas circuit breaker according to the present invention.
₆ It is held via an insulator in a container containing gas.

In the figure, a fixed arc contactor 1 and a movable arc contactor 2 which are a pair of opposing contacts are arranged in the arc extinguishing chamber. The movable arc contactor 2 is fixed to the tip of the operation rod 6, and the operation rod is connected to a drive unit (not shown).

The operation rod 6 includes an envelope 10 having a shape including an outer peripheral surface of the movable arc contactor 2 to the front of the tip end thereof and having an opening at the tip end, which is provided coaxially with the movable arc contactor 2. The inner periphery of the tip end portion of the puffer cylinder 4 is mounted coaxially with the operating rod 6 on the outer periphery of the central portion of the envelope body 10. Therefore, the drive unit side half of the envelope body is included in the puffer cylinder 4. In front of the tip surface of the puffer cylinder 4, a nozzle having an outer peripheral surface of the tip half of the envelope 10 to the front of the tip to form a gas passage with the envelope 10 and having an opening at the tip. 3 is attached by a nozzle retainer 9. Further, holes 11 and 12 are provided in the axial direction at the connecting portion between the operating rod 6 and the envelope body 10 and at the connecting portion between the puffer cylinder 4 and the envelope body 10, respectively. The latter 12 penetrates the puffer chamber 13 and the inside of the envelope 10, and the second puffer chamber 14 on the outside and the gas passage inside the nozzle 3 (around the envelope 10), respectively.

The puffer cylinder 4 is slidably mounted on a puffer piston 5 fixed to the container via an insulator or the like. A partition plate 20 extends inside the puffer cylinder 4 on the drive portion side of the enclosure 10 and is inserted in a partition plate 21 extending toward the tip end side of the puffer piston 5. Further, several long holes 15 are provided on the tip end side of the partition plate 21 of the puffer piston.

In the figure, 7 is a fixed current-carrying contact, and 8 is a current collector.

* Operation * The operation of the present invention having the above-described configuration is as follows.

That is, when the breaker is closed, as shown in FIG. 1, the fixed arc contactor 1 and the movable arc contactor 2, and the fixed energization contactor 7 and the nozzle retainer 9 are in electrical contact with each other. When an opening command is given in this state, the drive unit operates and the operating rod moves in the opening direction. With this opening operation, first, the nozzle retainer 9 is separated from the fixed energizing contact 7, and then the movable arc contact 2 is fixed.
Then, an arc is generated between the contacts, and the gas inside the enclosure 10 is heated.

At the same time as the opening operation as described above, the gas in the puffer chamber is compressed by the relative movement of the puffer cylinder 4 and the puffer piston 5. This compressed gas passes through a hole 11 that communicates the inside of the enclosure 10 with the inner puffer chamber and a hole 12 that communicates the gas passage in the nozzle 3 with the outer puffer chamber, and the compressed gas in the enclosure 10 and the nozzle. Blow off into the gas passages respectively.
In this case, the gas in the enclosure 10 is heated by the heat of the arc and the pressure is rising, so until the current zero point is reached,
Backflow into the puffer chamber from the inside of the enclosure 10. At the initial stage of opening, the inner and outer first and second puffer chambers 13 and 14 are in communication with each other due to the long holes 15 provided in the second partition plate 21, so that the inner and outer puffer chambers 1 and 2 are connected. Chamber 13,14
Are compressed at the same pressure.

Then, in the latter half of the opening, as shown in FIG.
By the action of the second partition plates 20 and 21, the inner and outer first and
Since the second puffer chambers 13 and 14 are divided, each puffer chamber 1
3, 14 are independently compressed, and at the current zero point, the cooling gas is supplied from the outer puffer chamber 14 through the gas passage between the enclosure 10 and the nozzle 3, and is supplied from the inner puffer chamber 13 to the enclosure. Ten
High-pressure gas is released through the inside, and is blown to the arc to extinguish the arc.

Therefore, according to the present embodiment, by providing the enclosure 10 to divide the gas passages inside and outside, it is possible to suppress an increase in the gas pressure in the puffer chamber, and further by providing the partition plates 20 and 21, the reaction force due to the arc. Since it is possible to reduce the cross-sectional area to which the reaction force is applied by keeping the inside of the inner puffer chamber, it is possible to open the electrode with a small driving energy, the size of the driving unit can be downsized, and the cost can be reduced. Further, since mechanical stress on each part of the movable part can be reduced, it is possible to contribute to extension of life. Further, in the latter half of the opening, the high-pressure gas and the cooling gas are effectively supplied to act on the arc, so that the arc extinguishing performance can be improved.

The present invention is not limited to the above embodiment, and the shape and size of each member can be appropriately selected.

[Effects of the Invention] As described above, according to the present invention, the surrounding plate is provided around the movable arc contactor, and the partition plate is provided inside the puffer cylinder to divide the puffer chamber into the inner and outer puffer chambers in the latter half of the opening. With this configuration, the rise in gas pressure in the puffer chamber can be suppressed and the cross-sectional area to which reaction force is applied can be reduced. Therefore, the driving force for opening the electrode can be reduced, the cost can be reduced, and the service life can be extended. In addition, it is possible to provide a puffer type gas circuit breaker with improved arc extinguishing performance.

[Brief description of drawings]

FIG. 1 is a sectional view in the vicinity of an arc extinguishing chamber showing a closed state in an embodiment of the puffer type gas circuit breaker of the present invention, and FIG. FIG. 3 is a sectional view showing an embodiment of a conventional puffer type gas circuit breaker. 1 ... Fixed arc contactor, 2 ... Movable arc contactor, 3 ... Nozzle, 4 ... Puffer cylinder, 5 ... Puffer piston,
6 ... Operation rod, 7 ... Fixed energizing contact, 8 ... Current collector, 9
... Nozzle retainer, 10 ... Envelope, 11,12 ... Hole, 13,14 ... Puffer chamber, 15 ... Long hole, 20 ... Encircle divider, 21 ... Puffer piston divider.

Front page continuation (72) Inventor Satoru Yanagibu 2-1, Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Stock company Toshiba Hamakawasaki Plant (72) Inventor Edmon Chouly Piyujininyan, France (69640) Lieu de Versailles 34

Claims (1)

[Claims] 1. A pair of movable and fixed arc contacts are provided in a container in which an arc extinguishing gas such as SF ₆ gas is sealed, and the movable arc contacts are driven by a drive unit to open and close the contacts. , The puffer piston or puffer cylinder is driven at the same time as this movable arc contactor to compress the arc-extinguishing gas by the relative movement of the two, and the compressed arc-extinguishing gas is blown to the arc generated between the contacts to cut off the arc. In the puffer type gas circuit breaker, a movable arc contactor is attached to the tip of the operation rod connected to the drive part, and the outer side of the movable arc contactor from the outer peripheral surface to the front of the tip part is included on the outside thereof, and the opening part is provided at the tip. A puffer cylinder fixed to the container is attached to the outer circumference of the central part of the puffer cylinder that is coaxial with the operating rod. The nozzle that forms the gas passage between the puffer cylinder and the envelope is fixed to the outer circumference of the envelope by a nozzle retainer in front of the tip of the puffer cylinder, and the connecting portion between the operating rod and the envelope is fixed. In the connection portion between the nozzle and the puffer cylinder, holes are provided respectively through the puffer chamber and the envelope body, and through the gas passage in the puffer chamber and the nozzle, and further, the drive portion side of the envelope body and the tip end side of the puffer piston. , Each of which is provided with an annular partition plate, each partition plate is slidably inserted in and out, and the inner or outer partition plate end portion is provided with a hole for communication between the inside and outside in the initial opening stage. Puffer type gas circuit breaker.