GOwind - extended version

1. Ghent Ostend Wind Research Institute
Extended version
Founded in Ghent on 06 April 2011
Jeroen De Maeyer Confidential – Gowind! 1

2. GOwind!
Jeroen De Maeyer Confidential – Gowind! 2

3. Powered by AUGent
 Association Ghent University (AUGent) is grouped around Ghent University,
one of the two major universities in Flanders, Belgium.
 In total it is home to 5.000 researchers and 32.000 students.
 It has 11 faculties, of which the Faculty of Engineering and Architecture is
one of the biggest with 2200 students and 850 (a.o. 150 professors)
researchers working in different fields ranging from architecture, ICT,
materials as well as electrical, mechanical and thermal energy systems.
 The associate partners relevant for GOwind! are the university colleges
HoGent (Ghent, Belgium) and HoWest (Kortrijk, Belgium). Both are strongly
connected to the local SME-market and can rely on excellent and extensive
test infrastructure.
 AUGent promotes
application focused research and industrial collaborations
translating research results into economic activities
 More info and links at www.gowind.ugent.be
Jeroen De Maeyer Confidential – Gowind! 3

4. Disciplines vs. themes
University
association
Association
partners
Faculties
Societal theme
Research
groups
Traditional structure focussed on disciplines
SET is an application and domain specific multidisciplinary cluster
that pools the expertise from the research groups to bring added
value in the societal theme of sustainable energy technologies.
Jeroen De Maeyer Confidential – Gowind! 4

5. SET and GOwind
To be a single point of contact for external partners
Support existing industrial activities
• To stimulate application focused research activities in answer
to the multi disciplinary challenges residing in industry, i.e.:
Create new industrial activities
• To identify and build up a portfolio of research results that
can be translated in economic activities (spin-offs, licences)
• To set out and coordinate the actions (IP, valorisation
projects, ad-hoc financing, contracts) required in creating
these economic activities
GOwind!, the SET philosophy
on wind energy showing
our commitment to this theme
Jeroen De Maeyer Confidential – Gowind! 5

6. Table of contents
1. Research topics
2. Test infrastructure
3. Research groups
4. GOwind! and the knowledge triangle
5. Contact
Jeroen De Maeyer Confidential – Gowind! 6

7. Small, large and off-shore
 Small and medium turbines
 Large turbines
 Off-shore turbines
Jeroen De Maeyer Confidential – Gowind! 7

8. Research topics
Condition monitoring
Drive train
Blades
Tower
Foundations
Grid coupling
Jeroen De Maeyer Confidential – Gowind! 8

9. Blades
BLADES
 Composite blades
• Structural design of composites
• Fatigue of composites models
• Nondestructive inspection of composites using optic fibers
• Structural health monitoring using ultra sound polar plots
• Self-healing composite materials
 Smart blades
• Combined fluid-structural simulation
Jeroen De Maeyer Confidential – Gowind! 9

10. Structural design of composites
Advanced calculation environment:
 CAE/CAD:
SolidWorks, Catia
 Finite elements:
Abaqus, LS-Dyna
 Composite draping modules:
Catia/CPD, Simulayt
 Optimization software iSight
 UM software for kinematics and
multibody dynamics
 Access to HPC cluster
with 2000+ cores
Jeroen De Maeyer Confidential – Gowind! 10

11. Structural design of composites
 Adhesive joints in composite materials and hybrid materials
Simulation of “mode I” crack growth in a Double Cantilever Beam (DCB) specimen
Jeroen De Maeyer Confidential – Gowind! 11

12. Fatigue of composites
 Damage behaviour of fibre-reinforced composites under biaxial fatigue
loading
 Shape optimization with evolutionary strategies: coupling of Java master
routine, ABAQUS FEA analysis and Python scripting in a fully automated loop
for complicated optimization problems.
Jeroen De Maeyer Confidential – Gowind! 12

13. Fatigue of composites
Load sequence effect on damage-cycle history
1.0
0.9
0.8
0.7
Damage [-]
0.6 high-low sequence
low-high sequence
0.5
0.4
0.3
Cycle-mix effect on damage-cycle history
0.2
1.0
0.1
0.9
0.0
0 100000 200000 300000 400000 500000 0.8
No. of cycles [-] 0.7
Damage [-]
0.6 small blocks
large blocks
Residual stiffness models account for 0.5
0.4
stress redistribution and load history 0.3
dependence of damage evolution 0.2
(in contrast to Miner’s rule) 0.1
0.0
0 100000 200000 300000 400000
No. of cycles [-]
Jeroen De Maeyer Confidential – Gowind! 13

14. Self healing composite materials
 New SIM project on self-healing polymers and composites
- Focus on cold-curing resins for infusion of wind turbine blades
- Collaboration with Momentive Specialty Systems (formerly Hexion)
 Simulation of crack growth and self-healing
-> regaining of static and fatigue strength
Jeroen De Maeyer Confidential – Gowind! 14

15. Nondestructive inspection
 NDT-characterization of fibre-reinforced composites
C-scan of a delaminated carbon/epoxy composite
Polar scan Carbon/epoxy - UD Carbon/epoxy-fabric Glass/polyester - UD
Jeroen De Maeyer Confidential – Gowind! 15

16. Simulation of Fluid-Structure Interaction
 Simulation of interaction between deforming or moving structures and the
surrounding fluid (gas or liquid)
 Improved prediction of load on wind turbine blades
• Flow-induced vibration of turbine blades
• Additional motion when wake of blade passes tower
 Linked to so-called smart rotor blades
• Blade shape changes over wind speed and rotor speed to alleviate loads
 Fluid-structure interaction code Tango
• Used in several ongoing research
projects, on own cluster and HPC
• Validated with internationally
accepted benchmarks
• www.FSI.UGent.be
FSI2 benchmark: Flexible beam behind a
rigid cylinder in a horizontal channel
Jeroen De Maeyer Confidential – Gowind! 16

17. Tower/Foundation
TOWER/FOUNDATION
 Foundations
• Scour protection around mono-pile foundations
 Wave slamming
• Prediction of wave run up
• Predicition of structural stress
 Tower
• Impact of imbalance of blades onto tower
Jeroen De Maeyer Confidential – Gowind! 17

18. Scour protection mono-piles
 Test setup for scour protection
 Optimal size of bricks (riprap)
 Design method for cost-effective scour protection
based on dynamically stabile erosion protection
strategies
Jeroen De Maeyer Confidential – Gowind! 18

19. Offshore foundations
 Wave run-up of off-shore structures
 Simulation results are validated with
experimental results
Jeroen De Maeyer Confidential – Gowind! 19

20. Coupled tower/blades sim
 Kinematic analysis of rotating vertical
axis wind turbine with effects of
imbalance (due to small mass
differences between blades), resulting in
precession motion.
 Body Element Model
Jeroen De Maeyer Confidential – Gowind! 20

21. Drive train
DRIVE TRAIN
 Generator
• Design, simulation and prototyping of electrical machines
• Capex vs. Opex: impact of magnetic material choices on energy yield
 Control
• Maximum power poin tracking techniques for small wind turbines
• Model predictive control
• Sensorless control of electrical machines
• Vector control of permanent magnet electrical machines
 Polymer bearings
• Fretting fatigue
• Polymer tribology
Jeroen De Maeyer Confidential – Gowind! 21

22. Axial-flux generators
 Axial flux generator for small wind
turbines show excellent (low)
cogging torque and high efficiency
 Electrical, mechanical and thermal
design and simulation of the generator
 Prototype building
 Experimental results
Jeroen De Maeyer Confidential – Gowind! 22

23. Impact of magnetic material
 Optimisation of annual yield (opex)
for two magnetic materials with
a different cost (capex).
 Does a more expensive
material choice pay off?
Jeroen De Maeyer Confidential – Gowind! 23

24. Control of electric machines
 Efficient control, control of dynamics, field weakening at high speed
 Induction machines, permanent-magnet machines (PMSM)
 Modelling dynamical behaviour, stability studies
Stability study of a digitally controlled
vector controlled PMSM drive with PMSM drive
rotor position estimator by using the root locus method
Jeroen De Maeyer Confidential – Gowind! 24

25. Modeling of SMWT
 Full system model of small and medium wind turbines including the turbine
rotor, the generator and the power electronics.
 An important parameter in predicting the energy yield from wind turbines is
the Cp. Three traditional models are used. However in reality this Cp is
almost never observed due to suboptimal maximum power point tracking
algoritms.
Jeroen De Maeyer Confidential – Gowind! 25

26. Sensorless control
 Position sensors for electrical machines are costly and vulnerable. This leads
to additional black-out times.
 The use of sensors can be avoided by interpreting the electrical signals of the
electrical machines, this is sensorless control.
 UGent has patented technology in this field.
Jeroen De Maeyer Confidential – Gowind! 26

27. Grid interaction
GRID INTERACTION
 Grid coupling of decentralised units
• Multi-level converters
• Power electronics for improved power quality
• Advanced control in µ-grid operation
• LESTS aspects on eco-industrial parks
 Farm operation
Jeroen De Maeyer Confidential – Gowind! 27

28. Multilevel convertors
 Grid connecting wind turbines and large (offshore) wind parks
can benefit from power-electronics operating at higher voltages.
 Such higher voltage allow to reduce the power loses.
 Multi-level convertors allow DC/AC conversion (or vice versa)
respecting the voltage limitations of the switches
 A careful balance of the capacitor voltages is required
 Such balancing techniques
were developed at UGent
a.o. based on MPC for three
phase convertors.
Jeroen De Maeyer Confidential – Gowind! 28

29. Grid coupling
 Full three phase power grid inverters for decentralised energy resources. The
inverters implementing a three-phase damping control strategy.
 Such control strategy results in the inverter behaving resistively towards
unbalance and distortions in the grid voltage.
 Hence, the grid inverter supports the grid and improves power quality.
Jeroen De Maeyer Confidential – Gowind! 29

30. Wind turbines in µ-grids
 Small and medium wind turbines
can be incorporated into a µ-grid
wether or not connected to the
distributed grid.
 This incorporation requires special
control strategies and power
electronics. Our approach does not
require any additional
communication.
Jeroen De Maeyer Confidential – Gowind! 30

31. Model Predictive Control
 Wind parks: SELFISH CONTROL (one section) vs. SOLIDARY CONTROL
(global optimization)
 MPC using LIDAR information
 Challenges:
• Control over communciation
networks
• Hierarchical control
Jeroen De Maeyer Confidential – Gowind! 31

32. Eco-industrial park
 The potential of wind energy can only
be realised if wind turbines become
more accepted by the different stake-
holders. This is facilitated by technical
advances as well as non-technical
aspects.
 One way to structure and tackle these is
using and investigating the LESTS:
• Legal aspects
• Economical aspects
• Social aspects
• Technical aspects
• Spatial aspects
Jeroen De Maeyer Confidential – Gowind! 32

33. Condition monitoring
CONDITION MONITORING
 Optical sensors embedded in blades for condition monitoring
 Accelerometers to detect vibrations and wear
 Argus data-acquistion and communication platform to collect
sensor readings
Jeroen De Maeyer Confidential – Gowind! 33

34. Structural health monitoring
 Multi-axial optical fibre sensors + smaller diameter 80 m -> ideal for
embedding in composite structures
Embedded optical fibre
sensors showing no stiffness
degradation, and small
permanent strain
Jeroen De Maeyer Confidential – Gowind! 34

35. Structural health monitoring
 New FP7 project “SMARTFIBER”,
aiming at embedding wireless
miniaturized strain sensors
inside the composite blades
Jeroen De Maeyer Confidential – Gowind! 35

36. Vibrations
• Starting from a macroscopic discretisation of a physical structure bearing in
mind its basic function (e.g. Motor, axis, gear-box, ... )
• Goal is to gain a global insight in where to measure and where and how to
control
• The approach allows to include the impact of:
• Non-linear vibrations (amplitude dependent damping, ... )
• Control-loops (e.g. Motor/generator control with PID)
• Approach is ideally suited for
• Complex systems with only few sensors
• Evaluating and design passive compensation systems for absorption of
vibrations
Jeroen De Maeyer Confidential – Gowind! 36

37. Vibrations
 Torsional vibrations of coupled rotors:
• Transient vibrations
• Stationary vibrations
• Techniques for absorption of vibrations
• Experimental test setups.
 Rotor dynamics:
• Analysis and experimental modelling
• Non-linear vibrations
• Model reduction
• Experimental test setups
Jeroen De Maeyer Confidential – Gowind! 37

38. Argus
 Modular platform with user-friendly interface
for remote monitoring of plants of
decentralised energy resources
 Allows to include the sensor read out of
numerous sensors e.g. wind speed,
direction, humidity, inverter temp.,
grid injected power
 Possibility to remotely reset the power inverter
IP
network
(internet,
VPN …)
Jeroen De Maeyer Confidential – Gowind! 38

39. Exploitation
EXPLOITATION
 Wind conditions
• Floating LIDAR
 Noise
• Generation
• Propagation
• Annoyance research
 Repair and maintenance
• Planning
• System for lifting person and goods
Jeroen De Maeyer Confidential – Gowind! 39

40. FLIDAR
 Involved as subcontractor in the OWI project
 Floating LIDAR
 Structural analysis and stabilisation of buoy
Jeroen De Maeyer Confidential – Gowind! 40

41. Polymer tribology
 We have large experimental and
simulation capabilities, to test tribology
at different scales.
 Focus on polymer tribology
 Polymer parts in wind energy systems
can be used for:
• Bearing separators
• Braking systems
• Pitch and yaw drive components
 Such parts are able to leverage on the fact that
• Complex lubricating systems can be avoided
• Less maintenance is required even in the presence of foreign agents
• They weight less
• These are corrosion resistant
Jeroen De Maeyer Confidential – Gowind! 41

42. Tests on Large scale bearings
Experimental
Bearing stress distribution during loading
cycle
Numerical
Jeroen De Maeyer Confidential – Gowind! 42

43. Fracture and plasticity
 Setting up models understanding the physical process
 Model validation and correlation between simulations and
measurement results
 Performance parameters Experiment Finite element simulation
(digital image correlation) (parametric Python scripting)
First principal
strain (-)
Validation of model 0.035
Better interpretation
of experiment 0.000
Parametric
studies
Performance
parameters
Jeroen De Maeyer Confidential – Gowind! 43

44. Fretting fatigue
 In the gearbox (tool long at break position)
 In the blade pitch bearings (too long in fixed position)
UGent tool
 For FE simulation and modeling
 To simulate the crack initiation
 To simulate the crack propagation
F(x)
q(x)
σ axial
σ axial
Lap-joint
Jeroen De Maeyer Confidential – Gowind! 44

45. Acoustics
 Microphones array allows identification of sources and feeds propagation
models.
 Shortterm and longterm monitoring of windturbines at different sites, e.g. off-
shore during piling (C-power) and operation (BelPower).
80 16
75 14
Geluidsniveau (LX, 10min in dBA)
12
70
Windsnelheid (m/s)
10
65
8
60
Avg of L99 6
Average of Leq
55
Average of L10 4
50 Average of L50
2
Avg WindSpeed (10m-m/s)
45 0
250
500
750
0
1000
1250
1500
1750
2000
2250
2500
2750
3000
3250
3500
3750
4000
4250
4500
4750
5000
5250
Productie (kW)
Jeroen De Maeyer Confidential – Gowind! 45

46. Acoustics
 Annoyance research te Oostakker (turbines @ Volvo).
 Most noise is generated in the direction in which the turbine blades are
coming down and in case of higher wind speeds.
0.7
0.6
N
0.5
NE
0.8
S
Risk of high annoyance
0.4
Risk of high annoyance
0.6
0.3
0.2
0.4
0.1
0.2
0.0
0 5 10 15 20
N NE E SE S SW W NW
Rotations per minute Wind direction
Jeroen De Maeyer Confidential – Gowind! 46

47. Planning
 Industrial management
and planning.
 Lean manufacturing.
 Impact in terms of
efficiency and cost
of material kitting,
sequencing and downsizing
in the line assembly.
Jeroen De Maeyer Confidential – Gowind! 47

48. R&M activities of wind turbines
 Repair and maintenance activities on wind
turbines need to be minimised.
 Still such activities are required and one
needs to be able to perform them on a
save, (cost)efficient and (energy)efficient
manner.
 This project develops an efficient, user-
friendly electrical pulley for R&M
activities on wind turbines.
(in collaboration with FallProtec, Lux)
Jeroen De Maeyer Confidential – Gowind! 48

49. Table of contents
1. Research topics
2. Test infrastructure
3. Research groups
4. GOwind! and the knowledge triangle
5. Contact
Jeroen De Maeyer Confidential – Gowind! 49

50. Simulation tools
Expertise and know how in using, a.o.
 Matlab/simulink
 Mathcad
 CAD
 Abaqus
 Fluent
 Ansys
 Catia
 Comsol
 Python scripting
 Own software tools
+ HPC cluster with 12000+ cores!
Jeroen De Maeyer Confidential – Gowind! 50

51. SWT-Field Laboratory
 Field laboratory @ Greenbridge, Ostend (B)
 10 turbine masts operating as a field laboratory (not demo) for research
institutes and manufacturers
 Rearch infrastructure includes:
• Noise camera’s and microphone array to investigate noise propagation
• Acoustic camera for structural health monitoring
• Meteo-mast
• Mobile data aquistion system
incl. strain gauges, speed,
torque, voltage and current
sensors
Jeroen De Maeyer Confidential – Gowind! 51

52. Materials
Tribology
Fatigue
Fracture
µ-tomografie
Stress
Jeroen De Maeyer Confidential – Gowind! 52

53. Electrical test infrastructure
 Power electronics and electrical machines, e.g.
• 240kVA power source
• Test rigs for electrical machines
• Vibrations
Jeroen De Maeyer Confidential – Gowind! 53

54. Tribological characterization
Wind turbine Configuration
Applications
Laboratory Soete
•Braking systems
•Glides for yaw •Stick slip tester
bearing •Bearing tester
•Bearing elements
Morell Radial Bearing
Gliding elements
(POM, PA)
Medium scale flat Large scale flat
Ring Segments
Composite tester Plint
Jeroen De Maeyer Confidential – Gowind! 54

55. Large scale fracture and plasticity
Optical strain measurement
(digital image correlation)
Metal structure
Plasticity
2500 kN
Notch
Fracture
mechanics
“Medium wide plate” tension test Laboratory Soete large scale test rigs:
Tensile forces up to 8000 kN
Jeroen De Maeyer Confidential – Gowind! 55

56. Fatigue on different scales
Optical measurement of deformations
(monitoring of fatigue crack growth)
Jeroen De Maeyer Confidential – Gowind! 56

57. Table of contents
1. Research topics
2. Test infrastructure
3. Research groups
4. GOwind! and the knowledge triangle
5. Contact
Jeroen De Maeyer Confidential – Gowind! 57

58. Research groups (1)
 Mechanics of Materials and Structures – J. Degrieck, W. Van Paepegem
• Structural design of composites
• Fatigue of composites
• Nondestructive inspection of composites
• Wave slamming on offshore structures
• Structural health monitoring
 Acoustics – D. Botteldooren
• Noise sources and propagation from wind turbines and monitoring
• MER-reports (Environmental Impact Reports)
• Annoyance research
 Coastal Engineering – J. De Rouck, P. Troch
• Sour protection of foundation
 Mobility and Spatial Planning – G. Van Eetvelde
• Use of wind turbines in eco-industrial parks
Jeroen De Maeyer Confidential – Gowind! 58

59. Research groups (2)
 Mechanical Construction and Production - Laboratory Soete – P. De Baets
• Frictions, bearings, fretting fatigue,
 Electrical Energy Laboratory – J. Melkebeek, A. Van den Bossche, L. Dupré,
L. Vandevelde
• Electrical, magnetic and thermal design of electrical machines
• Power electronics
• Grid coupling and incorporation in µ-grids
 SYSTeMS – R. De keyser, M. Loccufier
• Control theory for low level control of individual components, model predictive control for
master control of wind turbines/farms, analysis and prevention of vibrations
 Fluid Mechanics – J. Vierendeels
• Computational Fluid Dynamics (CFD)
• Simulation of Fluid-Structure Interaction (FSI)
 Industrial management – H. Van Landegem
• Lean manufacturing, cost and efficiency impact of industrial planning
Jeroen De Maeyer Confidential – Gowind! 59

60. Research groups (3)
 Wireless & Cable – Luc Martens
• Impact of wind turbines on radar signals
UGent – Associate partners
 HoGent – Electrotechnics – P. Sergeant
• Design and testing of electrical machines
 HoWest – Electromechanics – K. Stockman, J. Desmet
• Grid coupling
• Test infrastructure for electrical machines
• Vibrations
Jeroen De Maeyer Confidential – Gowind! 60

61. Table of contents
1. Research topics
2. Test infrastructure
3. Research groups
4. GOwind! and the knowledge triangle
5. Contact
Jeroen De Maeyer Confidential – Gowind! 61

62. Knowledge triangle
 Applied research bounding on the fundamental research
• GOwind! part of SET and energy research at Ghent University
 Entrepreneurship
• Power-Link: networking partner in energy
• Greenbridge: incubator, science park and demonstrator
 Education
• Two Masters in Energy Technologies
• Institute for permanent education
 Networking
• Power-Link vzw
Jeroen De Maeyer Confidential – Gowind! 62

63. Master thesis projects
Academic year 2011-2012
 Modelling and emulation of small wind turbines
 Stability of LIDAR measurement buoys for the registration of
offshore wind velocity profiles
 Out-of-the-box design of a 50 meter rotor blade for MW turbines
 Numerical simulation of the flow around wind turbine blades
 Feasibility study on a tidal energy converter coupled to wind
turbines on sea
 Numerical study on the interaction between waves and monopile
windturbines
… much more to come in academic year 2012-2013
Jeroen De Maeyer Confidential – Gowind! 63

64. More information
Jeroen De Maeyer
p/a UGent-EELAB
Sint-Pietersnieuwstraat 41
B-9000 Ghent
T +32 9 264 79 14
M +32 471 58 88 32
Jeroen.demaeyer@ugent.be
www.GOwind.ugent.be
Jeroen De Maeyer Confidential – Gowind! 64