JPH0574895B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a puffer-type gas shatter breaker that has an improved arc extinguishing chamber configuration to improve shatter performance.

[Technical Background of the Invention] In recent years, with the increase in high voltage and capacity in electric power systems, the short circuit current that must be cut by a shunt breaker has rapidly increased, and the short circuit current that is applied to the shunt breaker after the current has been cut has increased rapidly. There is also a tendency for the applied voltage to increase more and more. In order to extinguish the arc that occurs when this current is interrupted, an insulating gas such as SF ₆ gas is compressed using a puffer device consisting of a cylinder, piston, and nozzle, and this compressed gas is blown into the arc. So-called patch-fire type gas shields and disconnectors, which extinguish the arc by attaching them, have been widely used.

FIG. 3 is a sectional view showing an example of the configuration of the arc extinguishing chamber of this type of puffer type gas shield and disconnector.
In the figure, 1 is a fixed arc contact provided in a container (not shown) filled with an insulating gas such as SF ₆ gas, 2 is a fixed current-carrying contact, and 3 is connected to and separates from the fixed arc contact 1. These are movable arc contacts that are freely disposed facing each other and supported at the tip of the operating rod 4. In addition, 5 is the movable arc contactor 3
A cylinder 5 moves together with the cylinder; 5 is a piston housed in the cylinder 5 and fixed in a container (not shown); 7 is a nozzle attached to the tip of the cylinder 5 outside the movable arc contact 3; 5, piston 6, nozzle 7
This constitutes a puffer device which compresses and sprays the insulating gas against the arc 8 generated between the arc contacts 1 and 3 during the arc breakage to extinguish the arc. Furthermore, 9 is a nozzle 7 from the cylinder 5.
This is a movable current-carrying contact provided on the outside thereof, and normally forms a current-carrying path with the fixed current-carrying contact 2 when turned on.

In such a puffer type gas shield breaker, the fixed arc contact 1 and the movable arc contact 3 are in contact when the shield breaker is in the closed state. At this time again,
The current mainly flows through the fixed current-carrying contact 2 and the movable current-carrying contact 9.
flowing through. On the other hand, when the current is cut off, the operation rod 4 moves and the fixed current-carrying contact 2 and movable current-carrying contact 9 are first separated, and then the fixed arc contact 1 and the movable arc contact 3 are separated,
An arc 8 is generated between each of the arc contacts 1 and 3. As the movable arc contact 3 moves away from the fixed arc contact 1, the insulating gas compressed by the fixed piston 6 and the cylinder 5 that moves together with the movable arc contact 3 is transferred to the movable arc contact 3. The gas is blown onto the arc 8 through a gas flow path formed between the child 3 and the nozzle 7 outside thereof, and is extinguished. The insulating gas that has passed through the arc 8 becomes a high-temperature gas, and the operating rod 4
The air is exhausted through the flow path inside the arc contactor 1 and the flow path toward the fixed arc contact 1 side.

[Problems with Background Art] Incidentally, in the above-mentioned puffer type gas shield disconnector, the nozzle 7 is provided to spray the insulating gas compressed by the piston 6 and the cylinder 5 onto the arc 8 at high speed. The portion 10 where the insulating gas blown from the surroundings collides becomes a stagnation point and the flow rate becomes extremely slow. Figure 4 shows
This figure shows the results of a simulation of this gas flow, and the length of the vector represents the flow velocity. From the same figure, the part 10 where the insulating gas blown from the surroundings collides and branches becomes a stagnation point,
It can be seen that the flow velocity is quite slow. As mentioned above, this type of blow-off type gas shielding and disconnecting device cuts and cuts the current by spraying insulating gas at high speed against the arc 8 and the high-temperature hot gas generated by this arc. Therefore, whether or not the arc breaker succeeds in interrupting the current depends on how quickly this hot gas is blown away and the low-temperature insulating gas is distributed between each arc contactor 1 and 3. It depends on whether you send it in or not. And from this point of view,
The formation of the stagnation point 10 where the flow of the insulating gas is slowed down in the area where a high electric field is applied between each arc contactor 1 and 3 will significantly improve the shear breaking performance of the shear breaker. This will result in a lower level of performance. In addition, a puffer type gas cylinder disconnector requires a large puffer chamber in order to obtain high blowing pressure.

[Object of the Invention] The present invention was made to solve the above-mentioned problems, and its purpose is to spray an insulating gas in a region where a high electric field is applied between fixed and movable arc contacts. It eliminates stagnation points that slow down the flow velocity of current flow, speeds up insulation recovery after current rupture, and improves insulation performance.In addition, the arc energy generated between each arc contact can be transferred to the power chamber. An object of the present invention is to provide a puffer-type gas insulator and disconnector which can make the puffer chamber smaller by effectively utilizing the increase in pressure.

[Summary of the Invention] In order to achieve the above object, the present invention includes a fixed arc contact, and a fixed arc contact disposed opposite to the fixed arc contact so as to be able to move toward and away from the container, the inside of which is filled with an insulating gas. A puffer-type gas shielding device comprising a movable arc contactor and a puffer device that compresses an insulating gas and extinguishes the arc generated between each arcing contactor when the current is interrupted by spraying it through a nozzle. In this device, a flow path for the insulating gas to be blown against the arc is formed on both the outside and inside of the movable arc contact, so that the flow of the insulating gas in the flow path is approximately in the same direction, and An inner flow path is formed from inside the cylinder of the puffer device through the inside of the operating rod that supports the movable arc contact, and a fixed arc inside the operating rod is formed near the communication port from the inside of the cylinder of the puffer device to the inside of the operating rod. A blind plate is placed on the opposite side of the contact.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention shown in the drawings will be described. FIG. 1 is a sectional view showing an example of the configuration of an arc extinguishing chamber in a puffer-type gas shield disconnector according to the present invention, and the same parts as in FIG. However, only the different parts will be described here. In the figure, the upper half shows the shrunken state, and the lower half shows the loaded state.

In other words, the arc extinguishing chamber according to the present embodiment is provided with a nozzle 11 having a linear cross-section with a smaller end diameter on the side that becomes the gas flow surface, as shown in the figure, in place of the nozzle 7, and the As shown in the figure, a flow guide 12 having a linear cross section and a small end diameter on the side that becomes the gas flow surface is provided on the outside of the movable arc contactor 3 while being supported by the nozzle 11, so that gas can be removed from the cylinder 5. A plurality of gas holes 4a are provided on the movable arc contactor 3 side of the operating rod 4 at regular intervals in the circumferential direction and communicating with the cylinder 5, while forming an outer flow path for the insulating gas to the blowing part. In particular, it is configured to form an inner flow path for insulating gas from inside the cylinder 5 through the inside of the operating rod 4 to the gas spraying section. In addition, in order to prevent the insulating gas that has flowed into the operating rod 4 from flowing in the opposite direction of the arc 8 (fixed arc contact 1), the non-movable arc contact A blind plate 13 is attached to the third side by welding or the like. Therefore, the insulating gas in the inner flow path and the outer flow path is unidirectional, that is, the fixed arc contact 1
It will only flow to the side. On the other hand, when simulating the gas flow, if the throat diameter D of the nozzle 11 is only about the same as the inner diameter d of the movable arc contact 3, the nozzle 11 and the flow guide 12
The flow of gas between the movable arc contactor 3 and the movable arc contactor 3 is pushed by the flow and hardly flows. Therefore, it is necessary to make the throat diameter D of the nozzle 11 larger than the inner diameter d of the movable arc contactor 3. However, if it is made too large, the pressure in the puffer chamber will not increase and the shearing performance will deteriorate.
Therefore, the throat diameter D of the nozzle 11 is set to be 1.2 times or more and 1.6 times or less (preferably about 1.4 times) the inner diameter d of the movable arc contactor 3.
In addition, the surfaces forming the flow paths of the nozzle 11 and the flow guide 12 are designed to smooth the flow of gas.
It is preferable not to have a curvature of R20 or less.

In the puffer type gas shield breaker having such an arc extinguishing chamber configuration, during the current cutting operation, that is, during the electrode opening operation, the movable arc contact 3 first comes out from the fixed arc contact 1, and then the nozzle 11 comes out. At this time, an arc 8 is generated between the fixed arc contact 1 and the movable arc contact 3 until the current reaches zero, and the gas heated by this arc 8 becomes high temperature and high pressure hot gas. , flows into the puffer chamber through the inside and outside of the movable arc contactor 3. That is, in this case, the communication port, that is, the gas hole 4a
By arranging the blind plate 13 close to the arc 8, the hot gas generated by the arc 8 flows into the puffer chamber from inside the movable arc contactor 3, thereby effectively reducing the pressure in the puffer chamber. This makes it possible to reduce the size of the power chamber.

On the other hand, during the above-mentioned opening operation, the insulating gas in the puffer chamber is compressed by the fixed piston 6 and the cylinder 5 interlocked with the movable arc contact 3. In this case, the compressed insulating gas is blown only from both the outside and inside of the movable arc contactor 3 toward the fixed arc contactor 1 side against the arc 8 generated when the current is interrupted. Since the insulating gas is sprayed at high speed to all areas where a high electric field is applied between each arc contactor 1 and 3, the flow of the insulating gas is slowed down and the arc 8 and A large stagnation point that would reduce the cooling rate of the hot gas generated by this arc 8 cannot be created. This makes it possible to more quickly recover the insulation between the arc contacts 1 and 3 after the current breaker breaks, thereby improving the breaker performance.

Incidentally, in the above embodiment, the blind plate 13 is attached as a separate body to the inside of the operating rod 4 by welding or the like, but they may be constructed in one piece.

[Effects of the Invention] As explained above, according to the present invention, the flow path of the insulating gas to be blown against the arc generated between the fixed and movable arc contactors when the current is interrupted is connected to the movable arc contactor. Formed on both the outside and inside of the air flow path so that the flow of insulating gas within the flow path is approximately in the same direction, and the flow path inside the movable arc contactor supports the movable arc contactor from within the cylinder of the puffer device. The arc contact is formed through the inside of the operating rod, and a blind plate is provided on the opposite side of the fixed arc contact inside the operating rod, which is close to the communication port from the inside of the cylinder of the puffer device to the inside of the operating rod. Eliminates stagnation points that slow down the flow rate of the insulating gas that is blown in areas where high electric fields are applied between the wires, which speeds up insulation recovery after current flow and breaks and improves insulation resistance. This is an extremely reliable puffer type gas shield and disconnector that can reduce the size of the puffer chamber by effectively using the arc energy generated between each arc contact to increase the pressure in the puffer chamber. Can be provided.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional configuration diagram showing one embodiment of the present invention;
Fig. 2 is a diagram for explaining the function and effect of the same embodiment, Fig. 3 is a cross-sectional view showing an example of the configuration of the arc extinguishing chamber of a conventional puffer-type gas shield and disconnector, and Fig. 4 is the same as that in Fig. 3. It is a figure which shows the result by simulation of a gas flow. DESCRIPTION OF SYMBOLS 1... Fixed arc contact, 2... Fixed current-carrying contact, 3... Movable arc contact, 4... Operation rod, 5... Cylinder, 6... Piston, 7,1
1... Nozzle, 8... Arc, 9... Movable current-carrying contact, 10... Stagnation point, 12... Flow guide, 13... Blind plate.

Claims (1)

[Scope of Claims] 1. A fixed arc contact, a movable arc contact disposed opposite to the fixed arc contact so as to be able to move toward and away from the fixed arc contact, and a container filled with an insulating gas. A puffer type gas shield and disconnector comprising a puffer device that compresses the insulating gas and extinguishes the arc by spraying it through a nozzle against the arc that sometimes occurs between the arc contacts, A flow path for the insulating gas to be blown is formed on both the outside and inside of the movable arc contact so that the flow of the insulating gas in the flow path is approximately in the same direction; The flow path
The stationary arc contact is formed from inside the cylinder of the puffer device and passes through the inside of the operating rod that supports the movable arc contact, and further, the fixed arc contact is formed inside the operating rod near a communication port from the inside of the cylinder of the puffer device to the inside of the operating rod. A Patshua-type gas shield disconnector characterized by a blind plate installed on the opposite side of the switch.