JP2523475B2 - Puffer type gas breaker - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a puffer type gas circuit breaker in which an arc-extinguishing gas such as SF ₆ gas used in a power plant of an electric power system is enclosed.

[Technical background of the invention] High-pressure gas circuit breakers that blow an arc-extinguishing gas such as SF ₆ gas onto an arc are widely used because they easily withstand high voltages. Above all, the puffer type gas circuit breaker that compresses the arc-extinguishing gas by using the driving force at the time of contact opening and blows this compressed gas to the arc has a simple structure and in principle has excellent blocking performance. Therefore, in recent years, it has been widely used as a breaker for high-voltage power transmission lines.

The conventional structure of the arc-extinguishing chamber of such a puffer type gas circuit breaker is shown in FIG.

In FIG. 4, SF ₆ is contained in a container not shown.
A gas such as a gas having a good arc extinguishing property and an insulating property is enclosed, and the arc extinguishing chamber shown in FIG. 4 is housed therein. First, the pair of opposing arc contacts is composed of 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 fixed to the operation rod 6, and the operation rod 6
Is connected to a drive unit (not shown). In addition, the puffer cylinder 4 is a puffer piston 5 fixed to the container.
It is externally attached so that it can slide on. In the figure, 7 is a movable energizing contactor that fixes the nozzle 3, and 8 is a stationary energizing contactor.

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 energizing contact 7 and the movable arc contact 2, which are fixed to the rod 6, When the nozzle 3 and the puffer cylinder 4 move to the right in the figure, the movable energizing contact 7 first separates from the fixed energizing contact 8, and subsequently the movable arc contact 2 separates from the fixed arc contact 1. Then, an arc is generated between the two arc contacts 1 and 2. At the same time, the puffer cylinder 4
Compresses gas by relative motion with the puffer piston 5, and this compressed gas is sprayed through the nozzle 3 to the generated arc. As a result, the arc is cooled and cut off at the current zero point.

As described above, 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, and the structure is simplified as described above. Have.

[Problems of Background Art] However, on the other hand, the conventional puffer type gas circuit breaker has the following problems.

That is, in the buffer type, it is necessary to drive the puffer cylinder 4 against the pressure difference between the compressed gas and the surrounding gas pressure. This pressure difference is related to the current cutoff capacity of the puffer type gas circuit breaker. Therefore, when the breaking current becomes large, the current decreasing rate at the current zero becomes large, and as a result, a gas having a higher pressure is required, and a large driving energy is required together with the breaking current.

The drive energy of a puffer type gas circuit breaker is roughly 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 is highly dependent on the breaking current, whereas the former is highly dependent on the voltage. That is, the higher the voltage, the higher the voltage applied between the contacts. For this reason, for example, the opening speed is increased according to the voltage, such as advanced small current interruption,
It is necessary to increase the gap length, which increases the kinetic energy.

By the way, the increase in driving energy has a drawback that the driving part becomes large in size and the cost increases, and further, the mechanical stress on 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.

Since the increase of driving energy causes various problems as described above, it is an important issue 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 into the puffer chamber and the pressure of the puffer type itself is increased. Since it acts as a reaction force of the puffer cylinder, additional gas energy is eventually 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, the pressure is not increased when the current is small, There is a new problem that the performance is reduced.

[Object of the Invention] The present invention has been proposed in view of the above problems, and an object thereof is to improve the cut-off performance by enabling a configuration that can minimize gas energy. It is an object of the present invention to provide an excellent puffer-type gas circuit breaker that can reduce the cost by reducing the size of the drive part and also reduce the mechanical stress on each part of the movable part to extend the life.

[Summary of the Invention] The puffer type gas circuit breaker of the present invention is provided with a support member supported and fixed to a container around a connecting rod, a link is rotatably provided on the support member, and engaging holes are provided at both ends of the link. The connecting rod and the piston are provided with engaging portions that are inserted into the engaging holes at both ends of the link, respectively.When the contact is closed, the engaging hole of the link engages the engaging portion of the piston on the side opposite to the gas compression direction. When the contact is opened, the engaging hole of the link is configured to release the engagement of the piston with the engaging portion, and between the piston and the support member, the piston is always biased in the gas compression direction. It is characterized in that a spring is inserted.

With the above-mentioned configuration, when the circuit breaker is closed, the compression spring is compressed by driving the piston to the drive unit side via the link to maintain the gas compression chamber in a low pressure state and open it. At extreme times, the piston is released from the link and the biasing force of the compression spring drives the piston in the gas compression direction to perform gas compression. Therefore, gas energy can be reduced by accelerating gas compression without applying a reaction force to the drive unit. Further, since the amount of gas in the puffer chamber can be increased without increasing the opening distance, the blocking performance can be improved.

[Embodiment of the Invention] An embodiment of the present invention as described above will be described with reference to FIG. FIG. 1 shows a cross section of the puffer type gas circuit breaker in the vicinity of the arc extinguishing chamber. This arc-extinguishing chamber is SF ₆
It is held in a container filled with gas or the like through an insulator or the like. The same parts as those in the prior art shown in FIG. 4 are designated by the same reference numerals and the description thereof will be omitted.

* Structure * In FIG. 1, the connecting rod 9 that connects the operating rod 6 and the drive unit is provided with an engaging portion 9a, and the engaging portion 9a is formed at one end of the link 10. It is inserted in the hole 10a. Further, the link 10 has a fulcrum 10b on a support member 11 supported and fixed to a container (not shown),
Further, the engaging portion 12a provided on the movable piston 12 is inserted into the engaging hole 10c of the link 10 provided on the side opposite to the connecting rod 9 with respect to this fulcrum, and the link 10 includes the connecting rod 9 and the movable piston. With respect to 12, it is designed to slide and rotate within a predetermined range. Further, the movable piston 12 is supported by the support portion 11 via the compression spring 13. Movable piston 12
The inner peripheral portion of the movable rod 12 is airtightly slid on the outer peripheral portion of the operating rod 9, and the outer peripheral portion of the movable piston 12 is airtight on the inner peripheral portion of the puffer cylinder 4 which is coaxial with the operating rod 9 and is attached to the distal end portion of the operating rod 9. It is inserted to move.

* Operation * The operation of the present embodiment having the above-mentioned configuration is as follows.

That is, when the opening command is given in the closed state shown in FIG. 1, the connecting rod 9 is driven to the right in the figure in accordance with the operation of the drive unit (not shown). As a result, the operating rod 6 also moves, and the movable energizing contact 7 fixed to the operating rod 6 is separated from the fixed energizing contact 8 as shown in FIG. Then, the movable arc contactor 2 is separated from the fixed arc contactor 1, and an arc is generated between the two contactors. At the same time, the puffer cylinder 4 is also driven, and the relative motion with the movable piston 12 compresses the gas in the puffer chamber formed by the puffer cylinder 4 and the movable piston. Compressed gas is the nozzle 3
The arc is blown through the flow path between the movable arc contactor 2 and the arc, and the arc is extinguished.

The link 10 attached to the connecting rod 9 moves along with the opening operation, the movable piston 12 is released from the link 10 after a certain operation, and the compression spring 13 moves to the left in the drawing to compress the gas. To accelerate. In the open state, the movable piston 12 is held on the left side in the figure by the link 10 as shown in FIG.

On the other hand, when the closing command is given in the open state, the operation reverse to the above-mentioned operation is performed. At that time, the movable piston 12 engages with the link 10 and the link 10 moves in accordance with the operation of the connecting rod 9.
Driven via the, the compression spring 13 is compressed.

Therefore, according to this embodiment, when the contact is opened, the movable piston is released from the link and the movable piston is driven by the compression spring, so that the gas compression can be accelerated without applying a reaction force to the drive portion. Therefore, the gas energy can be reduced, the drive unit can be downsized, and the cost can be reduced.
It is also possible to extend the life by reducing the mechanical stress on each moving part. On the other hand, when the large current is cut off, the gas pressure rises to stop the operation of the movable piston, and when the pressure rises extremely, the compression spring can be further compressed to lower the gas pressure. The reaction force of can be reduced. Moreover, in this embodiment, the gas amount in the puffer chamber can be increased without increasing the opening distance, so that the cutting performance can be improved with a small driving force.

The present invention is not limited to the above embodiment, and the shapes of the link and the supporting member can be appropriately selected, for example.

[Effects of the Invention] As described above, according to the present invention, the reaction force to the drive unit is reduced and the amount of gas is reduced by the configuration in which the movable piston is accelerated at the time of opening by using the link and the compression spring. Therefore, it is possible to provide a puffer-type gas circuit breaker in which the gas energy is reduced, the drive unit is downsized, the cost is reduced, and the life is extended, while improving the blocking performance.

[Brief description of drawings]

1 to 3 are views showing an arc extinguishing chamber in one embodiment of the puffer type gas circuit breaker according to the present invention. FIG. 1 is a closed state, FIG. 2 is an open state, and FIG. FIG. 4 is a sectional view showing an open state, and FIG. 4 is a sectional view showing an arc extinguishing chamber 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 …… Movable energizing contact,
8 ... Fixed energizing contact, 9 ... Connecting rod, 10 ... Link, 11 ... Support member, 12 ... Movable piston, 13 ... Compression spring.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoru Yanagi 2-1, Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Toshiba Hamakawasaki Plant (72) Inventor Edmon Chiyuly Piyujinyan, France (69611) Lieu de Versailles 130 (56) Reference JP-A-52-383 (JP, A) JP-A-49-29465 (JP, A)

Claims (1)

(57) [Claims] 1. A container filled with an arc-extinguishing gas such as SF ₆ gas, provided with fixed and movable contacts arranged opposite to each other, and the movable contact is fixed to an operation rod which works in conjunction with a drive unit, and operated. A coaxial puffer cylinder that is coaxial with this is fixed to the rod, and between this puffer cylinder and the operating rod,
Nozzles having a puffer chamber formed by inserting pistons into the inner and outer peripheral portions of each of them so that they slide in an airtight manner, and surrounding the movable contactor to form a gas flow path and having an opening at the tip. In the puffer type gas circuit breaker fixed to the operating rod, a connecting rod that connects the operating rod and the drive unit is provided, and a supporting member that is supported and fixed to the container is provided around the connecting rod. The link is rotatably provided, the engaging holes are formed at both ends of the link, and the connecting rod and the piston are provided with engaging portions that are inserted into the engaging holes at both ends of the link, respectively.
When the contact is closed, the link engagement hole locks the piston engagement part on the side opposite to the gas compression direction, and when the contact is opened, the link engagement hole unlocks the piston engagement part. Further, a puffer type gas circuit breaker is characterized in that a compression spring for constantly urging the piston in the gas compression direction is inserted between the piston and the support member.