JPS63148514A - 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 [Object of the Invention] (Industrial Application Field) The present invention relates to a gas circuit breaker in which an internal current transformer is housed in a circuit breaker tank.

(Prior Art) In recent years, there has been a remarkable increase in the high voltage and large capacity of power systems and the concentration of power demand in urban areas. For this reason, circuit breakers that protect the system from short-circuit accidents are required to be smaller in size to improve large current interrupting performance and to accommodate installation locations. On the other hand, currently the most suitable material is SFe.
This is a gas circuit breaker that uses gas as an insulating arc-extinguishing medium. Among these gas circuit breakers, buffer type gas circuit breakers have become mainstream as circuit breakers in the voltage class of 300KV to 500KV due to their excellent circuit breaking performance and high reliability due to their simple structure. Instead, by adopting a three-phase finger-shaped structure, it is possible to further reduce the size of the circuit breaker in the voltage class of 10 to 300 KV.

However, with the recent development of urban areas and the lack of land and rising land prices, there is a desire for substations to be further downsized, as well as higher voltage and larger capacity. In view of these problems, a gas circuit breaker has been devised in which a current transformer is housed in the tank of the gas circuit breaker in the cylindrical axial direction of the tank and in the same energizing direction as the circuit breaker's circuit breaker.

However, in such a buffer type gas circuit breaker,
Since the cut-off parts for each phase are placed close to each other in the same tank, there is a risk that the high-temperature exhaust gas after the arc is extinguished will cause dielectric breakdown between the phases after the current is cut off, or that a ground fault will occur between the cut-off part and the tank. there were. To prevent this, some models increase the distance between the phases or between each phase and the tank, or install an insulating tube surrounding the fixed side member and the movable side member, but the former increases the tank diameter and makes it difficult to downsize. However, the latter had the disadvantage of poor exhaust gas, resulting in a decrease in shutoff performance.

Therefore, as a structure that does not have such drawbacks,
According to Japanese Patent No. 087035, a structure is considered in which the blowing direction of hot gas is directed away from the inner wall of the tank. Its structure is shown in FIG.

The tank 1 is filled with an arc-extinguishing gas 2, for example, SFa gas, and contains three-phase cut-off parts 3.

This cut-off part 3 is arranged in the cylindrical axis direction of the tank 1, and a current transformer 4 is attached on an extension line of the cut-off part 3. A cylindrical conductor 6 for electrical connection is provided to pass through. A shield 7 is attached to the outer periphery of the base end of this cylindrical conductor 6 to alleviate the surrounding electric field, and a current collector 8 is arranged on the inner periphery as shown in FIG. A contact conductor 9 is attached to the current collector 8, and the cutoff portion 3 and the cylindrical conductor 6 are connected via the contact conductor 9. Further, the tip of the cylindrical conductor 6 is connected to an outlet conductor 11 via a conductor 10.

On the other hand, the cutoff section 3 is composed of a fixed electrode section 12 and a movable electrode section 13, the fixed electrode section 12 is communicated with the movable electrode section 13 through an insulating tube 14, and the base end of the movable electrode section 13 is connected to a movable connection section. It is connected to the lead conductor 16 and the drive mechanism section 17 via 15.

The fixed electrode section 12 and the movable electrode section 13 are constructed as shown in FIG. 7. That is, the fixed electrode section 12
It has a cylindrical shape with a flange at the center of its outer periphery, an opening 12a formed in the center of the head and a side surface above the flange, and a fixed current-carrying contact 18 is provided at the tip. A fixed arc contact 19 is disposed at the center of the fixed current-carrying contact 18, and is attached to the inside of the fixed electrode part 12 by a fixed plate 20 having an opening 20a.A space 21 is provided behind the fixed plate 20. It is formed.

The movable electrode section 12 also includes a buffer cylinder 22 connected to the drive mechanism section 17 via an operation rod (not shown).
A buffer ash chamber 24 is formed by the pants 1 piston 23 and the pants 1 piston 23. Roughly speaking, at the tip of the buffer cylinder 22, there is provided a movable arc contact 25 in contact with the fixed arc contact 18, and an insulating nozzle 26 surrounding the movable arc contact 25. A movable current-carrying contact 27 is provided.

When a disconnection command is given to the circuit breaker having such a configuration, the drive mechanism section 17 is activated and the operation rod (not shown) is driven in the X direction, so that the buffer cylinder 22 attached to the operation rod is also Driven in the X direction, the fixed arc contact 18 and the movable arc contact 24 are separated,
An arc occurs between both arcing contacts 18.25. This arc is interrupted at the current zero point by introducing compressed gas A1 from the buffer chamber 24 between the arc electrodes through an insulating nozzle 25 and spraying it onto the arc. The gas A2 blown to the arc becomes hot gas A3 due to arc heat and flows into the space 20 of the fixed electrode section 12, and the hot gas is discharged to the outside space of the fixed electrode section 12 through the rough opening 12a.

The arc generated between both arc contacts 18 and 25 as described above is caused by the compressed gas A1 sent out from the buffer chamber. A
By extinguishing the arc by 2, the withstand voltage performance to the ground and between phases can be improved, and it is possible to prevent ground faults and short circuits between phases due to recovery voltage.

(Problems to be Solved by the Invention) Nowadays, as mentioned above, there is a demand for smaller circuit breakers and higher voltage and larger capacity. However, in the conventional circuit breakers shown in FIGS. 6 and 7, when the size is roughly reduced and the high voltage and capacity are increased, the hot gas after the compressed gas is blown onto the arc flows through the opening 12a. A large amount of hot gas leaked out, and the large amount of hot gas that leaked out caused dielectric breakdown between the phases and to the ground, potentially causing a ground fault to the grounding section. Such problems occur not only in the illustrated three-phase gas circuit breaker, but also in single-phase gas circuit breakers.

An object of the present invention is to provide a small, high-voltage, large-capacity gas circuit breaker that eliminates the drawbacks of conventional circuit breakers as described above, does not cause dielectric breakdown between each phase and to the ground, and has excellent interrupting performance. It is in.

[Structure of the Invention] (Means for Solving the Problems) The gas circuit breaker of the present invention includes: a head of a space inside a fixed electrode part of a cutoff part, a connecting conductor connecting the cutoff part and a cylindrical conductor, and a current transformer. By providing an opening in each of the cylindrical conductors penetrating the inner circumference of the cylindrical conductor, the cylindrical conductor and the space on the opposite side of the blocking part are connected via the space inside the fixed part.

(Function) In the gas circuit breaker of the present invention, in addition to the space conventionally provided in the fixed part interior space, openings are provided in the space head, the connecting conductor, the cylindrical conductor, and the outlet conductor in the interrupting part. After extinguishing the arc, part of the hot gas is led into the external space of the fixed electrode part, and the rest is led out through the cylindrical conductor and into the upper space inside the tank from the cylindrical conductor and the opening of the conductor.

(Example) Next, an example in which the present invention is applied to a three-phase collective gas circuit breaker will be described with reference to FIGS. 1 to 3.

Note that the same parts as those in the prior art are given the same reference numerals and the description thereof will be omitted.

Configuration of this embodiment * In Figures 1 and 2, an opening 2 is provided at the head of the fixed electrode section.
8 is formed, and an opening 29 is provided through the connecting conductor 9 so as to correspond to this opening 28 . Roughly,
An opening 30 is formed on the upper side surface of the cylindrical conductor 6, and an opening 31 is provided in the conductor 10 corresponding to the head opening of the cylindrical conductor 6. Opening 31 of this conductor 10
is curved.

Note that the axis of the opening 30 in which the cylindrical conductor 6 is formed is
As shown in FIG. 3, it is more effective to configure the grounded tanks so that they are not perpendicular to each other and the axes of the three phases in the opening direction do not intersect.

Effect of this embodiment * In the gas circuit breaker of this embodiment configured as described above, when a cutoff command is given to the circuit breaker, the fixed arc contact 18 and the movable arc contact 25 are separated, and both arc contacts 18.2
5, the compressed gas sent out from the buffer chamber 24 is guided as Al-A2, and is blown onto the arc, and the arc is extinguished. At the same time, the compressed gas A2 becomes hot gas A3 and is fixed. It flows into the space 20 of the electrode section 12 . A portion of this hot gas A3 is discharged from the opening 12a to the outside space of the fixed electrode section 12, and the remaining hot gas passes through the opening 29 of the connecting conductor 9 from the head opening 28 of the fixed electrode section 12, and the remaining hot gas A4
→ A5 → A6, the liquid is discharged into the upper space of the tank 1 through the openings 30 and 31 of the cylindrical conductor 6.

Effect of this embodiment
By providing 0.31, the hot gas A3 is not exhausted only from the opening 12a of the fixed electrode section 12 formed conventionally, but some of the hot gas is exhausted from the opening 12a. Since the remaining hot gas is separated and discharged through the openings 30 and 31, the withstand voltage performance around the fixed electrode section 12 is improved by reducing the amount of hot gas discharged from the opening 12a. It is possible to prevent a ground fault to the flow vessel 14 and the grounded tank 1, and by discharging the hot gas to the upper part, the efficiency of discharging the hot gas is increased, so that the size can be reduced to accommodate more people.

*Other Examples* In the above example, the opening provided in the conductor 10 was formed in a curved manner to prevent direct discharge to the inner wall of the tank.
It does not necessarily have to be provided on gray hair.

Further, in the embodiment shown in FIG. 4, the space 20 of the fixed electrode section 12 is eliminated, and the fixed electrode section 32 has a fixed arc contact 19 and a fixed current-carrying contact 18 supported on a support plate 33, and a coexisting contactor 18. An opening 34 is formed between the openings 19 and 19 . A cylindrical fixed contact 35 with a wide tip is connected to the fixed electrode portion 32 .

On the other hand, the tip of the cylindrical conductor 36 provided through the current transformer 4 is formed into a trumpet shape larger than the diameter of the cylindrical conductor 36. 8 are arranged. The base end of the fixed contact 35 is connected to the current collector 8, and the cutoff portion 3 and the trumpet-shaped cylindrical conductor 36 are communicated with each other. Note that openings 30 and 31 are provided above the trumpet-shaped cylindrical conductor 36 and in the conductor 10, as in this embodiment.

In the gas circuit breaker of the embodiment shown in FIG. Since no leakage occurs, ground faults can be prevented, and since the distance between the shield 7 and the fixed electrode section 12 is shortened, the surrounding electric field can be further alleviated.

In addition, by directly discharging the hot gas from the cylindrical conductor 36 after passing through the current transformer 4, dielectric breakdown between each phase can be prevented, and the hot gas can be discharged in the same direction as the compressed gas blowing direction. It increases the discharge efficiency and is made smaller considering the insulation performance after shutoff.

Roughly speaking, as shown in FIG. 5, even if the cylindrical conductor 6 has only 30 openings, its role is sufficient.

[Effects of the Invention] As described above, according to the present invention, a cylindrical conductor that sandwiches the fixed electrode space and the current transformer and penetrates the inner periphery of the current transformer with an opening provided in the space opposite to the cutoff part. By forming an opening above the cylindrical conductor, the hot gas generated when the current is cut off is dispersed and discharged, and a large amount of hot gas is not discharged into the space around the fixed electrode. In addition, hot gas is not discharged to nearby conductors, and the blowing direction between each phase can be guided into a wide space, so there is no dielectric breakdown between each phase or to the ground, and this is a small, high voltage, large capacity gas cutoff with excellent breaking performance. Equipment can be provided.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of one phase in an embodiment in which the present invention is applied to a three-phase gas circuit breaker, FIG. 2 is a sectional view of the gas circuit breaker of the embodiment shown in FIG. XX sectional view, FIG. 4 and FIG. 5 are sectional views for one phase showing other embodiments of the gas circuit breaker of the present invention, and FIG. 6 is a sectional view for three phases of a conventional gas circuit breaker. FIG. 7 is a cross-sectional view of one phase of the gas circuit breaker shown in FIG. DESCRIPTION OF SYMBOLS 1... Tank, 2... Arc-extinguishing gas, 3... Shutoff part, 4... Current transformer, 5, 10... Conductor, 6, 36...
・Cylindrical conductor, 7... Shield, 8... Current collector, 9
. . . Connection conductor, 11. 16 . . . Output conductor, 12.
32...Fixed electrode part, 12a...Opening part, 13...
- Movable electrode part, 14... Insulating tube, 15... Movable contact part, 17... Drive mechanism part, 18... Fixed energizing contact, 19... Fixed "arc contact", 20...・Fixing plate,
20a...Opening, 21...Space, 22...Buffer cylinder, 23...Buffer piston, 24...
・Buffer 1 chamber, 25... Movable arc contactor, 26...
・Insulating nozzle, 27...Movable current-carrying contact, 28゜29
．． 30, 31. 34... Opening, 33... Support plate,
35... Fixed contact.

Claims (2)

[Claims] (1) The interrupting part of the circuit breaker is housed in a tank filled with insulating gas, and a current transformer is installed on the extension of the interrupting part so that the current direction matches the axial direction of the tank cylinder, and each phase In a gas circuit breaker in which a connecting conductor connects the breaking part of the current transformer with a cylindrical conductor penetrating the inner periphery of the current transformer, a hollow fixed electrode part is provided in the breaking part of each phase, and the fixed electrode head and the above-mentioned Openings are formed in each of the connecting conductor and the cylindrical conductor, and the inside of the hollow fixed electrode communicates with the space on the opposite side of the cutoff part across the current transformer through each of the openings. Characteristic gas circuit breaker. (2) Shutoff parts for three phases are housed in the tank, and the opening that communicates with the space on the opposite side of the cutoff part provided in the cylindrical conductor of the cutoff part for each phase has an axis line that is perpendicular to the grounded tank. 2. The gas circuit breaker according to claim 1, wherein the axes of the openings between the three phases do not intersect.