Iterative Learning Control for Improved Aerodynamic Load Performance of Wind Turbines With Smart Rotors

Currently, there is significant research into the inclusion of smart devices in wind turbine rotor blades, with the aim, in conjunction with collective and individual pitch control, of improving the aerodynamic performance of the rotors. The main objective is to reduce fatigue loads, although mitigating the effects of extreme loads is also of interest. The aerodynamic loads on a wind turbine blade have periodic and nonperiodic components, and the nature of these strongly suggests the application of iterative learning control. This paper employs a simple computational fluid dynamics model to represent flow past an airfoil and uses this to undertake a detailed investigation into the level of control possible by, as in other areas, combining iterative learning control with classical control action with emphasis on how performance can be effectively measured.