Tower design and analysis - Wind Power Generation and Wind Turbine Design - page 553

tower may be severely underestimated if the tower-blade coupling is not taken
into consideration properly. A simplifi ed gust factor approach for calculating the
response of wind turbine towers has been discussed. Two gust factors based on dis-
placement and bending moment response of the tower have been presented. They
have again highlighted the importance of tower-rotor coupling with the need for
response specifi c gust factors. The importance of wind tunnel testing has been dis-
cussed and emphasized. Since vibration poses a critical challenge in wind turbine
towers, vibration control strategies with TMD and other passive dampers have
been discussed. Mathematical models have been presented for both onshore and
offshore wind turbine towers. Joint wind and wave loading have been modelled for
analyzing the offshore towers. It has been observed that vibration control damp-
ers signifi cantly reduce the motions in a wind turbine tower with possible design,
maintenance and operational benefi ts.
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