EN 50708-2-1-2020 电力变压器 欧洲附加要求 第2-1部分：中型电力变压器

EUROPEANSTANDARDNORMEEUROPÉENNEEUROPÄISCHENORM

EN50708-2-1

May2020

ICS29.180SupersedesEN50588-1:2017(PART)andallofits

amendmentsandcorrigenda(ifany)

EnglishVersion

Powertransformers-AdditionalEuropeanrequirements:Part2-

1Mediumpowertransformer-Generalrequirements

Transformateursdepuissance-Exigenceseuropeennes

supplémentaires:Partie2-1Transformateursdemoyenne

puissance

Tobecompleted

ThisEuropeanStandardwasapprovedbyCENELECon2019-10-09.CENELECmembersareboundtocomplywiththeCEN/CENELEC

InternalRegulationswhichstipulatetheconditionsforgivingthisEuropeanStandardthestatusofanationalstandardwithoutanyalteration.

ManagementCentreortoanyCENELECmember.

Up-to-datelistsandbibliographicalreferencesconcerningsuchnationalstandardsmaybeobtainedonapplicationtotheCEN-CENELEC

ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).AversioninanyotherlanguagemadebytranslationundertheresponsibilityofaCENELECmemberintoitsownlanguageandnotifiedtotheCEN-CENELECManagementCentrehasthesamestatusastheofficialversions.

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Denmark,Estonia,Finland,France,Germany,Greece,Hungary,lceland,Ireland,Italy,Latvia,Lithuania,Luxembourg,Malta,the

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CEN-CENELECManagementCentre:RuedelaScience23,B-1040Brussels

◎2020CENELECAllrightsofexploitationinanyformandbyanymeansreservedworldwideforCENELECMembers.

Ref.No.EN50708-2-1:2020E

2

EN50708-2-1:2020(E)

Contents

Europeanforeword 3

Introduction 4

1Scope 5

2Normativereferences 5

3Termsanddefinition 5

4Servicecondition 5

5Ratingandgeneralrequirements 5

5.1General 5

5.1.1HighestvoltagesforequipmentforwindingwithUm>1,1kV 5

5.1.2RatedvoltageforwindingwithUm≤1,1kV 5

5.1.3Tapping 6

5.1.4Connectiondesignationsforthreephasetransformers 6

5.2EnergyPerformance 6

5.2.1General 6

5.2.2Transformerswithspecialrequirements 9

6Ratingplate 11

7Tolerancesduringfactoryacceptancetests 11

8Tests 11

9Accessoriesandfittings 11

10Capitalizationlosses 11

11Transformersoverhaul 11

AnnexZZ(informative)RelationshipbetweenthisEuropeanStandardandtheecodesignrequirementsofCommissionRegulation(EU)No548/2014of21May2014anditsamendmentNo2019/1783of1October2019onimplementingDirective2009/125/ECoftheEuropeanParliamentandoftheCouncilwithregardtosmall,mediumandlarge

powertransformersaimedtobecovered12

EN50708-2-1:2020(E)

3

Europeanforeword

Thisdocument(EN50708-2-1:2020)hasbeenpreparedbyCLC/TC14"Powertransformers".

Thefollowingdatesarefixed:

·latestdatebywhichthisdocumenthas(dop)2020-11-22

tobeimplementedatnationallevelby

publicationofanidenticalnational

standardorbyendorsement

·latestdatebywhichthenational(dow)2023-05-22

standardsconflictingwiththisdocument

havetobewithdrawn

ThisdocumentsupersedesEN50588-1:2017andallofitsamendmentsandcorrigenda(ifany).

Attentionisdrawntothepossibilitythatsomeoftheelementsofthisdocumentmaybethesubjectofpatentrights.CENELECshallnotbeheldresponsibleforidentifyinganyorallsuchpatentrights.

ThisdocumenthasbeenpreparedunderamandategiventoCENELECbytheEuropeanCommissionandtheEuropeanFreeTradeAssociationandsupportsessentialrequirementsofEUDirective(s).

FortherelationshipwithEUDirective(s)seeinformativeAnnexZZ,whichisanintegralpartofthisdocument.

EN50708-2-1:2020(E)

4

Introduction

Forthepurposeofthisdocument,therequirementsofthegeneralEN50708-1-1:2020apply.

Thisdocumentcontainsparticularrequirementsforspecifictransformersortransformerapplications,whicharebasedontherequirementsofthegeneralEN50708-1-1:2020.

Thisdocumentshouldbeconsideredinconjunctionwiththerequirementsofthegeneralparts.

TheparticularrequirementsofthedifferentsubpartsofEN50708supplement,modifyorreplacecertainrequirementsofthegeneralpartsofEN50708-1and/orEN50708-1-Xbeingvalidatthetimeofpublicationofthisdocument.Theabsenceofreferencestotheexclusionofapartoraclauseofageneralpartmeansthatthecorrespondingclausesofthegeneralpartareapplicable(undatedreference).

Requirementsofother-XpartswithXgreaterthan1beingeventuallyrelevantforcasescoveredbythisdocumentalsoapply.Thisdocumentcouldthereforealsosupplement,modifyorreplacecertainoftheserequirementsvalidatthetimeofpublicationofthisdocument.

ThemainclausenumberingofeachpartfollowsthepatternandcorrespondingreferencesofEN50708-1-1:2020.Thenumbersfollowingtheparticularnumberofthisdocumentarethoseofthecorrespondingparts,orclausesoftheotherpartsoftheEN50708series,validatthetimeofpublicationofthisdocument,asindicatedinthenormativereferencesofthisdocument(datedreference).

Inthecasewhereneworamendedgeneralpartswithmodifiednumberingwerepublishedafterthesubpartwasissued,theclausenumbersreferringtoageneralpartinsubpartsmightnolongeralignwiththelatesteditionofthegeneralpart.Datedreferencesshouldbeobserved.

EN50708-2-1:2020(E)

5

1Scope

ThescopeofthisdocumentistodefinetheenergyperformanceofMediumPowerTransformersincompliancewithEN50708-1-1:2020.

2Normativereferences

Thefollowingdocumentsarereferredtointhetextinsuchawaythatsomeoralloftheircontentconstitutesrequirementsofthisdocument.Fordatedreferences,onlytheeditioncitedapplies.Forundatedreferences,thelatesteditionofthereferenceddocument(includinganyamendments)applies.

EN50708-1-1:2020,Powertransformers-AdditionalEuropeanrequirements:Part1-1:Commonpart-Generalrequirements

EN60076-1:2011,Powertransformers-Part1:General

EN60076-3:2013,Powertransformers-Part3:Insulationlevels,dielectrictestsandexternalclearancesinair

ENIEC60076-11:2018,Powertransformers-Part11:Dry-typetransformers

3Termsanddefinitions

Forthepurposesofthisdocument,thetermsanddefinitionsgiveninEN50708-1-1:2020apply.

ISOandIECmaintainterminologicaldatabasesforuseinstandardizationatthefollowingaddresses:

一IECElectropedia:availableat

/

一ISOOnlinebrowsingplatform:availableat

/obp

4Serviceconditions

SeeEN60076-1:2011.

5Ratingandgeneralrequirements

5.1General

5.1.1HighestvoltagesforequipmentforwindingwithUm>1,1kV

InsulationlevelsanddielectrictestshallbeinaccordancewiththerequirementsofEN60076-3:2013

andfordrytypetransformersinaccordancewithENIEC60076-11:2018.

ThevaluesofthehighestvoltageUmforequipmentare:

3,6kV-7,2kV-12kV-17,5KV-24kV-36kV

NOTENationalpracticesmightrequiretheuseofhighestvoltagesforequipmentupto(butnotincluding)

52kV,whentheratedvoltageislessthan36kV(suchasUm=38,5kVorUm=40,5kV).

5.1.2RatedvoltageforwindingwithUm≤1,1kV

ForUm≤1,1kV,thepreferredratedvoltagevalueshallbechoseninthehereunderlist:400V-410V-415V-420V-433V-690V

Thisdocumentmaybeappliedeitherasawholeorinpart,totransformerswithratedlowvoltagesbelow400Vandabove690V.

EN50708-2-1:2020(E)

6

Thevaluesforshortdurationpowerfrequencywithstandand/orforthelightningimpulsewithstandtestbetweenwindingsandearthneedtobestatedbythepurchaser.

5.1.3Tapping

ForDETC(De-energizedtapchanger),thepreferredtappingrangesshallbe±2,5%with3tappositionsand±2×2,5%with5tappositions.Onspecialrequest±4×2,5%with9tappositionscanbeprovided.Tappingrangesgreaterthan±10%orwithmorethan9tappositionsareunusualandsubjecttospecificagreement.

TappingrangesoutsidetheabovedefinitionsforDETCoranyrangesforOLTC(Onloadtapchanger)shallbespecifiedbyagreementbetweenmanufacturerandpurchaser.

Theleveloflossesofthisstandardshallbecompliantwhatevertherangesandmethodsoftapping.NOTEOLTCmeansalsotransformersequippedwithtappingconnectionssuitableforoperationwhiletransformerisenergisedoronloadforvoltageadaptationpurposes.

5.1.4Connectiondesignationsforthreephasetransformers

Preferredconnectiondesignations(IEV[421-10-09])shallbeinaccordancewithclocknotation5or11withDyn,unlessotherwiseagreedbetweenmanufacturerandpurchaser.

5.2EnergyPerformance

5.2.1General

Introduction

Thetablesbelowindicatethemaximumleveloflossesforno-loadlossesandforloadlossesforTIER1andTIER2.

TIER1hasbeenappliedsince1July2015forthevaluesoflossesfollowingCommissionRegulation(EU)No548/2014of21May2014anditsamendmentNo2019/1783of1October2019.

TIER2shallbeappliedfrom1July2021forthevaluesoflossesfollowingCommissionRegulation(EU)No548/2014of21May2014anditsamendmentNo2019/1783of1October2019.

Table1and2defineloadlossesandno-loadlossesforonewindingwithUm≤24kVandtheotheronewithUm≤3,6kV.Additionalcorrectionsaredefinedforhighestvoltage,dualvoltageorspecialonloadtapping,giveninTable3,4,5andotherclauses.CorrectionsfactorsinTable3,4,5arecumulative.

Duringfactoryacceptancetests,themeasuredvaluesofno-loadandloadlossesshallnotexceedtherespectivemaximumvaluesdeterminedwithTable1and2and6andcorrectedbycorrectionsfactorasstatedabove.

ThereferenceconditionsdefinedinEN50708-1-1:2020applies.

Othervaluesofshort-circuitimpedancecanbespecifiedbythepurchaserforparticularsystemserviceconditions,e.g.inthecaseofparalleloperationsinalltablesofthisclause.

ThesoundpowerlevelsaregiveninTables1and2.TransformerscanberequestedorofferedwithsoundpowerlevelLwAotherthanthelistedvalues.

UnlessotherwiseagreedbetweenmanufacturerandpurchaserthesoundpowerlevelLwAgivenin

Tables1and2areconsideredfornoloadcondition.

NOTELosslevelsandcorrectionfactorsdefinedin

an

d

refertotwowindingmediumpower

transformers.Losslevelsforthreewindingsmediumpowertransformersarenotdefinedduetolackofdataatthetimeofthepublicationofthisstandard.

EXAMPLEcumulativecorrections:

IncaseoftransformershavingprimaryhighestvoltageforequipmentUm=36kVandsecondaryhighestvoltageforequipmentUm≤3,6KVallowing10%onPkand15%onP⁰accordingtoTable3,andhavingdualvoltageononewindingallowing10%onPkand15%onP0accordingtoTable4.

EN50708-2-1:2020(E)

7

ThetotalcorrectionsonPkis21%(1,1x1,1-1)andP0is32,25%(1,15x1,15-1)

Loadlossesandno-loadlossesforonewindingwithUm≤24kVandtheotheronewithUm≤3,6kV

ThefollowingtablesaredefinedforstepdownorstepuptransformerswithonewindingwithUm≤24kVandtheotheronewithUm≤3,6kV.Table1isforliquidimmersedtransformersandTable2fordry-typetransformers.

Table1—Losses,shortcircuitimpedanceandsoundpowerlevelforliquidimmersed

transformers

Ratedpower

TIER1

Pk

TIER1

Po

TIER2

Pk

TIER2

Po

LwA

Short-circuitImpedance

kVA

w

W

W

W

dB(A)

%

≤25

900

70

600

63

37

4

50

1100

90

750

81

39

4

100

1750

145

1250

130

41

4

160

2350

210

1750

189

44

4

250

3250

300

2350

270

47

4

315

3900

360

2800

324

49

4

400

4600

430

3250

387

50

4

500

5500

510

3900

459

51

4

630

6500

600

4600

540

52

4or6

800

8400

650

6000

585

53

6

1000

10500

770

7600

693

55

6

1250

11000

950

9500

855

56

6

1600

14000

1200

12000

1080

58

6

2000

18000

1450

15000

1305

60

6

2500

22000

1750

18500

1575

63

6

3150

27500

2200

23000

1980

64

6

Table2—Losses,shortcircuitimpedanceandsoundpowerlevelsfordry-typetransformers

Ratedpower

TIER1

Pk

TIER1

Po

TIER2

Pk

TIER2

Po

LwA

Short-circuitImpedance

kVA

W

W

W

W

dB(A)

%

≤50

1700

200

1500

180

49

6

100

2050

280

1800

252

51

6

160

2900

400

2600

360

54

6

250

3800

520

3400

468

57

6

400

5500

750

4500

675

60

6

630

7600

1100

7100

990

62

6

800

8000

1300

8000

1170

64

6

1000

9000

1550

9000

1395

65

6

1250

11000

1800

11000

1620

67

6

1600

13000

2200

13000

1980

68

6

2000

16000

2600

16000

2340

70

6

2500

19000

3100

19000

2790

71

6

3150

22000

3800

22000

3420

74

6

EN50708-2-1:2020(E)

8

Loadlossandno-loadlossincaseofotherhighestvoltage

TheleveloflossesgiveninTable1andinTable2shallbeweightedbythecorrectionfactorsgiveninTable3below,inordertotakecareofvariationsrelatedtothehighestvoltageforequipmentvalues.

Table3—Correctionsofthelossesforhighestvoltage

Specialcombinationofvoltagesinonewinding

Loadlosses

(Pk)

No-loadlosses

(Po)

Forbothliquidimmersed(Table1)anddrytype(Table2)

PrimaryhighestvoltageforequipmentUm≤24KV

SecondaryhighestvoltageforequipmentUm>3,6kV

Nocorrection

Nocorrection

Forliquidimmersed(Table1)

PrimaryhighestvoltageforequipmentUm=36kV

SecondaryhighestvoltageforequipmentUm≤3,6kV

10%

15%

PrimaryhighestvoltageforequipmentUm=36kV

SecondaryhighestvoltageforequipmentUm>3,6kV

10%

15%

Fordrytype(Table2)

PrimaryhighestvoltageforequipmentUm=36kV

SecondaryhighestvoltageforequipmentUm≤3,6kV

10%

15%

PrimaryhighestvoltageforequipmentUm=36kV

SecondaryhighestvoltageforequipmentUm>3,6KV

15%

20%

Loadlossandno-loadlossincaseofdualvoltage

Table4belowgivescorrectionfactorstobeappliedtotheloadandno-loadlossesindicatedinTables1,2and6formediumpowertransformerswithdualvoltageinoneorbothwindingsdifferingmorethan10%.

ThelossesshallbecalculatedonthebaseofthevoltageofthewindingspecifiedinthesecondcolumnofTable4andcanbeincreasedwiththecorrectionfactorsgiveninthelast2columnsofTable4.Inanycase,whateverthecombinationsofwindingvoltages,thelossescannotexceedthevaluesgiveninTables1,2and6correctedbythefactorsinTable4.

EN50708-2-1:2020(E)

9

Table4—Correctionsofthelossesfordualvoltage

Typeofdualvoltage

Referencevoltage

fortheapplicationofcorrectionfactors

Loadlosses

(Pk)

No-load

losses

(Po)

Dualvoltageononewindingwithreducedpoweroutputonthelowerlow-voltagewinding

AND

maximumavailablepoweronthe

lowervoltageofthelow-voltagewindinglimitedto0,85oftheratedpowerassignedtothelow-voltagewindingatitshighervoltage.

Lossesshallbe

calculatedbasedonthehighervoltageofthelow-voltage

winding

Nocorrection

Nocorrection

Dualvoltageononewindingwithreducedpoweroutputonthelowerhigh-voltagewinding

AND

maximumavailablepoweronthe

lowervoltageofthehigh-voltagewindinglimitedto0,85oftheratedpowerassignedtothehigh-voltagewindingatitshighervoltage.

Lossesshallbe

calculatedbasedonthehighervoltageof

thehigh-voltagewinding

Nocorrection

Nocorrection

DualvoltageononewindingAND

fullratedpoweravailableonbothwindings,i.e.thefullnominalpowerisavailableregardlessofthecombinationofvoltages.

Thelossesshallbecalculatedbasedonthehighervoltageofthedualvoltage

winding

10%

15%

Dualvoltageonbothwindings

AND

ratedpoweravailableonallcombinationsofwindings,i.e.bothvoltagesononewindingarefullyratedincombinationwithoneofthevoltagesontheotherwinding

Thelossesshallbecalculatedbasedonthehighervoltagesofbothdualvoltage

windings

20%

20%

Incaseoftransformerswithtwoidenticallowvoltagewindingsand/orhighvoltagewindingsinparallelconnectiondesignedwithhalfofratedpowereach,dualvoltagecorrectionfactorsgiveninTable4shouldbeapplied.

NOTEIncaseoftransformerswithdualhighvoltagewinding,theratedpowerconsideredisonthehighestratedvoltagewinding.

5.2.2Transformerswithspecialrequirements

Ratedpowernotincludedinthelist

Fortransformerhavingaratedpowerdifferentfromthevaluesgiveninthetables,alinearinterpolationshallbedone.

Transformersequippedforvoltageregulationwhileenergised

Whentransformersareequippedwithtappingconnectionssuitableforoperationwhiletransformerisenergisedoronloadforvoltageadaptationpurposes,thelevelofloadlossandno-loadlossofthelistofthisstandardshallbeincreased.

EN50708-2-1:2020(E)

10

Table5—Correctionoflossesfortransformersequippedforvoltageregulation

Pk

Po

TIER1

5%

20%

TIER2

Nocorrection

10%

Suchcorrectionsareapplicableirrespectivelyofthetechnologyusedtoperformthevoltageadaptation.

Thelossesofthetransformersarethosemeasuredduringthetestwhateverthekindoftransformers,includedalldevicestomanagetheAVRinsidethetransformers.

ForatransformerhavinganinsulationlevelaccordingtoTable3andhavingtappingconnectionssuitableforoperationwhilethetransformerisenergizedoronloadforvoltageadaptationpurposesbothcorrectionsshallbetakenintoaccount.

NOTEAVR:AutomaticVoltageRegulation:toautomaticallycontroltheinputoroutputvoltageofthetransformerforon-loadvoltageregulationpurposes.

Liquidimmersedthreephasepolemountedtransformers

Fortheone-to-onereplacementofexistingmediumpowerpole-mountedtransformerstheapplicablemaximumlevelsofloadandno-loadlossesarenottheonesinTables1and2butthoseinTable6below.MaximumallowablelossesforkVAratingsotherthanthoseexplicitlymentionedinTable6shallbeobtainedbylinearinterpolationorextrapolation.ThecorrectionfactorsforspecialcombinationsofwindingvoltagesindicatedinTables3and4arealsoapplicable.

Fortheone-to-onereplacementofexistingmediumpowerpole-mountedtransformers,themanufacturer,importerorauthorizedrepresentativeshallincludeinthetechnicaldocumentationofthetransformerthefollowinginformation:

一theaddressandcontactdetailsofthecommissionerofthereplacementtransformer;

一thestationwherethereplacementtransformeristobeinstalled.Thisshallbeunequivocallyidentifiedeitherbyaspecificlocationoraspecificinstallationtype(e.g.technicaldescriptionofthepole).

Intheabovecases,themanufacturer,importerorauthorizedrepresentativeshallnotifythecompetentnationalmarketsurveillanceauthorities.

Withregardstotheinstallationofnewpole-mountedtransformers,itistherequirementsinTables1and2,inconjunctionwithTables3and4wherejustified,whichareapplicable.

Table6—Maximumloadandno-loadlossesformediumpowerimmersedpolemounted

transformersforonetoonereplacement

Ratedpower

TIER1

Pk

TIER1

Po

TIER2

Pk

TIER2

Po

kVA

W

W

W

W

25

900

70

725

70

50

1100

90

875

90

100

1750

145

1475

145

160

3102

300

3102

270

200

2750

356

2333

310

250

3250

425

2750

360

315

3900

520

3250

440

400

4750

645

3905

545

EN50708-2-1:2020(E)

11

6Ratingplate

TheadditionalrequirementsforratingplatearegiveninEN50708-1-1:2020.

Theone-to-onereplacementofexistingmediumpowerpole-mountedtransformersshallbewrittenontheratingplatebythewords“1/1replacement”

7Tolerancesduringfactoryacceptancetests

TheadditionalrequirementsfortolerancesaregiveninEN50708-1-1:2020.

8Tests

TheadditionalrequirementsfortestsaregiveninEN50708-1-1:2020orinrelevantparts.

9Accessoriesandfittings

Listofaccessoriesandfittingsareunderdevelopmentinrelevantparts.

10Capitalizationlosses

ThecapitalizationshouldbeappliedtofixedlossesbychoosingtheadequateratedpowerorbyspecifyinglowerlossesthanthemaximumvaluesgivenintheClause5.

11Transformersoverhaul

TheadditionalrequirementsfortransformersoverhaularegiveninEN50708-1-1:2020.

EN50708-2-1:2020(E)

12

AnnexZZ

(informative)

RelationshipbetweenthisEuropeanStandardandtheecodesign

requirementsofCommissionRegulation(EU)No548/2014of21

May2014anditsamendmentNo2019/1783of1October2019on

implementingDirective2009/125/ECoftheEuropeanParliament

andoftheCouncilwithregardtosmall,mediumandlargepower

transformersaimedtobecovered

ThisEuropeanStandardhasbeenpreparedunderaCommission'sstandardizationrequestM/495toprovideonevoluntarymeansofconformingtotheecodesignrequirementsofCommissionRegulation(EU)No548/2014of21May2014anditsamendmentNo2019/1783of1October2019onimplementingDirective2009/125/ECoftheEuropeanParliamentandoftheCouncilwithregardtoecodesignrequirementsforsmall,mediumandlargepowertransformers.

OncethisstandardiscitedintheOfficialJournaloftheEuropeanUnionunderthatRegulation,compliancewiththenormativeclausesofthisstandardgiveninTableZZ.1confers,withinthelimitsofthescopeofthisstandard,apresumptionofconformitywiththecorrespondingecodesignrequirementsofthatRegulationandassociatedEFTARegulations.

TableZZ.1—CorrespondencebetweenthisEuropeanStandardandCommissionRegulation

(EU)No548/2014of21May2014anditsamendmentNo2019/1783of1October2019

implementingDirective2009/125/ECoftheEuropeanParliamentandoftheCouncilwith

regardtoecodesignrequirementsforsmall,mediumandlargepowertransformersand

Commission'sstandardizationrequestM/495

Ecodesignrequirementsof

CommissionRegulation(EU)No

548/2014of21May2014andits

amendmentNo2019/1783of

1October2019

Clause(s)/subclause(s)ofthisEN

Remarks

Annexl

Requirementsforthree-phasemediumpowertransformerswith

ratedpower≤3150KVA.

Table1.3a

Maximumloadandno-loadlosses(inW)forthree-phaseliquid-immersedmediumpowertransformerswithonewindingwithUm≤24kVandtheotherwithUm≤3,6kV

Subclause

Table1reportsthevaluesTIER1Po,i.e.themaximumvaluesof

no-loadlossesthatareapplicablefrom1July2015(Tier1).

From1July2021(Tier2),therequirementisTIER2Po.

Table1reportsthevaluesTIER1Pk,whicharethemaximumloadlossesapplicablefrom1July2015(Tier1).

From1July2021(Tier2),therequirementisTIER2Pk

EN50708-2-1:2020(E)

13

Ecodesignrequirementsof

CommissionRegulation(EU)No

548/2014of21May2014andits

amendmentNo2019/1783of

1October2019

Clause(s)/subclause(s)ofthisEN

Remarks

Annexl

Requirementsforthree-phasemediumpowertransformerswith

ratedpower≤3150KVA.

Table1.2

Maximumloadandno-loadlosses(inW)forthree-phasedry-typemediumpowertransformerswithonewindingwithUm≤24kVandtheotherwithUm≤3,6kV

Subclause

Table2reportsthevaluesTIER1Po,i.e.thema