JPH077625B2 - Puffer type gas pipe and disconnector - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a puffer type gas circuit breaker, and more particularly to a puffer type gas circuit breaker in which the material of the operating rod is improved.

[Technical background of the invention and its problems] High-pressure gas circuit breakers that blow an arc-extinguishing gas such as SF ₆ gas onto an arc are widely used because they easily withstand high voltage. Above all, a puffer type gas circuit breaker, which compresses an arc-extinguishing gas by utilizing a driving force at the time of contact dissociation and blows the compressed gas to an arc, is a mainstream of a high-voltage circuit breaker because of its simple structure.

In such a puffer type gas circuit breaker, in recent years, the cut-off capacity has been increasing along with the increase of the short-circuit capacity due to the increase of the transmission capacity. On the other hand, in order to downsize the equipment, the breaking capacity per point is increased and the number of series breaking points of the breaker is reduced. For this reason, as the breaking performance of the breaker, it is required to design the electric field between the poles of the breaker and to optimize the gas blowing mechanism.

FIG. 3 shows the structure of a puffer type gas circuit breaker which has been conventionally used. That is, inside the grounded container 1, together with the insulating gas 2 having excellent arc extinguishing property such as SF ₆ gas,
The circuit breaker 3 is stored. As the container 1, not only the grounded metal tank as shown in the drawing but also an insulator is used. Further, the cut-off portion 3 is not limited to one, but a plurality of cut-off portions may be electrically connected in series.

The cutoff portion 3 is composed of a fixed electrode portion 4, a movable electrode portion 5 arranged so as to come in contact with and separated from the fixed electrode portion 4, and a puffer portion 6 provided in contact with the movable electrode portion 5. The fixed electrode portion 4 is led out to the lead-out portion 7 via the conductor 8, and the conductor 8 is airtightly supported by the insulating spacer 9 provided in the lead-out portion 7. On the other hand, the puffer portion 6 disposed in contact with the movable electrode portion 5 is supported by the center piece or the supporting member 10 via an insulating member (not shown), and the contactor
It is electrically connected to the support member 10 via 11 and is electrically connected in series to a not-shown interrupting portion, or is led to the outside via a conductor not shown. Further, a cylindrical insulating member 12 is arranged so as to cover the fixed electrode portion 4 and the movable electrode portion 5.

The detailed structure of the cut-off portion 3 is shown in FIG. That is, in the fixed electrode portion 4, the fixed arc electrode 14 is fixed to the fixed electrode mounting member 13. On the other hand, the movable electrode portion 5 is provided on the end surface of the puffer portion 6 on the fixed electrode side of the puffer cylinder 15,
A cylindrical movable arc electrode 16 is provided, and an insulating nozzle 18 is fixed to the end surface of the puffer cylinder 15 by a nozzle support 19 outside the movable arc electrode 16 so as to surround the movable arc electrode 16. A gas flow path 17 is formed between the movable arc electrode 16 and the insulating nozzle 18. Also,
In the puffer portion 6, a puffer chamber 21 is formed by a puffer cylinder 15 and a puffer piston 20 inserted therein.
The puffer chamber 21 is communicated with the gas flow path 17 through an opening 22 formed in the end surface of the puffer cylinder 15. The puffer piston 20 is supported and fixed to the support member 10 via an insulating member (not shown).

Further, a tubular operation rod 24 having a hollow portion 23 communicating with the tubular movable arc electrode 16 is fixed inside the end portion of the puffer cylinder 15, and the other end of the operation rod 24 is provided with an insulating rod 25. Is connected to an operating device (not shown).
An opening 26 is provided on the side surface of the operating rod 24 on the side of the insulating rod 25.
Is provided, and the hollow portion 23 of the operation rod 24 is communicated with the insulating gas 2 sealed inside the container 1.

In the conventional puffer type gas circuit breaker having the above-mentioned structure, when the operating device (not shown) is driven, the insulating rod 25 and the operating rod 24 move in the opening direction, whereby the movable electrode portion 5 and The puffer cylinder 15 of the puffer section 6 is also driven in the opening direction. As a result, the fixed arc electrode 14 and the movable arc electrode 16 are separated, and an arc 27 is generated between both electrodes. At the same time, the insulating gas compressed in the puffer chamber 21 passes through the opening 22 and the gas flow path 17 and is blown onto the arc 27 from the opening of the tip of the insulating nozzle 18 to extinguish the arc 27. Some of this insulating gas is
The gas flow 28 passes through the hollow portion 23 of the operating rod 24 and is discharged from the opening 26 on the side surface of the operating rod 24 to the outside of the operating rod 24.

Thus, in the conventional puffer type gas circuit breaker,
The gas compressed in the puffer portion 6 is blown to the arc between the electrodes to extinguish the arc, thereby cutting off the current at the current zero point. The gas flow at this time is generated by the pressure difference between the puffer chamber for compressing the gas and the container containing the cutoff portion. Therefore, in order to perform high-speed shutoff and improve the shutoff performance, the gas flow path structure should be improved and the difference between the puffer chamber pressure and the vessel internal pressure should be increased at an early stage to provide a strong It is necessary to obtain sufficient gas blowing power.

Regarding the former improvement of the gas flow path structure, the movable electrode portion 5 and the operating rod 24 for driving the movable electrode portion 5 are made hollow, and the hollow portion
Through 23, a part of the gas blown to the arc generated when the current is cut off is exhausted to improve the gas blowing force.

On the other hand, regarding the latter method, in order to increase the pressure in the puffer chamber early, the operating rod 24 is made of an aluminum alloy, and the weight of the movable part is reduced to increase the gas compression rate in the puffer chamber. Has been devised.

However, the gas exhausted through the hollow portion 23 of the operating rod 24 is not discharged by the arc generated when the current is cut off.
Although heated to 00 to 5000 ° K, the aluminum alloy on the inner surface of the operating rod 24 that comes into contact with this high temperature gas generally has low high temperature strength, and the tensile strength at 200 ° C is reduced to about 1/2 of the room temperature tensile strength. . Therefore, the operating rod 24 under such high temperature
In order to prevent a decrease in the strength of the operating rod, it is necessary to attach a cover made of a material having excellent heat resistance to the inner surface of the operating rod, or to configure a part of the operating rod 24 with a material having high high temperature strength such as steel. There is.

However, if a cover is provided on the inside of the operation rod or the operation rod is made of steel or the like, the weight of the movable part increases, and the gas compression speed in the puffer chamber cannot be increased. It was not possible to achieve the improvement of the blocking performance by shortening the blocking time.

[Object of the Invention] The present invention has been proposed in order to solve the problems of the conventional puffer type gas circuit breaker as described above, and an object thereof is to shorten the blocking time and to greatly improve the blocking performance. It is to provide a puffer type gas circuit breaker that can be operated.

[Summary of the Invention] In the puffer type gas circuit breaker of the present invention, the operating rod is formed in a hollow cylindrical shape, and the central portion of the thick portion of the tubular portion of the operating rod is continuously arranged in the axial direction. It is made of the first fiber-reinforced metal-based composite material that is a composite of fibers and a matrix metal composed of lightweight high-strength metal, and the other part of the operating rod is mixed with non-directionally mixed short fibers and lightweight high-strength. By forming the second fiber-reinforced metal matrix composite material that is composed of a matrix metal composed of metal, the high-temperature strength of the operating rod is enhanced, and the operating rod is lightened to reduce the weight of the movable part. By increasing the pressure in the puffer chamber at the initial stage of the opening operation, the blocking time can be greatly shortened and the blocking performance can be improved.

[Embodiment of the Invention] An embodiment of the present invention will be specifically described below with reference to FIG. The same members as those of the conventional type shown in FIGS. 3 and 4 are designated by the same reference numerals, and the description thereof will be omitted.

* Structure * In the present embodiment, the operating rod 24 has a central portion of the thick portion of the tubular portion, which has an aluminum alloy, which is a lightweight and high-strength metal as a mother phase, and operates an alumina (Al ₂ O ₃ ) continuous fiber. It is formed of the first fiber-reinforced metal matrix composite material 30 arranged in the axial direction of the rod 24 and serving as a reinforcing phase. As this aluminum alloy, A2024 (Cu… 4%, Mg… 1.5%, Mn… 0.5%
Al alloy) is used.

Further, the connecting portion between the movable arc electrode 16 and the insulating rod 25 and the inner and outer surfaces of the central portion of the tubular portion of the operating rod 24 formed of the first fiber-reinforced metal matrix composite material 30,
It is formed of a second fiber-reinforced metal matrix composite material 31 having an aluminum alloy as a matrix phase and non-directionally mixed short fibers as a reinforcing phase. Silicon carbide whiskers (SiC (W)) are used as the short fibers.

The operating rod 24 has alumina arranged therein, and has the same shape as the operating rod 24.
A preformed body of C (W) is preformed, and the molten metal of A2024 is pressure-permeated into the preformed body to be integrally formed.

* Operation * In the puffer type gas circuit breaker of the present embodiment having such a configuration, the central portion of the tubular portion of the operating rod 24 is located at the first position.
The tensile strength and the compressive strength in the axial direction of the operating rod 24 are enhanced by being formed by the fiber-reinforced metal-based composite material 30 of FIG. The shear strength is greatly strengthened by being formed by.

In such a puffer type gas circuit breaker, as in the conventional case, the arc between the electrodes is
However, a part of the insulating gas blown to extinguish the arc 27 becomes a gas flow 28 from the hollow portion 23 of the operating rod 24 through the opening 26 on the side surface to the operating rod 27.
24 Discharged outside. This insulating gas stream 28 is heated by the arc 27 and reaches a high temperature of 4000 to 5000 ° K, but the reinforcing phases of the first and second fiber-reinforced metal matrix composite materials 30 and 31 forming the operating rod 24. Alumina (Al ₂ O ₃ ) that constitutes
Also, since silicon carbide whiskers (SiC (W)) are ceramics and have high strength against high temperature, even if the operating rod 24 comes into contact with the high temperature gas flow at the time of current interruption, the strength is not different from that at room temperature and is strong. Can maintain strength. Therefore, the conventionally used heat-resistant protective cover becomes unnecessary, and it is not necessary to form a part of the operating rod 24 using a heavy material having high high-temperature strength such as steel. The weight of the operating rod 24 and the entire movable part can be reduced, and the opening speed and the gas compression speed in the puffer chamber 21 can be increased.

Next, FIG. 2 shows the time change of the pressure increase in the puffer chamber 21 when the current is cut off. Curve A is the conventional operating rod, and curve B is the puffer chamber 21 with the operating rod of this embodiment.
3 shows the time change of the pressure rise of. That is, as compared with the conventional operating rod, the puffer chamber using the operating rod of this embodiment formed of the fiber-reinforced metal matrix composite material.
The pressure of 21 rises quickly, and the gas blowing force increases early after the opening operation is started. As a result, the breaking performance at the early stage of the opening operation is significantly improved, and high speed breaking is possible.

Further, as shown in the present embodiment, the operating rod is lightened and the opening speed is increased, so that the inter-electrode distance between the fixed electrode portion 4 and the movable electrode portion 5 is increased when the arc is extinguished. Therefore, it is possible to improve the withstand voltage performance against the transient recovery voltage applied between the electrodes after the arc is extinguished, and to improve the breaking performance in the initial stage of the opening operation.

Further, the fiber-reinforced metal matrix composite material forming the operating rod 24 is reinforced with alumina (Al ₂ O ₃ ) and silicon carbide whiskers (SiC (W)) constituting the reinforcing phase to obtain a unit density at room temperature. The tensile strength per hit, so-called specific strength, is about twice that of the metal A2024 that constitutes the matrix phase. Therefore, while maintaining the required strength, the weight of the operating rod 24 formed of the fiber-reinforced metal matrix composite material can be reduced to about 1/2 as compared with the operating rod formed using only A2024. It is possible to further shorten the cutoff time.

In addition, as a result of reducing the weight of the operating rod 24, the weight of the movable part can be reduced, so that the driving force required for the blocking operation can be significantly reduced, and the conventional blocking performance can be maintained while driving. The device can be downsized.

Further, since the reinforcing phase of the fiber-reinforced metal matrix composite material forming the operation rod 24, that is, alumina and silicon carbide whiskers are ceramics, and their hardness is higher than that of metal, the operation formed by the fiber-reinforced metal matrix composite material. The hardness of the rod is significantly higher than that of the operating rod made of aluminum alloy, and the operating rod that slides on the puffer piston 20
The wear resistance of the outer surface of is improved.

* Other Examples * Note that the present invention is not limited to the above-described examples, and as the fiber-reinforced metal matrix composite material forming the operating rod 24, a high strength and light weight such as titanium (Ti) alloy in the matrix phase. The same effect can be obtained when boron (B) fiber, carbon (C) fiber or the like is used as the alloy and the reinforcing phase.

[Effects of the Invention] As described above, according to the present invention, the operating rod is made of the fiber-reinforced metal matrix composite material, and the moving part is made lighter, thereby shortening the interruption time and significantly improving the interruption performance. It is possible to provide a puffer type gas circuit breaker that can be used.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the puffer type gas circuit breaker of the present invention, and FIG. 2 is a diagram showing a time change of the pressure increase of the puffer chamber in the puffer type gas circuit breaker of the present invention and the related art. FIG. 3 is a partially cutaway sectional view of a conventional puffer type gas circuit breaker, and FIG. 4 is a sectional view of a blocking part of a conventional puffer type gas circuit breaker. DESCRIPTION OF SYMBOLS 1 ... Container, 2 ... Insulating gas, 3 ... Cut off part, 4 ... Fixed electrode part, 5 ... Movable electrode part, 6 ... Puffer part, 7 ... Exit part,
8 ... Conductor, 9 ... Insulating spacer, 10 ... Support member, 11 ... Contact, 12 ... Cylindrical insulating member, 13 ... Fixed electrode mounting member, 14
… Fixed arc electrode, 15… Puffer cylinder, 16… Movable arc electrode, 17… Gas flow path, 18… Insulation nozzle, 19… Nozzle support, 20… Puffer piston, 21… Puffer chamber, 22
… Puffer cylinder opening, 23… Operation rod hollow, 24
Operating rod, 25 ... Insulating rod, 26 ... Operating rod opening, 27 ... Arc, 28 ... Gas flow, 30 ... First fiber reinforced metal matrix composite material (Al ₂ O ₃ / A2024), 31 ... Second Fiber reinforced metal matrix composite (SiC (W) / A2024).

Claims (2)

[Claims] 1. A movable electrode portion is provided with a fixed electrode portion and a movable electrode portion which are arranged so as to be able to come into contact with and separate from each other on a common central axis, and a movable puffer cylinder is provided at the tip of an operating rod for driving the movable electrode portion. A puffer piston is provided inside the puffer cylinder, a compression chamber is formed between the movable puffer cylinder and the puffer piston, and the compression chamber is formed against the arc generated when the fixed electrode portion and the movable electrode portion are separated. In a puffer-type gas circuit breaker for extinguishing arc by blowing the arc-extinguishing gas compressed in, the operating rod is formed in a hollow cylindrical shape, and the central portion of the thick portion of the tubular portion of the operating rod is , A first fiber-reinforced metal matrix composite material in which continuous fibers arranged in the axial direction and a matrix metal composed of a lightweight and high-strength metal are composited. A puffer-type gas cutoff characterized in that the portion is formed of a second fiber-reinforced metal matrix composite material in which a short fiber mixed in a non-directional direction and a matrix metal composed of a lightweight high-strength metal are composited. vessel. 2. A lightweight and high-strength metal constituting the fiber-reinforced metal matrix composite material is an aluminum alloy or a titanium alloy, and continuous fibers and short fibers which become a reinforcing phase in combination with the aluminum alloy are alumina,
The puffer type gas circuit breaker according to claim 1, wherein the puffer type gas circuit breaker is a ceramic such as silicon carbide or a fiber material such as boron or carbon.