KR20160003826U - Fixed Structre of High Speed Earthing Switch - Google Patents

Fixed Structre of High Speed Earthing Switch Download PDF

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Publication number
KR20160003826U
KR20160003826U KR2020150002725U KR20150002725U KR20160003826U KR 20160003826 U KR20160003826 U KR 20160003826U KR 2020150002725 U KR2020150002725 U KR 2020150002725U KR 20150002725 U KR20150002725 U KR 20150002725U KR 20160003826 U KR20160003826 U KR 20160003826U
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KR
South Korea
Prior art keywords
shield
contact
discharge hole
divided
earthing switch
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Application number
KR2020150002725U
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Korean (ko)
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KR200489975Y1 (en
Inventor
한재원
Original Assignee
엘에스산전 주식회사
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Priority to KR2020150002725U priority Critical patent/KR200489975Y1/en
Publication of KR20160003826U publication Critical patent/KR20160003826U/en
Application granted granted Critical
Publication of KR200489975Y1 publication Critical patent/KR200489975Y1/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/02—Details
    • H01H33/04—Means for extinguishing or preventing arc between current-carrying parts
    • H01H33/08—Stationary parts for restricting or subdividing the arc, e.g. barrier plate
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/02—Details
    • H01H33/04—Means for extinguishing or preventing arc between current-carrying parts
    • H01H33/20—Means for extinguishing or preventing arc between current-carrying parts using arcing horns
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/02—Details
    • H01H33/53—Cases; Reservoirs, tanks, piping or valves, for arc-extinguishing fluid; Accessories therefor, e.g. safety arrangements, pressure relief devices

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  • Circuit Breakers (AREA)

Abstract

The present invention relates to a fixed side structure of a high-speed earthing switch capable of easily discharging a high-temperature insulating gas generated by an arc when a shield is changed by changing a shape of a shield.
In order to achieve the above object, the present invention is directed to a hollow-type split contact which is brought into contact with a movable contact provided on a movable side, a shield which surrounds the split contact and has a first discharge hole formed at an upper portion thereof, And a second exhaust hole communicating with the inside of the divided contact at a position corresponding to a lower end of the hollow portion of the divided contact, wherein the shield is formed on the side wall And further includes a plurality of third discharge holes.

Description

[0001] The present invention relates to a high-speed earthing switch,

The present invention relates to a high-speed earthing switch, more particularly, to a high-speed earthing switch that changes a shield located at a fixed side of a high-speed earthing switch and a peripheral structure thereof so as to easily discharge a high- And a fixed side structure of the switch.

The gas insulated switchgear is installed on the power line for the power station or substation and not only artificially opens and closes the load current in normal use condition but also safely cuts off the abnormal current in case of occurrence of abnormal current such as accident or short circuit, It is an opening / closing device of super high voltage power system that protects electric power equipment.

As is well known, the gas insulated switchgear is composed of a plurality of electric power devices such as a circuit breaker, an isolator, and a high-speed earthing switch, which are high-level objects, as an electric line opening and closing device.

The high-speed earthing switch is roughly divided into a movable side and a fixed side, and the movable side and the fixed side are provided inside the tank.

Here, the fixed side is insulated from the tank by a known spacer, and the movable side is configured to be movable to contact or separate from the fixed side by a known driving device (not shown) Respectively.

Further, the tank inside the movable side is in contact with the fixed side insulation gas, for example for extinguishing an arc generated when separated from the fixed side, sulfur hexafluoride gas (SF 6 ).

The fixed side of the high-speed earthing switch receives a current from the disconnector, and when the abnormal current is generated, the movable side contacts the fixed side to apply an abnormal current from the disconnector in the order of the fixed side, the movable side and the tank, .

FIG. 1A is a cross-sectional view showing a structure of a fixed side of a high-speed earthing switch according to the prior art, and FIG. 1B is a perspective view of FIG. 1A.

1A and 1B, a fixed side structure of a high-speed earthing switch according to the related art includes a hollow divided contact 20 which is in contact with a movable contact 10 provided on a movable side, A shield 30 having a first discharge hole 31 formed in the center of its upper portion and a recess 42 in which the divided contact 20 and the shield 30 are fixed, And a second discharge hole 41 communicating with the inside of the divided contact 20 at a position corresponding to the hollow bottom end 21.

Hereinafter, each component of the high-speed earthing switch fixed side structure will be described in more detail.

The slit 23 is formed in the cylindrical wall 22 of the divided contact 20 so that the movable contact 10 provided on the movable side when the abnormal current flows causes the split contact The contact portion 24 of the split contact 20 is extended in the radial direction and elastically contacted to the movable contact 10 so that the gap between the split contact 20 and the movable contact 10 Thereby ensuring good electrical contact.

The slit 23 is also connected to the slit 23 through the slit 23 even when the contact portion 24 of the split contact 20 is clogged by the movable contact 10 when the movable contact 10 is inserted into the split contact 20 So that the insulating gas can communicate with the inside and outside of the divided contact 20.

Meanwhile, the shield 30 protects the divided contact 20 during assembling or repairing work, as well as shields the influence of the electric field caused by the high voltage application of the divided contact 20 and the movable contact 10, The first discharge hole 31 of the shield 30 allows the movable contact 10 to enter and exit, and allows the high-temperature insulating gas generated by the arc to be discharged to the upper portion of the fixed side of the high-speed earthing switch.

The conductive container 40 to which the split contact 20 and the shield 30 are fixed is disposed at a position corresponding to the lower hollow portion 21 of the divided contact 20 in the interior of the divided contact 20, And a second discharge hole 41 communicating with the high-voltage earthing switch so that the high-temperature insulating gas is discharged to the lower side of the fixed side of the high-speed earthing switch.

When the abnormal current signal is applied to the conductor container 40 to which the load current has been applied through the disconnecting device 50 to be grounded in the fixed side structure of the conventional high speed earthing switch, Is inserted into the contact portion 24 of the divided contact 20 by a driving device (not shown) so that an abnormal current from the disconnecting device 50 is supplied to the conductive container 40, the fixed contact 20, (10), and a tank (not shown).

 However, when the movable contact 10 is inserted into the contact portion 24 of the divided contact 20 in the fixed side structure of the high-speed earthing switch constructed as described above, the contact portion 24 and the movable contact 10 An arc is generated.

This arc is a gas hexafluoride gas (SF 6 < RTI ID = 0.0 > ), But the insulating gas produced by the arc is momentarily heated to a high temperature.

The high-temperature insulating gas generated by the arc causes deformation and destruction of the contact portion 24 and the shield 30 of the movable contact 10, the divided contact 20 and the contact portion 24 of the divided contact 20, And the movable contact 10, and weakening the electric field shielding function of the shield 30. Therefore, it is necessary to quickly discharge the high-speed earthing switch.

In the fixed side structure of the conventional high-speed earthing switch, as described above, the first and second discharge holes 31 and 41 are provided as the passages for quickly discharging the insulating gas at a high temperature. The movable contact 10 is connected to the divided contacts The insulating gas generated by the arc due to the volume change inside the divided contact 20 flows into the fixed contact 20 through the slit 23 and the first discharge hole 31 And then discharged to the lower portion of the conductive container 40 through the second discharge hole 41. [

However, since the first and second discharge holes 31 and 41 do not serve as a sufficient passage for discharging the insulating gas at a high temperature, the insulating gas of high temperature may be shielded by the shield 30 and the conductive container (Hereinafter, referred to as a shield internal space 32) defined by the contact portions 24 and 40 of the divided contact 20 to cause an abrupt pressure rise in the internal space 32 of the shield, Deforming and burning of the movable contact 10 as well as deformation of the shield 30 are caused, which adversely affects the performance of the high-speed earthing switch.

As shown in FIG. 1, the shield 30 of the conventional high-speed earthing switch includes a hemispherical dome portion 33 and a support ring 34 for supporting the dome portion 33 , The following operation is required for the completion of the shield 30 according to the related art.

First, the dome portion 33 should be formed into a dome shape by cutting the thin plate material after cutting the thin plate material. The support ring 34 is formed by machining the raw material into a ring shape .

A screw hole is formed in the outer circumferential surface of the support ring 34 to engage the dome portion 33 and the support ring 34 and a screw hole is formed in the outer circumferential surface of the dome portion 33 at the corresponding position .

After the machining operation of the dome portion 33 and the support ring 34 is completed, the support ring 34 is inserted into the dome portion 33 so that the screw holes of the dome portion 33 and the support ring 34 are aligned with each other And the dome portion 33 and the support ring 34 were to be joined by fastening a coupling member such as a plate bolt 35 to these screw holes.

As a result, in order to complete the shield 30 of the high-speed earthing switch according to the prior art, there has been a problem that the machining operation such as cutting operation, forming operation, machining operation, assembling operation, and the like is troublesome and requires a long time.

In addition, since the shield 30 of the high-speed earthing switch according to the prior art is made of a thin copper material, it is difficult to handle the shield 30 and its durability is weak, and the shield 30 is vulnerable to thermal stress due to high- There was a problem.

In addition to this, the shield 30 can be easily damaged by the operator during assembly work or repair work of the high-speed earthing switch, which may weaken the electric field shielding function of the shield.

The object of the present invention is to provide a high-speed earthing switch capable of smoothly discharging a high-temperature insulating gas generated by an arc at the time of grounding.

The present invention has another purpose to provide a shield having thermal stress and durability against external impact to a high-speed folding switch of a gas insulated switchgear.

The present invention has another object to provide a shield capable of reducing machining and assembling time to a high-speed folding switch of a gas insulated switchgear.

In order to achieve the above object, there is provided a shielding device comprising: a hollow divided contact contacted by a movable contact provided on a movable side; a shield formed to surround the divided contact and having a first discharge hole formed on the upper side; And a shielding container having a recess to which the shield is fixed and a second exhaust hole communicating with the interior of the split contact at a position corresponding to a lower end of the hollow portion of the split contact, And further includes a plurality of third discharge holes formed in the side wall.

Here, the third discharge hole may be an elongated hole whose longitudinal axis is formed in a circumferential direction, and the third discharge hole may be two to four.

In addition, a gap may be formed between the outer circumferential surface of the shield and the inner circumferential surface of the conductor container so that the insulated gas discharged from the third discharge hole may be discharged. At this time, a round portion is formed in the outer edge of the third discharge hole It is possible.

Further, a cut portion is formed in both side walls perpendicular to the axial direction of the conductor container in a wall surface constituting the inner circumferential surface of the concave portion, and the third discharge hole of the shield is arranged to face the cut portion, So that the high-temperature insulating gas can be smoothly discharged to both sides of the conductor container.

The inner diameter of the second discharge hole may be the same as the inner diameter of the divided contact.

An angle formed by a straight line contacting the outermost portion of the contact portion of the split contact parallel to the axis of the shield and the tangent line of the first discharge hole may be 45 degrees at the maximum.

In addition, the shield may be an integral type shield formed by processing one raw material.

The fixed side structure of the high-speed earthing switch according to the present invention forms the third discharge hole in the side wall of the shield, so that the high-temperature insulating gas generated by the arc can be smoothly discharged through the third discharge hole.

In particular, the present invention can arrange such that the third discharge hole of the shield faces the cut portion formed on both sides of the conductor container, and the high-temperature insulating gas can be smoothly discharged to both sides of the conductor container through the third discharge hole without clogging.

The present invention also analyzes the decrease in the electric field shielding ratio of the shield according to the size change of the first discharge hole formed in the shield, so that the size of the first discharge hole can be enlarged compared with the prior art without reducing the shielding ability of the shield. It can be discharged more smoothly.

The fixed side structure of the high-speed earthing switch according to the present invention is improved in the insulating gas discharging ability at a high temperature as compared with the conventional case, so that the pressure and the thermal stress in the shield internal space due to the high temperature insulating gas are lowered, It is possible to prevent damage to the liver.

The present invention also improves the thermal stress and durability against external impact by machining raw material of one copper material and providing a sufficient thickness, instead of fabricating a shield from a copper plate of a thin plate as in the prior art.

In the present invention, if the shielding is manufactured by machining raw materials of one copper material, it is possible to omit the process for assembling the shield as well as to simplify the manufacturing process, thereby improving the overall productivity for shielding .

1A is a cross-sectional front view of a fixed side structure of a high-speed earthing switch according to the prior art.
1B is a perspective view of FIG. 1A.
2A is a three-dimensional cross-sectional view of a fixed side structure of a high-speed earthing switch according to the present invention.
2B is a perspective view of the fixed side structure of the high-speed earthing switch according to the present invention
Fig. 3 is a perspective view of the shield applied to Fig. 2b.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings, which are intended to illustrate the present invention in such a manner that a person skilled in the art can easily carry out the present invention. And does not imply that the technical idea and scope of the design is limited.

Although the fixed side structure of the high-speed earthing switch according to the present invention has the same divided contact as the conventional one, there is a difference in the shape, number, size, and peripheral configuration of the shielding process, , Which will be described in more detail below.

As shown in FIGS. 2A and 2B, the fixed side structure of the high-speed earthing switch according to the present invention according to the present invention includes a hollow divided contact 200 which is contacted by the movable contact 100 provided on the movable side, A shield 300 having a first discharge hole 310 formed in the center of the upper portion and a concave portion 420 to which the divided contact 200 and the shield 300 are fixed, In addition to the conductive container 400 having the second discharge hole 410 communicating with the interior of the divided contact 200 at a position corresponding to the hollow bottom 210 of the housing 200, And a plurality of third discharge holes 350 formed radially in the discharge port 340.

The third discharge hole 350 is formed in the upper part of the shield 300, that is, in the dome part 330, but in the shield 300, in order to minimize the influence of the electric field generated in the divided contact 200 and the contact part 240. [ The sidewall 340 may be formed of a metal.

As shown in FIG. 2A and FIG. 3, the third discharge hole 350 may be formed in various shapes. However, the area of the third discharge hole 350 may be enlarged to smoothly discharge the insulating gas at a high temperature, It is preferable that the long axis is an elongated hole formed in the circumferential direction of the side wall 340 of the shield 300 so as to minimize the influence of the electric field due to the formation of the shield 300.

The present invention is not limited to the number of the third discharge holes 350. However, if the third discharge hole 350 is formed too much, it takes much time to process the discharge hole 350, As the resistance increases, it is preferable that the number of the third discharge holes 350 is two to four.

When the gap 440 is provided between the outer circumferential surface of the shield 300 and the inner circumferential surface of the concave portion 420 of the conductive container 400 in addition to the above configuration, Is discharged to the upper portion of the fixed side structure of the high-speed earthing switch through the gap 440, so that the high-temperature insulating gas can be smoothly discharged.

On the other hand, if the rounded portion R is formed at the outer edge of the third discharge hole 350, the discharge of the insulating gas at a high temperature is smooth because the rounded portion R separates the insulating gas from the gap 440, Because it induces the direction to move along the side wall 340 of the shield 300 and the wall surface 450 of the concave portion 402 forming the side wall 340 of the shield 300.

Hereinafter, the arrangement of the third discharge hole 350 will be described.

The conventional conductor container 400 is formed with a divided contact 200 and a recess 420 on which the shield 300 is mounted. For convenience of repairing, cutouts 430 are formed on both side walls orthogonal to the axial direction of the conductor container 400 as shown in FIG. 1B.

The present invention is characterized in that when the third discharge hole 350 is disposed toward the cut-out portion 430 in the arrangement of the third discharge hole 350, the insulating gas remaining in the shield internal space 320 can be easily The third discharge hole 350 of the shield 300 is disposed in the direction of the cutout 430. [

If the third discharge hole 350 is disposed in the direction of the cutout 430 as described above, it is possible to prevent the flow of the high-temperature insulating gas discharged through the third discharge hole 350 to the outside of the third discharge hole 350 Since there is no element at all, the discharge of the insulated gas can be smooth.

The inner diameter of the second discharge hole 410 may be formed to be equal to the inner diameter of the divided contact 200 for smooth discharging of the insulating gas at a high temperature.

In the fixed-side structure of the high-speed earthing switch according to the prior art, the inner diameter of the second discharge hole 41 is made small so that the high-temperature insulating gas generated by the arc is transferred to the inner space 32 of the shield 30, There is a problem in that it can not be smoothly discharged to the lower portion of the conductive container 40 when passing through the second discharge hole 41 from the second discharge hole 41.

However, since the second discharge hole 410 according to the present invention has the inner diameter equal to the inner diameter of the divided contact 200 as compared with the prior art, a high-temperature insulating gas flows down the second discharge hole 410 It may be discharged smoothly.

In setting the size of the first discharge hole 31, the size of the first discharge hole 31 may be set to a small value such that the movable contact 10 does not interfere with the shielding of the divided contact 20, There was not enough consideration for the discharge of high-temperature insulating gas.

However, in this embodiment, the straight line C 'contacting the outermost portion of the contact portion 240 of the divided contact 200 parallel to the axis C of the shield 300 and the tangent line C' 'of the first discharge hole 310, The shielding ability of the shield 300 is reduced when the size of the first discharge hole 310 defined by the angle (a) is increased. However, in view of the fact that the discharge amount of the insulating gas at a high temperature increases, The size of the first discharge hole 310 can be maximized up to 45 degrees within a range that does not affect the electric field shielding ability of the first discharge hole 300.

The shield 300 according to the present invention, unlike the prior art, is not a method of cutting a thin copper material plate and joining it with a separately formed support ring, but integrating one raw material.

Therefore, it is unthinkable that the shield 30 according to the related art is structurally weakened when the discharge hole, particularly the third discharge hole 35, is formed on the side surface thereof to form the third discharge hole 35 The shield 300 according to the present invention is capable of forming a third discharge hole 350 on the side surface of the shield 300 by applying a single raw material to a sufficient size or thickness to process the raw material, It is possible to provide durability against impact.

When the shield 300 is manufactured by machining the raw material of one copper material as described above, not only the manufacturing process is simple but also the process for assembling the shield 300 can be omitted, Productivity can be improved.

Although the present invention has been described in connection with the above-mentioned preferred embodiments, those skilled in the art will readily appreciate that various modifications and changes may be made without departing from the spirit and scope of the invention, It will be obvious that they fall within the scope of the appended claims.

100: Movable contact 200: Split contact
210: bottom part of hollow part 240:
300: shield 310: first discharge hole
320: shield inner space 330: dome portion
340: side wall 350: third discharge hole
400: conductor container 410: second discharge hole
420: recess 430: incision
44: Gap 45: Wall

Claims (9)

A hollow divided contact which is brought into contact with the movable contact provided on the movable side,
A shield which is formed so as to surround the split contact and has a first discharge hole formed at an upper portion thereof,
A recessed portion to which the split contact and the shield are fixed and a second exhaust hole communicating with the inside of the divided contact at a position corresponding to a lower end of the hollow portion of the split contact, As a result,
Wherein the shield further comprises a plurality of third discharge holes formed in the side wall. The method according to claim 1,
Wherein the third discharge hole is an elongated hole having a long axis formed in a circumferential direction. 3. The method of claim 2,
And the third discharge hole has two to four fastening openings. 3. The method of claim 2,
Wherein a clearance is formed between an outer circumferential surface of the shield and an inner circumferential surface of the conductor container concave portion so that the insulated gas discharged from the third discharge hole is discharged. 5. The method of claim 4,
And a round portion is formed on an outer edge of the third discharge hole. 3. The method of claim 2,
A cut portion is formed in both side walls perpendicular to the axial direction of the conductor container in a wall surface constituting the inner circumferential surface of the concave portion,
And the third discharge hole of the shield is disposed so as to face the cutout portion so that the high-temperature insulating gas is smoothly discharged to both sides of the conductor container through the third discharge hole. 7. The method according to any one of claims 1 to 6,
And the inner diameter of the second discharge hole is equal to the inner diameter of the divided contact. 8. The method of claim 7,
Wherein an angle formed by a straight line contacting the outermost portion of the contact portion of the divided contact point parallel to the axis of the shield and a tangent of the first exit hole is at most 45 degrees. 7. The method according to any one of claims 1 to 6,
Wherein the shield is an integral type shield formed by processing one raw material.
KR2020150002725U 2015-04-27 2015-04-27 Fixed Structre of High Speed Earthing Switch KR200489975Y1 (en)

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KR2020150002725U KR200489975Y1 (en) 2015-04-27 2015-04-27 Fixed Structre of High Speed Earthing Switch

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Application Number Priority Date Filing Date Title
KR2020150002725U KR200489975Y1 (en) 2015-04-27 2015-04-27 Fixed Structre of High Speed Earthing Switch

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KR20160003826U true KR20160003826U (en) 2016-11-04
KR200489975Y1 KR200489975Y1 (en) 2019-09-03

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0614378Y2 (en) * 1988-07-11 1994-04-13 日新電機株式会社 Switcher type switch
KR20090059818A (en) * 2007-12-07 2009-06-11 현대중공업 주식회사 Apparatus for hot gas exhaustion of gas insulation switch

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0614378Y2 (en) * 1988-07-11 1994-04-13 日新電機株式会社 Switcher type switch
KR20090059818A (en) * 2007-12-07 2009-06-11 현대중공업 주식회사 Apparatus for hot gas exhaustion of gas insulation switch

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KR200489975Y1 (en) 2019-09-03

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