CN1244283A - Axial air-cooling of transformers - Google Patents
Axial air-cooling of transformers Download PDFInfo
- Publication number
- CN1244283A CN1244283A CN98801964A CN98801964A CN1244283A CN 1244283 A CN1244283 A CN 1244283A CN 98801964 A CN98801964 A CN 98801964A CN 98801964 A CN98801964 A CN 98801964A CN 1244283 A CN1244283 A CN 1244283A
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- CN
- China
- Prior art keywords
- winding
- power transformer
- transformer
- cable
- air
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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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
- H01F27/08—Cooling; Ventilating
- H01F27/085—Cooling by ambient air
-
- 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
- H01F27/08—Cooling; Ventilating
-
- 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
- H01F27/28—Coils; Windings; Conductive connections
- H01F27/32—Insulating of coils, windings, or parts thereof
- H01F27/322—Insulating of coils, windings, or parts thereof the insulation forming channels for circulation of the fluid
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Coils Of Transformers For General Uses (AREA)
- Transformer Cooling (AREA)
- Insulated Conductors (AREA)
- Coils Or Transformers For Communication (AREA)
- Motor Or Generator Cooling System (AREA)
Abstract
A power transformer(1)comprising a transformer core wound with a high-voltage cable, which is composed of a core having a plurality of strand parts (112), an inner semiconducting layer(113)surrounding the core, an insulating layer(114)surrounding the inner semiconducting layer(113), and an outer semiconducting layer(115)surrounding the insulating layer(114)wherein the winding is provided with spacers(4, 12)arranged to separate each cable turn in radial direction in the winding in order to create axial cylindrical cooling ducts(3).
Description
The present invention relates to a kind of air cooled, conductor winding power transformer, and relate to the method that a kind of air cooling conductor twines power transformer.
The modern electric transformer is normally oil cooled.The iron core and all windings (elementary, secondary, control) that comprise a plurality of pillars unshakable in one's determination that connected by yoke are immersed in the closed container that oil is housed.The heat that produces in coil and iron core is removed by the oil of inner coils and circulation unshakable in one's determination, and oil outwards is recycled to wherein the external unit that it is cooled.The oil circulation can be forced to carry out, the suction oil ring around, perhaps can carry out naturally, produce by temperature difference in the oil.The oil of circulation is externally by being used for the cooling of air cooling or water-cooled device.The extraneous air cooling can be forced to carry out, or realizes by free convection.Transmit the agent except that it plays heat, oil also has insulation function being used for the oil cooled transformer of high pressure.
Dry-type transformer is normally air cooled.They are usually by the free convection cooling, because current dry-type transformer is used under the low electrical load.Present technique relates to as at GB1,147, the axial cooling duct of describing in 049 by means of the generation of ripple winding, be used for cooling off the axial pipe that is embedded in the winding in the casting resin as described in the EP 83107410.9, and under peak load the use of cross-flow fan as described in the SE 7303919-0.
The cooling of twining power transformer for conductor is had relatively high expectations.Forced convertion is essential, to satisfy the cooling requirement in all windings.Free convection is not enough to the cooling conductor winding.Article one, the very short route that is used for heat is passed to cooling agent is important, and the important cooling agent that is delivered to efficiently in addition.Therefore importantly, all windings directly contact with the cooling agent of q.s.
Learn a kind of conductor by US 5 036 165, wherein insulating barrier is equipped with in one and an outer semiconductor pyrolysis glass layer.Also know, conductor in motor generator is equipped with a kind of like this insulating barrier, for example as described in US 5 066 881, wherein semiconductor pyrolysis glass layer contacts with two parallel bars that form conductor, and the insulating barrier in the stator slot is surrounded by an outer semiconductor pyrolysis glass layer.The pyrolysis glass fiber material of describing is suitable, even because it also can keep its resistivity after impregnation process.
The objective of the invention is to, a kind of device according to these claims is provided, promptly have the type of in preamble, describing, can air cooling comprise that the cable of describing the high-pressure conductor of type described in the part twines power transformer.In first embodiment, the objective of the invention is in winding, produce between every circle winding axial cylindrical shape conduit, the cooling agent that wherein correctly distributes is to satisfy the difference cooling requirement of winding.During twining, coil produces cylindrical conduit by inserting separator.Realize flow of coolant with fan, and the size of definite separator, to provide by the flowing of conduit, all conduits will satisfy the cooling requirement of each winding.
The present invention relates to a kind of power transformer that is wound with the transformer core of cable that comprises, be arranged to winding the separator of radially isolating each cable circle in winding is housed, so that produce axial cylindrical shape conduit.
The first embodiment of the present invention thereby comprise axial cylindrical shape cooling duct between each winding turns of self settling, described conduit produces by inserting separator during coil twines.Cylindrical conduit also is arranged in pillar unshakable in one's determination and between the ground floor of the nearest cable of iron core.This embodiment also comprises the fan that is used for by axial cylindrical shape conduit transmission air.Determine the size of separator in the conduit, providing the resistance of variation, the flow of cooling agent that distributes thus, thus satisfy cooling requirement in each axial pipe, be different because require for all winding coolings.Although " air " is described as cooling agent, other gaseous coolants also are suitable for, for example the helium cooling agent.
In power transformer according to the present invention, winding is made up of the cable that has solid, extruding insulation thing that has with being used for distribution now, for example XLPE cable or have the cable of EPR insulant.A kind of like this cable comprises an inner wire of being made up of one or more strands of parts, and an inner semiconductor layer is round this conductor, and a solid insulating layer inner semiconductor layer, and an outer semiconductor layer is round insulating barrier.Such cable is flexible, and this is a kind of important properties in this context, because be used for technology according to device of the present invention, and the main winding system that forms by the cable of deflection between erecting stage based on winding wherein.XLPE cable flexible usually for the cable of 30 millimeters of diameters corresponding to about 20 centimetres bending radius, and for the cable of 80 millimeters of diameters, bending radius is about 65 centimetres.In this application, term " flexible " is used to refer to low to four times of cable size magnitudes, and preferably eight of cable size to duodenary bending radius and flexible winding.
Winding among the present invention should be built into and can keep its characteristic, even also be like this when its is crooked and when being subjected to thermal stress during operation.In this context importantly all layer keep it bonded to one another.All layer material character, particularly its elasticity and the relatively hot coefficient of expansion here are conclusive.In XLPE cable, for example, insulating barrier comprises crosslinked, low density polyethylene (LDPE), and all semiconductor layers are made up of the polyethylene that is blended in wherein by carbon black and metallic particles.Change in volume as the temperature fluctuation result, variation as the cable radius is absorbed fully, and, do not lose the bonding between all layers so can radial expansion take place because thermal coefficient of expansion has smaller difference with respect to the elasticity of these materials in all layers.
The above-mentioned material combination should only be considered as an example.Other are realized rated condition, (promptly have 10 as semi-conductive condition in addition
-1-10
6Ohm-cm, for example resistivity in 1-500 ohm-cm or the 10-200 ohm-cm scope) combination also fall within the scope of the present invention naturally.
For example, insulating barrier can be made up of following material, solid thermoplastic material such as low density polyethylene (LDPE) (LDPE), high density polyethylene (HDPE) (HDPE), polypropylene (PP), polybutene (PB), polymethylpentene (PMP), cross-linked material such as crosslinked polyethylene (XLPE), or the rubber such as ethylene-propylene rubber (EPR) or silicon rubber.
Interior can have identical basic material with outer semiconductor layer, but have the conducting material granule such as carbon black or metal dust to be blended in wherein.
The engineering properties of these materials, particularly its thermal coefficient of expansion, be subjected to carbon black or metal dust whether be blended in wherein influence less-ratio to require at least, to realize according to conductivity required in this invention.Insulating barrier and semiconductor layer thereby have essentially identical thermal coefficient of expansion.
Vinyl-vinyl acetate copolymer/nitrile rubber, butyl grafted polyethylene, ethylene-butyl acrylate copolymer and ethylene-ethyl acrylate copolymer also can be configured for the suitable copolymer of semiconductor layer.Even, wish that also its thermal coefficient of expansion is basic identical when different kind of material during as basic in each layer.This is the situation about combination of materials listed above.
Material listed above has elasticity preferably, has E＜500MPa, the E modulus of best＜200MPa.This elasticity is enough to radially be absorbed flexible, thereby crackle or other damages can not occur for any less difference between the material coefficient of thermal expansion coefficient in all layers, thereby and all layers can be not separated from one another.Material in all layers is flexible, and the cohesive force between all layers the numerical value with material the weakest point is identical at least.
The conductivity of two semiconductor layers is enough to make basically current potential to equate along every layer.Big must being enough to of the conductivity of outer semiconductor layer is enclosed in electric field in the cable, and low as to be enough to can not cause remarkable loss owing to the electric current of layer longitudinal induction.
Thereby each of two semiconductor layers constitutes an equipotential surface basically, and these layers will be enclosed in the electric field between them substantially.Certainly, there is not anything to prevent that one or more semiconductor-assisted layers are arranged in the insulating barrier.
Referring now to accompanying drawing, the present invention will be described in more detail.
Fig. 1 represents embodiment according to a kind of power transformer of the present invention with stereogram.
Fig. 2 a is illustrated in the view of seeing from the winding top that has cooling duct, separator and outer cover according in the first embodiment of the present invention.
Fig. 2 b is illustrated in the end view that every tool coil among Fig. 2 a is equipped with the embodiment of a fan.
Fig. 3 represents the cross section according to the coil of embodiment among Fig. 1, and its axial pipe is between winding.
Fig. 4 represents the cross section according to a kind of high-tension cable of the present invention.
Fig. 1 represents one embodiment of the present of invention, relates to a kind of power transformer 1 that three winding coils 2 are housed, and each winding coil has a plurality of windings, and winding is arranged to all circles of winding is radially isolated by axial isolation part 4, so that cooling duct 3 with one heart to be provided axially.Transformer is equipped with an iron core in a usual manner.
Fig. 2 a represents the view seen from the top of the three-phase power transformer 1 that the winding 2 that constitutes coil is housed, produces cooling duct 3 between the circle by each that extends axially that separator 4 is placed in winding radially placed.Distribution between the separator 4 in the embodiment shown is such, obtains six separators in every concentric cooling duct 3.From the cooling aspect, the material of separator and shape importance are little.Shape, quantity and the material of separator determined in the machinery of transformer, magnetic and electric aspect.This figure goes back the yoke 5 of indication transformer, and this yoke constitutes the part of transformer core.The yoke of representing with the cross section has its vertical cooling duct 6 of indication.Each winding coil also by one within it portion arrange fan conduit 7 that cooling air flows round.It is different requiring for all winding coolings, this means the cooling flow difference in concentric cold conduit.In order to realize the correct distribution of cooling agent, all conduits radially are being of different sizes, so that in conduit, provide different resistances, and thereby according to the distribute traffic that needs of conduit.Have the conduit of less cooling requirement thereby have less radial distance than having the conduit that bigger cooling requires, therefore a kind of conduit in back has bigger radial distance.The cable of describing in the present embodiment twines transformer, between the low-voltage winding winding of close iron core () than between the high pressure winding, having bigger gap.
The end view of power transformer among Fig. 2 b presentation graphs 2a is equipped with corresponding windings and a corresponding yoke 5, and yoke 5 forms unshakable in one's determination with its three pillars 8.Fan conduit 7 is at an end of coil, and the fan guard 9 of at least one fan 10 is wherein installed in formation.Embodiment among the figure represents three fans, seals with respect to its each coil, so that produce air-flow in axial cylindrical shape cooling duct 3.Coil is enclosed in the cylinder blanket 11, and preventing the radial leakage of air, and the guiding air shaft is to passing through coil.Produce an outer catheter that is used for cooling off the exterior portion of outermost cable winding around the shell 11 of outermost cable winding.In this embodiment, fan of each coil installation also is obvious.Can deflate or force air to pass coil from coil by each fan 10.Fan the fan conduit 7 of 10 sides at coil apparent wind, for the suction of foundation fan and pressurization and flow into or the air that flows out is opened fully.Fan conduit 7 at fan side has the opening with respective action.
Fig. 3 represents the cross section of a coil, and axial cylindrical shape cooling duct 3 is at each radially between the winding 2.Separator also is arranged at the pillar 8 of iron core and forms an axial cooling duct between the winding of close iron core.Cooling duct is produced by the separator that is placed between the winding, sees Fig. 2 a.Separator is settled around circular cross section, and is extending axially.In winding around, separator is placed between all circles of winding.Arrow indication among the figure is by the air-flow of coil windings.Air can flow in either direction, and this depends on suction or pressure effect.
Fig. 4 represents the cutaway view as the high-tension cable 111 of Transformer Winding according to the present invention.High-tension cable 111 comprises a plurality of copper (Cu) thighs 112 that for example have circular cross section.These strands 112 are arranged in the middle part of high-tension cable 111.Around thigh 112 are one first semiconductor layers 113.Around first semiconductor layer 113 is an insulating barrier 114, for example XLPE insulant.Around insulating barrier 114 are one second semiconductor layers 115.Notion in this application " high-tension cable ", thereby do not comprise the overcoat that centers on such cable that is used for distribution usually.High-tension cable has diameter and the conductive area in 40-3000 square millimeter scope in 20-250 millimeter scope.
The example that the invention is not restricted to represent.Several within the scope of the present invention modifications are feasible.For example, needn't provide a fan for each coil.Have a layout of enough air being supplied with the fan of all three coils.Can suck air or force, so that realize the cooling wished by coil.Similarly, the quantity of separator and its shape are not fixed, and the distortion of several different separator is possible, to realize correct cooling.Separator needn't extend axially whole in first embodiment that describes, and can settle in several modes.
Another kind improves, and arranges the fan speed control by means of temperature sensor, so that realize the cooling requirement of variation according to the load in the transformer.
Shell also can be arranged by the multiple mode except that shown in the foregoing description.The outermost cable winding can be used as shell body, and by means of the free convection cooling outside.
Claims (14)
1. power transformer (1) that comprises a transformer core, it is characterized in that, iron core is wound with a cable, and cable is a high-tension cable (111), high-tension cable (111) comprises the core (112) that has the multiply part, an inner semiconductor layer (113) is around this core, an insulating barrier (114) is round inner semiconductor layer (113), and an outer semiconductor layer (115) is round insulating barrier (114), and winding is equipped with separator (4,12), separator (4,12) be arranged to each cable circle of radially isolation in winding, so that produce an axial cylindrical shape cooling duct (3).
2. power transformer according to claim 1 is characterized in that separator (4,12) is disposed axially between every circle of winding.
3. power transformer according to claim 2 is characterized in that at least six separators (4) distribute around the pillar (8) of transformer equably.
4. according to the described power transformer in the arbitrary top of claim 1-3, it is characterized in that Transformer Winding is equipped with a fan guard (9), fan guard (9) is with respect to the end sealing of the outermost turn of winding, fan guard (9) is gone up and is connected a fan (10), and fan (10) is arranged to force the gas such as air to pass through, perhaps aspirate the gas such as air, air from all circles of winding axially to transformer core (8).
5. according to the described power transformer in the arbitrary top of claim 1-4, it is characterized in that high-tension cable (111) has diameter and the conductive area in 40-3000 square millimeter interval in 20-250 millimeter interval.
6. according to the described power transformer in the arbitrary top of claim 1-5, it is characterized in that high-tension cable (111) is flexible, and all layers are adjacent to each other also.
7. according to the described power transformer in the arbitrary top of claim 1-6, it is characterized in that described layer is made up of the material with such elasticity and such thermal coefficient of expansion, thereby change in volume can be absorbed by the elasticity of material in the layer that is caused by temperature fluctuation during operation, thus when temperature fluctuation occurring during operation all layer keep it bonded to one another.
8. according to the described power transformer in the arbitrary top of claim 1-7, it is characterized in that the material of described layer has high resiliency, have less than the modulus of elasticity of 500MPa better, best less than 200MPa.
9. according to the described power transformer in the arbitrary top of claim 1-8, it is characterized in that the material coefficient of thermal expansion coefficient is basic identical in the described layer.
10. according to the described power transformer in the arbitrary top of claim 1-9, it is characterized in that the cohesive force between all layers has identical with the weakest point of material at least numerical value.
11., it is characterized in that equipotential surface of each semiconductor layer basic comprising according to the described power transformer in the arbitrary top of claim 1-10.
12. the air cooling method of the power transformer that each cable of the above claim of basis twines, it is characterized in that at least one fan (10) along the surface of transformer core pillar (8) and axially between every circle of winding forced air flow or suction air.
13. method according to claim 12 is characterized in that during the winding of transformer separator (4) being inserted between the winding turns.
14. method according to claim 13, the speed that it is characterized in that temperature sensor control fan is to produce suitable air-flow.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE9700338A SE511360C2 (en) | 1997-02-03 | 1997-02-03 | Air-cooled cable-wound power transformer |
| SE9700338-8 | 1997-02-03 | ||
| SE9704414A SE9704414D0 (en) | 1997-02-03 | 1997-11-28 | Axial air cooling and transformer |
| SE9704414-3 | 1997-11-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1244283A true CN1244283A (en) | 2000-02-09 |
Family
ID=26662864
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN98801964A Pending CN1244283A (en) | 1997-02-03 | 1998-02-02 | Axial air-cooling of transformers |
Country Status (14)
| Country | Link |
|---|---|
| EP (1) | EP1016098A1 (en) |
| JP (1) | JP2001509959A (en) |
| KR (1) | KR20000070417A (en) |
| CN (1) | CN1244283A (en) |
| AU (1) | AU724972B2 (en) |
| BR (1) | BR9807134A (en) |
| CA (1) | CA2276620A1 (en) |
| EA (1) | EA001869B1 (en) |
| NO (1) | NO993673D0 (en) |
| NZ (1) | NZ337098A (en) |
| PL (1) | PL334617A1 (en) |
| SE (1) | SE9704414D0 (en) |
| TR (1) | TR199901700T2 (en) |
| WO (1) | WO1998034238A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103354150A (en) * | 2013-08-01 | 2013-10-16 | 南通市海王电气有限公司 | Novel dry-type transformer |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10137518C1 (en) | 2001-07-30 | 2003-04-24 | Siemens Ag | Electrical winding arrangement |
| US7205875B2 (en) * | 2003-06-26 | 2007-04-17 | Eaton Power Quality Corporation | Hybrid air/magnetic core inductor |
| KR100802627B1 (en) * | 2004-05-12 | 2008-02-14 | 주식회사 오.엘.티 | Oil forced cooling apparatus for oil type high voltage transformer |
| KR101031589B1 (en) * | 2009-03-25 | 2011-04-27 | 현대종합금속 주식회사 | Electric transformer |
| JP5717426B2 (en) * | 2010-12-03 | 2015-05-13 | 株式会社東芝 | Static induction machine |
| ES2530055T3 (en) * | 2011-02-16 | 2015-02-26 | Abb Technology Ag | Cooling system for dry transformers |
| US8368497B2 (en) * | 2011-03-17 | 2013-02-05 | Hamilton Sundstrand Corporation | Transformer assembly with enhanced air cooling |
| JP5835604B2 (en) * | 2011-03-31 | 2015-12-24 | 株式会社ダイヘン | Dry transformer |
| JP2013004776A (en) * | 2011-06-17 | 2013-01-07 | Hitachi Industrial Equipment Systems Co Ltd | Mold transformer |
| KR101290682B1 (en) | 2011-11-01 | 2013-07-29 | 신성공업주식회사 | Transformer having cooling device |
| RU168099U1 (en) * | 2016-06-16 | 2017-01-18 | Публичное акционерное общество "Транснефть" (ПАО "Транснефть") | Three-phase multi-winding transformer with a closed air cooling system |
| RU181145U1 (en) * | 2017-10-30 | 2018-07-05 | Публичное акционерное общество "Транснефть" (ПАО "Транснефть") | POWER TRANSFORMER WITH TWISTED MAGNETIC WIRE |
| CN117219407B (en) * | 2023-10-31 | 2024-05-31 | 深圳市百恒电气有限公司 | Dry-type transformer cooling device and cooling method thereof |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2295415A (en) * | 1940-08-02 | 1942-09-08 | Westinghouse Electric & Mfg Co | Air-cooled, air-insulated transformer |
| US5036165A (en) * | 1984-08-23 | 1991-07-30 | General Electric Co. | Semi-conducting layer for insulated electrical conductors |
| US5066881A (en) * | 1984-08-23 | 1991-11-19 | General Electric Company | Semi-conducting layer for insulated electrical conductors |
-
1997
- 1997-11-28 SE SE9704414A patent/SE9704414D0/en unknown
-
1998
- 1998-02-02 EA EA199900703A patent/EA001869B1/en not_active IP Right Cessation
- 1998-02-02 KR KR1019997006652A patent/KR20000070417A/en not_active Application Discontinuation
- 1998-02-02 JP JP53279798A patent/JP2001509959A/en active Pending
- 1998-02-02 EP EP98902352A patent/EP1016098A1/en not_active Withdrawn
- 1998-02-02 CN CN98801964A patent/CN1244283A/en active Pending
- 1998-02-02 NZ NZ337098A patent/NZ337098A/en unknown
- 1998-02-02 PL PL98334617A patent/PL334617A1/en unknown
- 1998-02-02 TR TR1999/01700T patent/TR199901700T2/en unknown
- 1998-02-02 BR BR9807134-3A patent/BR9807134A/en not_active IP Right Cessation
- 1998-02-02 CA CA002276620A patent/CA2276620A1/en not_active Abandoned
- 1998-02-02 WO PCT/SE1998/000155 patent/WO1998034238A1/en not_active Application Discontinuation
- 1998-02-02 AU AU58906/98A patent/AU724972B2/en not_active Ceased
-
1999
- 1999-07-28 NO NO993673A patent/NO993673D0/en not_active Application Discontinuation
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103354150A (en) * | 2013-08-01 | 2013-10-16 | 南通市海王电气有限公司 | Novel dry-type transformer |
Also Published As
| Publication number | Publication date |
|---|---|
| SE9704414D0 (en) | 1997-11-28 |
| TR199901700T2 (en) | 1999-09-21 |
| PL334617A1 (en) | 2000-03-13 |
| AU724972B2 (en) | 2000-10-05 |
| JP2001509959A (en) | 2001-07-24 |
| WO1998034238A1 (en) | 1998-08-06 |
| EA001869B1 (en) | 2001-10-22 |
| EA199900703A1 (en) | 2000-04-24 |
| CA2276620A1 (en) | 1998-08-06 |
| AU5890698A (en) | 1998-08-25 |
| EP1016098A1 (en) | 2000-07-05 |
| NO993673L (en) | 1999-07-28 |
| BR9807134A (en) | 2000-01-25 |
| NO993673D0 (en) | 1999-07-28 |
| NZ337098A (en) | 2001-06-29 |
| KR20000070417A (en) | 2000-11-25 |
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| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |