CN107084803B - Transformer winding major insulation temperature gradient tests system under stopping up of oil channel - Google Patents
Transformer winding major insulation temperature gradient tests system under stopping up of oil channel Download PDFInfo
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- CN107084803B CN107084803B CN201710339081.1A CN201710339081A CN107084803B CN 107084803 B CN107084803 B CN 107084803B CN 201710339081 A CN201710339081 A CN 201710339081A CN 107084803 B CN107084803 B CN 107084803B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K13/00—Thermometers specially adapted for specific purposes
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K1/00—Details of thermometers not specially adapted for particular types of thermometer
- G01K1/14—Supports; Fastening devices; Arrangements for mounting thermometers in particular locations
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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
- H01F27/28—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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- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Housings And Mounting Of Transformers (AREA)
Abstract
The invention discloses transformer winding major insulation temperature gradients under a kind of stopping up of oil channel to test system, the load loss of each section of high and low pressure winding of control is simulated using high and low pressure DC power supplier, the phenomenon that using electro-insulating rubber block analogue transformer stopping up of oil channel, the temperature of temperature in use sensor measurement winding major insulation each section.Therefore, the present invention can study the transformer winding major insulation temperature gradient distribution under stopping up of oil channel, help to study winding major insulation heat ageing situation when stopping up of oil channel caused by the failures such as oil stream under Natural Oil Circulation Power is cured, sundries is accumulated in oil and winding insulation expands, to further determine that the insulation quality of transformer at low flow rates.
Description
Technical field
The invention belongs to oil-immersed transformer insulation condition diagnosis fields, and in particular under a kind of stopping up of oil channel transformer around
Group major insulation temperature gradient tests system.
Background technology
Can oil-immersed power transformer work normally the peace to entire power grid as the core equipment in network system
Row for the national games has vital meaning.The service life of transformer often determines by its internal insulating materials service life, absolutely
Edge intensity is high, and functional reliability is just strong.Therefore aging transformer insulated under different operating modes and damage situations are studied, to optimization
The stable operation of design of transformer and power grid has far-reaching realistic meaning.
The oil-immersed transformer to come into operation at this stage mostly uses greatly Natural Oil Circulation Power pattern and radiates, in such case
Oil stream may occur between winding wire cake and layer insulation and stagnate even solidification for lower oil stream speed very little；Work as transformer
Winding has the distribution of uneven loss to also result in the part expansion of windings section because adstante febre is lost；In addition, transformer is being transported
During row, insulating oil inevitably adulterates some magazine mixtures, and the accumulation for a long time of these mixtures will influence interior
The circulation of oil flow in portion.Stopping up of oil channel under several situations can cause in various degree above seriously affects internal oil stream heat dissipation,
Especially near hot spot region, extreme temperatures also seriously increase the extent of the destruction of insulation.
Currently, few researchers, using winding insulation temperature gradient as object, insulation when research oil duct blocks is old
Change situation.Therefore, in order to further investigate when oil duct because various failures block when winding major insulation temperature gradient distribution, really
Determine the insulation ag(e)ing degree of transformer, it is necessary to build a kind of temperature gradient of the transformer winding major insulation under stopping up of oil channel
Test device and system.
Invention content
In view of the above deficiency of the prior art, it can more precisely simulate oil duct the object of the present invention is to provide one kind and block up
The lower transformer winding major insulation temperature gradient of plug tests system, and specific means is：
Transformer winding major insulation temperature gradient tests system under a kind of stopping up of oil channel, exhausted for studying transformer winding master
Edge actual motion load under temperature gradient distribution, mainly by high-voltage winding (1), low pressure winding (2), winding major insulation (3),
High-pressure side DC power supplier (4), low-pressure side DC power supplier (5), flow velocity acquisition module (6), experimental box (7), temperature pass
Sensor (8), temperature collecting module (9), computer (10) and electro-insulating rubber block (12) composition, wherein：
High-voltage winding (1), low pressure winding (2), winding major insulation (3), temperature sensor (8) and the insulation rubber
Blob of viscose (12) is internal in experimental box (7)；High-voltage winding (1), winding major insulation (3) and low pressure winding (2) ecto-entad are in concentric
Cylinder EDS maps；
The high-pressure side DC power supplier (4) is connected with the high-voltage winding (1), the low-pressure side direct current
Source module (5) is connected with the low pressure winding (2)；
The winding major insulation (3) is located at the high-pressure side DC power supplier (4) and the low-pressure side direct current
Between power module (5)；
The temperature sensor (8) is sequentially fixed at winding major insulation outer surface from bottom to top using high-temperature insulating glue
At portion 10%, 50% and 90%；
Electro-insulating rubber block is placed between high-voltage winding (1) and low pressure winding (2), is insulated in the first layer of high-voltage winding (1)
At bottom-up 5% position of cylinder；And along the circumferential direction at mutual position in 90 °
Temperature collecting module (9) is connected with temperature sensor (8), the real time temperature for recording winding layer insulation；
Flow velocity acquisition module (6) acquires the oil stream speed in experimental box (7), and flow control acquisition module is placed in experimental box side
On the oil communication pipeline (13) of wall.
The computer (10) respectively with the temperature collecting module (9) and the flow velocity acquisition module (6)
It is connected, is handled for later data.
Further, the high-voltage winding (1) and low pressure winding (2) are respectively n sections and m sections, and n and m are by corresponding winding
The number of plies divided by 6 decisions round up if it is decimal；The high-voltage winding (1) and low pressure winding (2) is top-down, often
Section is made of 6 layer line cakes (11), if its final stage is just built with actual layer number less than 6 layers；Line cake in every section of winding
(11) it is connected using conducting wire；It is not electrically connected between every section of winding.
Further, the high-pressure side DC power supplier (4) respectively includes n and m with low-pressure side DC power supplier (5)
A DC power supply, n and m are determined by the corresponding winding number of plies divided by 6, if it is decimal, are rounded up；Each DC power supply is only
It is connected with one section of winding, top-down numbering i=1,2 ... n-1, n and j=1,2 ... m-1, m；High-pressure side DC power supply
Output powerPH0For high-voltage winding D.C. resistance total losses；Low-pressure side DC power supply
Output powerPL0For low pressure winding D.C. resistance total losses.
Further, the winding major insulation (3) on the inside of the high-voltage winding (1) to total k layers on the outside of low pressure winding (2),
Major insulation outer surface is followed successively by from mounting temperature sensor (8) at bottom to top 10%, 50% and 90%, installation site number
1,2,3, therefore sensor measured temperature Tab(wherein a numbers for installation site, and b is main insulating layer number, k layers total) is represented by：
Further, the electro-insulating rubber block (12) is located at first layer insulating cylinder (301) from high-voltage winding (1) ing and the
At 5% position of spacing bottom of two layers of insulating cylinder (302), and along the circumferential direction mutually the electro-insulating rubber block at position in 90 ° is successively
It is expressed as M1(1201), M2(1202), M3(1203) and M4(1204)。
By above technical scheme it is found that this application provides transformer winding major insulation temperature gradients under a kind of stopping up of oil channel
Test system, high-pressure side DC power supplier (4) control the loss of every section of high-voltage winding (1), low-pressure side DC power supplier (5)
The loss of every section of high-voltage winding (2) is controlled, temperature sensor (8) measures the real time temperature at the specified place of winding major insulation (3).Cause
This, the output power which can control each DC power supply carrys out the non-homogeneous loss of analogue transformer winding, while
The temperature gradient distribution that winding layer insulation is determined in the case of stopping up of oil channel, further increases winding under Natural Oil Circulation Power low flow velocity
The accuracy of insulating thermal aging monitoring.
Description of the drawings
In order to illustrate more clearly of the technical solution of the application, letter will be made to attached drawing needed in the embodiment below
Singly introduce：
Fig. 1 is that transformer winding major insulation temperature gradient test system simplification is cutd open under a kind of stopping up of oil channel provided by the present application
Face figure；
Fig. 2 is the test device signal of 10kV Winding in Power Transformer major insulation temperature gradient under actual loading loss
Figure；
Fig. 3 is 10kV Winding in Power Transformer major insulation and temperature sensor arrangement schematic diagram；
Fig. 4 is that schematic diagram is arranged in electro-insulating rubber block.
Wherein, 1- high-voltage windings, 2- low pressure windings, 3- winding major insulations, the high-pressure sides 4- DC power supplier, 5- low-pressure sides
DC power supplier, 6- flow velocity acquisition modules, 7- experimental boxs, 8- temperature sensors, 9- temperature collecting modules, 10- computers；
401-H1DC power supply, 402-H2DC power supply, 403-H3DC power supply, 404-H4DC power supply, 405-H5DC power supply, 406-
H6DC power supply, 501-L1DC power supply, 502-L2DC power supply, 503-L3DC power supply, 504-L4DC power supply, 505-L5Directly
Galvanic electricity source；301- first layers insulating cylinder, 302- second layers insulating cylinder, 303- third layer insulating cylinders；801-T11Temperature sensor,
802-T12Temperature sensor, 803-T13Temperature sensor, 804-T21Temperature sensor, 805-T22Temperature sensor, 806-T23
Temperature sensor, 807-T31Temperature sensor, 808-T32Temperature sensor, 809-T33Temperature sensor；1201-M1Insulation rubber
Blob of viscose, 1202-M2Electro-insulating rubber block, 1203-M3Electro-insulating rubber block, 1204-M4Electro-insulating rubber block.
Specific implementation mode
This application provides transformer winding major insulation temperature gradients under a kind of stopping up of oil channel to test system, becomes for studying
Depressor winding major insulation actual motion load under temperature gradient distribution, experimental provision mainly by high-voltage winding (1), low pressure around
Group (2), winding major insulation (3), high-pressure side DC power supplier (4), low-pressure side DC power supplier (5), flow velocity acquisition module
(6), experimental box (7), temperature sensor (8), temperature collecting module (9), computer (10) and electro-insulating rubber block (12) composition；
The high-pressure side DC power supplier (4) is connected with the high-voltage winding (1), the low-pressure side direct current
Source module (5) is connected with the low pressure winding (2)；
The winding major insulation (3) is located at the high-pressure side DC power supplier (4) and the low-pressure side direct current
Between power module (5)；
The temperature sensor (8) is sequentially fixed at winding major insulation outer surface from bottom to top using high-temperature insulating glue
At portion 10%, 50% and 90%；
The electro-insulating rubber block (12) is between the high-voltage winding (1) and the low pressure winding (2) close to high
At bottom-up 5% position of first layer insulating cylinder for pressing winding (1)；
Oil stream speed in flow velocity acquisition module (6) the acquisition experimental box (7)；
The temperature collecting module (9) is connected with the temperature sensor (8), for recording winding layer insulation
Real time temperature；
The computer (10) respectively with the temperature collecting module (9) and the flow velocity acquisition module (6)
It is connected, is handled for later data.
The operation principle of the present invention：The high-voltage winding (1) and low pressure winding (2) are respectively n sections and m sections, n and m by
The corresponding winding number of plies divided by 6 decisions round up if it is decimal；The high-voltage winding (1) and low pressure winding (2)
Top-down, every section is made of 6 layer line cakes (11), if its final stage is just built with actual layer number less than 6 layers；Every section around
Line cake (11) in group is connected using conducting wire；It is not electrically connected between every section of winding；The high-pressure side DC power supplier
(4) n and m DC power supply are respectively included with low-pressure side DC power supplier (5), n and m are determined by the corresponding winding number of plies divided by 6
It is fixed, if it is decimal, round up；Each DC power supply is only connected with one section of winding, top-down numbering i=1, and 2 ...
N-1, n and j=1,2 ... m-1, m；The output power of high-pressure side DC power supplyPH0For height
Press winding D.C. resistance total losses；The output power of low-pressure side DC power supplyPL0It is low
Press winding D.C. resistance total losses.The winding major insulation (3) is from the inside of high-voltage winding (1) to total k on the outside of low pressure winding (2)
Layer, in major insulation outer surface from mounting temperature sensor (8) at bottom to top 10%, 50% and 90%, installation site is numbered
It is followed successively by 1,2,3, therefore sensor measured temperature Tab(wherein a numbers for installation site, and b is main insulating layer number, k layers total) can indicate
For：The electro-insulating rubber block (12) is located at the first layer insulating cylinder from high-voltage winding (1)
(301) and at 5% position of spacing bottom of second layer insulating cylinder (302), and the along the circumferential direction insulation rubber at mutual position in 90 °
Blob of viscose is represented sequentially as M1 (1201), M2 (1202), M3 (1203) and M4 (1204).
Therefore, which can control the output power of each DC power supply and carry out the non-homogeneous damage of analogue transformer winding
Consumption, while determining the temperature gradient distribution of winding layer insulation in stopping up of oil channel.
System above can test system by transformer winding major insulation temperature gradient under a kind of stopping up of oil channel and realize, with
For 10kV power transformers, capacity 630kVA, D.C. resistance loss is 9450W under rated condition, takes a wherein phase,
The loss of low pressure winding D.C. resistance is 1950W, and the loss of high-voltage winding D.C. resistance is 1200W, high-voltage winding line cake (11) number of plies
It is 36, low pressure winding line cake (11) number of plies is 30, and the winding insulation number of plies is 3, and Examination on experimental operation includes the following steps：
1) it calculates
2) conducting wire series connection is used to be used as one section, totally 6 sections every 6 layer line cake (11) of high-voltage winding (1)；By low pressure winding
(2) every 6 layer line cake (11) uses conducting wire series connection to be used as one section, totally 5 sections；
3) 6 high-pressure side DC power supplies are connected with 6 sections of high-voltage windings, are H from pushing up from lower number1(401)、H2(402)、
H3(403)、H4(404)、H5(405)、H6(406)；5 low-pressure side DC power supplies are connected with 5 sections of low pressure windings, from top under
Number is L1(501)、L2(502)、L3(503)、L4(504)、L5(505)；
4) according to formulaThe output power difference of each DC power supply in high-pressure side is set
For PH1=300W, PH2=200W, PH3=200W, PH4=200W, PH5=200W, PH6=300W；According to formulaThe output power that each DC power supply of low-pressure side is arranged is respectively PL1=585W, PL2=
390W、PL3=390W, PL4=390W, PL5=585W；
5) according to expression formula(wherein k=3) obtains the temperature of different insulative cylinder everywhere,
Number is respectively T11(801)、T12(802)、T13(803)、T21(804)、T22(805)、T23(806)、T31(807)、T32(808)、
T33(809)；
6) the spacing bottom 5% of the first layer insulating cylinder (301) and second layer insulating cylinder (302) from high-voltage winding (1)
At position, and along the circumferential direction setting electro-insulating rubber block is followed successively by M at mutual position in 90 °1(1201), M2(1202), M3(1203)
And M4(1204).The height of electro-insulating rubber block is set as 50mm in the present embodiment.
7) each DC power supply is connected, transformer winding is heated；
8) start operation flow velocity acquisition module (6) so that the insulating oil in experimental box (7) keeps certain flow velocity；
9) start-up temperature acquisition module (9) record the real time temperature of winding layer insulation；
10) by computer (10) for later data processing.
By above technical scheme it is found that this application provides transformer winding major insulation temperature gradients under a kind of stopping up of oil channel
Test system, high-pressure side DC power supplier (4) control the loss of every section of high-voltage winding (1), low-pressure side DC power supplier (5)
The loss of every section of high-voltage winding (2) is controlled, temperature sensor (8) measures the real time temperature at the specified place of winding major insulation (3).Cause
This, the output power which can control each DC power supply carrys out the non-homogeneous loss of analogue transformer winding, while
The temperature gradient distribution that winding layer insulation is determined in the case of stopping up of oil channel, further increases winding under Natural Oil Circulation Power low flow velocity
The accuracy of insulating thermal aging monitoring.
Claims (1)
1. transformer winding major insulation temperature gradient tests system under a kind of stopping up of oil channel, for studying transformer winding major insulation
Temperature gradient distribution when Natural Oil Circulation Power issues raw stopping up of oil channel, which is characterized in that mainly by high-voltage winding (1), low pressure
Winding (2), winding major insulation (3), high-pressure side DC power supplier (4), low-pressure side DC power supplier (5), flow velocity acquire mould
Block (6), experimental box (7), temperature sensor (8), temperature collecting module (9), computer (10) and electro-insulating rubber block (12) group
At, wherein：
High-voltage winding (1), low pressure winding (2), winding major insulation (3), temperature sensor (8) and electro-insulating rubber block are arranged in reality
Tryoff (7) is internal；High-voltage winding (1), winding major insulation (3) and low pressure winding (2) ecto-entad are in concentric column EDS maps；
High-pressure side DC power supplier (4) is connected with high-voltage winding (1), low-pressure side DC power supplier (5) and low pressure winding (2)
It is connected；
Winding major insulation (3) is located between high-voltage winding (1), low pressure winding (2)；
The temperature sensor (8) is sequentially fixed at winding major insulation outer surface from bottom to top using high-temperature insulating glue
10%, at 50% and 90%；
The temperature collecting module (9) is connected with the temperature sensor (8), for recording the real-time of winding layer insulation
Temperature；
Oil stream speed in flow velocity acquisition module (6) the acquisition experimental box (7)；Flow velocity acquisition module is placed in experimental box side wall
Oil communication pipeline (13) on；
The computer (10) is connected with the temperature collecting module (9) and the flow velocity acquisition module (6) respectively,
For later data processing；
The high-voltage winding (1) and low pressure winding (2) are respectively n sections and m sections, and n and m are determined by the corresponding winding number of plies divided by 6
It is fixed, if it is decimal, round up；The high-voltage winding (1) and low pressure winding (2) is top-down, and every section by 6 layer lines
Cake (11) is constituted, if its final stage is just built with actual layer number less than 6 layers；Line cake (11) in every section of winding uses conducting wire
Series connection；It is not electrically connected between every section of winding；
The high-pressure side DC power supplier (4) respectively includes n and m DC power supply with low-pressure side DC power supplier (5),
N and m is determined by the corresponding winding number of plies divided by 6, if it is decimal, is rounded up；Each DC power supply and one section of winding
It is connected, top-down numbering i=1,2 ... n-1, n and j=1,2 ... m-1, m；The output power of high-pressure side DC power supplyPH0For high-voltage winding D.C. resistance total losses；The output power of low-pressure side DC power supplyPL0For low pressure winding D.C. resistance total losses；
The winding major insulation (3) is from high-voltage winding (1) inside to total k layers of low pressure winding (2) outside, in major insulation outer surface
From mounting temperature sensor (8) at bottom to top 10%, 50% and 90%, installation site number is followed successively by 1,2,3, therefore senses
Device measured temperature Tab, wherein a is installation site number, and b is main insulating layer number, k layers total, is represented by：
The electro-insulating rubber block (12) is located at first layer insulating cylinder (301) and second layer insulating cylinder from high-voltage winding (1)
(302) at 5% position of spacing bottom, and along the circumferential direction the electro-insulating rubber block at mutual position in 90 ° is represented sequentially as M1
(1201), M2(1202), M3(1203) and M4(1204)。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710339081.1A CN107084803B (en) | 2017-05-15 | 2017-05-15 | Transformer winding major insulation temperature gradient tests system under stopping up of oil channel |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710339081.1A CN107084803B (en) | 2017-05-15 | 2017-05-15 | Transformer winding major insulation temperature gradient tests system under stopping up of oil channel |
Publications (2)
| Publication Number | Publication Date |
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| CN107084803A CN107084803A (en) | 2017-08-22 |
| CN107084803B true CN107084803B (en) | 2018-10-30 |
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| CN109270447A (en) | 2018-09-13 | 2019-01-25 | 广州供电局有限公司 | Transformer analog system and setting valve analog measurement method |
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| CN104766515B (en) * | 2015-03-30 | 2017-10-24 | 西南交通大学 | A kind of experimental provision and its experimental method for simulating tractive transformer heat |
| CN104749505B (en) * | 2015-03-30 | 2017-08-04 | 西南交通大学 | A kind of method that tractive transformer winding temperature rise is tested with oil flow rate degree relevance |
| CN105259482B (en) * | 2015-10-26 | 2018-01-05 | 西南交通大学 | Tractive transformer is layered paper oil insulation dielectric response experimental system |
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