Implementation of the ‘smart’ rotor concept - Wind Power Generation and Wind Turbine Design - page 501

for the easy assembly of multi-component designs. In addition, TPCs are to be
preferred for deformable surfaces because many are tougher than thermosets.
Finally it was mentioned that a rib-spar design is also the optimal topology for
transferring loads through the blade.

6.4 Control issues

Load alleviation experiments at the TU Delft, using strain measurements as a feed-
back signal have shown that a signifi cant reduction of the fatigue loads is possible.
But many other signals, including infl ow measurements are possible. Measuring
the infl ow could increase the load alleviation performance of any control system
because then the largest source of fl uctuating loads is known and feedforward
control can be applied to it.
However, before aerodynamic load control on wind turbines can become a real-
ity many hurdles have to be taken. Although the 'smart' structures from aerospace
pose an interesting benchmark, the demands for wind turbines are different. Sec-
ondly, there has been a large effort into aero-servo-elastic modeling over the last
few years, but the structural implementation of the spanwise distributed devices
has been relatively ignored. Here some light on the matter has been shed, as well
as on some of the control issues involved.

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