Design limits and solutions for very large wind turbines

“ The more your system is optimised, the more your
wind measurement must be reliable and accurate.
Wind measurement techniques for wind energy
are progressing quickly. New sensors are being
validated, with high potential to cut down the costs
and lower the risks. The UpWind project acted
as a node to narrow down wind measurement
uncertainties. It helped translate innovation into IEC
standards, with support of the whole measurement
community ”
Peter Eecen, Work Package Leader, Energy Research Centre of the Netherlands (ECN)
2.2 Work Package 1A2:
Metrology
Challenges and main
innovations
Small improvements in the wind turbine’s performance
can generate significant additional revenues over its
lifetime. However, if there is too much measurement
uncertainty, it becomes impossible to anticipate the improvement
to the performance during field tests, and
therefore difficult to convince the industry to include
those innovations.
The design improvements resulting from the research
activities of the UpWind project will require validation
based on reliable and appropriate measurements.
UpWind therefore studied OR is studying metrology
problems related to wind turbine technology. In particular
the fluctuations in wind speed lead to large
measurement uncertainties, and sensors such as cup
anemometers often do not respond in a linear manner.
The objective of UpWind’s metrology activities was to
develop ways to signifi cantly enhance the quality of
measurement and testing techniques for wind energy
applications. The first part of the metrology task was
to identify the current measurement methods through
the metrology database, then to identify metrology
problems that need further work, and finally to consider
problems to advance wind energy metrology.
This task addressed both the fundamental activities
for supporting the sector growth (online measurement
database, revision of IEC standards), and validated
innovative measurement instruments, which could
potentially lead to large cost reductions. UpWind
acknowledged the following elements:
LIDARs are potentially reliable measurement instruments
for resource assessment, control strategies,
or wake monitoring.
The use and calibration method of sonic anemometers
for wind measurements were established,
and significant improvements are currently being
implemented in available products.
Onsite work is valuable for wind sensor comparison.
Design limits and solutions for very large wind turbines
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