1. Kvalité från början till slut 2. Energieffektivare transformatorer

Bo Silversten bo.silversten@se.abb.com www.abb.se/transformatorer 1. Kvalité från början till slut 2. Energieffektivare transformatorer Slide 1

Transformatorer i varje fördelning Hjärtat i elnätet.. Slide 2

Resultatet av en kortslutning Slide 3

Hur utvärderar ni era transformator-upphandlingar? Förutom själva priset? Förluster, bortfall av inkomster? Värdera förlusterna ur ett livslångt perspektiv (TCO), från ett ecodesign-perspektiv (2015, 2021..?) Elpris-ökning över livslängden Hur värderas stillestånd och avbrott Kvalité, tillgänglighet och service? (IEC 60076 + Cigré) Verifiera transformatorns: Kortslutningstålighet IEC60076-5 (KEMA) Termiska tålighet IEC60076-2 Elektriska tålighet IEC60076-3 Verifiera detta genom att ställa krav i förfrågan (Cigré 528) Genomför en Design Review hos leverantören (Cigré 529) Utvärdera leverantörens fabrik, tillverkning och eftermarknadsservice (Cigré 530) Säkerhet? Hur värderas drift-, person- och miljösäkerhet mot brand, för fastigheter och andra egendomar etc. Inställelsetid och kompetens hos serviceföretag OPEX CAPEX Slide 4

Avbrott Stilleståndskostnader Reparationer Kvalitetsproblem Slide 5

Ingen vill uppleva detta! Avbrott Stilleståndskostnader Reparationer 1. Kortslutningspåkänningar under flera år i drift men transformatorn kan fortsätta att fungera 2. Lindningarna påverkas men transformatorn kan fortsätta att fungera 3. Nästa kortslutning förstör transformatorn explosion och brand 4. Havererad transformator och totalt avbrott 1. Lindning utsatt för kortslutning 2. Buckling 3. Brand och explosion 4. Havererad transformator En transformator designad enligt IEC 60076-5 ska vara kortslutningssäker. Det finns ett stort antal transformatorer som aldrig har blivit testade mot kortslutningskrafter eller som har blivit tekniskt verifierade av köparen. Slide 6

Cigré Guideline 528 - för bra specifikationer Kortslutningsstatistik från KEMA, Holland ABB Alla testade Slide 7 Många transformatorer är inte kortslutningssäkra KEMA = 28 % testfel ABB = 11 % testfel KEMA ABB = 35-40 % testfel

Transformatorer Isolationsmaterial Isolations-systemet = papper och olja i samarbete Slide 8

Termisk hållfasthet ej säkerställd eller verifierad! Hot spots, överhettning, nedbrytning av isolation Slide 9

Upphandling av krafttransformatorer Cigrés rekommendationer för hög kvalité 1. Använd alltid auditerade tillverkare [Cigré 530] 2. Specifikationer baserade på funktionskrav [Cigré 528] Specificera funktioner, men inte lösningar Energieffektivitet genom förlustvärdering värderad över livslängden 3. Verifiera de viktigaste transformatorkriterna [Cigré 529] Mekaniskt Tester enligt IEC 60076-5 och Design Review [Cigré 529] Termiskt Tester enligt IEC 60076-3 och Design Review [Cigré 529] Dielektriskt Tester enligt IEC 60076-2 Edit.3 Slide 10 Kvalitetsaspekterna blir än viktigare hur formuleras dessa i de standards vi använder?

Cigré guidelines for power transformers Slide 11

Cigré Guidelines - 2013 Specifikationer 528, Design Review 529, Utvärdering 530 Slide 12

Cigré Guideline 528 - för bra specifikationer Guide för upphandlingsprocessen Innehåller specifikationen dina krav? Har tillverkaren förmågan? Är anbudskraven uppfyllda? Verifiera att designen uppfyller kraven! Slide 13

Cigré Guideline 528 för bra specifikationer Hur skrivs en bra specifikation? Guide för att göra en specifikation Nyckelordet för att få den transformator som man vill ha är kommunikation. Specifikationen är grunden till den tekniska kommunikationen. Belyser viktiga delar i specifikationen Förklarar syfte och betydelse med specifikationen Refererar till IEC Specificera kvalitetsfaktorer istället för bara kostnader Specificera funktioner men inte lösningar Energieffektivitet genom korrekt förlustvärdering där MEPS är ett minimum Slide 14 Nödvändigt att se över specifikationer oftare

Cigré Guideline 528 - för bra specifikationer Specificera tekniska parametrar Inkludera Temperaturstegring Isolationsnivåer Överspänningar Ljudnivåer Förlustvärderingar m.m. Exkludera Magnetisering Strömtäthet Isolationsavstånd Marginalkrav m.m. Slide 15 Specificera funktioner, men lämna lösningarna till tillverkaren

Cigré Guideline 528 - för bra specifikationer Tydliggör dina utvärderingskriterier Vilka kriterier är viktiga för Dig? Pris..? Förluster..? Referenser..? Cigré 528 Appendix A: Loss evaluation, penalties/ bonuses and rejection Tillverkarens kapacitet..? Teknisk kompetens..? Kvalitet..? Projektgenomförande..? Service, eftermarknad, inställelsetid..? Med flera Slide 16 Utvärderingskriterier en del av specifikationen

Short-circuit strength of Power Transformers IEC 60076-5 Slide 17

Cigré Guideline 528 - för bra specifikationer Kortslutningsstatistik från KEMA, Holland ABB Alla testade Slide 18 Många transformatorer är inte kortslutningssäkra KEMA = 28 % testfel ABB = 11 % testfel KEMA ABB = 35-40 % testfel

Kortslutningskrafter Visste du att Kortslutningsströmmar skapar mekaniska krafter i lindningarna Kortslutningsströmmar är 10-20 gånger nominell ström Krafterna i lindningarna är 100-400 gånger större jämfört med normal driftförhållanden Lindningarna är en mycket känslig del för mekanisk stress Kortslutningståligheten är nyckeln för en pålitlig drift Slide 19

Kortslutningskrafter Elektromagnetisk kraft i en ledare (ström-kraft-flöde) F I 2 Slide 20

Kortslutningskrafter Elektromagnetiska krafter i en lindning (2-lindnings konfig.) Active part Core Inner winding Outer winding Slide 21

Kortslutningskrafter Dynamiska effekter av en kortslutning Dynamic effects are taken into account by either,..dynamic factors, or..dynamic calculation Slide 22

Kortslutningskrafter Ackumulerade axiella elektromagnetiska krafter utefter en lindning Ändkrafter pga. axiell förskjutning, trycker lindningen mot toppen Max. ackumulerad elektromagnetisk kraft Slide 23

Kortslutningskrafter Axiella krafter ökar p.g.a. obalans (axiell förskjutning) Innerlindning Ytterlindning F axial F axial Slide 24 Netto-krafterna (uppåt/nedåt) orsakar stress i ändisolationen!

Kortslutningskrafter Exempel 100 MVA transformator Peak = 70 ka Current Force Current 2 Force F I 2 Time Krafter i en bilkrasch (100 km/h) Peak = 2300 kn Time I en transformator är kraften dubbelt så stor (jmf med bilkraschen ovan), och lindningen måste klara ett flertal kortslutningspåkänningar under en kortslutning Slide 25 Dimensionering av kortslutningståligheten kan vara utmanande!

Kortslutningskrafter Dynamiska effekten av en kortslutning, specifikt i IEC 60076 Dynamisk last Statisk last Slide 26 Dynamiska (pulserande) krafter skapar mycket mera stress än statiska krafter

Kortslutningsfel Buckling Radial forces: Buckling Spiraling Stretching of conductors Axial forces: Tilting of conductors Telescoping Bending of conductors Collapse of end insulation Slide 27

Kortslutningsfel Buckling IEC 60076-5: Limit for compressive stress (MPa) Regular strands, non-bonded CTCs Resin-bonded strands, CTCs 0.35 σ 0.2 0.6 σ 0.2 CTC cable Glue Slide 28 Ökad säkerhetsfaktor mot buckling, med epoxyinbunden CTC ledare

Kortslutningsfel Spiraling Radial forces: Buckling Spiraling Stretching of conductors Axial forces: Tilting of conductors Telescoping Bending of conductors Collapse of end insulation Slide 29

Kortslutningsfel Spiraling IEC 60076-5: Limit for thrust force acting on low-voltage winding exits leads (kn) N/A Slide 30

Kortslutningsfel Tilting of conductors Radial forces: Buckling Spiraling Stretching of conductors Axial forces: Tilting of conductors Telescoping Bending of conductors Collapse of end insulation Slide 31

Kortslutningsfel Tilting of conductors IEC 60076-5: Limit for actual axial compressive force (kn) 0.8 F tilting,critical Slide 32

Kortslutningsfel Telescoping Radial forces: Buckling Spiraling Stretching of conductors Axial forces: Tilting of conductors Telescoping Bending of conductors Collapse of end insulation Slide 33

Kortslutningsfel Bending of conductors Radial forces: Spiraling Buckling Stretching of conductors Axial forces: Tilting of conductors Telescoping Bending of conductors Collapse of end insulation Slide 34

Kortslutningsfel Bending of conductors IEC 60076-5: Limit for bending stress on conductors (MPa) Axial bending in the span between radial spacers Radial bending in the span between axial sticks or spacers 0.9 σ 0.2 0.9 σ 0.2 Slide 35 Lindningarna är dimensionerade att vara självbärande, för att undvika fri buckling

Kortslutningsfel Collapse of end insulation Radial forces: Buckling Collapse of end insulation Spiraling Stretching of conductors Axial forces: Tilting of conductors Telescoping Bending of conductors Collapse of end insulation Slide 36

Kortslutningsfel Collapse of end insulation Stacked type - Horizontally laminated pressboard Wound type - Vertically laminated pressboard IEC 60076-5: Limit for compressive stress in end insulation (MPa) Stacked type 80 Wound type 40 Slide 37

Cigré Guideline 528 - för bra specifikationer IEC 60076-5 (edit 3, 2006) Short circuit strength Så här står det i IEC Ability to withstand the dynamic effects of short circuit 1 Scope This part of IEC 60076 identifies the requirements for power transformers to sustain without damage the effects of overcurrent's originated by external short circuits. It describes the calculation procedures used to demonstrate the thermal ability of a power transformer to withstand such overcurrent's and both the special test and the theoretical evaluation method used to demonstrate the ability to withstand the relevant dynamic effects. The requirements apply to transformers as defined in the scope of IEC 60076-1. 4.2.1 General If required by the purchaser, the ability to withstand the dynamic effects of short circuit shall be demonstrated either by tests, or.. by calculation and design and manufacture considerations. The choice of method of demonstration to be used shall be subject to agreement between the purchaser and the manufacturer prior to placing the order. Slide 38 Hur kan detta verifieras?

Cigré Guideline 528 - för bra specifikationer IEC 60076-5 (edit 3, 2006) Short circuit strength Så här står det i IEC Theoretical evaluation of the ability to withstand the dynamic effects of short circuit (Annex A) Annex A gives guidelines for the theoretical evaluation of the ability of a power transformer to withstand the dynamic effects of short circuit, based on calculation and consideration of the design characteristics and manufacturing practices. The theoretical evaluation of the ability of a power transformer to withstand the dynamic effects of short circuit consists of a design review covering the main mechanical strength aspects of the transformer. A.3 Guidelines for conducting the design review Slide 39 Hur kan detta verifieras?

Design review according to IEC 60076-5 Calculated and allowed forces in windings Stretching of conductors Free buckling Forced buckling Bending of conductors Spiraling Crushing of turnto-turn insulation Slide 40

Design review according to IEC 60076-5 Calculated and allowed forces in windings Tilting of conductors Crushing of end insulation Crushing of turn-to-turn insulation Collapse of end support Collapse of press ring Slide 41

Kortslutningshållfasthet Förslag på text Förslag på text Short circuit withstand capability Short circuit withstand capability shall be verified at Design Review according to Cigré TB 529. Special attention shall be taken to production tolerances in the short circuit design. The short circuit design should also comply with IEC 60076-5, Annex A. The calendar time for this Design Review will be decided in the Post Contract Design Review. The tender shall include, as an option, full short circuit test on one transformer. Price for test and adjusted delivery schedule due to test shall be quoted in this option. After the Design Review, the owner (customer) will decide if the option of short-circuit test will be used. Slide 42 Specificera Annex A för att undvika misstolkning av IEC

Kortslutningshållfasthet Summering Kortslutningskrafterna i lindningar är 100-400 gånger större än under normal drift IEC kräver att krafttransformatorer vara designade för att klara av kortslutningar Kortslutningskrafter och peak-faktor måste specificeras för design av korrekt felström Kortslutningskrafter delas in i axiella och radiella krafter Axiell obalans i lindningar skapar större axiella krafter Dynamiska krafter kan beräknas genom dynamiska modeller eller dynamiska faktorer Risken för kortslutningsfel kan utvärderas i en Design Review enligt IEC 60076-5 Ca 28% av alla kortslutningstestade transformatorer fallerar hos KEMA s testlaboratorier i Holland Slide 43

Kortslutningshållfasthet Rekommendation Design review enligt IEC 60076-5 (Cigré 529), kan teoretiskt försäkra att transformatorn är kortslutningssäker Kortslutningsprov kan praktiskt försäkra att transformatorn är kortslutningssäker Slide 44

Thermal strength of Power Transformers IEC 60076-2 Slide 45

Cigré Guideline 528 - för bra specifikationer IEC 60076-2 Termisk design Använd relevant Hot-spot-faktor Hot-spot faktor H Så här står det i IEC Slide 46 Relevant hot-spot faktor ska alltid användas i FAT, inte bara 1.3 från IEC standarden

Cigré Guideline 528 - för bra specifikationer Termisk design Oljestyrd kylning med blockstyrning Oljekylningsguide Blockera oljan vertikalt Tvinga oljan gå horisontalt Slide 47 Viktigt visa hur oljestyrningen är mest effektiv

Cigré Guideline 528 - för bra specifikationer Termisk design Oljestyrd kylning med blockstyrning Cooling types ONAN = Oil Natural Air Natural ODAF = Oil Directed Air Forced ONAF = Oil Natural Air Forced ODWF = Oil Directed Water Forced OFAF = Oil Forced Air Forced Slide 48 OFWF = Oil Forced Water Forced

Temperature, C Cigré Guideline 528 - för bra specifikationer Termisk design Hot-spot stor inverkan på åldringen 114 Hot-spot temperatures, C 112 110 108 5 K difference 106 104 102 Oil guide 66 Oil guide 66 Oil guide 66 68 Oil guide 68 Oil guide 70 100 98 96 94 60 62 64 66 68 70 72 74 76 78 80 Disc number Slide 49 Vi rekommenderar mätning av Hot-spot med optisk fiber

Cigré Guideline 528 - för bra specifikationer Termisk design Åldringshastighet Åldringshastigheten fördubblas var 6-8:e grad i hotspot-regionen Aktuella livslängden är beroende av många faktorer under driftperioden Slide 50 Åldringshastigheten fördubblas vid 6 graders ökning

Cigré Guideline 528 - för bra specifikationer IEC 60076-2 Termisk design i specifikationen förslag till text. Thermal capability, winding temperature rise incl. Hot Spots Förslag på text The transformers shall fulfill requirements in IEC 60076-2: Temperature rise for liquid-immersed transformers General: The thermal capability for Winding Hot-spot shall be verified both at Design Review and after the Temperature rise test. Time for this will be decided in project kick-off meeting. If not otherwise stated all transformers, even multi winding transformers, shall be capable of continuous operation with rated current in all windings without exceeding the allowable standardized temperature rises, note both mean winding temperature rise and hot spot rise. The tender shall include, as an option, direct temperature measurements by fiber-optics in the main windings upper regions. Price for test and adjusted delivery schedule due to test shall be quoted in this option. Temperature rise: Recorded and calculated temperatures and mean winding and hot spot temperature rises shall be presented with one decimal place in the test report. In the final summary integers shall be used. Method of calculating the hot spot temperature from the heat run test shall be described when no fiber optic transmitters are used. Winding thermometers shall in connection with the temperature rise test be calibrated to show the true winding hot spot temperature, i.e. calibrated by means of the true hot spot factor. All necessary parameter settings and description of the hot spot factor calculation methodology shall be presented in the test report. Slide 51 Del av specifikationen

Design review of Power transformers Cigré guide line 529 Slide 52

Cigré Guideline 529 - för bra Design Review Varför en Design Review? Se till följande: Applikation Kontraktsförståelse Tolkning av använda standards Tolkning av specifikationen Övriga krav Säkra kvalitén Verifiera designen enligt kravspecifikationen Identifiera risker (ny teknologi, nya lösningar ) Slide 53 Del av specifikationen

Cigré Guideline 529 - för bra Design Review Säkerställer kvalitén En Design Review enligt Cigré 529, ska genomföras med avsikt att göra en grundlig kontroll av den beställda transformatorn, och att ge köparen en tydlig förståelse för transformatorns konstruktion, tillverkning och provning. Design Review ska hållas så snart konstruktionen har frysts. Slide 54 Del av specifikationen

Cigré Guideline 529 - för bra Design Review Transformatordesign Kärnan Kärnans hot spot Kärnplåtskvalité Märke, typ, kvalité Kärnplåtsisolation Överlappning, design, toleranser Max flödestäthet Kärn-kylning Kärn-infästning Magnetisk flödeskontroll, skärmning Etc.. Shunt Reactor core Slide 55 Tillverkaren ska förklara hur kärnan kommer att uppträda inom dessa parametrar

Cigré Guideline 529 - för bra Design Review Transformatordesign Lindningarna Lindningstyp, dimensioner och detaljer Typ av ledare, kardeler, isolation Transponeringar Strömtäthet Axiella och radiella kanaler, toleranser Isolationssystem Läckfält, övertoner Omkopplings-disposition Virvelförluster Mekaniska krafter Lindningars termiska analyser Kartläggning av lindningens hot-spot temperaturer Lindningsdimensionering / pressning / behandling Slide 56 Tillverkaren ska förklara hur lindningarna kommer att uppträda inom dessa parametrar

Supplier capability assessment of Power transformers - Cigré guide lines 530 I linje med: LUF 2007:1092 Kvalificering och urvalsbedömning (11kap.) Slide 57

Cigré Guideline 530 bedömer fabrikens förmåga Syfte med bedömningen Certifiera hög kvalité på leverantörerna Effektivare anbudsprocesser Effektivare projektgenomförande Livslängdstänkande Ökad kvalité Du vet vad du köper Slide 58 Syftet med att prekvalificera en fabrik

Cigré Guideline 530 bedömer fabrikens förmåga Produktkvalitet, processkvalitet och servicekvalitet mm 9 Värderingsgrunder (i grunden ca 14 aspekter): Pris, förluster och Leveranstid.. 1. Fabrikens prestanda Prestanda, genomloppstid, OTD, kvalitets-störningar, FAT tester 2. Beräknings- och konstruktionsverktyg, IT-verktyg Beräknings- och konstruktionsregler, IT-programvara, konstruktionsverktyg 2D/3D, termisk nätverksmodell, dynamiska kortslutningskrafter 3. Inköpsprocessen Inköpsprocesser mer krav och uppföljningar, revision av underleverantörer, kontinuerliga förbättringar, kontroll av kärnplåtsleverantörer, avvikelser på kärnförluster, kopparledarens hårdhet 4. Tillverkningsmetoder och provning Kontrollkort, kontrollpunkter, renlighet, press av aktiv del och lindningar, torrhetskontroll, testnoggrannhet, kortslutningstester, test- och inspektionsplan 5. Teknologi-bakgrund Teknologibakgrund, R&D utveckling, processer och rapporter 6. Transport och installation Transportmanual, ansvarsförhållanden, transportkontrollkort, impact recorder 7. Garanti och Service efter leverans (under livslängden) Lokal serviceorganisation, reservdelar, tillgänglighet, inställelsetid, kommunikation... 8. Finansiella, kommersiella och legala aspekter 9. Hälsa och säkerhet Slide 59 Värderingsgrunder vid en upphandling

Cigré Guideline 530 bedömer fabrikens förmåga Checklista Slide 60

Evaluation criterias Utvärderingskriterier Evaluation criterias acc. to Cigré guide line 530 Evaluation criterias Yes No Excellent Good Poor Unacceptable Total 1 Load Losses and Load Temperature 0,75 15% 2 Short Circuit Strength and Mechanical Integrity Rules 0,94 20% 3 Design Methods and Tools 0,75 10% 4 Expert Technical Support 0,50 10% 5 Bushings and Load Tap Changers 0,63 10% 6 Core Steel 0,50 10% 7 Test Equipment 0,70 10% 8 After Sales Arrangement 1,00 10% 9 Health and Safety Management 0,75 5% Total summary evaluated: value importance 4 3 2 1 value per item 4 3 2 0 9 12 3 0 0 15 0 9 0 0 9 0 0 4 0 4 0 3 2 0 5 0 0 4 0 4 0 12 2 0 14 16 0 0 0 16 0 12 0 0 12 0,75 100% 32 42 14 0 88 Slide 61 0-60% 61-84% 85-100%

Evaluation criterias Utvärderingskriterier Fråga: 1. Load Losses and Load Temperature a) What thermal design calculation computer programs does the factory use? b) Have the thermal calculations been validated by fibre optic measurements? c) Are hot spot temperatures calculated for windings, core, internal clamping structures and the tank, at worst case operating conditions? Värdering: 1 = no computer design tools available, calculation based on previous test reports, 2 = local design tools, 3 = global corporate design tools, 4 = 3D computational fluid dynamics software 1 = no fibre optic experience, 2 = less than 5 years experience, 3 = experience between 5-20 years, 4 = more than 20 years experience 1 = no computer design tools available, calculation based on previous test reports, 2 = local design tools, 3 = global corporate design tools, 4 = 3D multiphysics software Value = summerar varje delavsnitt (1-9) Importance = viktighetsvärdering i % av totalt 100% Evaluation criterias acc. to Cigré guide line 530 Evaluation criterias Description to Evaluation criterias Yes No Excellent Good Poor Unacceptable Total value importance 4 3 2 1 value per item 1 Load Losses and Load Temperature 0,75 15% 1 = no computer design tools available, calculation based on previous test reports, 2 = local a What thermal design calculation computer programs does the factory use? 4 design tools, 3 = global corporate design tools, 4 = 3D computational fluid dynamics software 1 = no fibre optic experience, 2 = less than 5 years experience, 3 = experience between 5-20 b Have the thermal calculations been validated by fibre optic measurements? 3 years, 4 = more than 20 years experience Are hot spot temperatures calculated for windings, core, internal clamping structures and the 1 = no computer design tools available, calculation based on previous test reports, 2 = local c 2 tank, at worst case operating conditions? design tools, 3 = global corporate design tools, 4 = 3D multiphysics software 4 3 2 0 9 2 Short Circuit Strength and Mechanical Integrity Rules 0,94 20% Does the factory demonstrate short circuit withstand capability by design calculations in 1 = no computer design tools available, calculation based on previous test reports, 2 = local a 4 accordance with IEC 60076-5? design tools, 3 = global corporate design tools, 4 = FEM software 1 = no criterias available, 2 = IEC 60076-5 criteria applied, 3 = own criterias more demanding than b What criteria are used for axial and radial strengths of the windings? 4 IEC, 4 = all criterias applied are verified with tests 1 = no SC test references, 2 = only few corporate (not own factory) SC test references (<10pcs), 3 = several corporate (including own factory) SC test references (>10pcs), 4 = comprehensive list tests? 4 c Has the factory performed short circuit of successfull SC test references d If yes, what has been the experience? 3 1 = below 50% FPY, 2 = 50% - 75% FPY, 3 = 75% - 90% FPY, 4 = >90% FPY 3 12 0 0 15 3 Design Methods and Tools 0,75 10% 1 = no computer design tools available, calculation based on previous test reports, 2 = local a How does the factory optimise the transformer designs? 3 design tools, 3 = global corporate design tools, 4 = multivariable optimizer 1 = no computer design tools available, 2 = local transient tools, 3 = global corporate transient b Does the factory calculate dielectric stresses down to single turns? 3 tools, 4 = global transient tools compined with FEM analysis 1 = no computer design tools available, calculation based on previous test reports, 2 = local design tools, 3 = global corporate design tools (3D CAD only), 4 = 3D FEM & Magnetics & 3D CAD c Does the factory use 3-D design programs and 3-D CAD systems? 3 daily use 0 9 0 0 9 4 Expert Technical Support 0,50 10% 1 = no specialist available, 2 = limited local technical support available, 3 = local support a Are any technical specialists available to support the user? 2 available, 4 = global support available Where are the technical specialists based (at the factory, at another factory owned by the 1 = no specialist available, 2 = limited local technical support available, 3 = local support b 2 same Manufacturer)? available, 4 = global support available 0 0 4 0 4 5 Bushings and Load Tap Changers 0,63 10% 1 = no frame agreements or regular purchasing, 2 = frame agreements with single supplier, 3 = frame agreements with major suppliers, 4 = frame agreements with major suppliers including a Does the Manufacturer have an established relationship with the equipment suppliers? 3 also own manufacturing of components 1 = no quality audits performed, 2 = irregular audits performed. 3 = regular periodic audits b Does the Manufacturer perform a periodic quality audit of the suppliers? 2 performed, 4 = global corporate audit system in place 0 3 2 0 5 6 Core Steel 0,50 10% 1 = no agreements, spot purchasing only, 2 = agreement with 1 supplier & spot purchase, 3 = a Which sources of core steel are used by the Manufacturer? 2 agreements with several suppliers, 4 = partnership agreements with major suppliers b Does the Manufacturer check the core steel suppliers' loss certificates? 2 1 = no, 2 = random check only, 3 = statistical follow up, 4 = statistical follow up with feedback 4 0 0 0 4 7 Test Equipment 0,70 10% 1 = all SC tests performed at external test lab., 2 = Some SC tests are performed at own test lab., 3 = All SC tests are performed at own test lab., 4 = Own accredited test lab. Available for all SC a Where are short circuit tests typically performed? 3 tests 1 = no SC test references, 2 = only few SC test references (<10pcs), 3 = several SC test references b Is there a short circuit test reference list available? 3 (>10pcs), 4 = comprehensive list of successfull SC test references 1 = can not be performed at all, 2 = 3rd party lab used, results in few days, 3 = can be performed c Can the factory perform dissolved gas analysis (DGA) on-site or is it performed by 3rd party? 3 by factory, results in 1 day, 4 = can be performed by factory + on-line monitoring during test Can the factory perform routine tests in the field (capacitance, power factor, TTR, frequency 1 = can not be performed, 2 = some of routine tests can be performed (<50%), 3 = some of d 3 response analysis, etc? routine tests can be performed (>50%), 4 = all routine tests can be performed at site Does the factory have the capability to perform no-load, applied potential, induced, or e 2 1 = can not be performed, 2 = some of mentioned tests can be performed (<50%), 3 = some of impulse tests in the field? mentioned tests can be performed (>50%), 4 = all mentioned tests can be performed at site 0 12 2 0 14 8 After Sales Arrangement 1,00 10% 1 = can not be performed, 3rd party always needed, 2 = some of mentioned activities can be Can the Manufacturer offer support in terms of condition assessment, DGA sampling and a 4 performed (<50%), 3rd party needed, 3 = some of mentioned activities can be performed analysis, on site testing etc. (>50%), 3rd party needed, 4 = all mentioned activities can be performed at site by factory 1 = not at all, 2 = repair work for tank and external parts only, 3 = repair work for active part also, b Can the Manufacturer carry out transformer repairs? 4 4 = dedicated repair shop available for repair work 1 = not at all, 2 = for tank and external parts only, 3 = for active part only, 4 = dedicated repair c Is the Manufacturer prepared to do so? 4 shop global network available for repair work 1 = not at all, 2 = local service offering, 3 = global service network, only own service workshop, 4 d Can the Manufacturer offer any added value maintenance service products? 4 = global dedicated service network with several local workshops 16 0 0 0 16 9 Health and Safety Management 0,75 5% a Is the factory OSHAS 18000 certified? 3 1 = no, 2 = certification received less 2 years ago, 3 = certification in place, but no evidence of improments yet, 4 = certification in place more than 5 years, improvement evidence available b What is the factory health and safety policy? 3 1 = no policy & no certificate, 2 = certificate available but targets not defined, 3 = certificate available & targets set, 4 = certification available for many years and target to be a world class leader c Is the health and safety management system adequately documented? 3 1 = no, 2 = documentation work started for certification, 3 = documentation work done but no audited yet, 4 = audited and certified system d Is the factory management making good use of the health and safety management system 3 1 = not used, 2 = for own factory only not covering site works, 3 = factory system & 3rd party site used ain their site works? personnel with their own system, 4 = global system applied to own and 3rd party personnel 12 0 0 0 12 Total summary evaluated: 0,75 100% 32 42 14 0 88 Slide 62

Exempel på utvärdering Värdering idag: Pris ~70% Förluster ~30% Cigré 530...? Egna krav-kriterier...? Värdering av kvalité & energieffektivitet: Pris 20% Förluster 50% Cigré 530 25% Egna krav-kriterier 5% Slide 63

Summering Öka och verifiera kvalitén i upphandlingsprocessen Certifiera fabriker (prekvalificering) Öka kvalitén i Specifikationerna (Cigré 528) Verifiera kvalitén genom Design Review (Cigré 529) Använd fler objektiva Utvärderingskriterier (Cigré 530) Se kostnaden över Livslängden Högre förlustvärdering för en bättre miljö! Jämför äpplen med äpplen! Slide 64

Sammanfattning En bra investering börjar redan i förfrågningsunderlaget Cigré guidelines Upphandlingsprocessen Specificera funktioner TCO Inkludera Temperaturstegring Isolationsnivåer Överspänningar Ljudnivåer Förlustvärderingar m.m. Exkludera Magnetisering Strömtäthet Isolationsavstånd Marginalkrav m.m. Prisökning per år Förlustkostnader Elpris 28 % ej kortslutningssäkra Hot-spot Ny pd-standard Design review Utvärdera tillverkare Nyckelordet är Kvalité både i specifikationen, utvärdering och i verifieringen av transformator och fabrik Slide 65

Energy Efficient Transformers Sustainable transformers Slide 66

Energieffektivisering och förnybar energi EE kan bidra med 2/3 av nödvändig utsläppsminskning World energy-related CO 2 savings potential by policy measure under 450 Policy Scenario relative to New Policies Scenario Source: IEA, World Energy Outlook 2011 (www.iea.org ) 35,9 CO 2 emissions (Gt) New Policy Scenario 2020 2035 Efficiency 72% 44% Renewables 17% 21% Biofuels 2% 4% I EU är elnätsförlusterna från kraft- och distributionstransformatorer ca 100 TWh, ( 40 Mton emissioner CO 2 per år.) Juli 2016: 404,39 ppm Juli 2015: 401,31 ppm 450 Policy Scenario Nuclear 5% 9% CCS* 3% 22% *CCS=Carbon capture and storage Ökningstakten har gått från 1 ppm/år till ca 3 ppm/år. Dvs. om ca 15 år har vi 450 ppm CO 2 i atmosfären. 2009 2014 2020 2035 2015 Källa 2013: GCP - The Global Carbon Project Slide 67

Transformer Losses and Efficiency Power transformer are >99.5% efficient Background Origin of transformer losses Global climate discussion Driver for Energy efficiency Transformer optimiation process Loss evaluation Effect of high no-load loss evaluation Effect of high load loss evaluation Real case study (N1) Current R&D activity Summary Losses in the structural parts Stray losses Losses in the core Hysteresis losses Eddy losses Losses in joints Core loss Load loss Slide 68 Losses in the winding Ohmic losses Eddy losses

Ultra Efficient Transformer Motivations Stay ahead of regulation Background Origin of transformer losses Global climate discussion Driver for Energy efficiency Transformer optimiation process Loss evaluation Effect of high no-load loss evaluation Effect of high load loss evaluation Real case study (N1) Current R&D activity Summary EC directive No. 548/2014: Maximum allowed NLL (Tier 1, A 0 ). Ex. 2.5 MVA (3500W reduced to 1750W) Proposed EC directive 2021: Maximum allowed NLL (A 0-10%), Ex. 2.5 MVA (3500W reduced to 1575W) EN50588: 2.5MVA AAA 0 ratings 880W Globally 1800 TWh energy lost in electricity system out of which ~720 TWh energy lost as transformer losses Carbon intensity of global energy mix is 0.8 kg/kwh 40-50% (250 Megton) carbon emission can be reduced Energy efficient transformers 576 Megaton of CO 2 contributed by Transformer Globally 700 TWh of energy lost as transformer losses Global Economy value of losses is ~ 40-50 BUSD With global average price of electricity of 6-8 USD cent Fact: Global Market size for transformer is in the order of 35 BUSD Slide 69

Design optimization of power transformer Price + Cost of Losses = TCO Background Origin of transformer losses Global climate discussion Driver for Energy efficiency Transformer optimiation process Loss evaluation Effect of high no-load loss evaluation Effect of high load loss evaluation Real case study (N1) Current R&D activity Summary Risks: Thermal Acoustic Price Cost of losses Total Ownership Cost Transportation limits Spatial constraints Mechanics Lower value of losses = High loss design Masses of transformer parts (kg) Higher value of losses =Low loss design Slide 70

Capitalized Cost of Losses Present value of future losses Background Origin of transformer losses Global climate discussion Driver for Energy efficiency Transformer optimiation process Loss evaluation Effect of high no-load loss evaluation Effect of high load loss evaluation Real case study (N1) Current R&D activity Summary 600 500 400 300 200 100 Price, 0.06 /kwh Interest rate, 5% Cost of no-load loss ( ), every year Present value of cost of no-load losses ( ) 40 years of life time No increase in price, No CO 2 tax Yearly cost of no-load losses 8760*0.06=526 /kw 9,000 /kw (sum of present values of losses over 40 years) 0 1 6 11 16 21 26 31 36 Years Slide 71

Capitalized Cost of Losses Present value of future losses Background Origin of transformer losses Global climate discussion Driver for Energy efficiency Transformer optimiation process Loss evaluation Effect of high no-load loss evaluation Effect of high load loss evaluation Real case study (N1) Current R&D activity Summary 600 500 Price, 0.06 /kwh Interest rate, 5% Cost of no-load loss ( ), every year Yearly cost of no-load losses 8760*0.06=526 /kw Present value of cost of no-load losses ( ) 40 years of life time No increase in price, No CO 2 tax Price, 0.06 /kw Interest rate, 5% 1200 9,000 /kw 40 years of life time Cost of no-load loss ( ), every year 2% increase in price, or inflation Present value of cost of no-load losses ( ) 12,300 /kw 400 1000 Slide 72 300 200 100 0 1 6 11 16 21 26 31 36 Years 800 600 400 200 0 1 4 7 10 13 16 19 22 25 28 31 34 37 40 Years

Capitalized Cost of Losses No load loss evaluation ( /kw)* Background Origin of transformer losses Global climate discussion Driver for Energy efficiency Transformer optimiation process Loss evaluation Effect of high no-load loss evaluation Effect of high load loss evaluation Real case study (N1) Current R&D activity Summary Energy price 0.06 /kwh Interest rate (%) Increase in energy price (%) 0 0.5 1.0 1.5 2.0 3 12,100 13,200 14,400 15,800 17,300 4 10,400 11,200 12,200 13,300 14,500 5 9,000 9,700 10,500 11,300 12,300 Slide 73 *The no-load loss evaluation ( /kw) specified in tenders from an EU power transformer plant during 2011. The values shown in this figures are snap-shots of several design specifications submitted to ABB

Jämförelse med en högre förlustvärdering 16 MVA Po Pk 2.500 v.s 15.000 /kw 500 v.s 4.000 /kw Hur styr dessa förlustvärden: Kortslutningskrafterna Inkopplingsströmmen Temperaturen Ljudet Danmark, leverans 2012 Förlusterna Po Pk 4.200 v.s. 18.700 /kw 2.000 v.s 8.000 /kw Överspänningståligheten Slide 74

TCO (Price+value of losses ) % Effect of high No-load Loss Evaluation (NLLE) Price and losses Background Origin of transformer losses Global climate discussion Driver for Energy efficiency Transformer optimiation process Loss evaluation Effect of high no-load loss evaluation Effect of high load loss evaluation Real case study (N1) Current R&D activity Summary 125% 100% 75% 50% 25% 0% -25% 100% 95.8% 2500 15000 No-load loss evaluation in EUR/kW Load losses No-load losses Price Over voltage limit 110% 121% Higher reliability from system voltage fluctuation or saturation due to DC current Noise Level 78dB 67dB (-11 db) Inrush current 100% 93% Lower system fault caused by transients No load losses 100% 69% Lower cost of losses TCO Slide 75 Load loss is fixed at 2.000 EUR/kW

TCO (Price+value of losses ) % Effect of high Load Loss Evaluation (LLE) Price and losses Background Origin of transformer losses Global climate discussion Driver for Energy efficiency Transformer optimiation process Loss evaluation Effect of high no-load loss evaluation Effect of high load loss evaluation Real case study (N1) Current R&D activity Summary 125% 100% 75% 50% 25% 0% -25% 100% 80% 500 4000 Load loss evaluation in EUR/kW Load losses No-load losses Price Short Circuit forces: 50 N/mm 2 20 N/mm 2 Reliability against SC event Winding temperature gradient: 20 C 5 C Run time at OFAF without pump: 20min 110min Energy efficiency and low noise No- load loss is fixed at 10.000 EUR/kW Slide 76

TCO: Price and cost of losses Energy efficiency in power transformer (real case Denmark) Life cycle analysis Energy efficient transformer could be 14% heavier 23% more expensive Background Origin of transformer losses Global climate discussion Driver for Energy efficiency Transformer optimiation process Loss evaluation Effect of high no-load loss evaluation Effect of high load loss evaluation Real case study (N1) Current R&D activity Summary 100% 75% 50% 25% Price Cost of no-load losses Cost of load losses Much smaller foot-print (CO 2 e) 100% 75% 50% 25% but.. Environmental impact (Global warming potential ) 0% Typical design (4200/2000) Delivered to N1 (18700/8000) Loss evaluations in EUR/kW (NLLE/ LLE) 0% Conventional solution Energy efficient solution : Using ABB light LCA tool Slide 77

A paradigm shift in transformers Price and value of losses Background Origin of transformer losses Global climate discussion Driver for Energy efficiency Transformer optimiation process Loss evaluation Effect of high no-load loss evaluation Effect of high load loss evaluation Real case study (N1) Current R&D activity Summary 100% 75% 50% 25% 0% Price Cost of losses 31% 51% Scenario 1 (4200/2000) Scenario 2 (18700/8000) (Loss evaluations in /kw) 1: Typical designs before 2010: Typical transformer design optimized with loss evaluation of 4,200 /kw and 2,000 /kw for no-load and load loss 2: Energy efficient design delivered to N1: Energy efficient transformer optimized with loss evaluation of 18,700 /kw and 8,000 /kw for no-load and load loss Slide 78

Summary Background Origin of transformer losses Global climate discussion Driver for Energy efficiency Transformer optimiation process Loss evaluation Effect of high no-load loss evaluation Effect of high load loss evaluation Real case study (N1) Current R&D activity Summary As a global community WE ALL are responsible for our Planet Energy efficiency in T&D can contribute a lot, to the reduction of CO2 emission Energy efficiency is a clear industry trend in power T&D and appreciated by regulation For the R&D community, this is a huge opportunity for INNOVATION T & D utilities Action: Correct loss evaluation, Purchase based on TOC R&D community Action: scientific methods for energy efficiency Energy efficiency in transmission and distribution system Regulatory bodies Action: interest rates, energy price, inflations, life time EU and IEC Action: Policy and political frame work T & D manufacturer Action: R&D on reduction of losses Slide 79