Integrated Wind Farm Design · • Introduction integrated design • Optimisation or development...

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Integrated Wind Farm Design Flow project P201102_004

Wind Farm Wake Modelling, Fatigue Loads and Control Bernard Bulder (bulder@ecn.nl)

Rotterdam; Windkracht 14 January 23rd 2014

Content

• Introduction integrated design • Optimisation or development of objectives • Project developments • Example

• Pieter Gebraad’s (DUT- DCSC) Presentation on

Controlling the wakes for improved wind farm operation

• Questions

Introduction – What is integrated design or system engineering.

Integrated design in the conventional sense is to bring designers from all disciplines together from the start of the project

Nowadays it translated into coupling of proven design tools of all disciplines to and control the design process through a single interface to determine all factors of an objective function. Benefits are: Cost reductions during the development / faster time to market Higher reliability of the design / less surprises during integration of the

system Ultimately lower cost of energy

WIND FARM INTEGRATED DESIGN

4

Integral optimization Levelised Costs of Energy

Component choice

WF operation

HVac vs. HVdc

grid operation

Optimisation - Cost of Energy

The Cost of Energy is depending on a large number of factors or cost components.

To evaluate the cost function it will be necessary to have (detailed) models of all (most) major costs & benefits (yield)

Some of these aspects are developed or upgraded int this project

Just an example LCOE model, see model of the Crown Estate (UK)

Project developments

The FLOW project has three main research lines: Upgrading and extending the wake modelling o Lot’s of small and larger improvements have been made in the code, especially for the

near wake modelling and atmospheric stability, which is now an input parameter. Developing a fatigue load model to predict the fatigue load influence due

to wind farm operation in relation to the design load o Model has been made, including meandering on the basis of the stochastic wind field

data. Model is being implemented into FarmFlow. Develop control strategies using the yield and load information o Apply ECN’s active wake control to influence the fatigue load and yield in a

demonstration project

Project developments

ECN’s FARMFLOW wake model is validate against full scale measurement of the EWTW , 5 N80 wind turbines of 2,5 MW

The overall wake effects are very well predicted

Example

Wind farm output and wind direction

High variability of power output Low(er) variability of power output

Project developments

Development of Fatigue Load prediction model:

Based on characteristic shape of the wake in front of each wind turbine in the wind farm for all wind speeds and all wind direction the ratio of the fatigue equivalent load is compared to the design loads according to IEC – 61400-1 standard.

Final result: the ratio of the actual fatigue equivalent load over the design fatigue equivalent load (for all load components) investigated.

Due to large amount of calculations use is made of a database method where the calculation are performed on a reference wind turbine

Project developments

Wind Farm control using active wake control: reducing the rotor axial

induction or deviating the wake from

the down stream machine

Results: Lower fatigue loads and; an increase in yield!

Presentation by Pieter Gebraad Controlling the wakes for improved wind

farm operation

Thank you for your attention

This presentation is a cooperation between DUT – DCSC & ECN wind energy.

Questions?

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