EP1016101A1 - Enroulement de transformateur ou d'inducteur - Google Patents

Enroulement de transformateur ou d'inducteur

Info

Publication number
EP1016101A1
EP1016101A1 EP98902349A EP98902349A EP1016101A1 EP 1016101 A1 EP1016101 A1 EP 1016101A1 EP 98902349 A EP98902349 A EP 98902349A EP 98902349 A EP98902349 A EP 98902349A EP 1016101 A1 EP1016101 A1 EP 1016101A1
Authority
EP
European Patent Office
Prior art keywords
winding
cable
power transformer
inductor
flexible conductor
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Withdrawn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
EP98902349A
Other languages
German (de)
English (en)
Inventor
Peter Carstensen
Albert Jaksts
Mats Leijon
Li Ming
Rongsheng Liu
Christian Sasse
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 AB
Original Assignee
ABB AB
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
Priority claimed from SE9700335A external-priority patent/SE508556C2/sv
Application filed by ABB AB filed Critical ABB AB
Publication of EP1016101A1 publication Critical patent/EP1016101A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • 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
    • 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
    • H01F29/14—Variable transformers or inductances not covered by group H01F21/00 with variable magnetic bias
    • 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
    • H01F27/288—Shielding
    • 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
    • H01F27/323—Insulation between winding turns, between winding layers
    • 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
    • H01F27/34—Special means for preventing or reducing unwanted electric or magnetic effects, e.g. no-load losses, reactive currents, harmonics, oscillations, leakage fields
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F3/00—Cores, Yokes, or armatures
    • H01F3/10—Composite arrangements of magnetic circuits
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F3/00—Cores, Yokes, or armatures
    • H01F3/10—Composite arrangements of magnetic circuits
    • H01F3/14—Constrictions; Gaps, e.g. air-gaps
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/02—Details
    • H02H3/025—Disconnection after limiting, e.g. when limiting is not sufficient or for facilitating disconnection
    • 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
    • H01F2027/329—Insulation with semiconducting layer, e.g. to reduce corona effect
    • 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
    • H01F29/14—Variable transformers or inductances not covered by group H01F21/00 with variable magnetic bias
    • H01F2029/143—Variable transformers or inductances not covered by group H01F21/00 with variable magnetic bias with control winding for generating magnetic bias
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K2203/00—Specific aspects not provided for in the other groups of this subclass relating to the windings
    • H02K2203/15—Machines characterised by cable windings, e.g. high-voltage cables, ribbon cables

Definitions

  • the present invention relates to power transformers or inductors in a power generation, transmission or distribution system with a rated power ranging from a few hundred kVA up to more than 1000 MVA and with a rated voltage ranging from 3-4 kV and up to very high transmission voltages, 400 kN to 800 kV or higher. More specifically the invention relates to the winding of power transformers or inductors.
  • the space factor of a winding that is the ratio between the volume occupied by the conductor in the winding and the total volume of the winding, is an important parameter. Windings with high space factors are advantageous since they display a compact design and low leakage flux.
  • the objective of the present invention is to provide a power transformer or inductor comprising a flexible conductor having electric field containing means as well as inner electric field equalizing means, which presents a design which is technically favourable and allows a high space factor.
  • the invention is made possible by the use of said flexible conductor in at least a part of the winding or windings in the power transformer /inductor.
  • An example of a flexible conductor having electric field containing means is a flexible XLPE-cable of the sort used for power distribution.
  • Such a cable comprises a conducting core, a first semiconducting layer provided around said conducting core, a solid insulation layer provided around said first semiconducting layer and a second semiconducting layer provided around said insulation layer.
  • the cable On the condition that the second semiconducting layer is grounded the cable has the ability to, within itself, contain the electric field arising from the current in the conducting core. The electric stress is thus absorbed within the solid insulation of the cable and there is virtually no electric field outside the second semiconducting layer.
  • the different layers In a XLPE-cable the different layers are firmly attached to each other.
  • the solid insulation layer and the semiconducting layers are made of materials which have almost the same coefficient of expansion. The cable can therefore be subjected to mechanical and thermal stress without the layers separating from each other, forming cavities in-between the layers. This is an important feature, since partial discharges will appear in a cavity if the electric field stress exceeds the dielectric strength of the gas in the cavity.
  • the voltage in a power transformer or inductor is unevenly distributed over the turns of a winding.
  • the part of the windings connected to ground will have an electric potential close to zero.
  • the part of the winding connected to the line terminal will have a maximum electric potential close to the phase voltage.
  • the line side of the winding is therefore subjected to higher insulation loads than the ground side. To prevent flash-overs between the winding and details close to the winding, e.g. the core or the casing surrounding the power transformer or inductor, a better electric insulation is required on the line side than on the ground side.
  • the required electric insulation thus changes along the length of the winding.
  • star connection Y
  • delta connection ⁇
  • the connections Y or ⁇ can be arbitrarily chosen for the high voltage and the low voltage side of the transformer.
  • Y connection one winding end of each phase is connected together, forming a neutral terminal. If the neutral terminal is grounded, the part of the windings connected to the neutral will have an electric potential close to zero and the part of the windings connected to the line terminals will have a maximum electric potential close to U L / 3 , where U L is the line-to-line voltage.
  • U L is the line-to-line voltage.
  • the windings of all phases together form a closed loop, a delta, and the line terminals are connected to the three corners of the delta. If the system is symmetric, the electric potential in the middle of each winding will be close to zero. On the other hand, the maximum electric potential at the end of each winding will be U L /2. Once again the insulation load changes along the length of the windings and so does the required electric insulation.
  • the cooling will be more efficient since the cooling medium will be able to circulate more easily in the transformer /inductor when the cable insulation is reduced. Since cooling is often the limiting factor in power transformer /inductor design, the capacity rating of a transformer /inductor of a given size can be increased.
  • the thickness of the insulating layer of the cable should be such that the electric stress in the cable, in principal, is the same throughout every turn of the winding.
  • the cross section area may vary continuously or step-wise in one or more steps.
  • a cable with a step-wise varying insulation cross section area may be made of cable parts with different but uniform insulation cross section areas that are joined together.
  • the insulation cross section area may decrease along the length of the cable, the cable then having its smallest insulation cross section in one end of the winding.
  • the cable may alternatively have its smallest insulation cross section area in the middle of the winding, as is suitable for a winding in a ⁇ -connection, or at any other position, all according to how the insulation load changes along the winding.
  • Fig. 1 is a simplified view showing the electric field distribution around a winding of a conventional power transformer or inductor.
  • Fig. 2 is a simplified view showing the electric field distribution around a winding of a power transformer or inductor of the sort described in PCT applications WO-97/45847 and WO-97/45921.
  • Fig. 3 is a simplified view showing the electric field distribution around a winding of a power transformer or inductor according to a first preferred embodiment of the invention.
  • Fig. 4 is a simplified view showing the electric field distribution around a winding of a power transformer or inductor according to a second preferred embodiment of the invention
  • Fig. 5 is a simplified side view showing two examples of step-wise tapered cables and two examples of continuously tapered cables used in windings in a power transformer or inductor according to the invention.
  • the figures 1-3 referred to in the text below are simplified and fundamental views.
  • the figures can represent a inductor, with or without a core, as well as a power transformer. For simplicity reasons, only one winding is shown in each figure. Also for simplicity reasons, windings with only one layer and only four turns are shown in the figures, however, the reasoning below holds for windings with many layers and a multitude of turns.
  • Figure 1 shows a simplified view of the electric field distribution around a winding of a conventional power transformer or inductor with a winding 11 and a core 12.
  • equipotential lines 13 that is, lines where the electric field has constant magnitude.
  • the lower part of the winding is assumed to be at ground potential and the upper part is assumed to be connected to a line terminal.
  • the potential distribution determines the composition of the insulation system since it is necessary to have sufficient insulation both between adjacent turns of the winding and between turns of the winding and grounded details surrounding the winding.
  • the equipotential lines 13 in the figure shows that the upper part of the winding is subjected to the highest insulation loads.
  • FIG. 2 shows a simplified view of the electric field distribution around a winding of a power transformer or inductor described in PCT applications WO- 97/45847 and WO-97/45921.
  • a winding 21 made up by a cable 28 wound round a core 22.
  • equipotential lines 23 are shown.
  • the cable 28 comprises a conducting core 24 surrounded by a first semiconducting layer 25, a solid insulation layer 26 of uniform thickness and a second semiconducting layer 27.
  • the second semiconducting layer 27 is connected to ground potential.
  • the lower part of the winding is assumed to be at ground potential and the upper part is assumed to be connected to a line terminal.
  • the electric field arising from the current in the conducting core is enclosed in the cable 28 by the semiconducting layer 27 and there is no electric field outside the cable 28.
  • the upper part of the winding is subjected to the highest insulation loads and the electric stress absorbed within the insulation layer of the cable in the upper part of the winding is larger than the stress absorbed in the lower part. This is indicated in the figure by the spacing between the equipotential lines 23 in the cable which are smaller in the upper part as compared to the lower part of the winding.
  • the insulation layer in the cable is dimensioned to withstand the highest electrical stress in the winding, that is the stress in the upper part of the winding. This means that the insulating layer in the lower part of the winding is unnecessarily thick.
  • a favourable design of a power transformer or inductor comprising a cable is obtained by adapting the thickness of the insulation of the cable to the actual insulation loads along the winding.
  • the insulation thickness should be such that the electric stress in the cable is, in principal, the same through out the length of the winding.
  • the electric field distribution around a cable in such a winding is shown in figure 3 which shows a simplified view of a first preferred embodiment of the invention.
  • a cable 38 is wound round a core 32 forming a winding 31.
  • equipotential lines 33 are shown.
  • the lower part of the winding is assumed to be at ground potential and the upper part is assumed to be connected to a line terminal.
  • the cross section area of the insulation layer of the cable in the winding changes continuously in such a way that the electric stress in the cable is, in principal, constant throughout the winding, as is indicated by the equipotential lines 33.
  • the cooling will be more efficient since the cooling medium will be able to circulate more easily in the transformer /inductor when the cable insulation is reduced.
  • FIG 4 a simplified view of a power trans former /inductor according to a second preferred embodiment of the invention is shown.
  • a cable 48 is wound round a core 42 forming a winding 41.
  • equipotential lines 43 are shown.
  • the lower part of the winding is assumed to be at ground potential and the upper part is assumed to be connected to a line terminal.
  • the turns of the tapered cable are stacked on top of each other. As compared to the windings in figures 2 and 3, the space factor of the winding is thus increased and the power transformer /inductor can be made smaller and thus cheaper.
  • the cross section area may change step-wise.
  • the cross section area may change step-wise.
  • two or more cable parts with different but uniform insulation cross section areas such a cable may be obtained.
  • Cables 50a and 50b are made of three cable parts, 51a, 52a, 53a and 51b, 52b, 53b respectively.
  • the conducting core 56a respectively 56b, the first semiconducting layer (not shown) and the second semiconducting layer (not shown) of neighbouring cable parts are connected.
  • the cables 50c and 50d are each made of one cable part, the insulation cross section area of which changes continuously along the length of the cable.
  • the insulation cross section area increases along the length of the cable.
  • Such a cable is suitable in a power transformer /inductor where the insulation stress steadily increases along the winding as is the case in, for example, a Y connected three-phase transformer where the neutral is grounded.
  • the insulation cross section area is smallest on the middle.
  • Such a cable is suitable in a ⁇ connected three-phase transformer where the insulation stresses are smallest half way through the windings.
  • the number of cable parts in cables 50a and 50b does not have to be restricted to three.
  • the winding arrangement described above teaches how to apply a tapered cable to a winding in order to bring about a power transformer or inductor according to the invention. It is understood, however, that it is possible to apply tapered cables to single- or polyphase transformers with one or a plurality of windings as well as to inductors, with or without cores, comprising one or a plurality of windings, without deviating from the scope of the invention. It is also understood that it is possible to, within the scope of the invention, apply a tapered cable to a power transformer /inductor where only a part of the winding consists of a cable.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Coils Of Transformers For General Uses (AREA)
  • Coils Or Transformers For Communication (AREA)
  • Insulating Of Coils (AREA)

Abstract

L'invention concerne un transformateur d'alimentation ou un inducteur. L'enroulement (31) du transformateur/inducteur est constitué d'un conducteur souple (38) doté de moyens de rétention d'un champ électrique. Ces moyens permettent de maintenir le champ électrique, dû au courant électrique circulant dans l'enroulement (31), dans la couche isolante du conducteur souple (38). L'épaisseur de la couche isolante du conducteur souple (38) est choisie de sorte que la contrainte électrique (33) soit constante sur toute la longueur de l'enroulement. La section transversale de la couche isolante du conducteur souple (38) est ainsi optimisée, ce qui permet de concevoir un transformateur/inducteur à facteur d'encombrement élevé.
EP98902349A 1997-02-03 1998-02-02 Enroulement de transformateur ou d'inducteur Withdrawn EP1016101A1 (fr)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
SE9700335 1997-02-03
SE9700335A SE508556C2 (sv) 1997-02-03 1997-02-03 Krafttransformator/reaktor
SE9704454 1997-11-28
SE9704454A SE510451C2 (sv) 1997-02-03 1997-11-28 Krafttransformator eller reaktor
PCT/SE1998/000152 WO1998034244A1 (fr) 1997-02-03 1998-02-02 Enroulement de transformateur ou d'inducteur

Publications (1)

Publication Number Publication Date
EP1016101A1 true EP1016101A1 (fr) 2000-07-05

Family

ID=26662861

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98902349A Withdrawn EP1016101A1 (fr) 1997-02-03 1998-02-02 Enroulement de transformateur ou d'inducteur

Country Status (19)

Country Link
EP (1) EP1016101A1 (fr)
JP (1) JP2001509956A (fr)
KR (1) KR20000070659A (fr)
CN (1) CN1246956A (fr)
AP (1) AP1051A (fr)
AU (1) AU726018B2 (fr)
BR (1) BR9807149A (fr)
CA (1) CA2278236A1 (fr)
CU (1) CU22673A3 (fr)
CZ (1) CZ269999A3 (fr)
EA (1) EA001716B1 (fr)
EE (1) EE03457B1 (fr)
IS (1) IS5115A (fr)
NO (1) NO993734L (fr)
NZ (1) NZ336521A (fr)
PL (1) PL334876A1 (fr)
SE (1) SE510451C2 (fr)
UA (1) UA46890C2 (fr)
WO (1) WO1998034244A1 (fr)

Families Citing this family (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE9602079D0 (sv) 1996-05-29 1996-05-29 Asea Brown Boveri Roterande elektriska maskiner med magnetkrets för hög spänning och ett förfarande för tillverkning av densamma
CA2255745A1 (fr) 1996-05-29 1997-12-04 Abb Ab Generateur electrique rotatif comprenant un enroulement de stator haute tension et des dispositifs de support allonges soutenant l'enroulement et procede de fabrication de ce generateur
EE03408B1 (et) 1996-05-29 2001-04-16 Asea Brown Boveri Ab Elektriline kõrgepinge vahelduvvoolumasin
GEP20022779B (en) 1996-05-29 2002-08-26 Abb Ab Power Transformer/ Reactor
SE9704413D0 (sv) 1997-02-03 1997-11-28 Asea Brown Boveri Krafttransformator/reaktor
SE9704412D0 (sv) 1997-02-03 1997-11-28 Asea Brown Boveri Krafttransformator/reaktor
SE510452C2 (sv) 1997-02-03 1999-05-25 Asea Brown Boveri Transformator med spänningsregleringsorgan
SE513083C2 (sv) 1997-09-30 2000-07-03 Abb Ab Synkronkompensatoranläggning jämte användning av dylik samt förfarande för faskompensation i ett högspänt kraftfält
SE513555C2 (sv) 1997-11-27 2000-10-02 Abb Ab Förfarande för applicering av ett rörorgan i ett utrymme i en roterande elektrisk maskin och roterande elektrisk maskin enligt förfarandet
GB2331858A (en) 1997-11-28 1999-06-02 Asea Brown Boveri A wind power plant
GB2331853A (en) 1997-11-28 1999-06-02 Asea Brown Boveri Transformer
DE19854439C2 (de) * 1998-11-25 2000-10-12 Siemens Ag Transformator - insbesondere Giessharztransformator
WO2001052393A1 (fr) † 2000-01-11 2001-07-19 American Superconductor Corporation Machine rotative supraconductrice a supraconducteurs haute temperature
SE516002C2 (sv) 2000-03-01 2001-11-05 Abb Ab Roterande elektrisk maskin samt förfarande för framställning av en statorlindning
US6885273B2 (en) 2000-03-30 2005-04-26 Abb Ab Induction devices with distributed air gaps
SE516442C2 (sv) 2000-04-28 2002-01-15 Abb Ab Stationär induktionsmaskin och kabel därför
DE10120236C1 (de) * 2001-04-19 2003-01-30 Siemens Ag Elektrische Wicklungsanordnung
SE0500901L (sv) * 2005-04-21 2006-04-04 Swedish Neutral Ab En induktiv anordning
JP4885907B2 (ja) * 2008-05-26 2012-02-29 昭和電線デバイステクノロジー株式会社 リッツ線コイル
CN104753220B (zh) * 2015-04-09 2017-03-01 哈尔滨电气动力装备有限公司 10kV电机导线绝缘工艺方法
CN108511163A (zh) * 2018-03-26 2018-09-07 江苏亚威变压器有限公司 一种高频变压器及其树脂浇注方法

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5036165A (en) * 1984-08-23 1991-07-30 General Electric Co. Semi-conducting layer for insulated electrical conductors
JPH0424909A (ja) * 1990-05-15 1992-01-28 Mitsubishi Electric Corp 電磁誘導機器

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9834244A1 *

Also Published As

Publication number Publication date
EA001716B1 (ru) 2001-08-27
JP2001509956A (ja) 2001-07-24
KR20000070659A (ko) 2000-11-25
PL334876A1 (en) 2000-03-27
CZ269999A3 (cs) 1999-11-17
AP9901608A0 (en) 1999-09-30
EA199900713A1 (ru) 2000-02-28
NZ336521A (en) 2000-12-22
NO993734D0 (no) 1999-08-02
EE03457B1 (et) 2001-06-15
NO993734L (no) 1999-10-01
AU726018B2 (en) 2000-10-26
SE9704454L (sv) 1998-08-04
EE9900287A (et) 2000-02-15
SE9704454D0 (sv) 1997-11-28
IS5115A (is) 1999-07-13
CU22673A3 (es) 2001-06-01
AU5890398A (en) 1998-08-25
AP1051A (en) 2002-03-18
CN1246956A (zh) 2000-03-08
UA46890C2 (uk) 2002-06-17
WO1998034244A1 (fr) 1998-08-06
BR9807149A (pt) 2000-01-25
CA2278236A1 (fr) 1998-08-06
SE510451C2 (sv) 1999-05-25

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