EP2131371A1 - Traversée haute tension, dispositif haute tension comprenant ladite traversée et procédé de refroidissement - Google Patents

Traversée haute tension, dispositif haute tension comprenant ladite traversée et procédé de refroidissement Download PDF

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Publication number
EP2131371A1
EP2131371A1 EP08157484A EP08157484A EP2131371A1 EP 2131371 A1 EP2131371 A1 EP 2131371A1 EP 08157484 A EP08157484 A EP 08157484A EP 08157484 A EP08157484 A EP 08157484A EP 2131371 A1 EP2131371 A1 EP 2131371A1
Authority
EP
European Patent Office
Prior art keywords
bushing
high voltage
conductor
heat sink
cooling
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.)
Withdrawn
Application number
EP08157484A
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German (de)
English (en)
Inventor
Kerstin Ekeroth Reijm
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ABB Technology AG
Original Assignee
ABB Technology AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by ABB Technology AG filed Critical ABB Technology AG
Priority to EP08157484A priority Critical patent/EP2131371A1/fr
Priority to CNA2008101264711A priority patent/CN101599326A/zh
Priority to CN2009201503089U priority patent/CN201514824U/zh
Priority to DE200920007819 priority patent/DE202009007819U1/de
Publication of EP2131371A1 publication Critical patent/EP2131371A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B17/00—Insulators or insulating bodies characterised by their form
    • H01B17/54—Insulators or insulating bodies characterised by their form having heating or cooling devices
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B17/00—Insulators or insulating bodies characterised by their form
    • H01B17/26—Lead-in insulators; Lead-through insulators

Definitions

  • the present invention relates to the field of high voltage power systems, and in particular to high voltage bushings used in high voltage devices forming parts of such systems.
  • high voltage equipment and devices e.g. high voltage transformers, reactors, switchgear etc.
  • a grounded barrier e.g. a wall or an enclosure of the electric device such as a transformer tank.
  • Conventional high voltage bushings comprise an insulator made of ceramic or composite material, which is normally provided with sheds and which is generally hollow.
  • voltage grading is performed by a condenser core or some other type of voltage grading device, through which an electrical conductor passes.
  • the electrical conductor connects one side of the bushing, where a high voltage electric device is connected, with the other side of the bushing where another electric device is connected.
  • the first electric device is a transformer
  • the bushing is fitted on the transformer enclosure and the conductor of the bushing connects the inside of the transformer with the outside, where another electric device can be connected, e.g. a bus, surge arrester or DC-valve.
  • FIG. 1 showing a schematic cross sectional view of a bushing 1 mounted in a wall 18, such as the tank wall in the case of a transformer.
  • a high voltage conductor 10 runs through the center of a hollow bushing insulator 12 that forms a housing around the high voltage conductor.
  • a condenser core 14 is provided inside the insulator housing for voltage grading of voltage stress that is built up around the high voltage conductor 10.
  • a flange 16 is provided on the outside of the housing 12, by means of which the housing of the bushing is connected to ground, via the transformer tank wall 18.
  • Fig. 1 is also shown how the bottom end portion of the high voltage conductor 10 forms a bottom contact 20 that is arranged to be connected to the internal components of the transformer.
  • a mating internal contact 22 is provided inside the transformer.
  • An upper outer terminal 24 for the conductor 10 is provided at the upper end of the bushing, opposite the bottom contact 20 end. The outer terminal 24 is electrically connected to the conductor 10 through an interface, also forming a top cover of the bushing, in order to electrically connect the conductor and thus the transformer to an external source or device.
  • high voltage is conventionally used for voltages above approximately 50 kV.
  • the upper limit in commercial high voltage devices is generally 1100 kV, but higher voltages, such as 1200 kV or even more, are envisaged in the near future.
  • current levels are increasing and may be up to 4000-5000 A or even higher.
  • the demands on the bushings are naturally increased, e.g. when it comes to heat dissipation and cooling, electric fields, electric insulation of the bushing etc. In this context, it becomes essential to have a low loss and efficient cooling, in particular to be able to reach the target current.
  • the losses in today's bushings mainly occur due to losses in the conductor and in each contact or joint in the current path between different parts of the bushing.
  • the losses in the conductor itself can be optimized by selecting the material, the shape and the size of the conductor.
  • the current is forced to flow from the conductor 10 to the top cover of the bushing via a contact area through the top cover itself, and then via another contact on the outside of the top cover to the outer terminal 24 and external connection. It is recognized that fewer joints would reduce losses which is advantageous in high voltage and high current applications.
  • a high voltage bushing comprising a hollow insulator housing, a high voltage conductor provided inside the housing, a first connection arrangement where the conductor can be connected to a first electric device and a second connection arrangement where the conductor can be connected to a second electric device, characterized in that at least one of said first connection arrangement and said second connection arrangement is designed as an external connection arrangement in which the conductor has an extended end part,and the bushing comprises an exit opening through which the extended end part of the conductor exits from the bushing, in order for the extended end part of the conductor to be connectable to an electric device, and the bushing further comprises a cooling arrangement for cooling of the bushing.
  • An advantage of this invention is that the losses are reduced since the contact surfaces and joints are reduced.
  • at least one of the contact areas of the prior art external terminal is made redundant since the current does not have to flow through the top cover, but can flow directly from the conductor to a contact mounted on the conductor, outside the housing. Reduced losses will reduce the need for cooling of the bushing.
  • Another advantage is that the cooling of the conductor is improved by direct heat transfer to the surrounding air, which is made possible when the conductor extends outside the bushing. Improved cooling will make it possible to transfer higher power through the bushing, i.e., increase voltage and/or current.
  • a further advantage is increased robustness for high currents since fewer parts need to have a current contact function.
  • the cooling arrangement may comprise a heat sink thermally connected to the extended end part of the conductor, by means of which heat sink heat is conducted away from the bushing and thereby achieving cooling.
  • the heat from losses inside the bushing is transferred to the conductor and then to the heat sink and thus can be conducted away.
  • the heat sink may be in direct thermal contact with the extended end part.
  • the heat sink may be thermally connected to a device holding the conductor at the exit opening.
  • the heat sink may be thermally connected to the housing of the bushing.
  • the heat sink comprises a body made of a material with high thermal conductivity.
  • the heat sink may be provided with cooling fins.
  • the heat sink is thermally connected to a corona shield body arranged on the bushing.
  • the cooling arrangement may comprise a heatpipe connecting the heat sink with the corona shield body.
  • the heat sink comprises a corona shield body arranged radially outside the extended end part of the conductor. If there is already a corona shield body on the bushing, it is very practical to use this as a heat sink.
  • the heat sink comprises a hollow body made of a lightweight material.
  • the shape and size of such a body will be adapted to the conditions in every particular case.
  • the heat in the heat sink may be transferred to ambient air by natural convection.
  • the heat in the heat sink is transferred to ambient air by forced convection.
  • the cooling arrangement may comprise a fan arranged to provide forced convection.
  • the heat in the heat sink is removed by a cooling fluid.
  • the heat sink may comprise at least one channel in which a cooling fluid is circulated and the channel may be provided with a connecting device for connecting the channel to an external cooling system.
  • the corona shield body can be a ring-shaped pipe inside which a cooling fluid is circulated.
  • the bushing includes a cover forming part of the housing, that the exit opening for the conductor is designed as a hole in the cover through which hole the extended end part of the conductor exits from the bushing.
  • the cover may be designed as a separate part, or as an integrated part of the housing.
  • the inventive high voltage bushing finds its applicability primarily as a DC bushing. However, it may also be an AC bushing.
  • the inventive high voltage bushing may be a gas insulated bushing.
  • the external connection arrangement of the inventive bushing may be an external air contact, i.e. the inventive details of the bushing are applied to a contact of the bushing, which contact is located at an end of the bushing that is in contact with the surrounding air, for example corresponding to the outer terminal of prior art in Fig. 1 .
  • the bushing may also be a bushing where the housing is a sealed housing whereby the interior of the bushing is sealed off from the surroundings of the bushing. This is required when there is an insulation medium inside the bushing that must not leak out into the surroundings.
  • a high voltage device comprising a bushing in accordance with any one of the claims defining a bushing, and said high voltage device being either one of the first electric device or the second electric device to which the conductor can be connected.
  • high voltage will be used for voltages of 50 kV and higher.
  • the present upper limit for commercial high voltage is 1100 kV, but it is foreseen that the invention can be used also for higher voltages, up to 1200 kV or even more.
  • the present invention will find its applicability from about 200 kV and upwards.
  • FIG. 2a An embodiment of a bushing according to the present invention is schematically illustrated in Fig. 2a .
  • the bushing of this embodiment has the same main parts as the prior art bushing in Fig. 1 , with the exception of the upper part with the outer terminal 24, and the fact that the present invention is not limited to a bushing with a condenser 14.
  • the same reference numerals are used for the same or corresponding parts in the different figures, whenever applicable.
  • the inventive bushing in Fig. 2a comprises a hollow bushing insulator that forms a housing 12.
  • a high voltage conductor 10 runs through the center of the housing.
  • the wall 18 may be a wall of any type of high voltage electric device where high voltage bushings are used. For example, when the electric device is a transformer, the wall 18 would be the transformer tank wall.
  • first connection arrangement 30 in the form of a contact for connecting the conductor with a corresponding contact 22 of an electric device located on this side of the bushing.
  • the electric device on this first side of the bushing will be referred to as a first electric device.
  • the first connection arrangement 30 in the form of the contact would be inside the transformer and the transformer would have a mating internal contact 22.
  • second connection arrangement 32 in the form of an external connection arrangement comprising an exit opening 34 in the housing 12, through which the conductor 10 exits from the bushing.
  • the exit opening is provided with a top cover 35 which has a hole 36 through which the conductor 10 runs to the outside of the bushing.
  • This will in the following be referred to as the second side of the bushing.
  • the conductor 10 may be described as being extended outside the housing of the bushing by means of the conductor having an extended end part 38 forming an extended free end of the conductor.
  • the conductor end part 38 extending outside the bushing is adapted for contact with a second electric device.
  • the second side of the bushing could for instance be connected to an external device, bus or cable.
  • Fig. 2b is illustrated a variant of the embodiment in Fig. 2a and the same reference numerals are used.
  • the variant in Fig. 2b differs from the embodiment in Fig. 2a in that the wall of the housing 12 stretches beyond the extended free end part 38 of the conductor 10.
  • Another way of describing the variant in Fig. 2b is that the cover 35 with the protruding extended end part 38 of the conductor is arranged as being recessed in the upper end of the housing 12 of the bushing.
  • Fig. 3 is illustrated the upper part of a bushing according to the present invention, which bushing comprises a first embodiment of a cooling arrangement.
  • the bushing itself is based on the bushing illustrated in Fig. 2a .
  • the same reference numerals have been used for features having correspondence in the embodiment of Figs. 2a and 2b , and these features will not be repeated here.
  • the conductor 10 of the bushing has an extended end part 38 that extends outside the bushing. Around the extended end part is arranged a heat sink 40.
  • the heat sink is thermally connected to the end part 38 of the conductor, for example by being directly connected to the end part, or by being connected to some kind of holding or clamping device that holds the conductor in the correct position at the exit opening 34.
  • the heat sink may be in thermal contact with the housing 12, in most cases via the cover 35 if there is a separate cover. Combinations of the described alternatives for achieving thermal contact between the conductor and the heat sink are of course also possible.
  • the heat sink 40 is made of a material displaying high thermal conductivity, such as a suitable metal, e.g. copper, aluminum.
  • the heat sink may be solid, or provided with cooling channels as will be described further down.
  • the heat sink may have any shape that is found suitable under the practical circumstances, and its size/mass may be adjusted to the specific needs from case to case.
  • the surface of the heat sink may be provided with cooling fins (not shown).
  • the heat from losses inside the bushing is transferred to the heat sink 40 via the conductor 10 and can be conducted away from the heat sink either by natural convection to surrounding air or gas, or by forced cooling through convection, which may be achieved by the cooling arrangement comprising a fan arranged to blow air or gas onto the heat sink.
  • Other alternatives may include surrounding the heat sink with some other kind of cooling medium.
  • the bushing comprises a second embodiment of an arrangement for cooling.
  • the heat sink of Fig. 3 is combined with a corona shield body 42 arranged radially outside the extended end part 38 of the conductor 10.
  • the corona shield may be a hollow or solid body, e.g. ring-shaped, of metal or some other electrically conductive material.
  • the corona shield is thermally connected to the housing 12 of the bushing 1 and thereby to the conductor 10. In most cases, the corona shield body would be connected to the cover 35 of the housing by a support device 52 comprising plates, bars or similar.
  • a corona shield body is often quite voluminous and therefore offers a substantial surface for heat transfer to the surroundings.
  • natural convection, forced convection etc. may be used.
  • additional equipment for promoting heat transfer between the heat sink and the corona shield body for example such as heatpipes 44 arranged between the heat sink 40 and the corona shield body 42.
  • the bushing comprises a third embodiment of an arrangement for cooling.
  • This arrangement for cooling comprises a corona shield body 50 by itself and it is arranged radially outside the extended end part 38 of the conductor 10.
  • the corona shield may be a hollow or solid ring of metal or some other electrically conductive material. Here it is illustrated as a hollow pipe, for example of a light material such as aluminium.
  • the corona shield is thermally connected to the housing 12 of the bushing 1 via a support device 52 connected to the cover 35 and thereby to the conductor 10.
  • the interior of the pipe may be used for circulating a cooling medium, such as a gas, air, or a liquid, such as water or oil.
  • a cooling medium such as a gas, air, or a liquid, such as water or oil.
  • a liquid such as water or oil.
  • a lightweight body of a thermally conductive material which does not have the function of a corona shield, but merely has the function of enhancing cooling.
  • Such a body may have any conceivable shape that is suitable under the circumstances and it may well be hollow in order to offer the possibility of circulating a cooling fluid, e.g. air.
  • Fig. 6 a fourth embodiment of a cooling arrangement, in which a heat sink 60 similar to Fig. 3 , is illustrated.
  • a heat sink 60 similar to Fig. 3
  • this heat sink 60 is provided a channel 62 in which a cooling fluid may be circulated.
  • the channel is connected to an external cooling system (not illustrated) via connecting means.
  • This channel may also be divided into several channels, in order to achieve good circulation of the cooling fluid from the cooling system.
  • the cooling fluid may be liquid or gas, for example air, water or oil.
  • the housing 12 is shown as comprising a separate cover 35 at its upper end.
  • This cover is provided with an exit opening 34, through which the end part 38 of the conductor 10 exits from the bushing.
  • the cover can be integrated in the housing and be made in one piece with the housing.
  • the conductor extends through the cover, or corresponding integrated part of the housing, heat can be transferred from the conductor to the cover, to the housing, to the corona shield and to the surrounding air. Also electrical contact is ensured between the conductor, the cover, the housing and the corona shield.
  • the bushing is only provided with one external connection arrangement in accordance with the present invention, namely the second connection arrangement 32 at the upper end.
  • the first connection arrangement 30 is illustrated as a regular contact used in prior art. However, it should be perfectly clear that also the first connection arrangement 30 may be designed in the same way as the illustrated second connection arrangement 32, whenever suitable. This may for example be the case when the bushing is a wall bushing between valve halls.
  • the described bushing may be used both for DC and AC applications.
  • a transformer may be a high voltage device on which the inventive high voltage bushing is used.
  • inventive high voltage bushing may also be used with other types of high voltage devices, such as reactors, breakers, generators, switchgear or any other suitable device finding an application in high voltage systems.
  • electric device and high voltage device should also be interpreted as including cables, buses, surge arresters, DC valves and the like, within the context of the present invention.
  • the inventive bushing When the inventive bushing is used in a transformer, oil is used as insulating medium inside the transformer and on the other side of the bushing the medium is air, for example in a HVDC valve hall.
  • This type of bushing is generally referred to as an air-oil bushing.
  • the bushing according to the invention is suitable for use in many electric devices, irrespective of the media on the respective sides of the bushing, such as air-air (wall bushing), air-gas (gas switchgear), etc.
  • the present invention bears no restriction as to the choice of insulation medium inside the bushing. It may for example be gas, oil, gel, or combinations thereof.

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  • Insulators (AREA)
  • Cooling Or The Like Of Electrical Apparatus (AREA)
EP08157484A 2008-06-03 2008-06-03 Traversée haute tension, dispositif haute tension comprenant ladite traversée et procédé de refroidissement Withdrawn EP2131371A1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP08157484A EP2131371A1 (fr) 2008-06-03 2008-06-03 Traversée haute tension, dispositif haute tension comprenant ladite traversée et procédé de refroidissement
CNA2008101264711A CN101599326A (zh) 2008-06-03 2008-07-03 高压套管、包括此套管的高压设备及冷却方法
CN2009201503089U CN201514824U (zh) 2008-06-03 2009-04-29 高压套管及包括此套管的高压设备
DE200920007819 DE202009007819U1 (de) 2008-06-03 2009-06-03 Hochspannungsbuchse und Hochspannungsgerät, das eine solche Buchse umfasst

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP08157484A EP2131371A1 (fr) 2008-06-03 2008-06-03 Traversée haute tension, dispositif haute tension comprenant ladite traversée et procédé de refroidissement

Publications (1)

Publication Number Publication Date
EP2131371A1 true EP2131371A1 (fr) 2009-12-09

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Application Number Title Priority Date Filing Date
EP08157484A Withdrawn EP2131371A1 (fr) 2008-06-03 2008-06-03 Traversée haute tension, dispositif haute tension comprenant ladite traversée et procédé de refroidissement

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Country Link
EP (1) EP2131371A1 (fr)
CN (2) CN101599326A (fr)
DE (1) DE202009007819U1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10630063B2 (en) 2016-05-25 2020-04-21 Siemens Aktiengesellschaft Heat-conducting ceramic bushing for switchgear
RU2819084C2 (ru) * 2021-05-07 2024-05-13 Стейт Грид Корпорейшн Оф Чайна Высоковольтный ввод и высоковольтная система электропередачи

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106486220B (zh) * 2015-09-02 2018-03-23 泰科电子(昆山)有限公司 绝缘套管
CN107967396B (zh) * 2017-12-11 2021-04-02 国网新疆电力有限公司检修公司 高压复合套管在风偏下的电场计算方法
EP3561819B1 (fr) * 2018-04-26 2022-01-26 Hitachi Energy Switzerland AG Bague équipée d'une fibre optique

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3760089A (en) * 1972-04-27 1973-09-18 Westinghouse Electric Corp Electrical bushing assembly having resilient means enclosed within sealing means
US3767835A (en) * 1972-06-07 1973-10-23 Anaconda Co Pothead termination comprising a vapor condenser and a tubular conductor extension containing a vaporizable liquid, and method
DE2757571A1 (de) * 1977-12-23 1979-07-05 Felten & Guilleaume Carlswerk Hochbelastbare stromleiteranordnung, insbesondere fuer hochspannungsdurchfuehrungen
US4358631A (en) * 1980-09-10 1982-11-09 Mitsubishi Denki Kabushiki Kaisha Heat dissipating electrical bushing

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3760089A (en) * 1972-04-27 1973-09-18 Westinghouse Electric Corp Electrical bushing assembly having resilient means enclosed within sealing means
US3767835A (en) * 1972-06-07 1973-10-23 Anaconda Co Pothead termination comprising a vapor condenser and a tubular conductor extension containing a vaporizable liquid, and method
DE2757571A1 (de) * 1977-12-23 1979-07-05 Felten & Guilleaume Carlswerk Hochbelastbare stromleiteranordnung, insbesondere fuer hochspannungsdurchfuehrungen
US4358631A (en) * 1980-09-10 1982-11-09 Mitsubishi Denki Kabushiki Kaisha Heat dissipating electrical bushing

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10630063B2 (en) 2016-05-25 2020-04-21 Siemens Aktiengesellschaft Heat-conducting ceramic bushing for switchgear
RU2819084C2 (ru) * 2021-05-07 2024-05-13 Стейт Грид Корпорейшн Оф Чайна Высоковольтный ввод и высоковольтная система электропередачи

Also Published As

Publication number Publication date
DE202009007819U1 (de) 2009-09-17
CN201514824U (zh) 2010-06-23
CN101599326A (zh) 2009-12-09

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