JPH03238724A - Buffer-type gas shut off device - Google Patents

Abstract

PURPOSE:To make proximity arrangement possible to scale down the whole of a gas shut off device by surrounding the shut-off contactor parts and the resistance contact parts on the movable side and the fixed side by means of the same shields, respectively, supporting and fixing the shields to the resistance contactor parts on the movable side and the fixed side and equalizing the potential of the shield to that of the resistance contact part. CONSTITUTION:A resistance contactor part 24 having making-resistance is arranged approximately in mechanically parallel with and electrically parallel to a shut-off contact part 21, and a movable side shield 31 and a fixed side shielding 32 are arranged respectively on the circumference across the movable side contactor part 2' of a shut- off contactor part 21 and the movable side resistance contactor part 26 of the resistance contactor part 24 and across the fixed side contactor part 1' of a shut-off contactor part 21 and the fixed side resistance contactor part 27 of the resistance contactor part 24. Then, the potential of this movable side shield 31 is set to the potential same as that of the movable side resistance contactor part 26, and the potential of the movable side shield 32 is set to the potential same as that of the fixed side resistance contactor part 27. It is thereby possible to set the distance between the shut-off contactor part 21 and the resistance contactor part 24 to the required minimum so that the arc-extinguishing chamber can be made totally small.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a puffer type gas circuit breaker used in a substation or switchyard of a power system.

(Prior Art) In recent years, as the capacity of power transmission systems has increased, the breaking capacity of circuit breakers used in substations and switchyards has increased. Therefore,
Circuit breakers are required to have high reliability, and efforts are being made to reduce the number of parts and simplify the structure.

For example, in a puffer type gas circuit breaker, compressed gas is created in the puffer chamber by the gas compression action of a puffer cylinder directly connected to a movable contact and a fixed puffer piston, and this gas is guided to a nozzle to create a high-speed gas flow. The arc is cooled and extinguished by spraying this high-speed gas flow onto the arc. Therefore, the puffer-type slag circuit breaker can store high-pressure gas in advance, and there is no need to open or close a valve when blowing a gas stream against an arc, so the structure is simple and has high reliability. can. Furthermore, in the puffer type gas circuit breaker, high blowing pressure can be obtained due to the self-pressurizing effect of the arc, so the circuit breaker performance is also improved. Such puffer type gas circuit breakers have become the mainstream of high voltage circuit breakers of 72 kV or higher due to their excellent characteristics as described in 1.

By the way, the breaking performance per breaking point of such puffer-type gas circuit breakers has been improved due to technological progress, and in recent years 42
Although the current voltage has reached 0 kV, the inexpensive puffer type gas circuit breaker described in JP-A-61-193321 has been proposed as a method for increasing the voltage per one breaking point. The second puffer type gas circuit breaker is generally referred to as a double-motion system, which moves a movable contact and at the same time moves the contact opposite to this movable contact to increase the insulation recovery voltage during breaking operation. It is something that

That is, FIG. 4 shows an example of such a double motion type puffer type gas circuit breaker.
The movable contact section 1 is composed of a first movable arc contact 1a, a first movable energizing contact 1b, and a nozzle 1c.

The first movable contact portion 1 is fixed to the tip of the operating rod 3 together with the puffer cylinder 4 . Operation rod 3
An operating mechanism (not shown) is connected to the base via an insulating rod 9, and the first movable contact portion 1 and the puffer cylinder 4 are moved together with the operating rod 3 in the opening/closing direction by the driving force of the operating mechanism. It is.

Furthermore, a fixed puffer piston 5 is slidably incorporated inside the puffer cylinder 4, and the base portion (operating mechanism side) of the puffer piston 5 is fixed to the insulating cylinder 1.6 via the nozzle holder 14. ing. As a result, a puffer chamber 10 is formed between the puffer cylinder 4 and the second puffer piston 5, and this puffer chamber 10 and the nozzle 1
It communicates with c.

On the other hand, the second movable contact section 2 is arranged opposite to the first movable contact section 1, and is composed of a second movable arc contact 2a, a second movable energizing contact 2b, and a second movable shield 2c. has been done. A movable current-carrying contact 7 is integrally provided at the base of the second movable contact section 2 (on the opposite side to the first movable contact section 1), and is supported in an insulated state by the case of the circuit breaker. It is in slidable contact with the current-carrying contact 8 on the fixed side.

The second movable contact section 2 is arranged parallel to the operating rod 3 on the outer periphery of each movable contact section 1.
It is directly connected to a plurality of insulating rods 15 extending toward the base side. This insulating rod 15 is connected to a link mechanism section 6 connected to the base of the operating rod 3. This link mechanism section 6 includes a pin 6a fixed to the nozzle 14, a link 6b pivotally connected to this pin 6a, and this link 6b.
It is composed of joints 6c and 6d that connect to the operating rod 3 and the insulating rod 15. By means of this link mechanism section 6, during the breaking and closing operations, the second movable contact section 2 is moved in the opposite direction to the first movable contact section 1 by the driving force from the insulating rod 9 connected to the operating rod 3. It is configured to be driven by.

Next, the operation of the conventional puffer type gas circuit breaker having such a configuration will be explained. First, FIG. 4 shows the circuit breaker in an open state. In this state, an opening force is applied to the puffer cylinder 4 via the insulating rod 9 from an operating mechanism (not shown).
and is transmitted to the first movable contact portion 1, the puffer cylinder 4 and the first movable contact portion 1 are driven in the direction of the arrow 17, whereas the link mechanism portion 6 and the insulating rod 1 are driven in the direction of the arrow 17.
5, the second movable contact part 2 is driven in the direction of the arrow 18.

Therefore, compressed gas is created within the puffer cylinder 4 and is blown out from the nozzle 1a as a high-speed gas flow. Due to this high-speed gas flow, the movable arc contact IC and the arc contact 2
The arc generated between points a is cooled and extinguished. During such a contact opening operation, as mentioned above, the second movable contact section 2 is driven in the opposite direction to the first movable contact section 1, so that a large gap can be provided during disconnection, and high insulation recovery performance can be achieved. Obtainable.

(Problem to be solved by the invention) By the way, in high voltage circuit breakers exceeding 300 kV,
In order to suppress the high surge voltage at the time of closing, a resistance contact section is installed electrically in parallel with the breaking contact section.When the circuit breaker is closed, the resistance contact section is first turned on, and the closing current is transferred to the resistance contact section. Generally, a puffer-type gas circuit breaker is adopted, which is a resistor closing method in which the current flows through a closing resistor connected to a closing resistor, and then the breaking contact is closed.

This resistance contact section is normally driven via a resistance contact link connected to the operation rod of the cutoff contact section, so it can be used in a double mosine type puffer type gas circuit breaker as shown in Fig. 4. When installing the resistance contact section, in addition to the link mechanism for the double motion system, the resistance contact section and its drive mechanism are required, which poses the problem of increasing the size of the entire device.

On the other hand, in order to miniaturize the device, it is necessary to make the distance between the cut-off contact and the resistance contact as close as possible, but considering the dielectric breakdown caused by the potential difference between these contacts when turning on. , it is impossible to simply arrange these contactor parts in close proximity. In other words, in a resistance closing type circuit breaker, when the circuit breaker is closed, the resistance contact part is brought into contact before the breaking contact part, so that the making current flows through the resistance part first, and then the breaking contact part is brought into contact. Since current is flowing through the breaking contact side, there is a potential difference between the solid contacts due to the resistance and the current flowing through it, although it is a short time from when the resistance contact comes into contact until when the breaking contact comes into contact. occurs. At this time, if the disconnection contact part and the resistance contact part are simply placed close to each other in order to downsize the puffer type gas circuit breaker, there is a risk that dielectric breakdown will occur between them.

In a puffer type gas circuit breaker equipped with a resistance contact as described above, it is impossible to simply place the resistance contact and the breaking contact in close proximity, and each mechanism necessary for double motion Due to the existence of a resistive contact section that is difficult to arrange, it has been extremely difficult to miniaturize a double-motion type puffer-colored gas circuit breaker that uses a resistive contact section.

In addition, the problem of dielectric breakdown due to the potential difference between the resistance contact part and the breaking contact part does not only occur in the double-motion puffer type gas circuit breakers mentioned above.
Even in so-called single-motion puffer-type gas circuit breakers in which only the movable contact on the operating rod side performs the opening action relative to the fixed contact, the circuit breaker is constructed by arranging the resistance contact part and the breaking contact part close to each other. A similar problem occurs when trying to downsize a device.

The present invention has been made in order to solve the problems of the prior art as described in 1.The purpose of the present invention is to provide a puffer-type gas circuit breaker having a resistive contact part and a breaking contact between the resistive contact part and the breaking contact. The present invention provides a puffer-type gas circuit breaker that can contribute to miniaturization of the circuit breaker as a whole by allowing child parts to be placed close to each other without causing dielectric breakdown.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the invention according to claim 1 of the present application provides an interrupting contact consisting of a movable contact portion and a fixed contact portion. In a single-motion type puffer type gas circuit breaker having a child part, the movable side breaking contact part and the movable side resistance contact part, and the fixed side breaking contact part and the fixed side resistance contact part are each shielded with the same shield. At the same time, each shield is supported and fixed to the movable-side and fixed-side resistance contact portions, respectively, and is configured to have the same potential as the respective resistance contact portions.

Further, the invention according to claim 2 of the present application provides the rigid double motion type puffer type gas circuit breaker illustrated in FIG. The second movable breaking contact part and the second movable resistance contact part are each surrounded by the same shield, and at the same time, each shield is supported and fixed to the first and second movable resistance contact part, and each resistance contact part is surrounded by the same shield. It is configured to have the same potential as the child.

(Function) According to the puffer type gas circuit breaker of the present invention having the above-described structure, when the circuit breaker is turned on, the resistive contactor part contacts from the time when the resistive contactor part contacts until the breaking contactor part contacts. Even if a potential difference occurs between the breaking contact part and the resistive contact part due to the resistor connected to the resistor, the electric field applied to the breaking contact part is alleviated by the trough which is configured to have the same potential as the resistive contact part. Therefore, it is possible to obtain interrupting performance without causing dielectric breakdown between the interrupting contact portion and the resistance contact portion.

As a result, it is possible to minimize the short distance between the cut-off contact part and the resistance contact part, making it possible to provide a puffer-type gas circuit breaker in which the overall diameter of the arc extinguishing chamber is minimized. It is possible.

(Example) Hereinafter, an example of the present invention will be specifically described with reference to FIGS. 1 to 3. Note that this example is based on claim 1 of the present application.
The present invention is applied to a single-motion puffer type gas circuit breaker.

In this embodiment, a breaking contact portion 21 is provided in a container 20 filled with an arc-extinguishing gas on a shaft that is slightly eccentric with respect to the central axis of the container. The cutoff contact section 21 includes a movable contact section 1'' driven by the operating rod 3, and a stationary contact section 2 fixedly supported with respect to the nozzle holder 14 via an interpolar insulating tube 22. ′.

On the other hand, a resistance contact part 24 having a closing resistor 23 is provided between the cutoff contact part 21 and the hair line.

In this case, the distance between the cutoff contact part 21 and the resistance contact part 24 is set to the minimum insulation distance that can withstand the potential difference caused by the current flowing to the resistance contact side at the time of turning on, while taking into account the effects of each shield described later. has been done. This resistance contact part 24 includes a movable resistance contact 26 connected to the operating rod 3 or driven by a link 25, and a fixed resistance contact which is always urged toward the movable resistance contact 26 by a spring 27. child 28. These movable resistance contacts 2
A movable resistance contact shield 29 and a fixed resistance contact shield 30 are provided on the outer periphery of the fixed resistance contact 6 and the fixed resistance contact 28, respectively.

Further, a movable shield 31 is provided on the outer periphery of the movable contact portion 1 ′ of the breaking contact portion 21 and the movable resistance contact portion 26 of the resistance contact portion 24 , and a movable side shield 31 is provided on the outer periphery of the movable side contact portion 1 ′ of the breaking contact portion 21 and the movable side resistance contact portion 26 of the resistance contact portion 24 . A fixed side shield 32 is provided on the outer periphery of the fixed side resistance contact 28 of the resistance contact portion 2' and the resistance contact portion 24. Here, the movable resistance contact 26 and the movable resistance contact shield 29 are connected to have the same potential as the movable shield 31,
Fixed side resistance contact 28 and fixed side resistance contact shield 30
are also connected to have the same potential as the fixed side shield 32. In addition, in FIG. 3, a movable side shield 31 and a fixed side shield 3 are attached to the cutoff contact part 21 and the resistance contact part 24.
2 is connected.

The operation of this embodiment having the above configuration will be explained. As shown in Figure 1, when a cutoff command is received in the closed state,
When the electrode opening operation begins, the insulating rod 9 moves in the direction of a drive device (not shown).

When the insulating rod 9 operates, the puffer cylinder 4 attached to the insulating rod 9 via the operating rod 3 moves in the same direction as the insulating rod 9, and accordingly, the puffer cylinder 4 and the puffer piston 5 are The compressed puffer chamber 1o begins to be compressed. Simultaneously with this opening operation of the puffer cylinder 4, the movable arc contact 1a, which is integrally fixed to the puffer cylinder 4, moves the fixed arc contact 2a.
The arc contacts 1a and 2a are separated, and an arc 11 is generated between the arc contacts 1a and 2a. The gas pressure in the puffer chamber 10 increases due to the mechanical rise due to the compression of the puffer chamber 1o and the heat of the arc 11 as well as the opening operation, and is blown onto the arc 11 from the nozzle IC communicating with the puffer chamber 10 to extinguish it. arc

On the other hand, as the insulating rod 9 moves, the movable resistance contact 26 connected to the insulating rod 9 via the link 25 also opens.
Since the current is configured to open earlier than the opening operation of the resistive contact section 21, the current flows only to the interrupting contact section 21, and the current is not interrupted at the resistance contact section 24. Therefore, the resistance contact part 2
Since no current flows through the resistor 23 connected in series with 4,
A potential difference occurs between the movable resistive contactor shield 29 and the movable shield 31 (7).Also, when the breaking contact portion 21 is opened, the gap between the resistive contact 1 portion 24 increases by 1 minute, and the resistive contactor The possibility of dielectric breakdown occurring in the portion 24 is extremely low.

On the other hand, in the closing operation, an operation opposite to the breaking operation is performed, but since the resistance contact portion 24 comes into contact earlier than the breaking contact portion 21 with the P-L no-arc or the like, the current flows to the resistance contact portion 24 side. flows. This current and resistance create a potential difference between the resistance contact section 24 and the cutoff contact section 21. This potential difference occurs for a short period of time until the cutoff contact portion 21 comes into contact. However, according to this embodiment, when the resistance contact section 24 is turned on, the movable resistance contact shield 29 and the fixed resistance contact shield 30 have an electric field relaxation effect on the breaking contact section 21. be able to.

Moreover, the movable side shield 31 and the fixed side shield 32 are
Since it is connected to the movable resistance contact 26 or the fixed resistance contact 28 and has the same potential as those of these resistance contact parts 24, it is possible to further enhance the electric field relaxation effect of the resistance contact part 24. At the same time, the distance between the movable side shield 31 and the movable resistance contactor shield 29 and the fixed side silt 32
It is possible to bring the distance between the fixed resistance contactor shield 30 and the fixed resistance contactor shield 30 close to each other until they are in contact with each other.

Therefore, it is possible to minimize the distance between the cutoff contact part 21 and the resistance contact part 24, and the movable shield 3
1 and the fixed side shield 32 can be made smaller, and accordingly, the diameter of the tank 20 can be made smaller.

(Other Embodiments) When the present invention is applied to a double-motion puffer type gas circuit breaker as claimed in claim 2, the movable side of FIGS. In place of the contact section 1' and the stationary contact section 2', the contact section 1.1 shown in FIG.
The second movable contact part 2 is constructed by using the movable contact part 1 and the second movable contact part 2, and by movably supporting the second movable contact part 2 with respect to the interpolar insulating cylinder 22. Link 6
and is connected to the operating rod 3 via an insulating rod 15, so that the first movable contact portion 1 and the second movable contact portion 2 move in opposite directions when the contact is opened.

Also, in the resistance contact section 24, the two resistance contacts, which were called the movable resistance contact and the fixed resistance contact in the above embodiment, become a first movable resistance contact and a second movable resistance contact. , the movable side shield 31 and the fixed side shield 32 arranged around these constitute a first movable side shield and a second movable side shield.

Furthermore, in order to reduce the diameter of the circuit breaker container 20, the link 6
The insulating rod] 5 is arranged at a position perpendicular to the line connecting the breaking contact section 21 and the resistance contact section 24 (on the front side or the back side of the breaking contact section 21 in the figure).

[Effects of the Invention] As described above, according to the present invention, the movable contact (or first movable contact) and the fixed contact (or 2nd movable contact)
By housing them in the same shield and making each shield the same potential as the resistive contact on each side, it is possible to satisfy the specified electric field strength with a shield with a smaller diameter than before. can do. Therefore, it is possible to minimize the distance between the cut-off contact and the resistance contact to prevent damage due to the potential difference between the resistance contact and the resistance contact that occurs when the switch is turned on, making the arc extinguishing chamber smaller overall. It is possible to provide a small puffer type gas circuit breaker.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the closed state of an embodiment in which the present invention is applied to a single-motion type puffer type gas circuit breaker;
Fig. 2 is a sectional view showing the puffer type gas circuit breaker in Fig. 1 during the breaking operation, Fig. 3 is a wiring diagram of the arc extinguishing chamber of the puffer type gas circuit breaker shown in Fig. 1, and Fig. 4 is a conventional FIG. 3 is a sectional view of the arc extinguishing chamber of the circuit breaker. DESCRIPTION OF SYMBOLS 1... First movable contact part, 1'... Fixed side contact part, 2... Second movable contact part, 2-... Movable side contact part, 3... Operation rod , 4... puffer cylinder,
5... Puffer piston, 6... Link mechanism, 7,
8... Current-carrying contact, 9... Insulating rod, 10...
Puffer chamber, 11... Arc, 14... Nozzle stand, 16
... Insulating tube, 17°18... Arrow, 20... Container, 21... Breaking contact portion, 22... Interelectrode insulating tube, 2
3... Closing resistance, 24... Resistance contact part, 25...
- Resistance contact side link, 26... Movable resistance contact, 27... Fixed side resistance contact, 28... Spring, 29
...Movable side resistance contactor shield, 30...Fixed side resistance contactor shield, 31...Movable side shield, 32.
・Fixed side seal F.

Claims (2)

[Claims] (1) In a single-motion puffer type gas circuit breaker in which a movable side contact portion and a fixed side contact portion are housed in a container filled with arc-extinguishing gas, the arc-extinguishing gas is placed approximately parallel to the breaking contact portion. Further, a resistance contact portion having a closing resistance is arranged electrically in parallel, and the movable side contact portion of the breaking contact portion, the movable side resistance contact portion of the resistance contact portion, and the fixing of the breaking contact portion are fixed. A movable side shield and a fixed side shield are arranged around the fixed side resistance contactor part of the side contactor and the resistance contactor part, respectively, and the movable side shield is fixed at the same potential as the movable side resistance contactor part. A puffer type gas circuit breaker characterized in that the side shield is configured to have the same potential as the fixed side resistance contact portion. (2) A breaking contact consisting of a first movable contact portion and a second movable contact portion that is driven in the opposite direction to the first movable contact portion in a container filled with arc-extinguishing gas. In a double-motion puffer-type gas circuit breaker that houses a child part, a resistive contact part having a closing resistance is arranged substantially parallel to and electrically in parallel with the breaking contact part, and the breaking contact part The periphery of the first movable contact part of the first movable contact part and the first movable resistance contact part of the resistance contact part, and the second movable contact part of the cutoff contact part and the second movable resistance contact part of the resistance contact part. a first movable side shield and a second movable side shield are respectively disposed in
A puffer type characterized in that the first movable side shield is configured to have the same potential as the first movable resistive contact portion, and the second movable side shield is configured to have the same potential as the second movable resistive contact portion. Gas circuit breaker.