offshore research measurements & focus on structural health monitoring
TRANSCRIPT
Offshore Wind Infrastructure
Application Lab (OWI-Lab)
For efficient and reliable offshore wind energy.
Offshore Wind Infrastructure Application Lab
A Flemish Funded R&D initiative that aims to increase the reliability and efficiency of offshore wind farms
OWI-Lab is embedded within Sirris, the collective centre of the Belgian technological industry.
Industrial Initiators of OWI-Lab
Industrial Coordinator Scientific Coordinator
Introduction
What does OWI-lab do?
Investing 5.5M € in test and monitoring infrastructure to support (offshore) wind power R&D in the whole industrial value chain 4 investment programs in R&D infrastructure
Platform to initiate local and European research projects together with industry and universities (SBO, O&O, FP7,…)
Innovation projects with / for companies in the wind power sector
OWI-Lab services
Laboratory testing Field testing (offshore)
Field testing: Offshore measurement campaigns Unique SHM solutions / R&D campaigns
Purpose of the monitoring campaigns: 1) Input for R&D / Optimizations 2) Asset Monitoring (O&M)
Datasets as input for component design
Get better understanding of the behavior how the turbines operate far shore
Monitoring for O&M optimization
Multi-purpose:
Vibrations
Corrosion
Temperatures
…
Dedicated offshore measurements & monitoring system for R&D
Ongoing R&D measurement & monitoring campaigns (MC’s) in partnership with universities
Structural Health Monitoring (VUB)
Corrosion Monitoring (VUB)
Drivetrain Monitoring (KU Leuven)
Drive Train
Dynamic Monitoring
Tower
Dynamic Monitoring
Foundation
Dynamic Monitoring
Corrosion Monitoring
Fatigue Monitoring
Which monitoring?
55 Vestas 3MW V90 turbines
Monopile foundations
46 km Offshore
Water Depths : 16 - 30m
1 Monitored Turbine: C01
72 Vestas 3MW V112 turbines
Monopile foundations
37 km Offshore
Water Depths: 16 – 29m
2 Monitored Turbines:
D06 - H05
Current locations for monitoring
Drive Train
Dynamic Monitoring
Tower
Dynamic Monitoring
Foundation
Dynamic Monitoring
Corrosion Monitoring
Fatigue Monitoring
Validation of SHM package
Ongoing research projects: Vibration-based Structural Health Monitoring (SHM)
What? Monitoring the dynamic behaviour of a structure
Why? lifetime prediction, fatigue calculation, Load monitoring, safety, O&M strategy
Already commonly used in civil engineering & aerospace
Example: Stone cutter bridge Hong Kong
(the most heavily instrumented bridge in the world)
Ongoing research projects: Vibration-based Structural Health Monitoring (SHM)
Ongoing project OWI-Lab conserning SHM in partnership with VUB: CONTINUOUS DYNAMIC MONITORING OF AN OFFSHORE WIND TURBINE
Why?
Excitations of wind and waves have an effect on the offshore wind turbine and are capable of exciting the exciting vibration modes avoid resonant behaviour
Gather insights in dynamic behaviour of wind turbine in offshore conditions input for new designs, optimization of structures
Minimize O&M costs (scour protection around monopile structures)
Identify the current state of the offshore wind turbine (i.e. after a storm the scour protection can be damaged can have an effect on the vibration modes)
Extend lifetime of wind turbine structure
Ongoing research projects: Vibration-based Structural Health Monitoring (SHM)
Why? Example: Identify the current state of the offshore wind turbine
Uncertainty: effect of scour on the dynamics of an offshore wind turbine and its lifetime
Scour = the process where the water current accelerates around the support structure and due to its acceleration picks up and transports soil particles (sand) away from the support structure
Ongoing research projects: Vibration-based Structural Health Monitoring (SHM)
Why? Example: Identify the current state of the offshore wind turbine
Scour affects an offshore wind turbine in 3 ways:
1. Lowering the seabed around the structure reduces the lateral bearing resistance that the foundation pile can mobilize, which may mean that the pile needs to be driven deeper into the seabed
2. Lowering the seabed makes the structure ‘longer’ lowering the natural frequency (can be detected through monitoring) can have implications for fatigue damage
3. A large scour hole will leave the J-tube free-spanning, which eventually may damage the cable if this effect is not taken into account
Ongoing research projects: Vibration-based Structural Health Monitoring (SHM)
Why? Example: Identify the current state of the offshore wind turbine
Current approach: prevent scour by dumping a layer of crushed rocks around the support structure
Costly solution
Scour protection requires inspection and maintenance throughout the lifetime
Ongoing research projects: Vibration-based Structural Health Monitoring (SHM)
How?
Continuously monitor vibration levels and evolution of the frequencies and damping ratios (especially interesting for monopile based turbines ; jacket structure is more stiff than monopile)
State-of-the-art operational modal analysis (OMA) techniques and the use of appropriate vibration monitoring equipment can give insides in natural frequencies, damping ratio’s and mode shapes (cfr. Aerospace)
OWI-Lab continiously monitors one monopile based wind turbine (Vestas V90) at the Belwind wind farm to get insights in the dynamic behaviour of the structure and evaluate new OMA-technique in partnership with VUB (Vrije Universiteit Brussel)
Approach field testing service Structural Health Monitoring )
Advanced post-processing
techniques for
continuous dynamic
monitoring
of the structure
(damping, frequency,…)
Automated Operational Modal Analysis
Measuring Accelerations
Identifying Dynamic
Parameters
Updating FEM-Model
Prediction of Stresses
Life-Time Assesment
Example data set: VIBRATION DATA
Drive Train
Dynamic Monitoring
Combining gearbox surface vibration data with internal flexible multibody models to retrieve information on the relevant parameters for the remaining life assessment of wind turbine gearboxes
High frequency sampled data
Input for MBS-model
CONTINUOUS MONITORING
OF GROUT USING OPTICAL
FIBER TECHNOLOGY
New Measurement
Concepts using optical
fibers
New Innovation Projects (EUROPEAN)
WIFI JIP: Analysing Wave Impacts on fixed turbines
Objective:
To improve the way effects of steep
(and breaking) waves are taken into
account in the design methodology of
fixed offshore wind turbines, so that
optimized offshore wind turbines can
be developed
http://www.owi-lab.be/
@OWI_lab
Group: Offshore Wind
Infrastructure
Application Lab
(OWI-Lab)
Thank you for your attention!