JPH0795414B2 - Puffer type gas circuit breaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention is used in a substation or a switching station of a power system.
The present invention relates to a puffer type gas circuit breaker using SF6 gas as an arc extinguishing medium.

(Prior Art) A puffer type gas circuit breaker has a structure shown in FIG. In this system, the puffer cylinder moves in the case of FIG. 3 with the opening / closing operation of the contacts, and the puffer chamber is compressed by the relative movement with the puffer piston. At this time,
A high-pressure gas is created in the puffer chamber, and when this gas is blown out through a nozzle, a high-speed gas flow is created, and this is blown onto the arc to cool and extinguish the arc. In this way, since the high-pressure gas is produced by the puffer operation associated with the opening / closing operation, it is not necessary to store the high-pressure gas like a two-pressure type circuit breaker and it is not necessary to control the blowing, and the structure is simplified. It has a great advantage. SF6 is used as an arc extinguishing gas.
Since gas is used, the insulation performance is excellent, and today it is the mainstream of high-voltage circuit breakers of 72 kV or higher.

One of the severe breaking conditions for puffer-type gas circuit breakers is the so-called advanced small-current breaking, which cuts off the charging current of unloaded transmission lines and cables. Since the current value is as small as several tens to several hundreds of amperes in advanced small current interruption, the puffer type gas circuit breaker can even interrupt the current zero point immediately after opening. As for the cutoff word, a DC voltage remains on the line side, and a voltage of 1–cos θ is applied between the poles of the circuit breaker due to changes in the power supply voltage. Therefore, at the shortest, twice the peak value of the rated voltage is applied 8 to 10 ms after opening. That is, since a high voltage is applied to a very small gap, dielectric breakdown may occur. When dielectric breakdown occurs, abnormal voltage will be generated.
In high-voltage systems, it is a condition that such dielectric breakdown, so-called re-ignition, does not occur.

In order to prevent such re-ignition, some circuit breakers for ultra-high voltage systems employ a double motion system as shown in Fig. 4. Since re-ignition occurs because a high voltage is applied to the small gap, it is effective to increase the contact opening speed. However, in the puffer type, as the contact opening speed increases, the reaction force of the puffer also increases, so it is huge. You will need a driving force. Therefore, the system shown in FIG. 4 is intended to increase the relative speed by driving the fixed electrode in the direction opposite to the movable side.

(Problems to be solved by the invention) However, in such a method, it is necessary to drive not only the arc electrode but also the energizing contact on the fixed side. This is because if the fixed side is driven by the arc electrode only, the arc electrode gap can be obtained sufficiently, but the gap on the energizing contact side cannot be obtained, and in the end, re-ignition will occur on the energizing contact side. . Therefore, the weight of the movable part becomes large, and as a result, the driving force cannot be reduced.

In view of the above points, the present invention aims to reduce the driving force of the double motion system.

[Structure of the Invention] (Means for Solving the Problems) In the present invention, the movable energization contact arc 8 is fixed to the container together with the fixing portion via an insulator or the like, and the fixed arc contact 7
1 is a fixed side link 30 for connecting the fixed arc contactor 7 to an insulating rod 29 supported by the operating rod 16 via a movable side link 28, as shown in FIG. The structure is such that it reciprocates so that the fixed arc contactor 7 moves in the same direction as the movable part in the initial stage of contact opening, and then moves in the opposite direction.

(Operation) The drive unit operates the opening station according to the opening command. This operation is transmitted to the operating rod 16, and the movable energizing contact 8 is first separated from the fixed energizing contact 5. Insulation rod 29
The link 30 causes the fixed arc contact 6 to move in the same direction as the movable part. When the link 30 is reversed and the fixed arc contact 7 moves in the direction opposite to the moving part, the fixed arc contact 6 is separated from the movable arc contact 7 and the arc 20
Cause During this time, the puffer chamber 15 is compressed by the relative movement of the puffer cylinder 13 and the puffer piston 14, and the gas in the puffer chamber 15 cools the arc 20 blown out from the nozzle 11 through the gas passages 13a, 12a and the arc at the current zero point. 20 is extinguished. At this time, the movable part has already obtained a considerable opening speed, while the fixed arc contact 6 is moving in the opposite direction to the movable part, so that the relative separation speed becomes extremely high.

(Embodiment) The configuration of the present invention will be described based on an embodiment shown in FIG. The fixed portion supported by an insulator or the like in the container has a fixed energizing contact 5 covered with a shield 9. The fixed arc contactor 6 is movably supported by the fixed portion. The fixed arc contactor 6 and the fixed current-carrying contactor 5 face the movable arc contactor 7 and the movable current-carrying contactor 8, respectively.
The movable arc contactor 7 is supported by the operation rod 16 together with the puffer cylinder 13. The operating rod 16 is connected to a drive unit (not shown). Between the operating rod 16 and the puffer cylinder 13 is a puffer piston supported by an insulator or the like.
14 is inserted. A nozzle 11 is provided on the front surface of the puffer cylinder 13 so that the movable arc contactor 7 is covered therewith.
Fixed by. A gas passage 12a is formed between the movable arc contactor 7 and the nozzle 11, and the puffer cylinder 13
The gas passage 13a is connected to connect the puffer chamber 15 and the opening of the nozzle 11. Movable side link for operation rod 16
An insulating rod 29 is supported via 28, and a fixed arc contact 6 is connected to the insulating rod 29 via a fixed side link 30.

The operation of this embodiment will be described. The drive unit performs the opening operation according to the opening command. This operation is the operation rod 16
The movable current-carrying contact 8, the fixed arc contact 6, and the movable arc contact 7 are transmitted according to the characteristics shown in FIG. First, the movable energizing contact 8 is separated from the fixed energizing contact 5. At this time, the insulating rod 29 moves in the direction opposite to the movable part by the movable side link 28, and the fixed arc contact 7 moves in the same direction as the movable part by the fixed side link 30. Next, when the fixed lever 30a of the fixed side link 30 is reversed, the fixed arc contactor 6 moves in the direction opposite to the movable part, and the movable arc contactor 7 separates from the fixed arc contactor 6 to generate the arc 20. During this time, the puffer chamber 15 is compressed by the relative movement of the puffer cylinder 13 and the puffer piston 14, and the gas in the puffer chamber 15 passes through the gas passages 13a and 12a to cool the extinguishing arc 20 from the nozzle 11 and extinguish it. When the contacts are opened, the movable part has already moved at a considerable speed, and when combined with the movement of the fixed arc contact 6, the relative opening speed becomes extremely high.

The operation of the fixed link 30 will be described. Movable link
Regarding the action of 28, the insulating rod 29 moves in the direction opposite to the movable part. As a result, the fixed lever 30a of the fixed link 30 has a fulcrum 30e.
Is rotated about the center of the movable part and the fixed arc contactor 6 is moved in the same direction as the movable part via the movable lever 30b. If this operation continues for a while, the fulcrum of the fixed lever 30a and the movable lever 30b moves to the outside of the fulcrum 30e of the fixed lever 30a.
This means that the fixed lever 30a is reversed, and thereafter the fixed arc contactor 6 is moved in the direction opposite to the movable part.

The effects of this embodiment will be described. In this way, the movable side link 28 moves the insulating rod 29 from the movable side in the direction opposite to the movable portion, and the fixed side link 30 connected to this is moved.
By the action of, the fixed arc contactor 6 movably supported by the fixed part moves in the direction opposite to the movable part in the initial opening stage, and moves in the same direction as the movable part after the fixed side link 30 is reversed. By doing so, it is possible to eliminate the need to move the fixed energization contactor 5 while it is fixed to the container, which is effective in reducing the driving force of the double motion system, and the fixed energization contactor 5 can be attached to the container. The structure can be simplified because there is no need to move it while it is fixed.

EFFECTS OF THE INVENTION According to the present invention, the movable side link 28 moves the insulating rod 29 from the movable side in the direction opposite to the movable part, and the fixed side link 30 connected to this moves the insulating rod 29 to the fixed part. By allowing the freely supported fixed arc contactor 6 to move in the direction opposite to the moving part at the initial stage of contact opening, and to move in the same direction as the moving part after the fixed side link 30 is reversed, fixed energization contact is achieved. Even if the child 5 does not need to be moved while being fixed to the container, the relative contact opening speed after contact opening can be increased, and the withstand voltage on the energizing contact side can be kept higher than that on the arc contact side.
It is effective in reducing the driving force of the double motion method, and since the fixed energizing contact 5 does not need to be moved while being fixed to the container, the structure can be simplified, and the circuit breaker can be downsized and the driving force can be reduced. It is effective.

[Brief description of drawings]

FIG. 1 is a diagram showing the vicinity of contacts of a puffer type gas circuit breaker according to the present invention, FIG. 2 is a diagram showing the operation of the present invention, and FIG. 3 is a diagram showing the structure of a conventional puffer type gas circuit breaker. . 5 ... Fixed energizing contact, 6 ... Fixed arc contact 7 ... Movable arc contact, 8 ... Movable energizing contact 9 ... Shield, 11 ... Nozzle 12a, 13a ... Gas passage 13 ... Puffer Cylinder 14 …… Puffer piston, 15 …… Puffer chamber 16 …… Operation rod, 19 …… Insulation support 20 …… Arc, 28 …… Movable side link 29 …… Insulation rod, 30 …… Fixed side link 30a …… Fixed Lever 30b, 30c …… Movable lever 30d …… Support part, 30e …… Support point

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoru Yanagisa 2-1-1, Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Pref., Toshiba Hamakawasaki Plant Co., Ltd. (56) Reference JP 63-181222 (JP, A) Actual Open Sho 59-109042 (JP, U) Actual Open Sho 54-179469 (JP, U)

Claims (1)

[Claims] 1. A pair of contacts are provided in a container in which an arc extinguishing medium such as SF6 gas is sealed, and a movable arc contactor and a puffer cylinder are connected to an operating rod, and the operating rod is driven through an insulator or the like. The puffer piston is supported by a container via an insulator so that it slides between the operating rod and the puffer cylinder, and a nozzle is attached to the front of the puffer cylinder to cover the movable arc contactor. A so-called double-motion puffer-type gas cutoff, in which the insulated rod is driven in the direction opposite to the movable part by the link provided on the rod, and the fixed side contact is supported at the end of the insulated rod opposite to the link. In this device, a second link is provided at the end portion of the insulating rod that supports the fixed side contactor, and the movable lever is supported by the movable lever by combining the fixed lever and the movable lever of this link. The movable arc contact facing the arc contact is moved in the same direction as the moving part in the initial stage of opening and in the opposite direction from the moving part in the middle of opening, and the movable energizing contact moves simultaneously with the moving part. A puffer-type gas circuit breaker characterized in that the opposing fixed energizing contacts are fixed to the container by an insulator.