鍋爐電氣1-11變壓器部分

1、第 1 章主變壓器TRANSFORMER400000220U1CONTENTS1.roductionApplicationTechnical dataTransformer comition ponents designControl and measuring instruments and protective deviMarking and sealingPacking9. Transporion, unloading, storage, mounting and commising1.RODUCTION1.1 The present Technical Description (TD)

2、 is-400000/220 Y1 Transformer.ended for studying the1.2 When studying the transformer design, besides the present TD, use theoperating1.3 TD does own similaration ,shipped with the transformer.not includes,information on the components, having theird together with the products.2.APPLICATION2.1Thetwo

3、-winding-400000/220Y1Transformeriserthree-phase,withOFAFCoolingsystem(forcedairandoilcircu-ion),with on-load tap-changing at HV side and is designed foroperation in a unit with generator of 325 MWer.2.2 Climatic verof the transformer-moderate, installa-tion-outdoor.43um ambient temperatureminus28up

4、to 1920.3 m above sea levelMinimum air temperatureAltitude of the transformer installation46Average relative humidity89um relative humidityTECHNICAL DATARated capacityRated voltageHV winding LV wingingOn-load voltage regulation (OLTC)400000 kVA241.5 kV 20Kvat HV sideplus 6x1.25Regulation rangeminus

5、10 x1.2550Hz YN/d-11 780Kw3.4 Rated frepuency3.5 Vectroup3.6 Short circuit losses14190Kw3.7 Impedance voltage3.8 No-load losses0.33.9 No-load currentAdmissible neutral current when heating the transformerType of cooling systemMovement of the transformer is carried out by railway with tracks:for long

6、itudinal movementfor transverse movement1100AOFAF1435mm3x1435mm4.TRANSFORMER COMITIONThe transformer consists of the following components (assembly units):Core and coils assembly, including:core framewindingsinsulation1 pc9 pcs1 set1 pc3 pcs1 pcs3 pcs1 set1 set4.1.2with fittingsHV bushingsNeutral bu

7、shingLV bushingsCooling systemConservator installationControl and measuring and protective apparatusThe transformer delivery set includes also:1 set-operatingation;-container and packing;-spare parts.COMPONENTS DESIGNThe transformer general view, arrangementof componentsandelements, overall, mountin

8、g dimendrawing VBIE.672848.020 OD.s and masses are given in outline5.2Thetransformercoreandcoilsassemblyisasinglestructure ,including in assembled view the core, windings insulation and taps.5.3 The transformer core consists of magnetic system and elementsproviding for its bracing and insulation, as

9、 well as serving for fasteningthewindings.Thecoreisfive-leg,laminatedwithnitrejooflaminations. Laminations are made of cold-rolled electricalthermal-resistant insulation coating. The core is laminated insteel with one sheet.with yokeBracing is done with glass tbandages. Yokes are pressedbeams, which

10、 are braced with semi-bandages made of steel.5.4 Windings are located on the core legs concentrically in the following order from the leg:LV winding-screw-type, five-way, two-layer.HV winding-continuous, with leadRW winding-screw-type, two-layer.o middle, input zone iserlaced.ALL windings are of rec

11、tangular section copper conductor.Delta-connection of LV windings is done on bushings inside the.Star-connection(non-detachably).ofHVwindingsisdoneinsidethe5.5 Insulation. Pressing of windings.Design of main insulation is oil-barrier type made of cardboard cylinders, separated with spacers.Windings

12、are pressed with pressing screws.Pressing force after drying the core and coils assembly:LV windings HV windingsRW windings-471 KN;429 kN;160 kN.Taps are made of winding conductor, copper flexible connections, copper buses, serving for connection or windings in electrical diagram, as well as for con

13、nection with relevant bushings and tap-changer.Voltage regulationVoltage regulation is on-load at HV side d UCCRN-650/1200/IV S.The tap- changer is located at the provided.5.8 Installation of core and coils assemblyThe core and coils assembly is installedith the tap-changer typeend. Inspection holes

14、 arehein the.onto insulatingbaskets made of cardboard. Its installation is fixed by two studs, located inthebottom.5.9 For the period of the transformer transporion and operation thecore and coils assembly is fastenedheby the following way: intop part in longitudinal and transverse directions by ins

15、talling screwsostops.Acs to screws is through spel holes at theuppart.At lower part the core and coils assembly is fastened in longitudinaldirection with screws and wedges. Acs to screws and wedges issible after removing theuppart.5.10 Earthing of the core and coils assembly is done by the following

16、way:Thebottom is fitted with two branch pipes, in which bushings arelocated. Buses from lower HV yoke beam andt from lower LV yokebeam, as well as bus from theare connected separay to the bushingpins. This allows to measure the yoke beams insulation, notremoving theuppart.is of bell-type, consisting

17、 of two parts: upper5.11 The transformer( bell) and lower (bottom).Thedesign provides for the required mechanical strengt:lifting the completesting;y assembled transformer;commistransporing;ion.5.12 Lead-out of neutral and linear ends of HV windings is performedwith bushings of Swedish firm “ABB”.Bu

18、shings type GOM 1050 Cat. No LF125060-S are installed at HV side,bushing type GOB 650/1250 Cat. No LF123194-M is installed at neutral.Bushings type IIHTY-24/18000-T1 with reinforced external insulationare installedV side.5.13 Mounting of conservatorThe conservator volume provides for constant presen

19、ce of oil in i operation duties of the transformer.allThe transformer conservator is provided with a flexible envelope,er oil level gauge, air breathers with silica gel.poInstallation of a sionary ladder is provided for maenance of thetransform5.14 The cooling devirotection devi.transformer cooling

20、system is OFAF, consisting of eight, suspended onto the.Automatic control of the cooling system provides for:1) switching on electric pumps oftransformer;group at energizing the2) switching on electric pumps of second group at reaching 50of thetransformer rated capacity;3)switching on fan electric m

21、otors ofgroup at reaching thewinding temperature 75;4)switching on fan electric motors of second group at reaching thewinding temperature 75;Control apparatus of the cooling system is installed in weathroofcabinet. Signaling informs about operation and faults of the cabinet andthe cooling system. Li

22、st of signals is given in thecontrol cabinets.ation forThe cooling system control cabinet is installed on its own foundation.The installation site iected by the Customer.6.CONTROLANDMEASURINGINSTRUMENTSANDPROTECTIVE DEVI6.1 Current transformers, installed on bushings, serve for measurements and prot

23、ection of the transformer.6.2Thepocompartment iseroillevelgaugeatthetransformerconservatorended to indicate the oil levelhe conservator and toum oil levels in theclose the, signaling circuit at minimum andconservator.The similar oil level gauge is installed at the conservator compartment for the tap

24、-changer.6.3 The protective relay has two pairs of elements.One pair of contacts is used fiving signal about accumulation of gasin it. Another pair of contacts is used for r tripthe transformer atensive gas liberation orow oil levelhe gas relay. The protectiverelay has the gas sampling device withou

25、t deenergizing the transformer.6.4 The safety valve is designed to prevent the transformerdestruction at sharp rise ofernal prere above admissiby ejectionof oil trip6.5to outside. The valve the transformer.Winding temperaturehas contacts, which shall be connectedforindicators are designed for measur

26、ingthearewinding temperature at all operation duties of the transformer andinstalledhe marshalling kiosk on the transformer.6.6 The oil temperature indicator is designed for measuring the top oiltemperature and is installedhe marshalling kiosk .6.7 Control cables from control and protective instrume

27、nts are broughto the marshalling kiosk, which is fixed on the transformer.6.8 Automatic circuit breakers on motors and electric pumps of thecooling system are designed for protection from two phase operation andshort circuit currents. Circuit breakers are installedcontrol cabinets.he cooling systemM

28、ARKING AND SEALINGThe transformer is provided with :The name-plate, containing the technical data and masses of the transformer;The name-plate, containing the technical data of current transformers, marking of their ends;The plate with the valves location diagram;The plate with the diagram of termin

29、als and vector diagram;The owners plate.ernal arrangement and connection of7.2 The transformer is provided with inscriptions of slinging spots, gravitycentre, earthing and plaof hydraulic jacks.7.3 For the period of the transformer transporion and storage thefollowing deviare sealed:Oil sampling dev

30、ice;Butterfly valve for draining oil from the transformer.PACKINGThetransformerandlarge-size componentsdismantledforthetransporion period are shipped without package.82 Dismantled assembly units and parts of the transformer, as well asoperationation are packedhe container, providing for theirsafety

31、during transporion and storage.Transport tare is the wooden cases or other spel kinds of packages.Storage conditions of packed and dismantled units and parts of thetransformer under shed areended for permissible term of preservationof no moren one year.9. TRANSPORION, UNLOADING, STORAGE, MOUNTINGAND

32、 COMMISING9.1ex 9.2The transformer is transported being filled with dry nitrogen withsive prere from 20 to 25 kPa.The transformer may be transported on railway transporter of jotype and by sea or by road.9.3 Unloading, storage, mounting, commising and operation of thetransformershallbecarriedoutinVB

33、IE.672848.020 OI.compliancewithInstructions第 2 章 廠用變和啟備變目錄概述使用環(huán)境條件主要技術數(shù)據(jù)及技術要求備用件和工具其它要求技術文件 概述本規(guī)程以中國東方電所（DEC）和西南電力設計院與沈陽變壓器公司就 ARAK 電廠配套的高壓廠用變和啟備變達成技術協(xié)議為基礎編制而成。未盡事宜詳見技術協(xié)議。2使用環(huán)境條件2.1 環(huán)境溫度最高溫度最低溫度最熱月平均溫度36.22.2 海拔高度 1920.32.3 最大風速2.4 平均相對濕度，最大相對濕度2.5 基本烈度：水平度為 0.252.6 最大雪厚：2.7 污穢等級：級（高壓側(cè)、低壓側(cè)、及中性點套管爬距為

34、最高工作電壓） 主要技術數(shù)據(jù)及技術要求3.1 使用標準1kV 以上變壓器套管IEC137套管IEC35-A:38：標準電壓IEC絕緣配合，第一和第三部分IEC70:76：電力變壓器，第部分IEC99.1：避雷器IEC185：電流互感器IEC214：有載調(diào)壓分接頭開關IEC296：絕緣油IEC354：變壓器加載原則IEC551：變壓器噪聲水平測試IECNEMA TRI-1971:噪聲和無線電干擾中性點接地電抗器IEEE 32:ANSI C 75.16: 限流電抗器相應的中國。3.2 主要技術參數(shù)3.2.1 廠用變壓器）型式：戶外型，三相雙線圈低壓繞組油浸風冷卻無載調(diào)壓銅芯低損耗變壓器。2）系統(tǒng)最

35、高電壓：23KV3）額定容量高壓廠用工作變：400002020MVA4）額定電壓：20KV5）額定頻率：50Hz6）相數(shù)：三相7）空載電流：0.68）半穿越阻抗電壓（正序，以變壓器全容量為基準）高壓廠用工作變：15允許偏差：5 制造廠應補充提供零序阻抗電壓。9）調(diào)壓方式：高壓側(cè)無勵磁調(diào)壓調(diào)壓范圍：5510）中性點接地方式：經(jīng)電阻接地11）冷卻方式：ONANONAF12）制造廠應提供零序電流值（單相短路時）及允許時間13）連接組標號：D，yn1yn114）極性：減極性15）套管電流互感器：只允許負偏差0.350.516）效率及損耗效率：（在額定功率下，在滿載和 50的負載下）

36、效率不低于 99.52（不包括雜散損耗）。損耗：（在額定功率，額定電壓下，滿載時損耗）。制造廠提供在不同負載及功率條件下的效率和損耗表。所有的損耗值均為最大值。損耗高廠變空載損耗（kw）33負載損耗（kw）161總損耗（kw）194裝設位置型號電流變比每相臺數(shù)準確級二次負載（VA）高廠變高壓側(cè)20kv1500/5A1500/5A1500/5A111592059200.5+305017）絕緣水平注：低壓側(cè)絕緣電壓應考慮到高壓側(cè)傳遞過電壓的影響。18）套管所有載流螺栓或螺柱的直徑應不低于 10mm。賣方應提供用于分別連接各繞組到線或封閉母線的所有端子和法蘭等連接件。高低壓套管或電纜端子的相序排列應

37、為：從高壓側(cè)往低壓側(cè)看，從左到右按，順序排列。當裝設中性點套管時，其布置按同樣方法時，應是在最左端。套管絕緣水平注：低壓側(cè)絕緣電壓考慮到高壓側(cè)傳遞過電壓的影響。套管爬距：高壓側(cè) 69cm低壓側(cè) 22.8cm裝設位置工頻耐受電壓雷電沖擊全波電壓（kw）（峰值）（k）干式濕式(1.2/50us）高壓側(cè)57(50)125低壓側(cè)32(30)75裝設位置工頻耐受電壓雷電沖擊電壓（kw）（k）全波(1.2/50us）截波高壓側(cè)55125140低壓側(cè)（6.9kw）356065套管額定電流：制造廠按變壓器容量及導線連接形式配置。制造廠應提供套管的全部型式試驗及出廠試驗。19)端子接法與端子拉力高壓側(cè)套管與離相

38、封閉母線相連，相間距離 1075mm，低壓套管與廠用共箱封閉母線相連，變壓器廠與封閉母線廠密切配合，互相提出要求。3.2.2 啟動備用變壓器技術參數(shù) 型式：戶外型，三相雙線圈低壓繞組油浸風冷（ONAF）銅芯低損耗變壓器，有載調(diào)壓。 額定容量:63/35-35 MVA 額定電壓:23081.25/6.9-6.9kV 額定頻率:50Hz 系統(tǒng)最高電壓:252kV 相數(shù):三相 空載電流:0.7% 半穿越阻抗電壓 23%(正序阻抗,以全容量為準),允許偏差5%制造廠應提供零序阻抗電壓。3.2

39、.2.9 中性點接地方式：高壓側(cè)經(jīng)刀開關接地，低壓側(cè)以電阻接地。0 冷卻方式：ONANONAF1 制造廠應提供零序電流（單相短路時）及允許時間2 連接級標號：YN，yn0yn0，d3 極性：減極性4 效率及損耗a)效率：（額定功率下，在滿載和 50的負載下）效率不低于 99.48（不包括雜散損耗）。b）損耗：（在額定功率，額定電壓下，滿載時損耗）?？蛰d損耗：52kV負載損耗：270kV總損耗：322kV制造廠應提供在不同負載及功率條件下的效率和損耗表。5 套管電流互感器裝設位置型號電流變比準確級二次負載（VA

40、）每相數(shù)量（只）高壓側(cè) 230kV2005A0.52512005A5P20302高壓側(cè)中性點2005A5P20256 絕緣水平注：低壓側(cè)絕緣電壓應考慮到高壓側(cè)傳遞過電壓的影響。7 套管所有載流螺栓或螺柱的直徑應不低于 10mm。賣方應提供用于分別連接各繞組到線右封閉母線的所有端子和法蘭等接件。高低壓套管或電纜端子的相序排列應為：從高壓側(cè)往低壓側(cè)看，從左到右按 A，B，C 順序排列。當裝設中性點套管時，其布置按同樣方法時，應是最左端。a)套管絕緣水平裝設位置雷電沖擊全波試驗電壓（kV）（峰值）操作波試驗電壓（kV）（峰值）一分鐘工頻耐受電壓（kV）（1.2/50 s

41、）（250/2500 s）干式濕式高壓側(cè)（220kV）950495（395）裝設位置一分鐘式頻耐受雷電沖擊電壓（kV）（有效值）電壓（kV）（有效值）全波（1.2/50 s）截波高壓側(cè)220 kV3959501050高壓側(cè)中性點200400低壓側(cè)（6.9 kV）306065注：低壓側(cè)套管絕緣電壓應考慮到高壓側(cè)傳遞過電壓的影響。b)最小爬距：高壓側(cè)（230kV）：7560mm中性點（110kV）：3780mm低壓側(cè)（6.9kV）：228mmc)端子拉力：安全系數(shù)：長期作用負載時 2.5，短時作用負載時 1.67。d)局部放電：1）高壓套管（工廠試驗）：在 1.5252kV 電壓下，局部放電小于

42、10PC。2）230kV 套管（型式試驗）：安國標 GB410908 及 IEC 標準。e）套管額定電流，廠家根據(jù)變壓器容量及導線連接形式配置。f）制造廠應提供套管的全部型式試驗及出廠試驗。8 調(diào)壓方式：高壓側(cè)中性點有載調(diào)壓。部位水平方向垂直方向高壓套管2000N700N高壓側(cè)中性點套管1000N400N低壓套管與共 6.9kV 共箱封閉母線配套，由制造廠提供高壓側(cè)中性點450200低壓側(cè)（6.6kV）6032（23）調(diào)壓范圍： -10%+10%限值：當強迫冷卻設備故障時，變壓器應能維持滿負荷運行3.2.310 分鐘，而不會引起縮短變壓器和在任何情況下計算最熱點溫度不超過 140

43、（該值應考慮 ICD354（appendix B）對環(huán)境溫度的限制）。廠用變和啟備變在額定輸出容量時的：制造廠應提供試驗以證明變壓器各部分無局部過熱現(xiàn)象。各變壓器能連續(xù)運行的額定值應以電廠主廠房外的環(huán)境空氣溫度為基礎。變壓器在任意抽頭應能以額定容量連續(xù)運行，而不超過IED76 的規(guī)定，該應適于現(xiàn)場冷卻空氣溫度和高程。對抽頭范圍超過5 的變壓器，在5抽頭帶額定容量連續(xù)運行時，繞組不超過主抽頭時的 4，而在10 或更高抽頭時，不超過 8。在指定的電壓和頻率變化和任意潮流方向的任意變比，以及非抽部位限值測量方法線圈65電阻法頂層油55溫度計法油箱及結(jié)構(gòu)件表面80熱電偶法鐵芯表面75熱電偶法頭繞組維持

44、在指定電壓下，各變壓器應能在額定輸出下連續(xù)運行。3.2.4 電暈和無線電干擾在 1.1 倍最大相電壓下，在晴朗的的夜晚戶外應見不到電暈產(chǎn)生。制造廠應根據(jù)NEMATRI1971 提供在晴朗天氣戶外無線電干擾的水平。3.2.5 過激磁能力直接接于發(fā)電機的變壓器，在突然甩負荷的特殊情況下，應能在高于正常額定電壓 35時，連續(xù)運行不低于一分鐘。過勵磁能力如下表：（以額定電壓為基準，在額定頻率下，以下數(shù)據(jù)參考，廠家應以本文所列的相關標準為準）制造廠應在合同簽訂后四個月內(nèi)提供變壓器過激磁能力曲線。3.2.6 過負荷能力：在發(fā)電機機端電壓在額定值5 范圍內(nèi)變化時，變壓器應能輸出額定容量。廠家應以本文所列的相

45、關標準為準，在合同簽訂后四周內(nèi)向買方運行條件空載滿載過電壓倍數(shù) 允許運行時間51.051.11.3連續(xù)20min 1min連續(xù)10min10s提供變壓器允許過負荷能力的準確資料。在任何過負荷運行情況下，變壓器線圈的最高溫度應不超過 140。3.2.7短路承受能力變壓器在滿負載及任何抽頭位置情況下，應能承受外部故障短路電流 40kA，3 秒無損壞，且線圈的最高溫度不超過 250（短路條件符合 IEC-76 的規(guī)定）。3.2.8 局部放電：在 1.5 倍最高相電壓下，局部放電量小于 500PC，出廠時應向買方提供各點實測值。變壓器放電和金相試驗應符合相關規(guī)范和方法。噪音水平按N

46、EMATR11971 標準所述執(zhí)行。3.2.9諧波抑制變壓器設計應特別注意抑制諧波，尤其是三次諧波和五次諧波，以減小波形變形和任何可能的高頻擾動，或在不同位置變壓器中性點之間形成環(huán)流對通信回路的影響。3.2.10 制造廠應提供散熱器運行和備用臺數(shù)。并按下表填寫在不同散熱器臺數(shù)下，所允許的運行負荷及滿載時允許運行時間、線圈溫度、油溫。 廠用變壓器 啟動備用變壓器制造廠應提供冷卻裝置（風機等）的控制、保護設備以及變壓器保護、測量連接用的端子箱。散熱器能承受 2bar 超壓，可拆卸，帶有關斷閥，并有“閥開”，“閥閉”狀態(tài)。散熱器的設計應消除凹坑，以免沉積雜質(zhì)或使油漆膜

47、不完整，散熱器管不能直接與支撐管材焊接。需要時，各散熱器與變壓器之間為橈性連接。散熱器管道的每一段均有排油閥和通氣閥。散熱器投入百分比0255075100允許運行負荷（）負載時允許運行時間（分鐘）線圈溫度（）油溫（）散熱器投入百分比0305080100允許運行負荷（）負載時允許運行時間（分鐘）線圈溫度（）油溫（）3.2.11 變壓器輔助電源電壓OLTC 和風扇電機的三相交流電壓：400V冷卻系統(tǒng)和OLTC 的控制回路單相交流電壓：230V3.2.12 制造廠應提供變壓器油型號的性能。變壓器的工藝、設計和所用材料應最大限度地減小油的酸化和其它腐蝕。油的牌號：IEC29682class IIA含水

48、量：0.001含氣：0.1耐壓等級：45kV以上參數(shù)應滿足本文所述標準的要求。3.2.13 變壓器繞組的匝間工作場強：2kVmm。3.2.14 硅鋼片的牌號。3.2.15 變壓器的鐵芯接地應通過小套管外引接地。3.2.16 油箱：主油箱包括分接頭調(diào)節(jié)艙，散熱器。當油排空時，應能承受 760mm柱壓力（即不小于大氣壓 1kg/cm2）。油箱蓋上有一接地極。變壓器油箱蓋通過螺栓和墊圈與主油箱相連。油箱蓋上帶有一個裝有溫度計、繞組溫度指示器和水銀球的盒子，安裝在最高油溫位置，移動溫度指示器時不必降低油箱內(nèi)油面。手孔與人孔在分接頭機構(gòu)、電流互感器及所有套管連接底端的合適位置。人孔應允許 500mm 直

49、徑的球體進入，所有蓋子打開至少有 15mm高，并有與油枕相連的氣體管。油箱設計及連接管安裝應考慮氣體有效進入瓦斯繼電器。當有氣體析出時，應直接快速地動作瓦斯繼電器。油枕蓋內(nèi)至少有兩處氣體點，以防止氣體被限制而使壓力升高。每一油箱應有如下措施：適于變壓器帶油起吊的起吊環(huán)或吊鉤。在可觸及的位置至少有 4 個最低高為 300mm 的支撐物，通過液壓裝置和千斤頂能使變壓器升高或降低。在油箱的四角，距基礎不超過 750mm 的水平方向應有鋼板，其上有 50mm 的鉆孔，使變壓器可以朝任一方向移動。所有進入油箱的管道應有帶油密封的關閉閥，并有打開和關閉位置的正確指標。吸收性物質(zhì)有能作油封連接件。油箱應密封

50、并采用真空注油，油箱經(jīng)下列試驗無滲漏和性變形。抽真空殘壓：1mmHg超壓試驗：承受 2 倍油枕油面的油壓 24 小時。注明噴油方向：向外各變壓器應裝設足夠?qū)嵙Φ膲毫ρb置。3.2.17 鐵芯鐵芯的磁路：磁路的設計應避免靜電、其內(nèi)部或?qū)Φ囟搪吠ǖ赖男纬?、以及由于鐵芯層疊鐵片的漏磁引起的局部過熱。應仔細檢查，確保其疊鐵片平整，以使組裝成的鐵芯不變形。層疊鋼片應用冷軋，紋理同向的硅鋼片。每一層疊片應用在壓力的熱油下不易損壞的材料。鐵芯的機械結(jié)構(gòu)：鐵芯、構(gòu)架、固定裝置和變壓器的主結(jié)構(gòu)應加強設計使其能承受由于、安裝、運行引起的沖擊和振動。3.2.18 繞組變壓器為銅繞組，其過載和短路特性與相應電源匹配。分

51、接頭饒組盡可能保證各電壓等級的電磁平衡和沖擊耐受能力。變壓器邊緣上的繞組應用寬度不超過其厚度 6 倍的導體繞成。變壓器繞組和端子應能承受在、搬運、晃動、開斷操作或其它暫態(tài)過程的晃動。3.2.19 絕緣變壓器絕緣材料的使用應保證變壓器在環(huán)境條件下能連續(xù)運行，并避免運行中出現(xiàn)軟化、滲漏、收縮或損壞等。變壓器在所有指定條件和負荷下連續(xù)運行時，在熱油作用下絕緣材料不應出現(xiàn)收縮、裂紋、碳化或脆化。等級有載調(diào)壓分接頭。3.2.20 接地除獨立的鐵芯疊片、鐵芯螺栓和鐵芯夾板外，變壓器的所有金屬部件應維持在一個固定的電位水平。磁路一點接地，通過一個可動連接片接到夾緊結(jié)構(gòu)上，該連接片可通過油箱蓋上的檢查孔檢查。

52、連接片的連線應與主接地連線位于同一側(cè)。有絕緣分段的磁路結(jié)構(gòu)應在各段設一獨立的連接片。頂部主夾緊結(jié)構(gòu)由一根銅帶接到箱體，底部夾緊結(jié)構(gòu)的接地可直接接到箱底或接到頂部夾緊結(jié)構(gòu)。除獨立的線圈固定環(huán)外，所有接地線截面應不小于 80mm2。疊片間的連線，在與鐵芯有緊密熱接觸的地方，其截面可減20 mm2。變壓器鐵芯接地應通過套管穿過油箱，用銅帶直接接地。各接地端子應能承受變壓器低壓側(cè)電流 30s，端子位于靠近油箱底部四角的地方。3.2.21 無載調(diào)壓開關對指定用無載調(diào)壓開關的變壓器，無載抽頭設于高壓繞組，各抽頭額定值應為容量。抽頭控制由無載分接開關來進行。該開關帶有易于從地面操作的操作手柄和抽頭位置指示器

53、，各抽頭位置應可鎖定。3.2.22 有載調(diào)壓開關啟備變有載調(diào)壓開關為德國 MR 開關。為電控制的電阻型負載分接頭變換裝置。各分接位置均應能帶滿負荷。調(diào)節(jié)開關安裝有分隔艙中，以便其絕緣與變壓器油完全。每個油浸式調(diào)壓艙中設有一個帶有低油位觸點的磁性油位表，壓力閥，充油，濾油壓力閥。調(diào)節(jié)開關艙中不帶跳閘觸點的繼電器，跳閘觸點也可設在壓力釋放閥上，脫水式呼吸閥安裝在眼視水平上，呼吸閥為硅膠干燥劑式。如變壓器調(diào)節(jié)裝置有單獨油箱，則應設有單獨的帶低油位觸點的油位計，充油和排油閥，管道系統(tǒng)，帶跳閘觸點的壓力裝置應設置在到儲油箱的管道中。所有油位計能站在地面上觀察讀數(shù)。分接頭控制屏應滿足 IP55 的要求，其內(nèi)應有如下裝置：分接頭機構(gòu)位置指示器機構(gòu)操作記數(shù)器手動，電動控制“升降”按鈕或開關“遠動就地”選擇開關分接頭調(diào)節(jié)電機保護和控制回路設備端子箱從廠用電源引接的門燈恒溫控制防凝加熱器3.2.23 賣方應與封閉母線制造廠密切配合，以保證系統(tǒng)的正確連接。3.2.24 變壓器的各組件在制造廠內(nèi)預組裝一次，打好標記保證在現(xiàn)場裝配中能順利進行。3.2.25 變壓器廠應采