JPH0568811B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a puffer-type gas cylinder and disconnector with an improved arc extinguishing chamber shape, and in particular to a gas flow for efficiently removing high-temperature gas remaining after arc extinguishing. This paper relates to a gas shield and disconnector with an improved path.

[Technical Background of the Invention] In recent years, as the short-circuit capacity has increased due to an increase in power transmission capacity, the short-circuit capacity of a gap switch has also been increasing. On the other hand, in order to downsize equipment, efforts are being made to increase the shear breaking capacity per point and reduce the number of shear breaks connected in series. For this reason, it is required to optimize the gas blowing equipment as well as the design of the electric field between the poles of the cutter and cutter to improve the cutoff performance of the cutter.

This point will be explained regarding the conventional puffer type gas shield and disconnector shown in FIG. The figure shows the state in the middle of opening.

A cylindrical fixed electrode 1 and an annularly arranged movable electrode 2 are connected to an operating mechanism (not shown) on the right side of FIG. 4 by a hollow operating rod 3 having an opening 3. A movable puffer cylinder 4 is fixedly attached to the operating rod 3, and a compression chamber 6 is formed between the movable puffer cylinder 4 and a fixed puffer piston 5 having an opening 5a. Further, the puffer cylinder 4 is provided with an opening 4a, and the puffer cylinder 4 is provided with an opening 4a.
Insulating nozzle 7a and insulating cover 7b fixed to
The gas in the compression chamber 6 can flow in and out through the cylindrical gas passage 8 formed by the compression chamber 6 . These parts are housed in an insulating container 9, and an internal space 10 of the insulating container 9 is filled with arc-extinguishing gas.

In this embodiment, the container is made of an insulating material, but puffer type gas cylinders and disconnectors are also known in which the above-mentioned arc extinguishing chamber member is supported inside a metal tank by an insulating material.

A shear breaker command is given to the shear breaker, and an operation mechanism (not shown) operates to close the operation rod 3.
When the movable electrode 2 connected to the operating rod 3 is separated from the fixed electrode 1 as shown in the figure, an arc 11 is generated between the electrodes 1 and 2.
On the other hand, as a result of the movement of the operating rod 3, the movable puffer cylinder 4 attached to the operating rod 3 also moves to the right, compressing the arc-extinguishing gas in the compression chamber 6. This gas flows through the opening 4 of the puffer cylinder 4.
a, the gas is blown onto the arc 11 through the gas flow path 8 and the gas jet port 8a, and extinguishes the arc 11. This gas flow is split into two flows 12a and 12b, and the gas flow 12a split to the left in FIG.
The surrounding space 10 passes through the opening 7c of the insulating nozzle 7a.
leaks to. On the other hand, the gas flow 12b split to the right.
are the opening 7d of the insulating cover 7b and the opening 1 after the fixed electrode 1 is separated from the movable electrode 2.
3. It flows out into the surrounding space 10 through the opening 3a of the operating rod 3 and the opening 5a of the fixed puffer piston 5.

[Problems with the Background Art] In such a non-operational or disconnection operation, after the arc is extinguished by the above-described mechanism, positively and negatively ionized plasma and gas heated to a high temperature by the arc remain. Since these plasma gases and high-temperature gases have high electrical conductivity and low electrical dielectric strength, a current may flow between the electrodes 1 and 2 due to the re-electromotive voltage applied between the electrodes 1 and 2 after the arc is extinguished. Due to reasons such as electrical breakdown occurring between the two, it is easy to cause failure of the sheathing. The puffer-type gas cylinder disconnector is designed so that residual plasma and high-temperature gas, which tend to cause failure of the cylinder, are also removed from between the electrodes 1 and 2 by the aforementioned gas flow. Therefore, the breaker performance of a puffer-type gas breaker is determined by how efficiently the arc-extinguishing gas is blown between the electrodes.

For example, in the blowing mechanism of a conventional gas shield and disconnector as shown in FIG. 4, the gas flow 12b is blown onto the arc even before the fixed electrode 1 comes out of the throat portion 7a-1 of the insulated nozzle 7a. In addition to being able to extinguish the arc over a wide arc time range, the electrode metal melted and vaporized by the heat of the arc flows into gas flows 12a and 12b from between the electrodes 1 and 2.
This has the advantage that the gas between the electrodes 1 and 2 is not affected by adverse effects such as an increase in the conductivity of the gas or a decrease in the electrical dielectric strength.

However, on the other hand, a stagnation region occurs at the split point of the gas flows 12a and 12b, where the gas flow velocity is significantly reduced. Since the gas blowing efficiency is significantly reduced in the vicinity of this stagnant region, the plasma gas and high temperature gas 14 remaining in this region are not removed and remain in this region, as shown in FIG. As a result, the electrical breakdown strength near the stagnant region is lower than that of the gas in other regions.
For this reason, especially during BTF shatter, where dielectric breakdown due to re-electromotive voltage applied between the electrodes after arc extinguishing is a problem, dielectric breakdown near the stagnation region causes re-ignition between the electrodes, and the shatter occurs. There was a risk of failure.

[Object of the invention] The present invention was made in view of the above problems, and
The object of the present invention is to provide a puffer-type gas shield and disconnector that can quickly remove plasma gas and high-temperature gas remaining in the vicinity of the stagnation region after erasing from between the electrodes and improve insulation recovery characteristics.

[Summary of the Invention] The gas shield disconnector of the present invention has a second fixed piston disposed inside a hollow operating rod, and the inside of the operating rod is surrounded by the second fixed piston during the first half of the opening operation. A gas flow path toward the rear side of the second fixed piston is formed to form a cylinder into which the second fixed piston is inserted in the latter half of the opening operation.

With this configuration, in the first half of the opening operation, it operates in the same way as a conventional puffer-type gas insulator or disconnector, taking advantage of its advantages, while in the second half of the opening operation, a second valve is installed inside the operating rod. A gas compression/blowing mechanism is formed to make the gas flow unidirectional, eliminate the stagnation area, quickly remove plasma gas and high temperature gas from between the electrodes, and enable prompt insulation recovery after arc extinguishment. It is.

[Embodiment of the Invention] An embodiment of the present invention will be described in detail based on FIGS. 1 to 3. Components that are the same as those of the conventional puffer-type gas shield and disconnector shown in FIGS. 4 and 5 are designated by the same reference numerals and their explanations will be omitted.

FIG. 1 shows the state in the first half of the opening operation of the puffer type gas shield breaker according to the present invention. In the figure, a second fixed piston 22 is disposed inside a hollow operating rod 21. As shown in FIG. An enlarged view of the operating rod 21 and the second fixed piston 22 is shown in FIG. In the figure, the outer diameter of the second fixed piston 22 is designated as A. The inside of the operating rod 21 is a space 23 in which the second fixed piston 22 slides during the first half of the cutting operation.
Let B be the inner diameter of the second fixed piston 2, so that the relationship B>A is satisfied.
A gas flow path 24 is configured around 2. Furthermore, if the inner diameter of the portion 25 on which the second fixed piston 22 slides in the second half of the shearing operation is A', the second cylinder is formed so as to satisfy the relationship A'=A. Furthermore, the movable electrode 2 of the operating rod 21
The side end portion 26 is provided with an opening 27 having a diameter of C.

When a shearing command is given to the puffer-type gas shear breaker of this embodiment having such a configuration, the pressure is increased in the compression chamber 6 during the first half of the shearing operation, as shown in FIG. The arc-extinguishing gas is supplied to the opening 4a of the movable puffer cylinder 4, the gas passage 8, and the gas outlet 8.
It separates into two streams 28a and 28b via a. A part of the gas flow 28a flows out into the space on the left side in the figure through the opening 7c of the insulating nozzle 7a, and another part 28b of the gas flow flows through the opening 7d of the insulating cover 7b.
The gas flows to the right in the figure through the opening 27 of the operating rod 21 and the gas passage 27 around the second fixed piston 22, and flows out through the opening 5a of the puffer piston 5 into the surrounding space.

At this stage, the gas shutoff switch of this example is as follows:
It functions in the same way as the conventional puffer-type gas shield and disconnector shown in Figure 1, with the fixed electrode 1 connected to the insulated nozzle
Since a part of the gas flow 28b is blown onto the arc 11 even before it escapes from the throat portion 7a-1 of the arc 11, efficient arc extinguishment is possible even in a region where the arc time is short.

When the shearing operation further progresses and reaches the latter half, the second fixed piston 22 is inserted into the portion 25 of the operating rod 21 whose inner diameter is A', as shown in FIG. It consists of This second
The arc-extinguishing gas whose pressure has been increased in the compression chamber 29 is
A gas flow 28c is formed which flows out to the left in the figure through the opening 27 of the operating rod 21 and flows through the opening 7d of the insulating cover 7b and the opening 7c of the insulating nozzle 7a. At this stage, since the stagnation region disappears, residual plasma gas and high-temperature gas are quickly removed, and rapid insulation recovery characteristics can be realized.

In order for the gas flow 28b shown in FIG. 3 to flow efficiently during the first half of the shearing operation, the effective cross-sectional area of the opening 27 at the end of the operating rod 21 must be larger than that of the opening of the movable electrode 2 (as shown in FIG. 3). It must be at least 10% of the effective cross-sectional area shown in 2a). In addition, in order to efficiently compress the gas in the second compression chamber 29 in the latter half of the cutting operation, the effective cross-sectional area of the opening 27 of the operating rod must be larger than the effective cross-sectional area inside the second compression chamber 29. It is desirable that it be 40% or less. Furthermore, the transition from the state shown in FIG. 1 to the state shown in FIG. Good arc extinction can be achieved.

[Effects of the Invention] As described above, according to the present invention, a gas flow is generated by forming a second gas pressure chamber inside the operating rod in the latter half of the shearing operation, and after the arc is extinguished. This allows the gas flow to flow out in the direction of the opening of the insulating nozzle, so the gas flow is directed in the same direction, and the plasma gas and high temperature gas remaining near the stagnation area can be quickly removed from between the electrodes. Therefore, it is possible to provide a puffer-type gas insulator and disconnector that can improve insulation recovery characteristics.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing the first half of the shielding operation of a puffer-type gas shield and disconnector according to an embodiment of the present invention, and Figure 2 is a section showing the structure of the operating rod and fixed piston in Figure 1. An enlarged sectional view, FIG. 3 is a cross-sectional view showing the latter half of the sheathing operation of the puffer-type gas shield and disconnector of the present invention, and FIG. 4 shows the shielding operation of the conventional puffer-type gas shield and disconnector. FIG. 5 is a partially enlarged sectional view showing the gas flow of the insulating nozzle and movable electrode of FIG. 4. 1...Fixed electrode, 2...Movable electrode, 4...Puff cylinder, 5...Puff piston, 6...
Compression chamber, 7a... Insulating nozzle, 7a-1... Throat portion of insulating nozzle, 7b... Insulating cover, 7c
...Insulating nozzle opening, 8...Gas flow path, 8a
...Gas outlet, 11...Arc, 12a, 12
b... Gas flow, 21... Operating rod, 22... Second fixed piston, 23, 25... Space portion, 24
...Gas flow path, 26...Operation rod end, 27...
...openings, 28a, 28b, 28c...gas flow,
29...Second compression chamber.

Claims (1)

[Scope of Claims] 1 Fixed electrodes that are arranged with a common central axis and can be moved toward and away from each other; and fixed electrodes that are arranged opposite to this fixed electrode and are in contact with each other so as to surround this fixed electrode in an open state. an electrode pair consisting of movable electrodes arranged in an annular manner; an insulated nozzle forming a cylindrical gas flow path located around the movable electrode and a gas jet port located around the central axis; a movable puffer cylinder that is fixed and has an opening that allows gas to flow in and out of the gas passage; and a fixed puffer piston that is inserted into the puffer cylinder and arranged to define a compression chamber between the puffer cylinder and the puffer cylinder. It has a hollow operating rod that connects the movable electrode and the movable puffer cylinder to the operating mechanism, and compresses the compressor in the compression chamber against the arc generated between the fixed electrode and the movable electrode when the electrodes are opened. The arc-extinguishing gas is blown through the movable puffer cylinder opening, the gas flow path, and the jet port, and a second fixed piston is disposed inside the operating rod, and the hollow operating rod is The interior forms a gas flow path around the fixed piston toward the rear side of the second fixed piston in the first half of the opening operation, and forms a cylinder into which the fixed piston is inserted in the second half of the opening operation. A patchwork type gas disconnector characterized by having a shape that makes it appear as if it were to be used. 2. The puffer type gas cylinder disconnector according to claim 1, wherein the opening diameter of the movable electrode side end of the operating rod is smaller than the inner diameter of the cylinder portion inside the operating rod. 3. The effective cross-sectional area of the opening at the movable electrode side end of the operating rod is 40% or less of the effective cross-sectional area of the internal cylinder portion, and is 10% or more of the effective cross-sectional area of the internal opening of the annular movable electrode. A puffer type gas shield disconnector according to claim 1. 4. The puffer according to claim 1, wherein the second fixed piston is inserted into a cylinder portion inside the operating rod in synchronization with the exit of the fixed electrode from the throat portion of the insulating nozzle. Shaped gas cutter.