KR101440831B1 - Equal pressure apparatus utilized during vacuumming electrical transformer - Google Patents

Equal pressure apparatus utilized during vacuumming electrical transformer Download PDF

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Publication number
KR101440831B1
KR101440831B1 KR1020140057235A KR20140057235A KR101440831B1 KR 101440831 B1 KR101440831 B1 KR 101440831B1 KR 1020140057235 A KR1020140057235 A KR 1020140057235A KR 20140057235 A KR20140057235 A KR 20140057235A KR 101440831 B1 KR101440831 B1 KR 101440831B1
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KR
South Korea
Prior art keywords
main body
valve
cylindrical
hose
cylindrical main
Prior art date
Application number
KR1020140057235A
Other languages
Korean (ko)
Inventor
정재식
Original Assignee
주식회사 청원전력개발
(주) 구주전력
(주) 인덕전력
이레전기 (주)
(주) 인성전력
주식회사 대광전력
주식회사 기선전력
신안전기 주식회사
유한회사 한광전력
(주)인화전력
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Application filed by 주식회사 청원전력개발, (주) 구주전력, (주) 인덕전력, 이레전기 (주), (주) 인성전력, 주식회사 대광전력, 주식회사 기선전력, 신안전기 주식회사, 유한회사 한광전력, (주)인화전력 filed Critical 주식회사 청원전력개발
Priority to KR1020140057235A priority Critical patent/KR101440831B1/en
Application granted granted Critical
Publication of KR101440831B1 publication Critical patent/KR101440831B1/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/23—Corrosion protection
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/42—Circuits specially adapted for the purpose of modifying, or compensating for, electric characteristics of transformers, reactors, or choke coils
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F29/00—Variable transformers or inductances not covered by group H01F21/00
    • H01F29/02—Variable transformers or inductances not covered by group H01F21/00 with tappings on coil or winding; with provision for rearrangement or interconnection of windings

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Housings And Mounting Of Transformers (AREA)

Abstract

An equal pressure apparatus utilized when vacuuming a transformer includes: a cylindrical body with a hollow rectangular inside; a lower support to support and fix the lower portion of the cylindrical body; a handle attached to the outer top surface of the cylindrical body; a pressure sensor attached to the outer top surface of the cylindrical body to measure internal pressure of the cylindrical body; a first body valve to open/close a hose for connecting the cylindrical body to a 1 phase of a transform body; a first OLTC valve to open/close a hose for connecting the cylindrical body to a 1 phase of the tap switch converter; a second body valve to open/close a hose for connecting the cylindrical body to a 2 phase of the transform body; a second OLTC valve to open/close a hose for connecting the cylindrical body to a 2 phase of the tap switch converter; a third body valve to open/close a hose for connecting the cylindrical body to a 3 phase of the transform body; a third OLTC valve to open/close a hose for connecting the cylindrical body to a 3 phase of the tap switch converter; a pressure sensor connection valve provided at a second lateral side of the transformer body to open/close a hose for connecting the cylindrical body to a pressure sensor; and a vacuum pump connection valve provided on a third lateral side of the transformer body to open/close a hose for connecting the cylindrical body to a vacuum pump to make the transformer body to be a vacuum state.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an equalizing pressure equalizing apparatus for use in a vacuum of a transformer,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transformer, and more particularly, to an apparatus and a method for converting a tap switching device and a transformer main body to equal pressure in a case where vacuum is applied to a transformer by using a vacuum pump to inject oil or nitrogen into the transformer, To an equalizing apparatus.

The on-load tap changer (OLTC) is attached to the transformer. The transformer with the tap-changer is also called the on-load tap-changer.

The tap change-over converter is widely used as a transformer of a power distribution substation for adjusting the transforming ratio of a transformer without affecting active power, reactive power, or the like in a state where a current is supplied to a load.

The tap change-over switching device is configured to select and switch the position of the tap by a control switch, and is configured to manually lift and lower the tab of the required voltage.

Registration Practical Utility Model No. 20-0345460 discloses a tap-change converter of such a transformer, and a structure for preventing an accident for preventing malfunction is disclosed. As another example, Korean Utility Model Registration No. 20-0378053 discloses a structure for preventing and protecting the internal explosion of the OLTC.

These transformers operate at high voltage during operation and easily deteriorate. In order to prevent deterioration, insulation technology is mainly applied to prevent deterioration of insulating oil. Therefore, oil or nitrogen is also injected into the transformer to prevent deterioration.

On the other hand, the transformer needs to be closed to remove the internal moisture. In order to remove the internal moisture, the vacuum is mainly used to remove moisture by using a vacuum pump.

As such, the transformer requires devices such as a nitrogen injector, a vacuum pump, etc. for its normal operation and maintenance.

However, in the case of a transformer with a tap-change converter, a single vacuum pump is sequentially connected to the transformer main body and the tap-change converter in order to make them in a vacuum state. Or two vacuum pumps were respectively connected to the transformer main body and the tap change-over converter to make them in a vacuum state.

However, the material of the oil pressure chamber in which the tap-change transducer is placed is usually made of a poly resin or a fiberglass, and can be broken. Since the insulating oil in the oil chamber is contaminated by the arc generated when the tap changer operates, the oil is filtered after tapping to the oil filter unit. If there is a crack on the outer wall of the oil compartment, Which may cause the insulation performance of the transformer to deteriorate.

That is, when the inside of the transformer is made to be in a vacuum state, a vacuum state is established through the hose connected to the tap-changer and the transformer main body respectively by a vacuum pump. In order to make the internal pressure of the transformer and the OLTC equal, In this case, if a failure or an abnormality occurs in the vacuum pump, the vacuum operation must be restarted from the beginning.

In severe cases, cracks may be generated in the oil chamber or the tap-change converter may be destroyed by pressure. Therefore, a method for making the pressure of the transformer main body and the tap-change converter constant is required.

20-0345460 20-0378053

SUMMARY OF THE INVENTION It is an object of the present invention to provide an equalization apparatus for equalization utilized in the vacuum of a transformer.

According to an aspect of the present invention, there is provided an equalizer for equalizing a transformer, comprising: a cylindrical main body having a rectangular hollow inside; A lower pedestal supporting and fixing the lower portion of the cylindrical body; A handle attached to an upper outer surface of the cylindrical body; A pressure sensor attached to an upper outer surface of the cylindrical body to measure an inner pressure of the cylindrical body; A first body valve provided on a first longitudinal side of the cylindrical body for opening and closing a hose interconnecting the cylindrical body and one phase of the transformer body; A first OLTC valve provided on a first side surface of the cylindrical body for opening and closing a hose that interconnects one phase of the cylindrical main body and an on-load tap changer (OLTC); A second body valve provided on a first side surface in the longitudinal direction of the cylindrical body for opening and closing a hose interconnecting the cylindrical body and the two phases of the transformer body; A second OLTC valve provided on a first side surface of the cylindrical body for opening and closing a hose that interconnects the two main bodies of the tubular body and the tap-change transducer; A third body valve provided on a second side surface in the longitudinal direction of the cylindrical body for opening / closing a hose connecting the cylindrical body and the transformer main body; A third OLTC valve provided on a second side surface of the cylindrical body for opening and closing a hose that interconnects the three main phases of the cylindrical body and the tap-change transducer; A pressure sensor connection valve provided on a second side surface of the cylindrical body for opening and closing a hose that interconnects the cylindrical body and the pressure sensor; And a vacuum pump connection valve provided on a third side of the cylindrical body to open and close the hose connecting the cylindrical body and the vacuum pump for bringing the cylindrical body into a vacuum state.

Here, it may be configured to further include a nitrogen supply passage connecting valve provided on the second side of the cylindrical body to open and close the hose connecting the cylindrical main body and the nitrogen supply passage for supplying nitrogen to the transformer main body .

According to the equipotential equalizing device used in vacuum of the above-mentioned transformer, the equipotential equalizing device connected to the vacuum pump is connected to the transformer main body and the tap change-over transducer by a hose so that both devices are lowered to the same pressure to create a vacuum state The internal pressure of the transformer main body and the internal pressure of the tap-change transducer are different from each other. Further, there is an effect that breakage of the tap-change conversion device can be prevented.

In addition, even when nitrogen is injected for preventing deterioration, the internal pressure of the transformer main body and the tap-change conversion device are maintained at the same level, thereby preventing cracks in the oil compartment and preventing damage to the tap- .

FIG. 1 is a block diagram illustrating a connection state of an equalizing equalizer and a peripheral device used in a vacuum of a transformer according to an embodiment of the present invention. Referring to FIG.
FIG. 2 is a perspective view of an equalizer for equalizing a transformer used in a vacuum according to an embodiment of the present invention. Referring to FIG.
FIG. 3 is a plan view of an equality apparatus for equalization utilized in vacuum of a transformer according to an embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail to the concrete inventive concept.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Like reference numerals are used for like elements in describing each drawing.

The terms first, second, A, B, etc. may be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, .

On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise.

In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram illustrating a connection state of an equalizing equalizer and a peripheral device used in a vacuum of a transformer according to an exemplary embodiment of the present invention. Referring to FIG.

Referring to FIG. 1, an equality equalizing device 101 (hereinafter referred to as an "equalizing equalizing device") 101 used for vacuuming the present transformer is connected to a transformer main body 10 and a tap switching converter 20 Respectively.

The equipotential equalizing apparatus 100 includes a nitrogen supply cylinder 200 for supplying nitrogen to the transformer main body 10 and the tap-changer 20, a transformer main body 10 and a tap-change converter 20, To the vacuum pump 300 to make the vacuum pump 300 a vacuum state.

The equipotential equalizing apparatus 100 makes the transformer main body 10 and the tap changer 20 to vacuum in order to remove the internal moisture of the transformer main body 10 and the tap changer 20. The internal pressure of the transformer main body 10 and the internal pressure of the tap changer 20 And the internal pressure is maintained at a constant value, respectively.

Thus, the outer tube of the tap-change transducer 20 is prevented from being ruptured or distorted due to mutual pressure difference, and the tap-change transducer is not broken even when the pressure difference is large.

In addition, nitrogen is injected into the nitrogen supply cylinder 200 through the equalizer 100 even when nitrogen is injected into the transformer main body 10 and the tap-change converter 20 to prevent deterioration, It is possible to prevent the outer tube of the tap-changer 20 from being damaged or destroyed by keeping the nitrogen pressures of the main body 10 and the tap-changer 20 constant.

FIG. 2 is a perspective view of an equality equalizing apparatus for use in a vacuum of a transformer according to an embodiment of the present invention, and FIG. 3 is a plan view of an equality equalizing apparatus for use in vacuum of a transformer according to an embodiment of the present invention.

2 and 3, an equalizer 100 for use in vacuum of a transformer according to an embodiment of the present invention includes a cylindrical body 101, a lower pedestal 102, a handle 103, a pressure sensor A first main body valve 104, a first main valve 105, a first main body valve 106, a second main body valve 107, a second main body valve 108, a third main body valve 109, A pressure sensor connection valve 111, a vacuum pump connection valve 112, and a nitrogen supply passage connection valve 113. As shown in Fig.

Hereinafter, the detailed configuration will be described.

The cylindrical main body 101 may have a rectangular shape and may have a hollow interior.

The cylindrical main body 101 is preferably made of a metal material.

The lower pedestal 102 can be configured to support and fix the lower portion of the cylindrical main body 101.

The lower pedestal 102 may be provided at a lower portion of the cylindrical main body 101, and it is preferable that wheels are provided in contact with the bottom surface.

And can be configured to facilitate the movement of the cylindrical main body 101 by using the wheels of the lower pedestal 102.

The handle 103 may be attached to the outer surface of the upper portion of the cylindrical main body 101. It is preferable that at least two or more of the handle 103 are provided in consideration of the size of the cylindrical main body 101. [

The pressure sensor 104 may be attached to the upper outer surface of the cylindrical main body 101 and configured to measure the inner pressure of the cylindrical main body 101. The pressure sensor 104 is configured to measure the internal pressure of the cylindrical main body 101 in real time. The pressure sensor 104 may be equipped with a scale and a needle for displaying a measurement value so that the user can visually confirm the pressure.

The first body valve 105 is configured to open and close a hose for interconnecting one phase of the cylindrical main body 101 and the transformer main body 10 and is provided on the first side in the longitudinal direction of the cylindrical main body 101 . Here, since a three-phase transformer is mainly used as the transformer, the hose may be connected to the first, second, and third phases of the transformer main body 10, respectively.

The first OLTC valve 106 has a structure for opening and closing a hose for interconnecting one phase of the cylindrical main body 101 and the on-load tap changer (OLTC) 11, And may be configured to be provided on the first side.

The second body valve 107 is configured to open and close the hose that interconnects the two phases of the cylindrical main body 101 and the transformer main body 10 and is configured to be provided on the first side in the longitudinal direction of the cylindrical main body 101 .

The second OLTC valve 108 is configured to open and close a hose that interconnects the two phases of the cylindrical main body 101 and the tap change-over switching device 11 and is configured to be provided on the first side of the cylindrical main body 101 .

The third body valve 109 is configured to open and close the hose that interconnects the three phases of the cylindrical main body 101 and the transformer main body 10 and is configured to be provided on the second side in the longitudinal direction of the cylindrical main body 101 .

The third OLTC valve 110 is configured to open and close the hose that interconnects the three phases of the cylindrical main body 101 and the tap change-over converter 11 and is configured to be provided on the second side of the cylindrical main body 101 .

The first body valve 105 and the first OLTC valve 106 associated with one phase of the transformer main body 10 can be opened and closed in the same manner and the second body valve 107 and The second OLTC valve 108 can be opened and closed in the same manner and the third body valve 109 and the third OLTC valve 110 related to the three phases can be opened and closed in the same manner.

The pressure sensor connection valve 111 may be configured to be provided on the second side surface of the cylindrical main body 101 for opening and closing the hose connecting the cylindrical main body 101 and the pressure sensor 104.

The vacuum pump connection valve 112 is configured to open and close the hose connecting the cylindrical main body 101 and the vacuum pump 200 for making the cylindrical main body 101 in a vacuum state, And can be configured to be provided on the side surface.

The nitrogen supply passage connecting valve 113 is configured to open and close the hose connecting the cylindrical main body 101 and the nitrogen supply cylinder 300 for supplying nitrogen to the transformer main body 10, And the second side surface of the second substrate.

Here, the opening and closing operations of the vacuum pump connecting valve 112 and the feeding and feeding passage connecting valve 113 can be reversed, respectively.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the following claims. There will be.

10: Transformer main body 20: Tap switching converter
110: cylinder body 102: lower pedestal
103: handle 104: pressure sensor
105: first main valve 106: first OLTC valve
107: second body valve 108: second OLTC valve
109: Third body valve 110: Third OLTC valve
111: Pressure sensor connection valve 112: Vacuum pump connection valve
113: Nitrogen feed cylinder connection valve

Claims (2)

A cylindrical main body 101 in which a rectangular interior is empty;
A lower pedestal 102 for supporting and fixing the lower portion of the cylindrical main body 101;
A handle 103 attached to an upper outer surface of the cylindrical main body 101;
A pressure sensor (104) attached to an upper outer surface of the cylindrical main body (101) to measure the internal pressure of the cylindrical main body (101);
A first body valve 105 provided on a first side in the longitudinal direction of the cylindrical main body 101 for opening and closing a hose that interconnects the cylindrical main body 101 and one surface of the transformer main body 10, ;
A first OLTC provided on the first side surface of the cylindrical main body 101 for opening and closing a hose interconnecting one of the cylindrical main body 101 and the on-load tap changer (OLTC) A valve 106;
A second body valve (107) provided on a first side of the cylindrical body (101) in the longitudinal direction for opening and closing a hose interconnecting the two sides of the cylindrical body (101) and the transformer main body (10);
A second OLTC valve (108) provided on a first side surface of the cylindrical main body (101) for opening and closing a hose interconnecting the two surfaces of the cylindrical main body (101) and the tap change - over transducer (11);
A third body valve 109 provided on a second side surface in the longitudinal direction of the cylindrical body 101 for opening and closing a hose interconnecting the three sides of the cylindrical body 101 and the transformer body 10;
A third OLTC valve 110 provided on a second side surface of the cylindrical main body 101 for opening and closing a hose interconnecting the three main phases of the cylindrical main body 101 and the tap-change transducer 11;
A pressure sensor connection valve 111 provided on a second side surface of the cylindrical main body 101 for opening and closing a hose connecting the cylindrical main body 101 and the pressure sensor 104;
A vacuum pump connecting valve provided on a third side of the cylindrical main body 101 for opening and closing a hose connecting the cylindrical main body 101 and the vacuum pump 200 for bringing the cylindrical main body 101 into a vacuum state, (112). ≪ / RTI >
The method according to claim 1,
And a nitrogen supply pipe provided on the second side of the cylindrical body 101 for opening and closing a hose connecting the cylindrical body 101 and the nitrogen supply cylinder 300 for supplying nitrogen to the transformer body 10. [ Further comprising a connection valve (113). ≪ Desc / Clms Page number 24 >
KR1020140057235A 2014-05-13 2014-05-13 Equal pressure apparatus utilized during vacuumming electrical transformer KR101440831B1 (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101586393B1 (en) * 2015-09-21 2016-01-19 한국메가와트(주) Equal pressure apparatus utilized during vacuuming electrical transformer
KR20210092457A (en) * 2020-01-16 2021-07-26 현대일렉트릭앤에너지시스템(주) Pressure rising simulator of transformer

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0710918U (en) * 1993-07-15 1995-02-14 株式会社明電舎 Incombustible transformer
KR200345460Y1 (en) * 2003-11-14 2004-03-18 한국전력공사 Controller for changing tap of an OLTC
KR200378053Y1 (en) * 2004-12-16 2005-03-14 현대중공업 주식회사 OLTC fitting structure of gas insulated transformer
KR100893179B1 (en) * 2007-10-18 2009-04-17 주식회사 효성 Gas insulated transformer and on load tab changer thereof

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0710918U (en) * 1993-07-15 1995-02-14 株式会社明電舎 Incombustible transformer
KR200345460Y1 (en) * 2003-11-14 2004-03-18 한국전력공사 Controller for changing tap of an OLTC
KR200378053Y1 (en) * 2004-12-16 2005-03-14 현대중공업 주식회사 OLTC fitting structure of gas insulated transformer
KR100893179B1 (en) * 2007-10-18 2009-04-17 주식회사 효성 Gas insulated transformer and on load tab changer thereof

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101586393B1 (en) * 2015-09-21 2016-01-19 한국메가와트(주) Equal pressure apparatus utilized during vacuuming electrical transformer
KR20210092457A (en) * 2020-01-16 2021-07-26 현대일렉트릭앤에너지시스템(주) Pressure rising simulator of transformer
KR102344419B1 (en) * 2020-01-16 2021-12-28 현대일렉트릭앤에너지시스템(주) Pressure rising simulator of transformer

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