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CN106374690B - Large generator stator bar insulation field repairing method - Google Patents

Large generator stator bar insulation field repairing method Download PDF

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Publication number
CN106374690B
CN106374690B CN201610880721.5A CN201610880721A CN106374690B CN 106374690 B CN106374690 B CN 106374690B CN 201610880721 A CN201610880721 A CN 201610880721A CN 106374690 B CN106374690 B CN 106374690B
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China
Prior art keywords
stator bar
insulation
ensure
damaged part
repairing
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CN201610880721.5A
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Chinese (zh)
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CN106374690A (en
Inventor
杨洲
潘延明
满宇光
孙永鑫
胡春秀
杨涛
张洋
施伟利
宋涛
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Harbin Electric Machinery Co Ltd
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Harbin Electric Machinery Co Ltd
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Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K15/00Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines
    • H02K15/0006Disassembling, repairing or modifying dynamo-electric machines
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K15/00Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines
    • H02K15/02Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines of stator or rotor bodies

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Power Engineering (AREA)
  • Manufacture Of Motors, Generators (AREA)
  • Insulation, Fastening Of Motor, Generator Windings (AREA)

Abstract

The present invention discloses a kind of large generator stator bar insulation field repairing method,This method uses low resin mica tape,Resin-rich mica tape,Room temperature curing epoxy glue,The materials such as preimpregnated glass silk ribbon (PG bands),Stator bar major insulation damaged part is repaired in the generator scene of the accident,By reasonable,Reliable renovation technique,It is completed in a short time main insulation of bar reparation,And ensure that stator winding disclosure satisfy that unit is long-term after repairing,Stablize,The requirement of reliability service,The technical process for the field repair that insulate simultaneously invention provides for large generator stator bar,Unit after all reparations puts into operation again,Winding insulation is had excellent performance after reparation,Reliably,Compared with previous generator Accident Handling Method,The method of the invention avoids splitting out for stator bar while ensureing repairing quality,It replaces,A large amount of rehabilitation cost is saved,The repairing duration is greatly shortened,With great economic benefit and social benefit.

Description

Large generator stator bar insulation field repairing method
Technical field:
The present invention relates to a kind of large generator stator bar insulation field repairing methods.
Background technology:
Error in the problems in the defects of design and manufacture, installation process, operation and maintenance may all cause large-scale power generation The damage of stator bar major insulation in the machine course of work, conventional restorative procedure are to use resin-rich mica tape and room-temperature curing epoxy Resin is wrapped up after filling and leading up damaged part, is cured, since mica content is less in resin-rich mica tape, solidification of epoxy glue The problems such as higher scene of temperature is difficult to be fully cured, it is difficult to ensure that the electrical strength after live major insulation reparation and long-term insulating properties Can, therefore be only capable of carrying away impaired stator bar out of stator coring groove, using resin-rich mica tape to impaired lighter stator line Stick carries out repair process, and processing can only often be scrapped by being damaged slightly serious stator bar, replace new bar, this restorative procedure Leading to the field repair of stator bar, that there are repairing qualities is poor, the repairing period is long, rehabilitation cost is high.
Invention content:
The object of the present invention is to provide one kind can improve reparation after insulating coating performance, so that it is met machine group leader The requirement of phase, stabilization, reliability service, but can to avoid the splitting out of stator bar, replace, save a large amount of rehabilitation cost, substantially Shorten the generator stator bar insulation field repair process of repairing duration.The technical solution that the present invention takes is:
A. stator bar damaged part is cleared up:Comprehensively careful cleaning is carried out to stator bar damaged part, first Damaged part is nearby cleared up with dust catcher, is then carefully wiped with the calico for dipping in absolute ethyl alcohol, and confirm absolute ethyl alcohol Completely next step operation can be carried out after volatilization;
B. the anti-halo layer of impaired place's circumferential location is polished off and is cleared up:With fine sandpaper by the anti-corona of impaired place's circumferential location Layer polishes off, and pays attention to ensure not cause to damage to stator bar major insulation as possible when polishing, when polishing should use dust catcher pair The Anti-Corona Material powder ground off is cleared up;
C. damaged part major insulation and its circumferencial direction reconditioning are gone out into taper:Damaged part major insulation reconditioning is gone out into taper, Then its circumferencial direction reconditioning is gone out into the smaller taper of the gradient, the wrapping processing after being filled in order to damaged part, reconditioning is completed Comprehensively careful cleaning is carried out afterwards;
D. mica flake is ground:The mica sheet stripped down on low resin mica tape is ground into mica flake, to ensure to repair The filling effect of breakage, the piece diameter of mica flake should be controlled in 2mm or less when multiple;
E. two component epoxy solidification glue is mixed:By the double component solvent-free room temperature curing with good, wide in range processing performance Epoxide-resin glue stirring is uniformly mixed, and when mixing pays attention to that curing agent should be poured slowly into epoxy resin, and keeps stirring, and mixes Gelatin viscosity after conjunction is relatively low, working life is longer, it is ensured that the smoothness that operation is repaired under any environmental condition is carried out with coherent;
F. mica flake is mixed with epoxide-resin glue:Appropriate mixed epoxide-resin glue is poured into ground mica It in fragment, stirs evenly, the mixture after stirring should be paste dope;
G. mixture is filled and is cured:Mixture is filled in damaged part, packed height is than stator bar major insulation Horizontal plane is slightly lower, and at least 6 hours are stood after filling to ensure that mixture is fully cured, to shorten mixture hardening time, is being filled out Filling position is heated with baking rifle after filling;
H. filling position is wrapped up and is cured:Filling is carried out using the resin-rich mica tape of epoxy resin-impregnated glue tight Cause wrapping as the insulation reinforcement to repairing position, to ensure the continuity of bar insulation, improve the mechanical strength of insulation, mica Band is wrapped up using half-lap, and repairing position after wrapping should be more slightly higher than its neighbouring major insulation horizontal plane, stands 6 hours to ensure epoxy Resin glue is fully cured;
I. feather plucking is carried out to wrapping position and cleared up:Feather plucking processing carried out to wrapping position with fine sandpaper, after feather plucking Comprehensively careful cleaning is carried out to entire restoring area;
J. brushing anticorona varnish and cure:In restoring area circumferencial direction brushing anticorona varnish, ensure anticorona varnish and stator bar Former anti-halo layer completely overlaps, and stands 12 hours to ensure that anticorona varnish is fully cured.
The present invention technical characterstic be:
1) there is high electrical strength at injury repair
Large generator stator bar insulation field repairing method proposed by the invention, main repair materials are high-purity Mica powder and solvent-free epoxy resin glue, it is ensured that electric property is excellent, reliable at injury repair;
2) bar has good appearance and size after repairing
Bar after being repaired using the method for the invention, injury repair region bar flat appearance are not in apparent Variation, it is ensured that bar has good appearance and size, does not interfere with bevel edge gap and the interlayer interval of winding;
3) substantially shorten repair time, save a large amount of rehabilitation costs
Compared with previous restorative procedure, the method for the invention avoids stator line while ensureing repairing quality Stick splits out, replaces, and has saved a large amount of rehabilitation cost, the repairing duration is greatly shortened;
4) use low resin mica tape as the main material of major insulation reparation --- compared with resin-rich mica tape, few glue mica Mica content in band is high, it is ensured that the electrical strength at repaired position;
5) room temperature curing epoxy glue --- the selected double component solvent-free room with good process performance is selected Have lower viscosity and longer working life, operational characteristic good, wide in range after warm curing epoxy resin adhesive mixing, it is ensured that The smoothness that operation is repaired under any environmental condition is carried out with coherent;
6) resin-rich mica tape is used continuously to wrap up the insulation reinforcement as restoring area --- resin-rich mica tape can bear compared with Big wrapping tension can ensure that bar is exhausted using the resin-rich mica tape of epoxy resin-impregnated glue to the restoring area wrapping that compact The continuity of edge improves the mechanical strength of insulation;
7) preimpregnated glass silk ribbon (PG bands) is used to carry out banding fixed to winding --- PG bands have good machinery strong Degree and processing performance carry out local banding fixed using PG bands to winding after reparation, and in external coating room-temperature curing epoxy tree Fat glue, it is ensured that firm, the stabilization of winding, it is ensured that unit can for a long time, reliably be run after reparation.
The method of the invention uses low resin mica tape, resin-rich mica tape, room temperature curing epoxy glue, preimpregnated glass The materials such as silk ribbon (PG bands) repair stator bar major insulation damaged part in the generator scene of the accident, by rationally, can The renovation technique leaned on is completed in a short time main insulation of bar reparation, and ensures that stator winding disclosure satisfy that machine group leader after repairing The requirement of phase, stabilization, reliability service, using the method for the invention, the unit after all reparations puts into operation again, repairs Winding insulation is had excellent performance, reliably afterwards, and compared with previous generator Accident Handling Method, the method for the invention is ensureing to repair Splitting out, replacing for stator bar is avoided while compound body amount, has saved a large amount of rehabilitation cost, repairing work is greatly shortened Phase has great economic benefit and social benefit.
Description of the drawings:
Fig. 1 is damaged bar schematic diagram
Fig. 2 anti-halo layers polishing schematic diagram
Fig. 3 major insulation taper reconditioning schematic diagrames
Fig. 4 mixtures fill schematic diagram
Fig. 5 damaged parts wrap up schematic diagram
Fig. 6 anticorona varnish brushing schematic diagrames
Specific implementation mode:
The present invention is a kind of large generator stator bar insulation field repairing method, is comprised the following steps that:
A. stator bar damaged part is cleared up:Bar damage situations are as shown in Figure 1, position shown in serial number 1 is fixed Sub- anticorona coating on bar, position shown in serial number 2 are the impaired place of bar, carry out comprehensively careful cleaning to the impaired place of stator bar 2, first The impaired place of bar 2 is nearby cleared up with dust catcher, is then carefully wiped with the calico for dipping in absolute ethyl alcohol, and confirm anhydrous second Next step operation can be carried out after alcohol volatilization completely;
B. the anti-halo layer 1 of 2 circumferential locations of the impaired place of bar is polished off and is cleared up:It will be damaged with fine sandpaper as shown in Figure 2 The anti-halo layer 1 for locating 2 circumferential locations polishes off, and position shown in serial number 3 is stator bar major insulation, pays attention to as possible ensureing when polishing Stator bar major insulation 3 is not caused to damage, when polishing should clear up the Anti-Corona Material powder ground off using dust catcher;
C. damaged part major insulation and its circumferencial direction reconditioning are gone out into taper:Damaged part major insulation reconditioning is gone out into taper, Its circumferencial direction reconditioning is then gone out into the smaller taper of the gradient, the wrapping processing after being filled in order to damaged part, reconditioning is completed Comprehensively careful cleaning is carried out afterwards, and reconditioning effect is as shown in Figure 3;
D. mica flake is ground:The mica sheet stripped down on low resin mica tape is ground into mica flake, to ensure to repair The filling effect of breakage, the piece diameter of mica flake should be controlled in 2mm or less when multiple;
E. two component epoxy solidification glue is mixed:By the double component solvent-free room temperature curing with good, wide in range processing performance Epoxide-resin glue stirring is uniformly mixed, and when mixing pays attention to that curing agent should be poured slowly into epoxy resin, and keeps stirring, and mixes Gelatin viscosity after conjunction is relatively low, working life is longer, it is ensured that the smoothness that operation is repaired under any environmental condition is carried out with coherent;
F. mica flake is mixed with epoxide-resin glue:Appropriate mixed epoxide-resin glue is poured into ground mica It in fragment, stirs evenly, the mixture after stirring should be paste dope;
G. mixture is filled and is cured:Filling effect position as shown in Figure 4 is mica powder, epoxy glue mixture 4, will be mixed Close object 4 be filled in damaged part, packed height is more slightly lower than 3 horizontal plane of stator bar major insulation, at least 6 hours are stood after filling with Ensure that mixture 4 is fully cured, to shorten 4 hardening time of mixture, filling position is carried out at heating with baking rifle after filling Reason;
H. filling position is wrapped up and is cured:It is wrapping area to wrap up effect position as shown in Figure 5, uses leaching The resin-rich mica tape of stain epoxide-resin glue compact wrapping as the insulation reinforcement to repairing position, to ensure bar to filling The continuity of insulation improves the mechanical strength of insulation, and wrapping position 5 is wrapped up using half-lap, and repairing position after wrapping should be than it Neighbouring major insulation horizontal plane is slightly higher, stands 6 hours to ensure that epoxide-resin glue is fully cured;
I. feather plucking is carried out to wrapping position 5 and cleared up:Feather plucking processing, feather plucking are carried out to wrapping position 5 with fine sandpaper Comprehensively careful cleaning is carried out to entire restoring area afterwards;
J. brushing anticorona varnish and cure:In restoring area circumferencial direction brushing anticorona varnish, ensure anticorona varnish and stator bar Former anti-halo layer 1 completely overlaps, and stands 12 hours to ensure that anticorona varnish is fully cured, it is as shown in Figure 6 that anticorona varnish applies brushing effects.

Claims (1)

  1. The field repairing method 1. a kind of large generator stator bar insulate, which is characterized in that include the following steps:
    A. stator bar damaged part is cleared up:Comprehensively careful cleaning is carried out to stator bar damaged part, first with suction Dirt device nearby clears up damaged part, is then carefully wiped with the calico for dipping in absolute ethyl alcohol, and confirm that absolute ethyl alcohol is complete Next step operation can be carried out after volatilization;
    B. the anti-halo layer of impaired place's circumferential location is polished off and is cleared up:The anti-halo layer of impaired place's circumferential location is beaten with fine sandpaper It grinds off, pays attention to ensure stator bar major insulation not to be caused to damage as possible when polishing, dust catcher should be used to grinding off when polishing Anti-Corona Material powder cleared up;
    C. damaged part major insulation and its circumferencial direction reconditioning are gone out into taper:Damaged part major insulation reconditioning is gone out into taper, then Its circumferencial direction reconditioning is gone out into the smaller taper of the gradient, the wrapping processing after being filled in order to damaged part, reconditioning is completed laggard The comprehensive careful cleaning of row;
    D. mica flake is ground:The mica sheet stripped down on low resin mica tape is ground into mica flake, when to ensure to repair The piece diameter of the filling effect of breakage, mica flake should be controlled in 2mm or less;
    E. two component epoxy solidification glue is mixed:By the double component solvent-free room-temperature curing epoxy with good, wide in range processing performance Resin glue stirring is uniformly mixed, and when mixing pays attention to that curing agent should be poured slowly into epoxy resin, and keeps stirring, after mixing Gelatin viscosity is relatively low, working life is longer, it is ensured that the smoothness that operation is repaired under any environmental condition is carried out with coherent;
    F. mica flake is mixed with epoxide-resin glue:Appropriate mixed epoxide-resin glue is poured into ground mica flake In, it stirs evenly, the mixture after stirring should be paste dope;
    G. mixture is filled and is cured:Mixture is filled in damaged part, packed height is than stator bar major insulation level Face is slightly lower, and at least 6 hours are stood after filling to ensure that mixture is fully cured, to shorten mixture hardening time, after filling Filling position is heated with rifle is dried;
    H. filling position is wrapped up and is cured:The packet that compacts is carried out to filling using the resin-rich mica tape of epoxy resin-impregnated glue It pricks as the insulation reinforcement to repairing position, to ensure the continuity of bar insulation, improve the mechanical strength of insulation, mica tape is adopted It is wrapped up with half-lap, repairing position after wrapping should be more slightly higher than its neighbouring major insulation horizontal plane, stands 6 hours to ensure epoxy resin Glue is fully cured;
    I. feather plucking is carried out to wrapping position and cleared up:Feather plucking processing carried out to wrapping position with fine sandpaper, to whole after feather plucking A restoring area carries out comprehensively careful cleaning;
    J. brushing anticorona varnish and cure:In restoring area circumferencial direction brushing anticorona varnish, ensure anticorona varnish and stator bar place where troops were originally stationed Dizzy layer completely overlaps, and stands 12 hours to ensure that anticorona varnish is fully cured.
CN201610880721.5A 2016-10-09 2016-10-09 Large generator stator bar insulation field repairing method Active CN106374690B (en)

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Publication number Priority date Publication date Assignee Title
CN106941244B (en) * 2017-05-17 2018-10-12 成都清威科技有限公司 A kind of switchgear insulation restorative procedure
CN109586519B (en) * 2017-09-29 2022-06-21 上海宝钢工业技术服务有限公司 Quick repair method for insulation damage of variable-frequency high-voltage motor winding
CN110912361A (en) * 2019-12-18 2020-03-24 国家电网有限公司 Method for repairing anti-corona layer of generator stator bar
CN111725961A (en) * 2020-07-24 2020-09-29 哈尔滨电机厂有限责任公司 Method for repairing damaged low-resistance anti-corona layer of generator stator bar notch
CN112968577B (en) * 2021-02-23 2022-01-21 中国长江电力股份有限公司 Giant hydro-generator stator core fusing repair device and repair method
CN113783385A (en) * 2021-10-11 2021-12-10 哈尔滨电机厂有限责任公司 Method for repairing stator winding interphase corona condition
CN113922601B (en) * 2021-11-11 2024-03-15 哈尔滨电机厂有限责任公司 Local replacement process method for upper-layer bar of large-sized gas turbine generator stator

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SU1356128A1 (en) * 1982-10-11 1987-11-30 Г.С.Дегиль и Б.Г.Дегиль Method of reparing high-voltage insulation of stator windings of electric machines
SU1629946A1 (en) * 1988-08-09 1991-02-23 Череповецкий Металлургический Комбинат Им.50-Летия Ссср Technique for repairing electrical machine windings
CN1980011A (en) * 2005-12-09 2007-06-13 江苏锡安达防爆股份有限公司 High-voltage motor stator winding winding breakdown repairing method
CN101145714A (en) * 2007-08-15 2008-03-19 山东齐鲁电机制造有限公司 Repair technology for penetrated high-voltage motor stator coil of vacuum pressure soakage
CN202353403U (en) * 2011-12-13 2012-07-25 中国西电电气股份有限公司 Stator coil repairing structure for large impact generator set
CN104247222A (en) * 2012-02-20 2014-12-24 西班牙阿尔斯通可再生能源有限公司 Methods of repairing a winding in a generator, and kits for making a substitute coil
JP5776300B2 (en) * 2011-04-20 2015-09-09 トヨタ自動車株式会社 Winding and coil forming method, and coil damage repairing method

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US20040202782A1 (en) * 2003-04-14 2004-10-14 General Electric Company Methods for repairing insulating material

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU1356128A1 (en) * 1982-10-11 1987-11-30 Г.С.Дегиль и Б.Г.Дегиль Method of reparing high-voltage insulation of stator windings of electric machines
SU1629946A1 (en) * 1988-08-09 1991-02-23 Череповецкий Металлургический Комбинат Им.50-Летия Ссср Technique for repairing electrical machine windings
CN1980011A (en) * 2005-12-09 2007-06-13 江苏锡安达防爆股份有限公司 High-voltage motor stator winding winding breakdown repairing method
CN101145714A (en) * 2007-08-15 2008-03-19 山东齐鲁电机制造有限公司 Repair technology for penetrated high-voltage motor stator coil of vacuum pressure soakage
JP5776300B2 (en) * 2011-04-20 2015-09-09 トヨタ自動車株式会社 Winding and coil forming method, and coil damage repairing method
CN202353403U (en) * 2011-12-13 2012-07-25 中国西电电气股份有限公司 Stator coil repairing structure for large impact generator set
CN104247222A (en) * 2012-02-20 2014-12-24 西班牙阿尔斯通可再生能源有限公司 Methods of repairing a winding in a generator, and kits for making a substitute coil

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