JPH07105799A - Gas-blast circuit-breaker - Google Patents

Abstract

PURPOSE:To provide a puffer type gas-blast circuit-breaker which can shut a large current with small puffer capacity and small driving force. CONSTITUTION:A movable arc contactor 6 and an accelerating arc contactor 1, which can touch with or part from the movable arc contactor 6, are set face to face each other and connected mutually with a link system 13. A puffer piston 8 which can slide along the outer circumferential face of an operational rod 12 is supported and fixed in a container. A first insulating nozzle and a second insulating nozzle to compose a gas flow route 10 are installed in the puffer piston 8. A frange part 16 which can slide along the inner circumferential face of the second insulating nozzle 5 is formed in the operational rod 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a puffer type gas circuit breaker used in a substation or a switching station of a power system.

[0002]

2. Description of the Related Art In recent years, with the increase in voltage and capacity of power generation systems, the breaking capacity of circuit breakers used in substations and switching stations of power transmission systems has increased. In addition, as substations are being built in buildings under the ground due to difficulty in securing sites in urban areas, there are increasing demands for circuit breakers with large capacity, smaller size, and higher reliability.

In order to improve the reliability of the circuit breaker, it is important to reduce the number of parts and simplify the structure. To this end, it is necessary to reduce the number of circuit breakers by increasing the circuit breaking capacity per circuit breaker.

In the conventional transmission voltage system of 168 KV or more,
A puffer type gas circuit breaker is used for the purpose of improving the breaking capacity and reducing the size as described above. This puffer type gas circuit breaker has a fixed arc contactor and a movable arc contactor that can be freely contacted and separated from each other in a container of a circuit breaker filled with an arc extinguishing gas, and these fixed arc contactor and movable arc contactor. The arc generated is extinguished by blowing the arc extinguishing gas compressed in the puffer chamber arranged on the movable contact side. This puffer-type gas circuit breaker is particularly well used because it has a simple structure of the circuit breaker and has excellent insulation and arc extinguishing performance due to the enclosed SF6 gas.

By the way, in order to improve the arc extinguishing performance in the above puffer type gas circuit breaker, it is necessary to increase the opening speed of the arc contact. However, in order to increase the contact opening speed on the movable contact side, the driving force of the driving device must be increased, and the driving device becomes large.
The size of the entire device also increases, resulting in higher costs. On the other hand, in order to increase the contact opening speed without changing the driving force of the driving device, a link device for moving the fixed contact in the direction opposite to the moving direction of the movable contact is provided, and the effect of extinguishing the arc is provided. There is a puffer type gas circuit breaker that uses an enhanced dual motion mechanism.

The puffer type gas circuit breaker will be described with reference to FIG. In FIG. 3, the accelerating arc contactor 1 arranged to face the movable arc contactor 6 has a movable arc contactor 6.
FIG. 3 is a cross-sectional view of a puffer type gas circuit breaker moving in a direction opposite to the moving direction of FIG. In FIG. 3, reference numeral 12 is an operation rod having one end connected to a drive device (not shown) and the movable arc contactor 6 attached to the other end. A puffer cylinder 21 is fixed around the operation rod 6.
The puffer cylinder 21 forms a puffer chamber with the puffer piston 8 which is slidably arranged inside and is supported and fixed to the insulating cylinder 15. A plurality of drive insulating rods 3 are arranged on the outer periphery of the puffer cylinder 21 with a constant distance from the puffer cylinder 21. The end portion of the drive insulating rod 3 on the drive unit side is connected to the operation rod 12 via a link unit 13. The link device 13 includes a link 13a having a fulcrum 13d set to a predetermined link ratio, and a first rotatably connected to both ends of the link 13a.
It is composed of second connecting rods 13b and 13c. Link 13
The fulcrum 13d of a is rotatably supported by the link support member 14. Also, the first and second connecting rods 13b, 13
c is rotatably connected to the operating rod 12 and the drive insulating rod 3 at one end thereof. The link support member
14 is fixed to the insulating cylinder 15. On the other hand, a current-carrying cylinder 22 is attached to the end of the drive insulating rod 3 on the side opposite to the drive device, and the current-carrying cylinder 22 slides on the current-carrying portion 23a of the current-carrying conductor 23 supported and fixed on the opposite side of the drive device. It is arranged to be movable. The acceleration arm contactor 1 is provided on the central axis of the energizing cylinder 22 on the drive side, and the movable arc contactor 6 is provided.
And an accelerating contactor 2 for opening and closing. In addition,
In the closed state of FIG. 3, the movable contact 6 and the acceleration arc contact 1 are in contact with each other.

When a shutoff command is input to the puffer type gas circuit breaker in the closed state shown in FIG. 3, first, the operating rod 12 is driven rightward in FIG. The contact 6 moves to the right, and a blocking operation occurs between the contact 6 and the acceleration contact 2. On the other hand, as the operation rod 12 moves, a force is applied to the first connecting rod 13b connected to the operating rod 12 in the same direction, and the force is applied to one end of the link 13a connected to the first connecting rod 13b. To the right in the figure. In this case, since the fulcrum 13d of the link 13a is rotatably fixedly supported, this force becomes a moment force for rotating counterclockwise about the fulcrum 13d, and the link 13a rotates in the same direction. Therefore, the other end of the link 13a rotates leftward in the figure, and the second connecting rod 13c connected to the same part is rotated.
Moves to the left, and the drive insulating rod 3 connected to this moves to the left. The accelerating contactor 2 fixed to the drive insulating rod 3 is moved leftward to be separated from the movable contactor 6, and the contact is opened as shown in FIG. That is, the movable arc contactor 6 according to the operation of the operation rod 12.
Both the accelerating arc contact and the accelerating arc contact move in the breaking direction.

[0008]

However, in the puffer type gas circuit breaker for operating the accelerating contact as described above, since the movable contact moves together with the insulating nozzle,
The position at which the arc-extinguishing gas is blown onto the arc is limited to the region on the downstream side of the insulating nozzle facing the acceleration contact. Therefore, the exhaust of the hot gas generated when the arc is extinguished stays on the downstream side between the arc contacts, and it is difficult to recover the insulation on the downstream side. In order to effectively extinguish the arc in this state, it must be processed by the pressure in the puffer chamber, so the volume of the puffer chamber must be sufficiently large and the pressure for blowing the arc-extinguishing gas to extinguish the arc must be high. It is necessary to increase the volume of the puffer chamber and the drive device.
There is a problem that the gas circuit breaker, which is desired to be downsized, becomes large. An object of the present invention is to solve the above problems and to provide a puffer type gas circuit breaker capable of effectively breaking a large capacity with a small puffer capacity and a small driving force.

[0009]

To achieve the above object, the present invention provides a movable arc contactor and an accelerating arc contact capable of contacting and separating the movable arc contactor in a container in which an arc extinguishing gas is enclosed. In a gas circuit breaker in which the movable arc contactor and the movable arc contactor are connected to each other via a link mechanism, the movable arc contactor is provided at the tip of the operating rod. A puffer piston that is slidable with the outer peripheral surface of the puffer piston is supported and fixed in the container, and a gap serving as a gas flow path is formed on the acceleration arc contactor side of the puffer piston and on the inner peripheral side of the first insulating nozzle. A gas circuit breaker is provided in which a second insulating nozzle disposed via the second insulating nozzle is provided, and a flange portion slidable with the inner peripheral surface of the second insulating nozzle is formed on the operation rod. Further, there is provided a circuit breaker in which an exhaust hole is formed which communicates with the puffer chamber when the operation rod of the gas circuit breaker is in the closed state and communicates with the inside of the container at the end of the circuit break.

[0010]

With this structure, when the operating rod is moved during the shutoff operation, the flange portion begins to compress the gas in the puffer chamber formed by the puffer piston. On the other hand, the accelerating arc contact moves in the opposite direction to the movable arc contact due to the link mechanism. That is, the two arc contacts move in opposite directions to start breaking, and an arc is generated between the arc contacts. Then, the gas compressed in the puffer chamber is blown to this arc through the gas passage. The first insulating nozzle and the second insulating nozzle are fixed and this compressed gas is blown so as to divide the arc into two equal parts because both arc contacts move in opposite directions. Therefore, since only half of the hot gas acts on the downstream side of the nozzle, the insulation recovery characteristic on the downstream side of the nozzle can be improved.

Further, since the exhaust hole is formed in the operating rod, it becomes possible to guide the heat of the arc to the puffer chamber in the initial stage of shutting off and to improve the gas compression efficiency, and to pass the hot gas through the operating rod in the final stage of shutting off. It is possible to efficiently exhaust the gas into the container.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. The same parts as those in FIGS. 3 and 4 are designated by the same reference numerals and the description thereof will be omitted. Figure 1 shows the loading state,
FIG. 2 shows a cutoff state. Reference numeral 12 denotes an operation rod whose one end is connected to a drive device (not shown). The movable arc contact 6 is fixed to the tip of the operation rod 12, and a flange 16 is formed near the fixed portion. Also this operating rod
One end of the link device 13 is connected to the link device 12, and the link device 13
The fulcrum 13e of the insulating cylinder 15 is fixed in a container (not shown).
It is rotatably supported by a link support member 14 attached to. On the other hand, the other end of the link device 13 is connected to one end of a drive insulating rod 3 arranged substantially parallel to the operating rod 12. On the other end side of the drive insulating rod 3, an accelerating arc contactor 1 which is arranged coaxially with the movable arc contactor 6 and can be brought into contact with and separated from the movable arc contactor 6, and this accelerating arc contactor 1
The accelerating contactor 2 arranged around the is fixed. A current-carrying portion 2a is formed at the tip of the accelerating contactor 2, and the current-carrying portion 2a is in sliding contact with the peripheral surface of the current-carrying contactor 7 arranged facing the accelerating contactor 2 and serves as a current-carrying path at the time of closing. A puffer piston 8 that slides on the outer peripheral surface of the operating rod 12 is fixed to the inner peripheral side of the current-carrying contactor 7.
Is fixed to the insulating tube 15. A first insulating nozzle 4 is provided on the inner peripheral side of the current-carrying contact 7 and on the side of the acceleration arc contact 1 with respect to the puffer piston 8. The second insulating nozzle 5 that forms the gas flow path 10 is provided. A puffer chamber 9 is formed by the inner peripheral surface of the second insulating nozzle 5 and the flange portion 16 and the puffer piston 8 which slide on the inner peripheral surface.

Next, the operation will be described. In the closed state shown in FIG. 1, when the disconnection command is received and the opening operation starts, the drive rod moves the operation rod 12 to the drive side (rightward in the figure). When the operating rod 12 moves, the flange portion 16 formed on the operating rod 12 starts to compress the gas in the puffer chamber 9. On the other hand, the acceleration arc contactor 1 has a link mechanism.
The drive insulating rod 3 driven leftward in the figure by 13 moves to the left in the figure, separates from the movable arc contactor 1 that was in sliding contact, starts breaking, and an arc is generated between both arc contactors. The gas pressure in the puffer chamber 9 rises in this arc, and the compressed gas passes through the gas flow path 10,
It becomes a high-speed gas and is blown and cut off. Since the first insulating nozzle 4 and the second insulating nozzle 5 are fixed and the arc contacts 1 move in opposite directions, this blowing gas is blown so as to divide the arc into two equal parts during the breaking operation. That is, since the arc is divided into two at the stagnation point of the gas blown from the nozzle, the hot gas flow processed on the operating rod 12 side becomes almost equal to the hot gas amount processed on the nozzle downstream side, and the nozzle downstream side. The insulation recovery characteristics of are improved.

Therefore, even if the volume of the puffer chamber is reduced, it is possible to obtain the specified breaking performance, and it is possible to provide a highly reliable gas circuit breaker. In this example,
Further, the operating rod 12 is formed in a hollow shape, and the operating rod is
By forming an exhaust hole 11 which communicates with the puffer chamber 9 from the closed state to the middle stage of the shut-off and communicates with the container at the final stage of the shut-off at 12, the compression efficiency in the puffer chamber 9 is increased by utilizing the heat of the arc at the early stage of shut-off. Further, it is possible to efficiently discharge the gas exposed to the arc into the container in the latter half of the shutoff, and the puffer chamber can be further downsized.

[0015]

As described above, according to the present invention, the compressed gas blows off the arc from the gas flow passage formed between the first insulating nozzle and the second insulating nozzle so as to divide the arc into two equal parts. The hot gas generated during the arc is prevented from concentrating on the downstream side between the arc contacts, and the insulation recovery on the downstream side is facilitated. Further, by providing the exhaust hole in the operation rod, the compression efficiency in the puffer chamber in the initial stage of shutoff can be improved, the hot gas can be efficiently exhausted in the final stage of shutoff, and the insulating effect can be enhanced. Therefore, it is possible to provide a puffer-type gas circuit breaker that can effectively cut off a large capacity with a small puffer capacity and a small driving force.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a gas circuit breaker in a closed state according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the gas circuit breaker shown in FIG. 1 in a disconnected state.

FIG. 3 is a sectional view of a conventional gas circuit breaker in a closed state.

FIG. 4 is a sectional view of the gas circuit breaker shown in FIG. 3 in a shut-off state.

[Explanation of symbols]

1 ... Accelerating arc contactor, 3 ... Drive insulating rod, 4 ... First
Insulation nozzle, 5 ... Second insulation nozzle, 6 ... Movable arc contactor, 8 ... Piston, 9 ... Puffer chamber, 10 ... Gas flow path, 11
... Exhaust hole, 12 ... Operation rod, 13 ... Link device, 13a ... Link, 13b ... First connecting rod, 13c ... Second connecting rod, 13d
… Support point, 14… Link support member, 15… Insulation cylinder, 16… Flange part.

Claims (2)

[Claims] 1. A movable arc contactor and an accelerating arc contactor capable of coming into contact with and separating from the movable arc contactor are arranged to face each other in a container filled with an arc extinguishing gas. In a gas circuit breaker in which the accelerating arc contactor is connected via a link mechanism, the movable arc contactor is provided at the tip of an operating rod, and a puffer piston slidable with the outer peripheral surface of the operating rod is provided in the container. Supporting and fixing, a first insulating nozzle is provided on the side of the acceleration arc contact of the puffer piston, and a second insulating nozzle is provided on the inner peripheral side of the first insulating nozzle with a gap serving as a gas flow path, A gas circuit breaker characterized in that a flange portion slidable on the inner peripheral surface of the second insulating nozzle is formed on the operation rod. 2. The gas circuit breaker according to claim 1, wherein an exhaust hole is formed in the operating rod so as to communicate with the puffer chamber when in the closed state and communicate with the inside of the container at the final stage of shutoff.