JPH07176234A - Gas insulating bushing - Google Patents

Abstract

PURPOSE:To obtain a gas insulating bushing which can continue the operation without stopping the current feeding function, and suppresses the scattering of broken pieces when a porcelain tube is broken, so as to prevent the collision of broken pieces against the peripheral equipment. CONSTITUTION:Inside a porcelain tube 1, an insulative partition wall 2 whose lower end is fixed is provided, and the space in the porcelain tube 1 is partitioned to the inner side and the outer side so as to suppress the scattering of broken pieces when the porcelain tube 1 is broken. A protrusion preventive mechanism 14 is installed on the upper end of the insulating partition wall 2 so as to prevent the protrusion of the inner conductor 4 of a bushing when the porcelain tube 1 is broken, and the airtightness of the inner surface of the insulating partition wall 2 is maintained when the porcelain tube 1 is broken. The power feeding function can be thereby maintained. It is preferable that the protrusion preventive mechanism 14 is formed into a ring-shape structure fitting to the groove at the upper side outer periphery of the insulating partition wall 2, and the contact surface between the groove and the ring-shape structure is formed into a tapered surface expanding upward.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention reduces the amount of gas that contributes to the scattering of debris at the time of explosion of a porcelain insulator by partitioning the interior of the porcelain insulator filled with an insulating gas with an insulating partition wall to prevent the scattering of debris. The present invention relates to a gas-insulated bushing that is suppressed.

[0002]

2. Description of the Related Art As shown in FIG. 4, an insulating partition wall 2 having a fixed lower end portion is installed in a porcelain tube 1 filled with an insulating gas, and a space in the porcelain tube 1 is divided into an inner space and an outer space. Has been known for a long time. In this type of gas-insulated bushing, in order to keep the gas pressure in the inner and outer spaces of the insulating partition wall 2 constant, both spaces are connected by a communication passage 3.
However, as shown in FIG. 5, when the porcelain insulator 1 is broken, only the gas in the outer space of the insulating partition wall 2 contributes to the scattering of the fragments, and the gas in the inner space directly contributes to the fragment scattering. do not do. Therefore, the insulating partition wall 2 has an effect of suppressing scattering of fragments and preventing collision of the fragments with peripheral devices.

[0003]

However, the conventional gas-insulated bushing as described above, as shown in FIG.
There is a possibility that the head portion of the porcelain insulator 1 will be blown up at the same time as the destruction of, and at the same time, the inner conductor 4 of the bushing will fly out. Therefore, at the same time as the destruction of the porcelain insulator 1, the energizing function is impaired, and the protruding inner conductor 4 vibrates around the upper fixing point of the aerial lead wire 5 and collides with the peripheral equipment such as the adjacent gas-insulated bushing. May be damaged and the function of one line of substation equipment may be stopped. However, the demand for shortening downtime of substation equipment is expected to become stronger in the future, and technical development for this is an urgent issue.

The present invention solves the above-mentioned conventional problems,
It was made to provide a gas-insulated bushing that suppresses the scattering of debris when a porcelain insulator is broken to prevent the debris from colliding with peripheral equipment and that can continue operation until the equipment is repaired without stopping the energizing function. It is a thing.

[0005]

DISCLOSURE OF THE INVENTION The present invention, which has been made to achieve the above object, defines a space inside a porcelain tube inside and outside by an insulating partition having a fixed lower end, and these spaces are formed by small holes. In a gas-insulated bushing that contacts and suppresses scattering of debris when the porcelain tube is broken, the function to prevent the inner conductor of the bushing from jumping upward when the porcelain tube is broken and to keep the current flowing, and the inner surface of the insulating bulkhead when the porcelain tube is broken A pop-out prevention mechanism having a function of maintaining airtightness is provided at the upper end of the insulating partition. In addition, it is preferable to provide a means for detecting the pressure of both spaces in the porcelain tube divided by the insulating partition. Further, it is preferable that the pop-out prevention mechanism is a ring-shaped structure fitted in a groove on the upper outer periphery of the insulating partition, and the contact surface between this groove and the ring-shaped structure is a tapered surface that widens upward. .

[0006]

In the gas-insulated bushing of the present invention thus constructed, the insulating partition wall divides the inner space of the porcelain tube into the inside and outside to reduce the amount of gas that contributes to the scattering of debris when the porcelain tube is broken. The fact that scattering of fragments can be suppressed is similar to the conventional one. Moreover, since the pop-up prevention mechanism is provided at the upper end of the insulating partition, the internal conductor of the bushing is prevented from popping out upward when the porcelain tube is destroyed, and the internal conductor itself moves to the original position only slightly. Stay Therefore, the protruding internal conductor does not damage the peripheral equipment as in the conventional case. In addition, since the pop-out prevention mechanism maintains the airtightness of the inner surface of the insulating partition even when the porcelain tube is broken, the insulating gas remains filled in the insulating partition and the current can be continued as it is. If the pop-out prevention mechanism is a ring-shaped structure fitted in a groove on the outer periphery of the upper part of the insulating partition wall, and if the contact surface between this groove and the ring-shaped structure is a tapered surface that expands upward, Even when the head chamber of the porcelain insulator collides with the ring-shaped structure of the prevention mechanism, it is possible to prevent the upper end of the insulating partition wall from being destroyed by the impact.

[0007]

The present invention will be described below in more detail with reference to the illustrated embodiments. FIG. 1 is a central longitudinal sectional view of a gas-insulated bushing of an embodiment, 1 is a porcelain tube, and 2 is an insulating partition wall installed therein. An insulating gas such as SF ₆ gas is filled inside the porcelain bushing 1, and an insulating partition wall 2 divides the gas space inside the porcelain bushing 1 into the inside and the outside. Insulating partition 2
It is made of FRP, the lower end of which is fixed to the grounding side metal fitting 6, and the insulating partition wall 2 remains in its original position even when the porcelain insulator 1 is broken.

Reference numeral 7 is a head chamber of the gas insulating bushing, and 8 is a support plate constituting the bottom surface thereof. As shown in the enlarged view of FIG. 2, the upper end portion of the insulating partition wall 2 is supported by the support plate 8 via an O-ring 9 provided on the inner circumference of the support plate 8.
It is slidably supported by. Further, a small hole 10 for communication is provided through the support plate 8, and both spaces inside and outside the insulating partition wall 2 are connected by the small hole 10 to equalize the gas pressure in both spaces.

Reference numeral 4 denotes an internal conductor of the bushing, the upper end of which is fixed to the upper terminal 11 on the upper surface of the head chamber 7 and is connected to the aerial lead wire 5. However, as shown in FIG. 1, the lower end of the inner conductor 4 is connected to the inner conductor 13 of the device via a sliding contact 12. The sliding contact 12 is for absorbing the thermal expansion of the inner conductor 4 due to the heat generation when energized, but there is a margin to keep the contact even if the inner conductor 4 moves a little upward when the porcelain tube is destroyed. I will keep it. The amount is about 10 to 20 mm in this embodiment.

In the present invention, a pop-out prevention mechanism 14 is provided at the upper end of the insulating partition 2. In this embodiment, a stopper 15 is fixed to the insulating partition 2 as the pop-out preventing mechanism 14. A gap of about 10 to 20 mm is provided between the lower surface of the stopper 15 and the upper surface of the support plate 8 described above. Further, on the lower surface of the stopper 15, a flat gasket 16 which serves both as a buffer and as an airtight is provided at a position close to the small hole 10. The pop-out prevention mechanism 14 has both the function of preventing the internal conductor 4 from popping up at the time of crushing the porcelain tube and keeping the current flowing, and the function of keeping the inner surface of the insulating partition 2 airtight.

That is, since the head chamber 7 loses its support when the porcelain insulator 2 is destroyed, the head chamber 7 is lifted upward by the gas pressure acting as shown by the arrow in FIG. However, since the insulating partition wall 2 does not move from a fixed position as described above, and the pop-out prevention mechanism 14 is fixed to the upper end portion thereof, when the head chamber 7 is lifted by about 10 to 20 mm, the support plate for the head chamber 7 is lifted. 8 collides with the pop-out prevention mechanism 14 and prevents the head chamber 7 from moving further upward. Further, since the upper end of the inner conductor 4 is fixed to the head chamber 7, when the inner conductor 4 is similarly lifted by about 10 to 20 mm, it cannot move further upward.
Moreover, since the lower end of the inner conductor 4 does not drop off from the sliding contact 12 by such a movement, even if the porcelain insulator 1 is destroyed, the inner conductor 4 between the inner conductor 13 and the aerial lead wire 5 of the device is still present. It remains connected and is kept energized.

At the same time, as shown in FIG. 3, the flat gasket 16 closes the small holes 10 to prevent the insulating gas in the inner space of the insulating partition 2 from leaking to the outside. Needless to say, the O-ring 9 also helps maintain the airtightness at this time.
Therefore, the surroundings of the inner conductor 4 are still maintained in the original state filled with the insulating gas, and the current-carrying function can be continuously maintained even after the porcelain tube is destroyed.

As described above, the gas-insulated bushing of the present invention maintains the current-carrying function even after the porcelain is broken. As shown in FIG. 1, the porcelain tube is divided by the insulating partition wall 2. A pressure detecting means 17 for the pressures of both spaces in 1;
It is preferable to provide the display means 18 and the transmission means 19. As a result, it was found that the porcelain insulator 1 broke when the pressure in the outer space of the insulating partition wall 2 became atmospheric pressure.
When there is a difference in pressure between the two spaces, it can be seen that the local portion of the porcelain insulator 1 is damaged. In this way pressure detection means
The numeral 17 can be used for monitoring the porcelain bushing 1, and if the pressure value is transmitted to the monitoring device by the transmitting means 19, it can be monitored from a remote location.

In the embodiment described above, the stopper 15 of the pop-out prevention mechanism 14 is fitted in the shallow groove on the upper outer periphery of the insulating partition 2. However, in such a structure, when the support plate 8 of the head chamber 7 collides with the stopper 15 during the explosion of the porcelain insulator, the impact energy thereof may cause cracks at the upper end of the insulating partition wall 2 to cause destruction. There is. This is an insulating partition 2 with a stopper 15.
The upper end of the groove is pushed up to generate a tensile stress in the radial direction at the bottom of the groove, because the FRP of the laminated structure forming the insulating partition 2 is weak against the tensile stress in this direction.

Therefore, in the second embodiment, as shown in FIGS. 7 and 8, the pop-out prevention mechanism 14 is a ring-shaped structure fitted in a groove 20 on the outer periphery of the upper part of the insulating partition 2, and the groove 20 and The contact surface with the ring-shaped structure is a tapered surface that widens upward. If such a structure is adopted, as shown in FIG. 9, the stopper 15 is provided in the head chamber 7 when the porcelain insulator explodes.
Even when it collides with the support plate 8 of 1, the cracks are less likely to occur. The first reason is that a part of the pushing-up force by the stopper 15 acts as a compressive force in the inner diameter direction toward the bottom of the groove 20 to prevent the tensile stress from being generated. The FRP having a laminated structure that constitutes the insulating partition wall 2 has a strong property against compressive stress and is unlikely to crack. The second use is that friction is generated at the tapered contact surface between the groove 20 and the ring-shaped structure, which consumes part of the kinetic energy acting on the stopper 15. In addition, with such a structure, even if a crack is generated at the bottom of the groove 20, the stopper 15 has a tapered fitting structure that widens upward, so that the stopper 15 may not come out of the groove 20 of the insulating partition 2. Absent.

Further, by interposing the rubber-like cushioning material 21 as shown in the drawing on this contact surface, a more excellent destruction preventing effect can be obtained. This rubber-like buffer 21 moves so as to flow in a liquid state when pushed, and transmits the collision energy to the groove 20 as a uniform pressure. Therefore, it is possible to prevent the occurrence of local stress that causes cracking or peeling of the FRP. Further, since the impact energy is further consumed in the process of the deformation of the rubber-like buffer material 21 in this way, the axial force finally transmitted to the insulating partition wall 2 is reduced and it becomes difficult to break.

[0017]

As described above, the gas-insulated bushing of the present invention can suppress the scattering of debris at the time of breaking the porcelain tube and prevent the collision of the debris with the peripheral equipment, and the internal part at the time of breaking the porcelain tube. By preventing the conductor from jumping out and maintaining the airtightness of the inner surface of the insulating partition, there is an advantage that the operation can be continued until the equipment is repaired without stopping the energizing function. Therefore, the present invention makes a great contribution to the industry as a highly reliable gas-insulated bushing.

[Brief description of drawings]

FIG. 1 is a central longitudinal sectional view showing an embodiment of the present invention.

FIG. 2 is a central longitudinal sectional view showing a main part of the embodiment.

FIG. 3 is a central longitudinal cross-sectional view showing a situation when a porcelain tube is destroyed in a main part of the embodiment.

FIG. 4 is a central longitudinal sectional view showing a conventional gas-insulated bushing.

FIG. 5 is a cross-sectional view showing a state of a conventional gas-insulated bushing when a porcelain insulator is broken.

FIG. 6 is a cross-sectional view showing a situation in which a crack is formed at the upper end of the insulating partition.

FIG. 7 is a central vertical cross-sectional view showing the main parts of the second embodiment of the present invention.

FIG. 8 is a plan view showing a stopper according to a second embodiment.

FIG. 9 is a central longitudinal cross-sectional view showing a situation when the porcelain insulator of the second embodiment is broken.

[Explanation of symbols]

1 porcelain tube, 2 insulating partition, 4 inner conductor, 14 popping out prevention mechanism, 17 pressure detection means, 10 small holes, 20 grooves,
21 rubbery cushion

Claims (3)

[Claims] 1. A gas-insulated bushing in which a space inside a porcelain tube is divided into an inner space and an outer space by an insulating partition having a fixed lower end, and these spaces are connected by a small hole to suppress scattering of fragments when the porcelain pipe is broken. A pop-out prevention mechanism equipped with a function to prevent the inner conductor of the bushing from jumping up when the porcelain tube is broken and to keep the current flowing and a function to keep the inner surface of the insulating partition wall airtight when the porcelain tube is broken is provided. A gas-insulated bushing that is provided at the upper end. 2. The gas-insulated bushing according to claim 1, further comprising means for detecting the pressure in both spaces in the porcelain tube divided by the insulating partition wall. 3. The pop-out prevention mechanism is a ring-shaped structure fitted in a groove on the upper outer periphery of the insulating partition, and the contact surface between the groove and the ring-shaped structure is a tapered surface that widens upward. The gas insulating bushing according to claim 1.