CN1165057C - Capacitively controlled high-voltage winding - Google Patents
Capacitively controlled high-voltage winding Download PDFInfo
- Publication number
- CN1165057C CN1165057C CNB008086532A CN00808653A CN1165057C CN 1165057 C CN1165057 C CN 1165057C CN B008086532 A CNB008086532 A CN B008086532A CN 00808653 A CN00808653 A CN 00808653A CN 1165057 C CN1165057 C CN 1165057C
- Authority
- CN
- China
- Prior art keywords
- pilot
- high pressure
- pressure winding
- main traverse
- traverse line
- 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.)
- Expired - Fee Related
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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
- H01F27/34—Special means for preventing or reducing unwanted electric or magnetic effects, e.g. no-load losses, reactive currents, harmonics, oscillations, leakage fields
- H01F27/343—Preventing or reducing surge voltages; oscillations
- H01F27/345—Preventing or reducing surge voltages; oscillations using auxiliary conductors
-
- 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
- H01F27/2871—Pancake coils
Abstract
High-voltage windings of transformers are strengthened, in particular, in their input area by a capacitive control, in order to withstand any surge voltages that are produced. For this purpose, control lines(10)are wound into the high-voltage winding(1), in parallel to an outside wire(5). According to the invention, in order to improve the capacitive control and to increase the capacity, a control line(10)is located spatially inside an outside wire(5). The control line(10), however, is galvanically separated from the outside wire(5).
Description
For rated voltage for example 〉=220kV and unit power for example 〉=the so-called limit power transformer of 200MVA, the coil windings that adopts twisted wire coil windings (Drilleiterspulenwicklungen) to replace being made by the flat wire rod of a large amount of parallel connections is more favourable.Thus, reduce the supplementary loss that causes by controlling magnetic field on the one hand, utilize operational coil bore better by higher volumetric efficiency on the other hand.
The impulse withstand voltage intensity of the Transformer Winding of rated voltage 〉=220kV realizes usually thus, promptly, winding is only made by the coil of mutual winding, perhaps in having the winding input area of the vertical electric capacity of classification, reduce surge voltage, remaining winding can be made by general twin coil circuit, the twin coil circuit for example made by twisted wire.
The manufacturing of winding around all needs soldering to connect in all cases mutually.But adopting under the situation of twisted wire, realize that soldering connects and have great difficulty or can not realize at all.Therefore, in order to avoid soldering under the situation that adopts twisted wire, people are devoted to a kind of twin coil circuit that can twine continuously always.In this twin coil circuit, realize electric capacity control by a special pilot, the soldering of pilot connects can be easy and realize economically.
The present invention relates to a kind of high pressure winding of electric capacity control, it is made by the slab coil that is used for high-power transformer, and this slab coil has the main traverse line and the pilot that spatially is parallel to main traverse line that are used to carry load current that are made of twisted wire.
The high pressure winding of this electric capacity control is open by Germany Patent document DE-OS 24 18230.Wherein, the high pressure winding has a plurality of mutual vertically stacked slab coils, and these slab coils are entwined by a main traverse line that is designed to twisted wire continuously.Article one, pilot spatially is parallel to main traverse line, and it is wrapped on the section of winding of four slab coils continuously at least.This pilot splits at the middle part of this section of winding, and its top and terminal are electrically connected mutually in that winding is outside.This connection forms by soldering and does not have any problem in practice, because the pilot of being made by solid conductor can be realized soldering without difficulty.
By German laid-open document 1 297 217 known another winding construction, this winding includes the pilot that is used for a solid main traverse line of electric capacity ground control.This winding is made up of the twin coil of continuous winding, and in order to realize vertical electric capacity of classification in twin coil, pilot is made into different length.The main traverse line of twin coil by two in parallel be electrically connected and spatially be parallel to each other and thus the solid conductor of electrically insulated from one another constitute, the pilot that is designed to metallic film is wrapped between these two leads.
Not only in German laid-open document 1 297 217 described winding constructions, and in the described winding construction of another piece open source literature DT 24 18 230 A1, vertically electric capacity is also all relevant with winding density with the surge voltage distribution in the winding.But winding density changes along with the crudy that can reach in the mode of not expected.
By German patent application open source literature DE-OS 19 43 724 known a kind of twisted wires that are used for transformer coil, this lead is made up of the flat intraphase conductor of many parallel connections and mutually insulated.Look on the cross section of twisted wire, the position of intraphase conductor periodically exchanges by bending along twisted wire, and this makes every intraphase conductor periodically occupy each possible position in the twisted wire cross section on the whole length of twisted wire.
By German patent DE-PS 23 23 304 known a kind of tap windings that are used for transformer, this winding has a plurality of sub-windings that are electrically connected in series.Each sub-winding is made of a solid conductor respectively, and each solid conductor is respectively arranged with a spatially parallel with it pilot.These pilots and each solid conductor electrically insulated from one another.
Have the winding that is made of the main traverse line of carrying load current by the known a kind of transformer of German patent DE-PS 39 07 287 C2, this main traverse line is made by a kind of high conductance material usually.At least on the part conductor length of main traverse line, there is a pilot wire of making by resistance material spatially to be parallel to the main traverse line setting.This pilot wire is used for damped oscillation.
By German patent DE-PS 36 29 310 known a kind of big ampere wires that winding connects lead that are used for, be a spatially parallel with it shielded conductor on its next door.This shielded conductor is electrically connected with conductive wire by this so-called " current potential connection ", and the total current in the shielded conductor is equalled zero.Shielded conductor is used to shield the magnetic field that electric current produced by the main traverse line of flowing through, and bears heat load with the structure member of avoiding being placed in the current field because of the vortex current that its induced inside produces.
The object of the present invention is to provide a kind of pilot device that is used for the above-mentioned type high pressure winding, this pilot device has bigger vertical electric capacity and can be easy and make reliably.In addition, when being loaded in the transformer, the high pressure winding also guarantees high operational reliability.
At this, vertically electric capacity can be understood as be between the main traverse line that constitutes winding and pilot with long measure relevant electric capacity.
Above-mentioned purpose realizes like this that in the high pressure winding of the described type of this paper preface promptly according to the present invention, pilot spatially is arranged on main traverse line inside, but this pilot cuts off with main traverse line on electric current.
Because pilot is positioned at the main traverse line inside that is made of twisted wire, so it is spatially very near all intraphase conductors.These intraphase conductors constitute a twisted wire usually, obtain a big vertical electric capacity thus.In addition, vertical electric capacity of this high pressure winding is irrelevant with the axial cooling duct that may exist.Can especially easily make the high pressure winding with this main traverse line, because can twine main traverse line and pilot simultaneously.In addition, by pilot being arranged on main traverse line inside, that is shield pilot, can obtain very high operational reliability by main traverse line.The maximum voltage load that pilot between two axial adjacent windings can bear always only equals to be applied to the twice of the voltage on the slab coil based on this shielding.
According to the suitable expansion structure of the present invention one, pilot is arranged on spatially that two heaps are flat mutually to be stacked, constitute jointly between the solid conductor of main traverse line, and is erected between this two heaps solid conductor.The pilot of She Zhiing abuts on the corresponding side of two heap solid conductors like this.This side is compared very smooth with the outer surface of twisted wire, this makes to have only very little spacing and obtain a very big vertical electric capacity thus between side and pilot.
According to structure with advantage of the present invention, pilot constitutes a length-width ratio on cross section be 15: 1 rectangle, and the entire cross section of sealing the main traverse line of pilot approximately is square.
Pilot preferably by be parallel to each other on many radical spaces, each other the solid conductor of electric insulation constitutes.In pilot, produce small eddy current loss thus.
Improve structure according to of the present invention another, pilot extends on the part of slab coil, and is filled with the filler of being made by insulating material in the main traverse line of all the other slab coil parts.
The coil turn that slab coil inside is furnished with pilot preferably reduces along with the increase of distance between slab coil and the high pressure winding joint.Make vertical electric capacity begin to reduce thus, and the potential pulse that produces on the joint is distributed on a plurality of coils in the high pressure winding towards high pressure winding the inside from joint.
Be preferably in intraphase conductor that two heaps in the slab coil of no pilot constitute main traverse line and an intermediate layer be set between piling, its cross section is equivalent to comprise the cross section of the pilot of pilot insulating barrier.
According to another structure of the present invention, draw a lug plate of pilot respectively by an outermost turn circle with slab coil of a pilot, and the lug plate of adjacent slab coil is electrically connected mutually by a pilot wiring respectively, and slab coil radially is positioned at inner leading wire turn circle and connects by a winding wiring.
According to high pressure winding of the present invention is to have very much advantage, and this is significantly greater than the known structure in all fronts because its vertical electric capacity spatially joins with the special closely lotus root of main traverse line based on pilot.Meanwhile, required processing charges is explained apparent the minimizing with respect to known solution.Usually after processing the high pressure winding, the high pressure winding is tightened by anchor clamps that winding applied axial clamping force.If be provided with the pilot that is designed to flat conductor in main traverse line inside and twine main traverse line, make flat conductor be positioned on the sagittal plane, then especially can obtain such advantage, promptly, always constant at pilot and the distance that is centered around between the intraphase conductor of main traverse line of its both sides, clamping force has only very little variation in time.Make vertical electric capacity of high pressure winding almost always constant thus.
Describe embodiments of the invention in detail by accompanying drawing below, in the accompanying drawing:
Fig. 1 is the sectional view of high pressure winding,
Fig. 2 is the amplification diagrammatic sketch at the local A place of high pressure winding shown in Figure 1,
Fig. 3 is the cross-sectional view that is combined with the main traverse line of pilot,
Fig. 4 is the cross-sectional view with main traverse line of filler,
Fig. 5 is the cross-sectional view with the main traverse line in intermediate layer,
Fig. 6 is the cross-sectional view with main traverse line of the pilot that is made of a plurality of solid conductors.
Corresponding components is all represented with identical Reference numeral in institute's drawings attached mutually.
The high pressure winding 1 along axis 18 orientations of high-power transformer (for example rated power greater than 200MVA and rated voltage more than or equal to 220kV) has joint 2 and 3, and wherein, joint 2 constitutes high pressure connections (referring to Fig. 1).
High pressure winding 1 is formed (see figure 2) by a plurality of slab coil 4A to 4L.These slab coils 4A to 4L is entwined by having best main traverse line 5 near square sectional, and wherein, main traverse line 5 is at slab coil 4A, 4C, 4E, 4G twines respectively among 4I and the 4K from outside to inside, and at 4B, 4D, 4F, 4H then outwards twines from the lining respectively among 4J and the 4L.Slab coil 4A to 4L by being positioned at high pressure winding 1 inside winding wiring 6 and be electrically connected in series (referring to Fig. 2) by the winding wiring 7 that is positioned on high pressure winding 1 neighboring.Slab coil 4A to 4L also can be in pairs (4A, 4B); (4C, 4D); (4E, 4F); (4G, 4H); (4I, 4J) and (4K combines with the twin coil form 4L), and wherein each twin coil can be entwined by a main traverse line respectively.
Main traverse line 5 (referring to Fig. 3 to 5) is made up of two heaps 16 and 17 intraphase conductors that are parallel to each other 8, and every heap intraphase conductor is made up of a plurality of intraphase conductors 8 that recline mutually with its wide side, although the insulation electrical connection all in parallel each other of these intraphase conductors 8.Along main traverse line 5, alternately an intraphase conductor 8 is guided to another intraphase conductor heap 17 from intraphase conductor heap 16 by the intersection 9 that only illustrates, guide to intraphase conductor heap 16 again from this another intraphase conductor heap 17.Thisly alternately periodically carry out along main traverse line 5, this makes the every intraphase conductor 8 in main traverse line 5 length sections occupy each possible intraphase conductor position.Form a so-called twisted wire thus, this is also referred to as in electric generator structure reins in shellfish conductor (Roebelstab).
Between the lead heap 16 and 17 that constitutes by a plurality of solid conductors 8, exist the spacing of solid conductor 8 thickness orders of magnitude.This spacing according to Fig. 3 by one the insulation pilot 10 fillings, according to Fig. 4 by filler 11 fillings according to Fig. 5 by an intermediate layer 12 fillings.Pilot 10 has the cross section near rectangle, and wherein the length-width ratio of rectangle is 15: 1.The solid conductor that pilot 10 can be designed to insulate, especially flat conductor, solid conductor 15 perhaps radially stacked mutually by many as main traverse line 5, mutually insulated is made (referring to Fig. 6).Each solid conductor 15 in parallel electrical connection.Filler 11 is made by insulating material, and it has the cross section the same with pilot 10 and equally has identical insulating covering with pilot.Intermediate layer 12 has the cross section identical with the cross section of the pilot that comprises insulating covering.
The pilot 10, filler 11 and the intermediate layer 12 that have insulating covering are erected between the two heap solid conductors 8.Make solid conductor 8 spatially especially with respect to pilot 10 close arrangement thus.
On the one hand be solid conductor 8 in parallel and that spatially closely recline mutually and be pilot 10 on the other hand, because their very little each other spatial separation constitute the capacitor with relatively large electric capacity.
In illustrated embodiment (referring to Fig. 2), every pilot 10A in the first and second slab coil 4A or 4B or all 5 circle circles of 10B extend past, every pilot 10C among the third and fourth slab coil 4C or the 4D or 10D extend past 3 circle coils, every pilot 10E among the 5th and the 6th slab coil 4E or the 4F or 10F extend past 2 circle coils, and every pilot 10G to 10J extend past 1 circle coil among the 7th to the tenth slab coil 4G to 4J.In remaining slab coil 4K of high pressure winding 1 and 4L, do not have pilot, only be filled with intermediate layer 12.That do not have to replace pilot in the circle circle of pilot in slab coil 4A to 4J is filler 11C to 11J.
Pilot 10A-10J draws and is used to from their slab coil 4A-4J separately by a lug plate 13A-13J who is not shown specifically respectively and electrically contacts.
By winding wiring 6 direct interconnective slab coil 4A to 4J, be slab coil (4A, 4B); (4C, 4D); (4E, 4F); (4G is 4H) with (4I, lug plate 13A to 13J 4J) is electrically connected by a pilot wiring 14A to 14E respectively mutually in high pressure winding 1 outside.Pilot 10A and 10B and 10C and 10D and 10E and 10F and 10G and 10H and 10I and 10J are electrically connected in series.
As mentioned above, pilot 10A to 10J extends through the different circle number of turns, thus the also corresponding difference of vertical electric capacity of slab coil 4A to 4J.Wherein, vertical electric capacity maximum of slab coil 4A and 4B, and vertical electric capacity minimum of slab coil 4I to 4J.In other words, reduce along with the main traverse line 5 that enters high pressure winding 1 from the vertical electric capacity of joint 2 beginnings.Thus, the potential pulse that is applied to the special high frequency on the joint 2 is directed in the high pressure winding like this, makes voltage drop be distributed on many circle circles.(frequency that at first depends on potential pulse) in the ideal case by the vertical electric capacity that reduces, forces approximate being evenly distributed on the high pressure winding 1 of potential pulse of an impact type.
Look different precondition, promptly the characteristic and the structure of the coil turn of each slab coil 4A to 4L and an electrical network that is connected with the high pressure winding also can advantageously be carried out other classification.
Be positioned at high pressure winding shown in Figure 11 local A below the slab coil 4A-4L that is not shown specifically can by one be designed to twisted wire, do not have pilot and do not have filler or the main traverse line in intermediate layer constitutes.
Claims (9)
1. the high pressure winding of an electric capacity control that is used for big specified power transformer, it is made by a plurality of slab coils (4), this slab coil (4) has the main traverse line that is used for load current (5) that is made of twisted wire, and on electric current, cut off and spatially parallel with it pilot (10) with main traverse line, wherein, described main traverse line is by two heaps (16,17) intraphase conductor (8) of next-door neighbour's setting constitutes mutually, intraphase conductor in each heap is flat stacking mutually, and described pilot (10) is made of flat conductor, and spatially be arranged on two inner heaps (16 of main traverse line (5), 17) between the intraphase conductor (8), it is characterized in that described pilot (10) is erected between two heaps (16, the 17) intraphase conductors (8) of main traverse line (5).
2. high pressure winding as claimed in claim 1 is characterized in that, described pilot (10) constitutes a length-width ratio on cross section be 15: 1 rectangle.
3. high pressure winding as claimed in claim 1 or 2 is characterized in that, described pilot (10) spatially is arranged parallel to each other by many and the solid conductor (15) of mutual electric insulation constitutes.
4. high pressure winding as claimed in claim 1 or 2 is characterized in that, the entire cross section that has the main traverse line (5) of the pilot (10) in being encapsulated in is square.
5. high pressure winding as claimed in claim 1 or 2, it is characterized in that, the part of described pilot (10A) extend past slab coil (4A), and in the main traverse line (5) of all the other slab coils (4A) part, have the filler of making by insulating material (11).
6. high pressure winding as claimed in claim 5 is characterized in that, each slab coil (4A-4J) inside is furnished with the coil turn of pilot (10A-10J) along with each slab coil (4A-4J) reduces with the increase of high pressure winding (1) joint (2) distance.
7. high pressure winding as claimed in claim 1 or 2, it is characterized in that, there be not the slab coil (4K of pilot, 4L), two heaps (16,17) be provided with an intermediate layer (12) between the intraphase conductor (8) of formation main traverse line (5), its cross section is equivalent to comprise the cross section of the pilot (10) of insulating covering.
8. high pressure winding as claimed in claim 1 or 2 is characterized in that, is drawn the lug plate (13A) of pilot (10A) by the outmost circle circle of the slab coil with pilot (10A) (4A).
9. high pressure winding as claimed in claim 8, it is characterized in that, adjacent slab coil (4A, lug plate (13A 4B), 13B) mutually be electrically connected, and adjacent slab coil radially is positioned at inner leading wire turn circle and connects by single line circle wiring (6) by a pilot wiring (14A).
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19926540.2 | 1999-06-10 | ||
| DE19926540A DE19926540C1 (en) | 1999-06-10 | 1999-06-10 | Capacitatively controlled high voltage winding |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1354883A CN1354883A (en) | 2002-06-19 |
| CN1165057C true CN1165057C (en) | 2004-09-01 |
Family
ID=7910840
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB008086532A Expired - Fee Related CN1165057C (en) | 1999-06-10 | 2000-06-09 | Capacitively controlled high-voltage winding |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP1183696B1 (en) |
| CN (1) | CN1165057C (en) |
| AT (1) | ATE350756T1 (en) |
| BR (1) | BR0011458B1 (en) |
| DE (2) | DE19926540C1 (en) |
| PT (1) | PT1183696E (en) |
| WO (1) | WO2000077800A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102004013416A1 (en) * | 2004-03-18 | 2005-10-06 | Nexans | Main conductor for a capacitively controlled high voltage winding |
| EP2045898A1 (en) * | 2007-10-04 | 2009-04-08 | Essex Europe SAS | Electric CTC |
| CN106205839A (en) * | 2016-08-31 | 2016-12-07 | 株洲市科达电机技术有限公司 | High frequency lead and preparation method thereof |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1001512A (en) * | 1960-11-24 | 1965-08-18 | English Electric Co Ltd | Improvements in or relating to electric transformers |
| GB1158325A (en) * | 1965-11-09 | 1969-07-16 | English Electric Co Ltd | Improvements in or relating to Windings for Inductive Apparatus. |
| DE1943724A1 (en) * | 1969-01-20 | 1970-07-30 | Transform Roentgen Matern Veb | Drill ladder |
| DE2323304C3 (en) * | 1973-05-09 | 1978-09-07 | Transformatoren Union Ag, 7000 Stuttgart | Step winding for transformers |
| DE2418230C3 (en) * | 1974-04-13 | 1979-09-13 | Transformatoren Union Ag, 7000 Stuttgart | Capacitively controlled high-voltage winding made of disc coils for transformers with high outputs |
| US4489298A (en) * | 1982-03-04 | 1984-12-18 | Westinghouse Electric Corp. | Insulating structure for magnetic coils |
| DE3629310A1 (en) * | 1986-08-28 | 1988-03-10 | Transformatoren Union Ag | High-current conductor for special transformers |
| DE3907287A1 (en) * | 1989-03-07 | 1990-09-13 | Siemens Ag | Transformer having windings composed of main conductors and additional conductors |
| BR9107321A (en) * | 1991-09-26 | 1995-10-17 | Siemens Ag | Process for the manufacture of a coil winding arrangement |
-
1999
- 1999-06-10 DE DE19926540A patent/DE19926540C1/en not_active Expired - Fee Related
-
2000
- 2000-06-09 BR BRPI0011458-8A patent/BR0011458B1/en not_active IP Right Cessation
- 2000-06-09 CN CNB008086532A patent/CN1165057C/en not_active Expired - Fee Related
- 2000-06-09 AT AT00949084T patent/ATE350756T1/en active
- 2000-06-09 PT PT00949084T patent/PT1183696E/en unknown
- 2000-06-09 EP EP00949084A patent/EP1183696B1/en not_active Expired - Lifetime
- 2000-06-09 WO PCT/DE2000/001920 patent/WO2000077800A1/en active IP Right Grant
- 2000-06-09 DE DE50013938T patent/DE50013938D1/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| BR0011458B1 (en) | 2014-12-16 |
| EP1183696B1 (en) | 2007-01-03 |
| EP1183696A1 (en) | 2002-03-06 |
| ATE350756T1 (en) | 2007-01-15 |
| BR0011458A (en) | 2002-03-19 |
| WO2000077800A1 (en) | 2000-12-21 |
| DE50013938D1 (en) | 2007-02-15 |
| PT1183696E (en) | 2007-02-28 |
| CN1354883A (en) | 2002-06-19 |
| DE19926540C1 (en) | 2001-01-11 |
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| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C06 | Publication | ||
| PB01 | Publication | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20040901 Termination date: 20180609 |
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| CF01 | Termination of patent right due to non-payment of annual fee |