IEC TC88 : Wind turbines

Republic of Korea

Outline

New Proposal of Korea

Status of the WTs in Korea

Design & Motion Analysis of the FOWT

Conclusions

Roadmap of an On/Offshore WTs in Korea

New Proposal of KOREA

Standard for Floating Offshore Wind Turbine(FOWT)Title

Scope

Purpose

This work will aim to bring together expert knowledge from the wind en-ergy and offshore engineering industries in order to formulate a guideline specification of the design, analysis, installation and maintenance re-quirements for FOWT.

• To provide uniform methodology for assessment of the floating offshore wind turbine.

• Assessment of design, analysis, installation and maintenance of FOWT for a various types.

New Proposal of KOREACONTENTS

1 Scope2 Normative references3 Terms and definitions3.1 Terms3.2 Definitions4 Symbols and abbreviated terms4.1 Symbols4.2 Abbreviated terms5 General requirements5.1 Fundamental requirements5.2 Safety requirements5.3 Basic considerations6 Design requirements6.1 Introduction6.2 General6.3 Structural Categorization6.4 Design criteria6.5 Accidental loads7 Environmental criteria7.1 Environmental condition7.2 Wind, waves, current7.3 Water depth7.4 Ice7.5 Soil conditions7.6 Marine growth7.7 Earthquakes7.8 Scour7.9 Other environmental conditions8 Floating offshore wind turbine structure design and analysis8.1 Introduction

8.2 Type of hulls8.3 Hydrostatic stability8.4 Hydrodynamic response analysis8.5 Structural design and strength analysis8.6 Fatigue analysis8.7 TLP design and analysis8.8 SPAR design and analysis8.9 Barge design and analysis8.10 Other hulls design and analysis9 Mooring system design and analysis9.1 Fundamental requirements9.2 Safety requirements9.3 Design situations9.4 Design criteria9.5 Anchoring systems9.6 Corrosion9.7 Fatigue life9.8 Strength and fatigue analysis10 Fabrication, installation, inspection and maintenance

10.1 Introduction10.2 Structural fabrication10.3 Mooring system fabrication10.4 Transportation10.5 Installation operations10.6 Inspection and testing10.7 Maintenance and repair11 Materials, welding, and corrosion protection11.1 Introduction11.2 Steel11.3 Corrosion protection system11.4 Nonlinear materials12 Reference

Global WIND ENERGY 2000-2030 (in GW)

Offshore 40 GW Offshore 150 GW

Source : EWEA

Global offshore wind trend

Economics of Fixed type vs. floating type

Source : OTC

Resource of Wind Turbine in Korea

Source : KIER Wind Map v1.1

Classification Unit Onshore Offshore

TheoreticalPotential

Potential TWh/y 987 881

Capacity GW 369 309

Area km2 97,545 79,539

GeographicalPotential

Potential TWh/y 99 176

Capacity GW 37 62

Area km2 9,755 15,908

TechnicalPotential

Potential TWh/y 49 88

Capacity GW 18 31

Area km2 4,877 7,954

Water depth[m] Wind velocity[m/s] Energy density[W/m2]

Status of Wind Turbine Market in Korea• Period of 3-5 years in Wind turbine will invest 9 million dollar annually by Korea Government.

• Technology development plan for the future Market -“Development of floating offshore wind turbine systems” selected as Strategic Technology by Korea Government

• A distribution plan 2.25GW through Wind turbine by 2012.

-3MW, 5MW offshore wind turbine development

• Various offshore wind farm Investment Agreement in progress (MOU).

Company Location CapacityTimeframe(year

)

KUMHO industrial. Jeonnam Yeosu city ￦ 2000 billion

KOSPO(Korea southern power co.ltd) Busan city 350 MW

KHNP(Korea hydro & nuclear power co.ltd, Doosan)

Jeju city 30MW

DONGKUK S&C Jeonnam Shinan(Bigeum-island) 90MW Target by 2013

POSCO Jeonnam Southwestern Sea 600MW Target by 2015

HANWHA E&C Incheon-City Muui-Do(Island) 2.5 MW * 39 1step by 2012

Nanjido 100 kW

KIER 100 kW

Saemangeum 7,900 kW

Wolryeong 100 kW

Hangyeong 22,700 kW

Woljung 1,500 kW

Haengwon 9,795 kW

Seongsan 20,000 kW

Hoengseong 40,000 kW

Angang 30,000 kW

Daegwanryeong 102,890 kWDaegiri 2,750 kWUlleung-gun 600 kW

Taebaek 6,800 kW

Yeongyang 18,000 kW

Yeongdeok 39,600 kW

Pohang 660 kW

Miryang 750 kW

Gori 750 kW

Installed 277,995 kW

Yanggu 20,000 kW

Yanggu 19,500 kW

Gyeonggi 3,000 kW

Ansan 3,000 kW

Nuaeseom 7,500 kW

Taean 267,500 kW

Saemangeum 22,500 kW

Sinan 300,000 kW(1st 3MW)

Jindo 100,000 kW

Samdal 20,000 kW

Deokcheon 40,000 kW

Hangyeong 30,000 kW

Dongbuk 20,000 kW

Cheongsuri 3,000 kW

Gapado 27,000 kW

Gangneung 25,000 kW

Daegiri 40,000 kW

Pyeongchang 19,800 kWJeongseon 50,000kW Donghae 60,000 kW

Seokbo-myeon 160,000 kW

Gimcheon 200,000 kW

Sajapyeongwon 110,000 kW

Prospect WTs 1,630,000 kW

Sangdo 31,500 kWNansan 14,700 kW

Pyosyeon 20,000 kWGodeok 20,000 kW

Yangsan 8,000 kW

Installed wind farm Being installed wind farm

Status of Wind Turbine Market in Korea

R&D Roadmap of Wind Turbine in Korea

OnshoreSystem

Large scale Wind Farm DevelopmentLarge scale Wind Farm DevelopmentSite SearchingSite Searching

Component Analysis and Design

Component Analysis and Design

Component Localization and Export

Component Localization and Export Site testing & Supplying Medium

Sized Systems

Pioneering abroad Market for components

Site testing & Supplying MediumSized Systems

Pioneering abroad Market for components

750kW – Site test750kW – Site test

2MW – Site test2MW – Site test

Offshore wind turbineComponent Design

Offshore wind turbineComponent Design

10kW Manufacturing

10kW Manufacturing

Large Offshore wind farmSearching

Large Offshore wind farmSearching

Hybrid System DevelopmentHybrid System Development10kW-Site test10kW-Site test

Large scale Offshore Wind Farm Development

Large scale Offshore Wind Farm Development

Supply Small SizedSystems Pioneering abroad marketfor Components

Supply Small SizedSystems Pioneering abroad marketfor Components

Wind farm Construction in AsiaWind farm Construction in Asia

2MW – Design and Manufacturing

2MW – Design and Manufacturing

2MW Remodelingand Manufacturing

2MW Remodelingand Manufacturing

Component LocalizationComponent Localization

5~6MW Design and Manufacturing

5~6MW Design and Manufacturing

2MW – Site test2MW – Site test

3MW – ConceptDesign

3MW – ConceptDesign

3MW Design and Manufacturing

3MW Design and Manufacturing 3MW – Site test3MW – Site test

100kW-Site test100kW-Site test100kW Design and Manufacturing

100kW Design and Manufacturing

5~6MW – Site test5~6MW – Site test

Multi MW classOffshore Wind turbine Supply

Pioneeringabroad market for Components

Multi MW classOffshore Wind turbine Supply

Pioneeringabroad market for Components

Main Target

OffshoreSystem

Small System

Medium sized System Commercialization / Component Development

Large System Development /Component Localization and Expert

Large System Export/ Commercialization of Application technology

1st Stage 2004~2007 Technology development and Industrialization

2nd Stage 2008~2012Technology Accumulation

3rd Stage 2013~2018Creating new Industry

Analysis Models(Plan)

Model No. 1 2 3Platform Type TLP Spar Barge

Stabilized by Tether Tension Ballast Buoyancy

Position Keeping Tether Tension Taut Catenary Slack Catenary

Conceptual Design Framework

Design BasisDesign Basis

• Basic Requirement - Turbine Capacity, Motion Requirement• Environmental Condition - Water depth, Wind, Current, Wave, Ice etc

• Basic Requirement - Turbine Capacity, Motion Requirement• Environmental Condition - Water depth, Wind, Current, Wave, Ice etc

Initial DesignInitial Design

Structural Analysis Global/Local Strength Fatigue Analysis

Structural Analysis Global/Local Strength Fatigue Analysis

Hydrodynamic AnalysisHydrodynamic Analysis

• Hydrodynamic Data - Wind Load, Current Load - Motion Analysis : Motion RAO, Force Transfer Function• Time Domain Analysis - Platform Motion : Angular Displacement, Acceleration - Mooring Line Tension

• Hydrodynamic Data - Wind Load, Current Load - Motion Analysis : Motion RAO, Force Transfer Function• Time Domain Analysis - Platform Motion : Angular Displacement, Acceleration - Mooring Line Tension

• Hull Sizing• Mooring System• Loading Condition• Stability Check• Prediction of Motion Characteristics

• Hull Sizing• Mooring System• Loading Condition• Stability Check• Prediction of Motion Characteristics

Analysis Methodology & Procedures

STEADYENVIRONMENTAL

LOADS

DESIGNENVIRONMENTAL

CONDITION

VESSELSLOW FREQUENCY

MOTIONS

STATICMOORING SYSTEMDISPLACEMENTSAND TENSIONS

VESSELSWAVE FREQUENCY

MOTIONS

TIME DOMAINLINE

TENSIONS

DAMAGECONDITION

(incl. TRANSIENT)ANALYSIS ?

CRITICALMOORING LINE

REMOVED

DYNAMICCONDITIONANALYSIS ?

ANALYSISCOMPLETED

DYNAMICSTUDY

YES

NO

YES

NO

Design Basis

Environment(survival)

Significant Wave height

Wind Speed

Water Depth

Current Speed

Tide

Topsides

Platform Weight

Topside Weight

Draft

MotionMaximum Angular Motion

Tower Top Acceleration

Rotor

Diameter [m]

Maximum RPM

Maximum Tip Speed [m/s]

Shaft Tilt [degree]

Rotor Mass [ton]

Nacelle Mass(ton)

Tower

Height [m]

Diameter – bottom [m]

Diameter – top [m]

Thickness – bottom [mm]

Thickness – top [mm]

Mass [ton]

Overall CoG Location(above tower bottom, m)

X

Y

Z

Design Basis of WT Platform

Offshore Platform Type = ?

Horizontal Motion LimitsRotational Motion Limits

Acceleration Limits

Minimizing Heave Motion

Number of Mooring Lines

Simple Geometry

Pretension

Displacement

TLP Type

Total Weight

Topside weight

Steel Weight

Fixed Ballast

Displacement

Draft

VCG

VCB

GMT,L

Radius of Gyration (@ COG)

Rxx

Ryy

Rzz

Mooring Line Characteristics

No. of Line

Dia.

Elasticity Modulus

MBL

Results – Motion time Series(TLP)

SPAR Type

Total Weight

Topside weight

Steel Weight

Fixed Ballast

Displacement

Draft

VCG

VCB

GMT,L

Radius of Gyration (@ COG)

Rxx

Ryy

Rzz

Mooring Line Characteristics

No. of Line

Dia.

Elasticity Modulus

MBL

Results – Motion time Series(SPAR)

Characteristics of floating offshore WT for each types

TLP

Horizontal Motion, surge mode, has to be improved to meet excursion limitation which is generally 5% of water depth in offshore field Vertical motions are too good to be true Motion criteria, especially acceleration at the location of nacelle will be needed at the early design stage KG is higher than KB

SPAR

Permanent eccentricity is to be counter-balanced by the arrangements of the fixed ballast Simple structure KB is higher than KG Lowered KG by fixed ballast

SPAR Type

TLP Type

Conclusion

• At present, the technology of a floating offshore wind turbine is not established and studying continuously.

• Experts need to create a new standard to compare the calculation data of floating offshore wind turbine for various load cases.

• A new standard should be dealt with by experts separately(>IEC 61400-3)

Thank you!