high quality power transformers for grid reliability

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High Quality Power Transformers for Grid

Reliability

Singapore Sept 22-23, 2008

Thomas FogelbergHead of Quality

ABB Power Transformers

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-Transformers enable efficient energy transfer in society

System System transformerstransformers

Generator Generator StepStep--UpUptransformerstransformers

The correct use of voltage & current is the key to efficiencyThe correct use of voltage & current is the key to efficiency

The workhorsesof the electricalsystem

The workhorsesof the electricalsystem

Reliability and availability in focus

Reliability and availability in focus

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transport

conversionefficiency line losses

productionprocess

net energy

motor efficiencybuildings

Primaryenergy

Electricalenergy

Trans-mission &

Distribution

IndustrialPlant

Motors &Drives Buildings

Drive &motor

systems

Processautomation

systems

Gridoperationsystems

Plantautomation

systems

Processautomation

systems

Transportsystems

BuildingInstalla-

tions

Energy efficiency: Optimum use of voltages & currents

Total electrical systemfrom transmission to distribution very efficient

Total electrical systemfrom transmission to distribution very efficient

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-The Purpose of the Power Transformer = Gear Box

� It is the long term available “Gear Box” for production and transport of electric power which counts !! It shall always work !!

� The “Gear box” shall be as efficient as today, 99.6 – 99.7 % !!!

� The efficiency of the transformer is not the major purpose, it is to work as a gearbox over 40 years to make the electric infrastructure system efficient

� You get the infrastructure efficiency from “94 % to 97 %” to go from� 66 to 110 kV

� 110 to 145 kV or 220 V

� 220 to 400 kV

� 315 to 765 kV

� 500 kV DC to 800 kV DC

� And soon on…

And the “Gear Box” helps you

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-Reliability of Power Transformers

300 MVA220/115/37 kVtransformer

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800 kVtransformer

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1200 MVA400 kVPhase Shifter

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� Engineering To Order business Concept

� From Unique Specification

� To One unique Power Transformer

� This Tutorial will describe some very important aspects in the process from making a proposal (tender) to manufacture and test the final Transformer

� The whole power industry needs more to discuss how we can mitigate the risks from designing grids/Substations, making Transformer Specs to manufacturing/installing and maintain powertransformers for over 40 years of service.

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Job Shop

Batch Flow

Operator Paced Line Flow

Machine Paced Line Flow

Continuous Flow

Volume

Com

plex

ity a

nd S

ize

Layo

ut a

nd F

low

Many unique products: one each

Many products:

low volume

Many products: medium volume

Several products:

high volume

One product: very high volume

Continuous flow: flow rigid

Line flow, equipment paced,

flow regular

Line flow, operator paced, flow mostly

regular

Cellular layout, flow varied with

patterns

Functional layout, flow extremely

varied

Large Power Transformers

Small Power Transformers

Distribution Transformers

HV Switchgear

GIS Substations

MV & HV Breakers

Machining & Components

LV Breakers

Insulation Materials

HV & LV Cables

MV Apparatus

Large MotorsSmall Motors

ETO ATO STD

T&D Products Complexity charter

PowerTransformers

Types of manufacturing processesTypes of manufacturing processes

Units perdesign < 2

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High Quality Power Transformers for Grid Reliability

� Market Background: The biggest Change since ever

� Loss Evaluations and impact on today's design

� Procurement processes

� ABB TrafoStar Technology and Design Consideration to build reliable transformers

� Manufacturing aspects

� Short Circuit Safe Design & Manufacturing&Testing

� Quality Management

� Summary remarks

Agenda

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World Energy InvestmentWorld Energy Investment

��

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� ��

� ��

� ��

� �! �

" #��$

� % � 72%

13%15%� �! �

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� % �

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�% ��

��$

( ( �

) * �

+ �

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( ( �

) * �

+ �

, �- ��$ ��

�% �

�( ��. ��/0

( 1 �

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( 1 �

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+ + � ��$

�! �2 2 ��$ �

��2 ��

+ + �

�

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Power Transformer World Market

� 1994 – 2004: About 500.000 – 600.000 MVA/ year

� 2004 – 2007: From 750.000 to double numbers

� 2008 – 2015: with base demand form Asia (China,India), further demand increase to be expected ?

� Huge Capacity Demand issue

� Material Prices increased 3 -5 times 2005 – 2007 !!!!

� Low or Stable Loss evaluations

Transformers for reliable

Power Quality

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Expected World Market ?

0

1

2

3

4

5

6

5000 10000 15000 20000 25000 30000 35000 40000 45000 50000GNP/Capita

GNP index

GNP/Capita

ChinaIndia

16000 USD/Capita

USCHSEDE

GNP development in old and growing countries

Transformers for reliable

Power Quality

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Many conflicting requirements on transformers

Optimization of� Electric fields� Magnetic fields

� Losses� Temperatures� Forces� Ageing� Noise� Transport� …...

Requires advanceddesign and engineeringcapabilities

Requires advanceddesign and engineeringcapabilities

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Net present value of future losses

� Energy value 1 kW at 0,02 �/kWh, 8600 h/Yr,

� Assume 3% energy value increase/Yr

� Assume 11% investment interest

� 2100 �/kW

0

50

100

150

200

250

300

350

400

450

5 10 15 20 25 30

NPV of loss per year, �

Loss per year, �

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Loss Evaluations values

31002300155012%

4200315021008%

6200465031004%

0.04 �/kWh

0.03 �/kWh

0.02 �/kWh

Interestrate

Example: 1 kW losses in 30 years 8600 hours per year

Stable values in customer specifications recently

Examples above are for No Load losses (=8600 h/Yr)Load Loss evaluations depend on load profile per day, months etcand are therefore a varying % of the full year value

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Evaluated cost versus material content

� Higher materials prices

� Higher loss transformer

Costs

Core and Conductor mass

Transformercost

Evaluatedloss cost

Total evaluatedcost

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Conclusions: Losses vs Costs of power transformers

� Losses are primarily defined by the relation between materials costsand loss evaluations

� In recent years key materials costs have increased by a factor of 3 to 5 times

� Loss evaluations have changed very little

� Increased costs of transformers� Risk for increased losses in transformers

� Loss evaluations determined by� Interest rate chosen for investment� Expected future energy prices

� What are future expectations?

Energy efficiency specifications neededEnergy efficiency specifications needed

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9-Qualitative discussion of materials utilization

��

��

��

��

��

�� !��

" �� !��

��

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Deregulation in the Western World ?

� The Electrical System Industry was working rather well up to the mid 80ies. But

� All actors wanted a change� Rational: Interconnections through countries/states in EU and US� Political: Competition in all public sectors was a motto, also in old infra-

structure areas

� Results:� From governmental bodies to profit making companies� Unbundling of Power – Transmission – Distribution� Difficulties to get a collected responsibility� A gradually change from long term commitments to short sighted

horizons� Fluctuations in electrical prices for all consumers

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What can be expected in the Future ?

� What could happen?

� Purchaser drives standards lower to reduce costs –Why?

� Key people have personal targets based on financial performance, project budgets, see case examples: ENRON ?,Subprime loans…?

� Engineering staff has been reduced to the extent that relevant experience has almost disappeared

� Inexperienced engineers may feel pressurised into supporting or making bad decisions

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� Decisions made in the procurement process determine the future reliability of the transformer. Skills, Knowledge ?

� What is the risk?

� Transformers are supplied that are not fit for purpose!

� Long term reliability of whole family groups will be compromised

� Background

� Transformer prices/costs have risen sharply

� Lead times are pushing out to three years or more

� But, procurement is being driven by cash conscious asset managers, or even worse, non or less technical procurement people

� This might lead to a pressure to cut corners to reduce costs through ignorance or lack of competence

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� How has this developed?

� Reduction in technical expertise due to privatisation and regulatory driven cost pressures

� Senior utility managers are focused on cost and not the technical aspects

� Short sight horizons

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� What do we need to do?????

� Stop the problem at source

� How do we do that?

� Educate senior management of the importance of the key decision points in the procurement process

� Raise the profile of these key steps

�Specification

�Design review of overall technology used in the order, consistency, experience, track records

�The importance of correct and accurate testing

� That’s why I am here now !!!!!!!!

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� Power Transformers are known as very Reliable Products

� We are going through the biggest Market change since ever

� Will the Reliability numbers stay the same ?

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� Summary remarks

Agenda

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Power Transformer ETO Process

� The ETO Business Process of Power Transformers consists of � Tender

� Order design

� Manufacturing

� Testing

� Shipping

� Site erection and commissioning

� Lead by Quality Management

� Continous Improvement and R&D

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ABB’s Global Transformer Plants in ETO business

USTSLSt.Louis, USA

CNTPHHefei, China

THABBBangkok, Thailand

INABBVadodara, India

ESABBBilbao, Spain

TRABBIstanbul, Turkey

DETFOBad Honnef, Germany

PLABBLodz, Poland

CATRMVarennes, Canada

CNCTCChongqing, China

BRABBGuarulhous, Brazil

ESABBCordoba, Spain

SETFOLudvika, Sweden

Footprint 14 PlantsCapacity 200.000 MVACapacity 1.500 UnitsHeadcount 5000 Employees

CNZTCZhongshan, China

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Reliability of Power Transformers

� Engineering To Order business Concept� From Unique Specification

� To One unique Power Transformer

Requires on the Manufacturing side

� Rigid well proven Technology

� Orderliness and Clarity in all procedures and documentation

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ABB TrafoStarTM Technology

� Common Technical Standards

� Common Standard drawings

� Common Material Specifications

� Common Method Provisions

� Common Quality System

� Common Tooling and Equipment

� Common Design rules

� Common Design process

� Common IT design tools/software

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ABB TrafoStarTM Technology Modularization

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A global Business Concept

� Basic Product Design Rules, Transformer Physics

� Product order design process & IT tools, Design Modules, Global Release system

� Methods and tools for product manufacturing� Method Provisions/Instructions and Common Tooling

� Material/Component specifications

� Planning, Capacity reservation

� Supply Chain Management, contracts/audits, delivery times


� Testing � Training, global HR interactions, Knowledge Communication Center

� Global Feedback System

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Key parts of Power Transformer technology:� Product design rules physical design and dimensioning rules

� Order design methods and tools engineering of specific unit

� Manufacturing methods and tools produce actual unit

Basic product design rules , Transformer Physics

• Basic Dielectric• Acoustics• Transients and 3D Electro-Magnetic Simulations• Load Losses and Thermal Performance• Core Performance• Short Circuit Strength

Product order design process & tools

Methods and tools forproduct manufacturing

Trans-former

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ABB TrafoStarTM– Basic Dielectrics

� What is the definition of margin?� A margin must be defined towards a probability to a failure

� Transformers could be designed for a probability for 1 failure of 1000 units

Probability for an electric breakdown

0,0%

0,1%

0,2%

0,3%

0,4%

0,5%

0,6%

0,7%

0,85 0,90 0,95 1,00 1,05 1,10 1,15

Relative design criterion

Pro

babi

lity

for

a br

eakd

own

10% over stress means that the risk for an electric breakdown is approximately 3/1000

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� Electric breakdown strength is depending on:� Material properties

� Permeability

� Conductivity

� Direction of the stress� Stress perpendicular to a surface

� Stress along a surface (creep stress)

� The amplitude of the electric stress

� The duration of the stress� Service stress

� Transients

� It takes some time to flash over

� Short duration is permitting higher stress than long

� AC or DC� In AC fields the stress is governed by the capacitances

� In DC fields the stress is governed by the resistivity

Duration

E [kV/mm]

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� Mixing materials� Materials with higher permeability

are pushing the electric field in to material with lower permeability

� Oil has lower permeability than cellulose

� Cellulose is stronger than oil

ε1 ε2

E1 * ε1 = E2 * ε2

Material 1 Material 2

Conductor Conductor

Stress in oil wedge

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Reversible Reversible

Irreversible

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3-D 2-D, cylindrical

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Standardized winding end stackswhich are automatically optimized by

electrical design system

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Brazil - ABB+CEMIG 145kV TransformerBrazil - ABB+CEMIG 145kV Transformer

ABB+CEMIG 145kV ABB+CEMIG 145kV TransformerTransformer

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ABB TrafoStarTM– Core Performance� Generate Accurate Calculations of:

� Core loss� Magnitude & harmonic content of exciting

current� Number of cooling ducts in the core� Core hot-spot and core surface hot- spot

temperatures� Using unique Anisotropic 2 D model of

stacked cores

PAST

PRESENT0%

2%

4%

6%

8%

10%

ABB Plant

Mea

s/C

alc

Std

ev [

%]

0%

2%

4%

6%

8%

10%

ABB Plant

Mea

s/C

alc

Std

ev [%

]

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ABB TrafoStarTM– Acoustics� Accurate calculation of No-load Noise -

level considering: � Core steel magnetostriction characteristics � Core type, core geometry, type of core joints, flux density,

and frequency� Sound radiation properties of the transformer

� Accurate calculation of Load Noiselevel considering:

� Physical properties of windings and insulation

� Accurate calculation of core & tank

Resonance Frequencies� Allows accurate prediction of noise-level at design stage� Avoids serious noise-level problems

� Accurate Calculation of Frequency Spectrum

� Considering No-load, Load, Current harmonics and DC magnetization

� Identified and developed a number of noise reduction techniques

� Core steel / Tank design / Tank damping / Vibration isolation

� Novel technique for sound reduction in oil

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ABB TrafoStarTM– Acoustics

93 MVA Transformer

� Size equivalent to a 250 MVA Transformer

No – Load Noise: 44.7 dBA

Load Noise: 53.4 dBA

Total Noise: 53.9 dBA

[Typical Total Noise: 75 dBA]

65 MVA Transformer

� Size equivalent to a 200 MVA Transformer

No – Load Noise at 100% V: 49.6 dBA

Load Noise at 100 % I: 51.6 dBA

Total Noise: 53.7 dBA

[Typical Total Noise: 72 dBA]

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� Load Losses- Both the total load losses according

to the Contract, and the detailed lossdistribution are thoroughly calculated

- The figure shows an example of thethree loss types in a windinga) DC-loss (grey)b) Axial eddy loss (blue)c) Radial eddy loss (red)

- Well-known loss distribution in windingsand structural parts in active part and tank�� dangerous hot-spots are avoided�� improved serviceability of the transformer

ABB TrafoStarTM Load Losses and Thermal Performance

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ABB TrafoStarTM Load Losses and Thermal Performance

Minimize the risk of hot spots in tank and constructional parts� training of electrical engineers� 3D Simulation user support network� best practice guidelines� simulation for different transformer designs

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ABB TrafoStarTM - Short Circuit strength

� Setting the criteria for permissible mechanical forces at fault currents

� Producing Mechanical Calculation Programs

� Follow up on Short Circuit tests

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ABB TrafoStarTM - Short Circuit strength

� Mechanical model for spiraling in 3 D Simulation

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ABB TrafoStarTM - Simulations

DesignPower Transformer manufacturing is an ETO business:

Elaborated simulation tools are essential and provide:

� Simulation Know-How� Development of design tools

� Simulation support & design rules

Simulations

Design Tool

Simulation Guide Training

Result

Design Rules

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3D Design Verification• Once the transformer is modelled in 3-D,

the models are used for analysis and verification.

• Electrical stresses can be mapped andevaluated

• Electrical clearances are checked.• Mechanical interferences can be verified.• Magnetic losses and temperatures in structural parts can be calculated

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Dielectric Simulations

(ACE, Simulation toolbox)

Transient Simulations

(WINTRAN)

Electro-thermal Simulations

(Infolytica)

Electro-mechanical Simulations

(Infolytica/Toolbox/ABACUS…)

SpecTra 5.4

Shielded Windings

…

Insulation projects

…

Spiraling forces

…

Core design

…

Example of Design Tools:

• For Engineering and Development work

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ABB TrafoStarTM Standard Documentation

� Technical Standards

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� Method Provisions

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� Material Specifications

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� Sigma Cards & Instructions

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� Test Standards - A set of common Test Standards is used by all plants to secure that the tests are made in the same way in all ABB test rooms

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Newsletters All new tools or methods are communicated via electronic Newsletters, distributed toProduction and Operations Managers in particular plants. Copies of Newsletters are alsolocated in commonly available LN database


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Uniform ToolingAll standard tools and equipment are described in commonly available in Uniform

Tooling database, including: specification, sourcing information and price of every tool. We constantly make sure our equipment is up to date and up to recent available technology.


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8- The follow-up of Metrics is an important

tool to judge performance and to make benchmarking between transformer plants


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TrafoStarTM – Design Process

� Total Design Process

� Design Quality Assurance/ Design Review

� Basic Design

� Performance calculation

� Design verification

� Creation of design elements

� Integration of modules

� Verification using 3D CAD models

� Design for Short Circuit Strength

� Design for Transport Forces

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TrafoStarTM – Total Design Process

Quotation Elec Design Mech Design Manufacture Test

Forecast Material supply

Order clearing

Design review

Design approval Inspections WitnessCustomer

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TrafoStarTM – Design Quality Assurance / Design Review

Quotation reviewOrder clearing (Int and Cust)Pre-DesignPeerTestApproval (Int and Cust)

Pre-DesignPeerCross-checkApproval (Int and Cust)

Test Report

Quotation Elec Design Mech Design Manufacture Test

Pre-start introLogisticsInspectionsAudit

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TrafoStarTM– Basic Design

� Basic Design parameters such as current density, flux density, winding turns, winding configuration and core dimensions are all optimized using the TrafoStar computer design tool Spectra, to achieve minimum Total Operating Cost

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TrafoStarTM - Performance calculation

� No Load Losses

� Load Losses

� Noise Levels

� Temperatures

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TrafoStarTM - Design verification� Transients

�Voltage distribution�Stress calculation

� Magnetic flux�Losses�Temperatures�Forces

� AC Test�Electrical stresses

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TrafoStarTM - Creation of design elements

� Computer calculated geometry.

� Automatic creation of manufacturing documentation for Windings, Core and Clamping structure.

� Automatic Winding Exit design

� Templates for Tank, Conservator using pre-defined modules.

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TrafoStarTM – Integration of modules

��#�� #��

� Proven design modules are maintained in a global library.

� These are re-configured or used directly.

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TrafoStarTM - Verification using 3D CAD models2D and 3D electric and magnetic field analysis� After a 3D model of the transformer

has been created it can be used for analysis and verification.

� Electrical stresses can be mapped and evaluated

� Magnetic flux losses and hot spot temperatures can be calculated in structural parts

� Mechanical clearances can be verified.

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Implementation Management in huge corporations

� Implement Design Technologies from global Design Development Team � All instructions and revisions available on the corporate network. Notifications are

sent out to keep everyone op to date.

� The IT design tools receive yearly releases

� Huge staff of design and IT engineers in global centersl

� ABB drives a Knowledge Communication Center in Germany where employees are educated and certified

� Secure and spread know-how

� Same engineering and production process

� Improved contacts between factories

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� Summary remarks

Agenda

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TrafoStarTM Manufacturing Process

Winding Winding Assembly

Active Part Assembly VP Drying Final

Assembly Test ShippingCore Building

Cleats & Leads

Core Cutting

Tank Manufact.

Planning & Scheduling

Internal Transport

Materials Receiving

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Core

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Core

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Winding

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Assembly

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Assembly

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Test

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Test

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Shipping

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9-Reliability of Power Transformers

� Testing of Power Transformers

� Dielectric Tests� Seems OK today but “all” people talk about it

� Thermal Tests� Accuracy in Cold Resistance ?

� Are we measuring ambient correct ?

� Is Top Oil well defined ?

� Heat Run stability ?

� Is winding temperature average enough?

� Mechanical Tests� This is the issue Today !!

� Are we making Short Circuit tests ?

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� ABB TrafoStrar Technology and Design Consideration to build reliable transformers




� Summary remarks

Agenda

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Short - Circuit Withstand Capability

� Why talking about Fault Currents in network today ?

� Are Fault Currents affecting Transformers more today ?

� Who cares about Mechanical Forces in transformers ?

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Short - Circuit Withstand Capability

� History – Why SC tests ?

� SC tests have been used in different countries

�Reasons: Customers didn’t get SC safe transformers

� SC tests introduced 1950 -1960

� SC tests have been debated during the years

�Many opinions in different countries about the needs and what one test shows

� IEC has edited new revised Standards

� SC tests seem very relevant to discuss today !?

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3-Short - Circuit Withstand Capability

� Expanding cross-border electricity trade brings network operations close to their physical limits

� Development of wind generation integrates regions without taking into account available network capacities

� Load flows are changing

� Network components are ageing

� The network operation conditions have changed

� New and old transformers will see more severe SC duty than before

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� Loss Evaluations are the same or lower since interest rates have been set higher after the privatization

� Material prices (Copper, Core Steel, Oil, Electrical Board) have increased by a factor of 3 – 5

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5-Qualitative discussion of materials utilization

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� How will all those changes affect today's transformer designs ?� There are now more strong temptations to save active material

and/or go closer to mechanical limits !!??

� Are tenders from SC point of view comparable ?

� Does the Industry have efficient measures/test Standards to check the mechanical integrity of such infrastructure products like Power Transformers ?

� New IEC SC standard proposes� SC Tests or

� Design review evaluation/verification � IEC proposes typical allowable, critical stresses

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7-Short Circuit Integrity

Electromagnetic forces tend toincrease the volume of high flux or minimize the magnetic energy density in the volume

• Inner winding towards reduced radius

• Radial Forces

• Outer winding towards increased radius

• Radial Forces• Winding height reduction

• Axial Forces

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Radial forces failure modes:

- Buckling of inner winding

- Diameter increase of outer winding

- Spiralling of end turns in helical winding

Axial forces failure modes:

- Mechanical withstand of yoke insulation, core clamps and spacers

- Conductor tilting- Axial bending between spacers- Telescoping

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Buckling of inner windings

Unit removed after 15 years of service due to increased impedance.

Note: No electrical damages

250 MVA, 400 kV auto

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Short Circuit Integrity

B B Fax Fax

B B Fax Fax

- Gaps in a winding will create large variations in the radial component of the leakage flux

- Consequently, large axial forces will be developed

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Excessive axial forces towards yoke

Damages from a SC test

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Inner winding Outer winding

Spiralling

A tangential shift ofend turns in helical type windings

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� Spiralling on the winding of a 370 MVA GSU transformer during the short-circuit withstand test.

� a) entire outer layer of the LV winding

� b) detail of the upper lead exit on the same layer heavily bent and distorted

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4-TrafoStarTM Design for Short-Circuit Strength

Design with respect to radial forces:

� All windings are radially self supporting

� Inner windings are subject to “free buckling”� No radial support

� A dynamic phenomenon

� Strength is determined by Cu hardness (yield point) and conductor geometry

� Outside windings are subject to tension� Strength is determined by Cu hardness

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5-TrafoStarTM Design for Short-Circuit Strength

Design with respect to axial forces:� Axial forces are calculated by FEM

� Considering axial displacement due to workshop tolerance

� Considering axial displacement due to winding pitch when applicable

� Windings are dimensioned for maximum compression forces

� Dynamic effects are considered by dynamic factors on the forces

� Winding ends are dimensioned for

� maximum unbalance forces and

� a part of the maximum compression force (“Bounce Back”)

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6-TrafoStarTM Manufacturing aspects and accuracy

Strict ManufacturingProcedures and Tolerances

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7-Short Circuit Strength Verification

IEC gives two options to verify the ability to withstand thedynamic effects of a Short Circuit, IEC 60076 – 5: (2006-2)

� By full SC test at a certified lab, or� By theoretical evaluation of the ability to

withstand a SC event by manufacturer’sexperiences supported by IEC guidelines.

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TrafoStarTM Short Circuit Strength – Verification by testing

• 35 TrafoStar short-circuit tested 1997 – 2008 Sept

• 7 with voltage 400 kV or above

• 10 rail track feeder transformers

• 3 test failures 32 / 35 = 91 % first pass rate

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100

150

200

250

300

1997 1998 2000 2001 2002 2005 2005 2007 2008

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9-Short Circuit Tests at KEMA

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12

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25-50 50-100 100-200 >200

MVA (rated)

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initially OK

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20-100 100-200 200-300 300-400 >400

kV (rated)

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initially OK

� 25 -30% of large transformers (> 25 MVA) fail to pass initially short-circuit tests.

� No common root-cause

KEMA numbers published at CIGRE 2006

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� From the statistics it seems that there are large differences in the number of SC test failures among manufacturers

� ABB has done the most number of tests during the years and have got a large amount of feedback and experience

� ABB is using simple physical rules to calculate forces and applies modest critical stresses

� ABB has stringent manufacturing control on winding related dimensions and processes.

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01-Short Circuit Recommendation

� All transformers are Dielectrically and Thermal tested� Some very few are SC tested

� Customers shall consider in tender documentations to include new 60076-5@IEC:2006� Always to require manufacturers’ stresses compared with their

allowed or critical values, deviations to IEC guidelines to be commented. Design reviews to be required

AND/OR

� Mention in the specs that customer considers the rights to ask for SC tests one month after the order signature.

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02-ABB Short Circuit Recommendation

� What units to be SC tested ?

� Important Generator Step Up transformers and Auxiliary units in Power Plants

� Key feeding transformers at Power plant Sub Stations or huge load centers

� Strategic Intertie Transformers� 3 winding system transformers (Tertiary), Autos

� Transformers with helical windings and axial split winding connections

� Series of transformers, one to be taken out

� Always Track feeding transformers

� Transformers connected to networks known for many faults and high fault currents

� All Power Transformers designs/contracts to be checked by designreviews acc to IEC 76 Part 5 (2006-02)

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TrafoStarTM Strategic Transformer Components

� ABB uses it own manufactured Components� On and Off Load Tap changers

� Bushings

� Insulation material and Insulation Components

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04-TrafoStarTM Electrical Components

On-Load Tap Changers

Off-Circuit Tap Changers

Bushings

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TrafoStarTM Insulation

Outlets & Moulded Parts

Winding Kits

Active partInsulation Kits

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06-TrafoStarTM– Kit Insulation Systems

Delivers ready for useon the winding mandrel improving…

� Productivity

� Space utilization

� Material flow

� Inventories

� Capacity

� Quality

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TrafoStarTM Quality Management System

� Quality Assurance in Sales, Project Management, Technology & Design, SCM, Production and Testing

� Continuous Improvement Process

� Quality Assurance in Packing, Transport & Site Assembly

� Training and Education

� Test Failure Management

� Benchmarking

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� Quality Assurance in all Business Processes

Project Management

Supply Chain

Mgmt.Production

Packing & Transport

Installation & Commissioning

TestingTechnology& Design

Front End

TrafoStarTM Quality Management System

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TrafoStarTM Quality Assurance in Front End

� Customer requirement review

� Design review process� Concept/pre-design review

� Process for Novelties� Novelty Risk Assessment

� Process for introduction to manufacturing

� Hand-over process� Sales to Electrical Design

� Electrical to Mechanical Design and Test

� Mechanical Design to Supply Management and Manufacturing

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� Designer Qualification� Education

� Experience

� Design Capacity� Number of designers

� Access to expert support

� Know-how development� Formal and informal training

� Job rotation

TrafoStarTM Quality Assurance in Technology & Design

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� The level of vertical integration is very different for different manufacturers� Supplier Qualification Process

� Supplier Quality Inspections

� Supplier Audits

� Supplier Performance Monitoring

� Continuous Improvement Process

TrafoStarTMQuality Assurance in Supply Chain Management

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AUDIT PROGRAM FOR GLOBAL & REGIONAL SUPPLIERS 2007

Supplier Country Commodity Date1 Kawasho Singapore Slitting of electrical steel H. W. Kropp2 Cogent UK Electrical Steel H. W. Kropp Audited 20053 AK Steel USA Electrical Steel Troy Mullen/US4 Posco Korea Electrical Steel H. W. Kropp5 Vicente Torns Spain Copper conductors6 MKM Germany Copper Foil7 KME Germany Copper Foil8 Dahrentrad Sweden Enamel copper wire9 Invex Italy CTC Hakan Wikberg/DE Okt10 Sam Dong Korea CTC & Enamelled copper wire Audited 200511 De Angeli Italy CTC12 Metrod Malaysia Copper conductors13 Metrod Thailand Copper conductors14 Hydro Aluminum Norway Aluminum Foil15 Comem Italy Accessories Hakan Wikberg/DE Nov16 Elmek Turkey Accessories17 Messko Germany Thermometers Hakan Wikberg/DE June18 MR Germany Tap-changers Troy Mullen/US19 Nynas Belgium Antwerp Hakan Wikberg/DE April20 Nynas Houston USA Hakan Wikberg/DE Sept21 Albert Maier GmbH Germany Radiator valves Bernt-Ove Hellström/SE Kari Miettinen/SE March22 TTP India Radiators Audited 200523 Sinjungwoo S. Korea Radiators24 ZPREP Poland Radiators Audited 200625 GE SYPROTEC INC Canada Sensors and Monitoring systems26 Zapel Poland Porcelain Richard Yngvesson/SE27 Munksjo Sweden Insulation paper Leif Hakman/SE28 Roechling Germany Pre-compressed wood Leif Hakman/SE29 Hexion (Bakelite) Germany Epoxy resin mix Rudolf Schutzeichel/DE

Auditors Number of Incoming Inspection Claim

05

10152025303540

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ASTA R&GMits

ui

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Q2

Q3

Q4

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Supplier Error Statistics 2007

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10.0%12.0%14.0%

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Coiltec

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Q2

Q3

Q4

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Number of Incoming Inspection Claim per Quarter

0102030405060

7080

-06 Average Q1 Q2 Q3 Q4 -07 Average

Supplier Audit Plan 2007 Supplier Performance Statistics-Example

Supplier Performance Statistics-Example Supplier Performance Statistics-Example


A B C D E F G H I

A B C D E F G H I J

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TrafoStarTM Manufacturing Process

Winding Winding Assembly

Active Part Assembly VP Drying Final

Assembly Test ShippingCore Building

Cleats & Leads

Core Cutting

Tank Manufact.

Planning & Scheduling

Internal Transport

Materials Receiving

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Inspection of coils prior to fitting outer wraps

Skills

Elec. Des, Mech.Des, QC, Manuf.

IC1: Winding

IC2: Conductor Material

IC3: Winding Insulation Material

IC5: Brazing Control SheetIC4: Preparation/Winding Assembly

1) Winding Process Control


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6 sigma measurements in the manufacturing of

windings!

Reduction of process variation

Windings•Shielding ring dimensions

•Former cylinder•Inner oil ducts dimensions•Winding radial height•Winding height•Winding exit protrusion•Winding exit lead stability

Winding Process Control Control Point 1 in Inspection Card 4


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Cost of poor Quality (COPQ)

Every Power Transformer Factory is committed to integrate the COPQ process into its Continuous Improvement Process.

Sales Proj.Mgt Engg. Supply Manufact. Transport InstallationCommissioning Warranty Support

Processes

TrafoStarTM Continuous Improvement Process

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TrafoStarTM Training & Education

� Knowledge Communication Center (KCC)The KCC is a channel between the factories for Benchmarking and the exchange of Best Practices

The KCC increases the competence throughout the corporation and within the Factories, encourages Teamwork and motivates employees.

Training and Education is key in the approach for operational Excellence. Highly skilled and motivatedemployees are a precondition. Employees must be given continous education and training.

Knowledge Communication Center - KCC

� Operational Excellence Program (OEP)The OEP Program helps to develop Resources,increase competences and break down barriers.

� Quality SchoolEvery Power Transformer Factory has a Quality School with an education program and a dedicated Classroom. The contents of the Training should be adapted to the maturity and existing knowledge and specific needs. Objectives of the Quality School are:

�Reinforce training and education in all key areas �Secure good knowledge management and secure technicalcompetence�Estabish a formalized communication channel to all employees

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TrafoStarTM Test Failure ManagementThe worldwide analysis of test failure is very critical !!The data provides the opportunity to learn,

analyze and prevent recurrence. This helps us to continuously reduce our test failures and to reduce costs associated with poor quality. It also helps us to identify gaps in our guidelines, method provisions or work instructions.

Rules for Reporting and Management of Test Failures are described in an instruction. At least 3 times per year, a team of experts analysis all Test Failures on a global base anddefines corrective actions.

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Having global manufacturing footprint with 14 factories worldwide.Benchmarking and best practice implementation is driver for continuousimprovement

Process OK orimprovement

completed

On-goingimprovements

Gap to beclosed

Common Improvement

TrafoStarTM Benchmarking

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TrafoStarTM Platform – Global Feedback System

� Measured Core Losses

� Measured Load Losses

� Measured Sound levels

� Measured Temperatures

� Measured Impedances

� Measured Pd

� Short Circuit Tests

� Test Failures

� Field Failures

� Non conformances reports of key processes

� A number of Key Performance Factors for key processes in an advanced global Operational Excellence structure

All those performance data goes back to the ProductPlatform for maintenance, improvements and further developments !!

An organization of 50 global engineers in 5 plants and CRC labs

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Risk mitigation in the Power transformer procurement chain

� Recommendation for Customers� 1. Most important specification parameters

� Specification must be well structured and clearly written

� Specify all requested functions rather than solutions

� Avoid hidden requirements easily overlooked by engineers on the manufacturer’s side

� Eliminate all requirements which complicate the transformer

� Specify the dielectric test levels with sufficient margin

� Short Circuit Tests ?, prolonged Heat Run Tests ?

� Do not exclude design solutions because this may force a manufacturer out of his standards

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� Recommendation for Customers & Suppliers� 2. Basic important issues in a Design Review

� Check the design of the transformer for compliance with the service requirements

� Identify novelties and deviations from proven solutions

� Ensure that all vital functions are verified by testing

� Verify that all important stresses vital for the long term service reliability have been calculated and are within proven and experienced limits by the manufacturer.

� Verify that the design is a result out from a well documented engineering system and accurate, consistent engineering tools/systems (ABB TrafoStarTM)

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� Recommendation for Suppliers � 3. Material and Component Suppliers

� Ensure high quality material suppliers by Supplier Qualification

� Clear Material and Component Specifications ref to IEC and ANSI Standards

� Continuous Improvements

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� Recommendation for Suppliers� 4. Consistent Delivery Process and Quality System

� Well defined total process flow

� All manufacturing processes, equipments, tools are documented in Method Instructions

� Quality assurance in� Technology & Design

� Supply Chain Management (SCM)

� Production

� Testing

� Packing & Transport

� Installation & Commissioning

� Continuous Improvement Process guided by a structuredfeedback system from test measurements, field experience

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A global Business Concept……

� Basic Product Design Rules, Transformer Physics� Product order design process & IT tools, Design Modules, Global

Release system� Methods and tools for product manufacturing

� Method Provisions/Instructions and Common Tooling

� Material/Component specifications� Planning, Capacity reservation � Supply Chain Management, contracts/audits, delivery times� Quality Management� Testing � Training, global HR interactions, Knowledge Communication Center� Global Feedback System

For long term reliability

high quality power transformers for grid reliability

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