JPS6231920A - Buffer type gas breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a puffer type gas circuit breaker with an improved arc extinguishing chamber for improving the circuit breaker's circuit breaking performance.

[Technical background of the invention and its problems] As the demand for electricity increases, the capacity of power generation and substations continues to increase. Furthermore, due to the difficulty in constructing power plants in urban areas that consume a large amount of electricity, power transmission lines are becoming longer and there is a trend towards higher voltages in order to improve power transmission efficiency. As the capacity of power transmission systems increases, the breaking capacity required of circuit breakers used in substations and switchyards continues to increase, and currently, in 550KV systems, circuit breakers with a breaking current of 63 are in practical use. has been made into

This 550K V-63K A is configured with 4 points of cutting, and if this is applied to the 1000K V system as is, it will correspond to 8 points of cutting. In order to improve reliability iI4 of the circuit breaker, it is important to reduce the number of breaking points and the number of parts as much as possible. For this purpose, it is necessary to increase the breaking capacity per continuous disconnection point.

For power transmission voltages of 168 KV or higher, puffer-type SF6 gas circuit breakers are mainly used. This is due to the excellent blocking performance and insulation performance of SF6 gas, but especially 2
Compared to the loaf type, the puffer type has a simpler structure, so it has become the mainstream of high voltage circuit breakers.

In addition, in closed type gas switchyards where the entire substation equipment is insulated with SF6 gas, puffer type gas shut-off is particularly useful, as it has advantages in terms of insulation coordination with other equipment, equipment placement, etc. The utensils are often used.

This puffer-type gas circuit breaker is a power circuit breaker that uses insulating gas to extinguish arcs. It uses a puffer cylinder and piston that are linked to the movement of a movable contact to create pressurized insulating gas. It is designed to extinguish the arc by blowing insulating gas onto the arc that is generated during the interruption.

One way to improve the breaking performance of such an SF6 gas circuit breaker is to increase the opening speed between the electrodes. This can be achieved by increasing the driving force, but this leads to an increase in the size and cost of the drive device. It is also possible to increase the speed by elevating the movable parts, but there are limits to this. On the other hand, when the opening speed is increased, new problems arise such as SFi, reliability of the seal sliding part between gas and air, and strong electric shock of each member.

[Objective of the Invention 1 The object of the present invention is to obtain a faster opening speed than the conventional one with approximately the same driving force as the conventional one, and to improve the insulation recovery characteristics of the opening.
An object of the present invention is to provide a puffer-type gas circuit breaker that sprays a gas flow onto an arc at a higher speed than the conventional one, thereby shortening the arc time.

[Summary of the Invention] A puffer type gas circuit breaker according to the present invention includes a fixed contact portion configured by providing a fixed arc electrode on a conductive member, and a fixed contact portion that is connected to the arc electrode at the tip of an operating rod that is moved back and forth by an operating mechanism. A movable contact section is provided with a movable electrode that is separated from the movable electrode, which is surrounded by a gas passage, and is further provided with a puffer mechanism that performs a bellows action by advancing and retracting the operating rod. In the arranged puffer-type gas circuit breaker, the conductive member of the fixed contact part is slidably connected to the fixed current-carrying conductor, the arc electrode is surrounded by an insulating guide via the chamber part, and the movable contact part is roughly connected to the conductive member of the movable contact part. The insulating nozzle is slidably assembled so that the insulating nozzle changes the chamber volume according to the direction of the insulating material, and a throat portion on which the arc electrode slides is provided in the middle of the insulating nozzle, and the throat portion is provided between the operating rod and the fixed contact portion. Operation [1
The present invention is characterized by a link mechanism that transmits the movement of the joint so that the inner contact portions move in opposite directions.

[Embodiments of the Invention] The present invention will be described below with reference to embodiments shown in FIGS. 1, 2, and 3. FIG. 1 shows the puffer type gas circuit breaker according to the present invention in a closed state, FIG. 2 shows a state in the middle of shutting off, and FIG. 3 shows a shut off state. In FIG. 1, the puffer type gas circuit breaker according to the present invention is constructed by disposing a fixed contact part 1 and a movable contact part 2 facing each other in a container filled with an insulating gas of 8F6 gas.

The fixed contact part 1 has a fixed arc electrode 3 on a conductive member 3a.
This arc electrode 3 is surrounded by an insulating guide 4. Further, the arc electrode 3 of the conductive member 3a
A current-carrying cylindrical body 5 is mounted on the opposite side, and the current-carrying cylinder 5 is movably connected to, for example, a current-carrying conductor 6 protruding from an eye bushing (not shown).

The movable contact portion 2 includes a movable electrode 9 that contacts and separates from the arc electrode 3 at the tip of a hollow operating rod 8 that is connected to an operating mechanism (not shown) via an insulating rod 7, and a movable electrode 9 connected to the arc electrode 3 via a gas passage 10. It is constructed by providing a surrounding insulating nozzle 11 and further providing a padua mechanism 14 that forms a puffer chamber 14a with a puffer cylinder 12 and a puffer piston 13. The insulating nozzle 11 and the insulating guide 4 have a combination structure that slides in conjunction with the movement of the movable electrode 9 and the arc electrode 3 as shown in the figure. Using this, a chamber 26 is formed around the arc electrode 3 as shown in FIG.

The puffer screw 13 of the puffer mechanism 14 has a base 16 attached to an insulating cylinder 15 that is a stationary part surrounding the insulating rod 7.

Therefore, in the present invention, a link mechanism 17 is provided between the operating rod 8 and the conductive member 3a so that the fixed contact portion 1 and the movable contact portion 2 move in relatively opposite directions during the closing or closing operation. . This link mechanism 17 includes a lever 17a rotatably connected to a link support portion 18 protruding from a fixed base 16 through a shaft 19 at the center, and one end rotatably connected to the lever 17a through a shaft 20. A shaft rod 22 whose end is connected to a conductive member 3a of an arc utility pole 3 via an insulating rod 21
The link 17b is rotatably connected to the operating rod 8 by a shaft 23, and one end is rotatably connected to the operating rod 8 by a shaft 24, and the other end is rotatably connected to the operating rod 8 by a shaft 23.
Link 1 rotatably connected to the other end of lever 17a at 5
It is configured in combination with 7c.

Next, the operation of the puffer type gas circuit breaker according to the present invention will be explained. In the closed state shown in FIG. 1, when the operating rod 8 is driven rightward in the figure at a certain speed by the insulating rod 7 of the operating mechanism (not shown), the movable electrode 9 moves the arc electrode 3
21, where the throat 11a of the insulating nozzle 11 is also separated from the arc electrode 3. In this state,
The puffer chamber 14a is compressed and the compressed gas flows through the passage 10.
It is blown through the arc A between the electrodes 3.9.

On the other hand, the driving force of the operating rod 8 is transmitted to one end of the lever 17a via the link 17c. At this time, lever 17
The lever a rotates in response to a rotational moment about the fulcrum 19, and moves the link 17b connected to the other end of the lever 17a and the insulating rod 21 connected to the link 17b to the left. Along with this, the opposing arc electrode 3 also moves to the left to perform the interrupting operation. At this time, the directions of the interruption operations between the arc electrode 3 and the movable electrode 9 are relatively opposite, so that the opening speed becomes relatively high, which helps improve the interruption performance.

At this time, the insulating nozzle 11 and the insulating guide 4 are all on the right,
Due to the relative movement to the left, the gas within the chamber 26 expands rapidly and a large negative pressure is generated. This state is maintained until the throat 11a of the insulating nozzle 11 separates from the opposing arc electrode 6, as shown in FIG. At the same time as the throat 11a is formed, the flow path 10 and the chamber 2 are
6 communicates with each other, and the gas in the puffer chamber 14a is blown into the arc A at high speed due to the pressure difference between the two.The pressure in the chamber 26 rises to the same level as the pressure in the container. Then, the insulating nozzle 11, the insulating guide 4, and the fitting portion are separated, and the gas that has passed through the throat 11a is blown out into the container.

As a result, the shutoff complete state shown in FIG. 3 is reached.

FIG. 4 shows a characteristic S1 of the relative displacement between the movable electrode 9 and the arc electrode 3 during the interruption operation, and temporal changes in the gas pressure P1 in the puffer chamber 14a and the gas pressure P2 in the chamber 26. 80 points in Fig. 4 are insulated nozzle 1 as shown in Fig. 2.
This shows the point in time when the throat portion 11a of No. 1 passes through the tip of the arc electrode 3. That is, the throat portion 11a is the second
In the position shown in the figure, the pressure P2 in the chamber 26 is at the maximum negative pressure state, and the pressure P1 in the puffer chamber 14a is in the process of rising. Then, after the chamber 26 reaches a sufficiently negative pressure state, the compressed gas of sufficient pressure in the puffer chamber 14 is blown into the negative pressure chamber 26.

On the other hand, the closing operation is completely opposite to the closing operation, and the state shown in FIG. 3 shifts to the state shown in FIG. 7. During this operation, the gas in the chamber 26 formed by the fitting of the insulating nozzle 11 and the insulating guide 4 is compressed, but because the relative speed between the two is slow, the small hole 27 causes the pressure inside the chamber 26 to be reduced. is kept approximately equal.

In this manner, in the breaking and closing operations, the moving directions of the movable electrode and the opposing arc electrode are always opposite, so that the separation speed and approach speed of both can be relatively high. Additionally, a negative pressure can be built up in the chamber around the counter-arc electrodes before the puffer pressure builds up sufficiently, and the pressure differential provides a high-velocity gas flow for a fairly long period of time.

[Effects of the Invention] As explained above, according to the present invention, the relative speed between the electrodes can be increased with the same driving force as the conventional one, so the insulation recovery characteristics between the electrodes are improved, and the rated voltage is extremely high. Even when the current is high, it is possible to perform current connection and disconnection with fewer interruption points. Furthermore, since a high-speed gas flow is obtained from the time when the opposing electrodes are separated, the arc time can be shortened compared to the conventional method, reducing wear and tear on the electrodes and nozzles, and providing a long-life interrupting section. On the other hand, if the arc time is maintained at the same level as before, the diameter of the puffer cylinder can be made smaller, and therefore the diameter of the tank can also be made smaller.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of the arc extinguishing chamber in a closed state showing an embodiment of the puffer type gas circuit breaker according to the present invention, FIG. The cross-sectional view shown in FIG. 4 is a characteristic diagram showing the electrode displacement and gas pressure change of the puffer type gas circuit breaker of the present invention. 1... Fixed contact part, 2... Movable contact part 3.
...Fixed side arc electrode 4...Insulated guide, 3a...Conductive member 5.
... Current-carrying cylindrical body, 6 ... Current-carrying conductor 7 ... Insulating rod, 8 ... Operating rod 9 ... Movable electrode, 11 ... Insulating nozzle 11a slow part, 14 ...
・Puffer mechanism 14a...Puffer chamber, 17...Link mechanism 21...Insulating rod, 26...Chamber
i (8733) Agent Patent Attorney Yoshiaki Inomata (and 1 other person)

Claims (3)

[Claims] (1) A fixed contact portion configured by providing a fixed arc electrode on a conductive member, and a movable electrode that comes into contact with and separates from the arc electrode at the tip of the operating rod that is moved back and forth by the operating mechanism, and a movable electrode that contacts and separates from the arc electrode. In a puffer-type gas circuit breaker, in which a movable contact part surrounded by a gas passage and configured with a puffer mechanism that performs a bellows action by advancing and retracting an operating rod is disposed facing each other in an arc extinguishing chamber, the fixed contact part A conductive member is slidably connected to a fixed current-carrying conductor, the arc electrode is surrounded by an insulated guide via a chamber part, and an insulated nozzle of the movable contact part is connected to the insulated guide to change the chamber volume. In addition to being slidably combined, a throat part for sliding the arc electrode is provided in the middle thereof, and further between the operating rod and the fixed contact part, the movement of the operating rod is controlled so that both contact parts move in mutually opposite directions. A puffer-type gas circuit breaker characterized by being provided with a link mechanism that transmits transmission. (2) The throat part of the insulating nozzle is provided at a position where the volume of the chamber part reaches the maximum negative pressure at the time of passing through the arc electrode, and the pressure of the puffer chamber reaches the maximum after this point. A puffer type gas circuit breaker according to item 1. (3) The link mechanism includes a lever pivotally connected to a plurality of link support members disposed around the operating rod, and each link rotatably connecting one end of each lever to the operating rod; Claim 1, characterized in that it is constituted by links rotatably connecting the other end of each of the levers and a conductive member carrying an arc electrode of the fixed contact part through an insulating rod. Puffer type gas circuit breaker as described in section.