Robert Unguran

TL;DR: The proposed feedback-feedforward controller ensures robust stability and performance and achieves better load reduction than a classical integrator-based feedback controller combined with inversion-based feedforward controller.

Abstract: In order to reduce the “cost of energy” for wind turbines it is an ongoing trend to increase the rotor diameter, which increases fatigue loads in the blade root area. Thus, a critical prerequisite for increased rotor diameter is the reduction of loads, which can be utilized by passive and active measures. This paper is giving an overview of current research work towards the use of a flexible trailing edge for load reduction as it is being pursued in the German national SmartBlades project. The active trailing edge is designed to change the lift of the outer blade in a way to counteract sudden changes caused by gusts or wind shear. Areas that are covered include the simulation towards the load reduction potential of such flexible trailing edges, the structural design of the trailing edge itself as a compliant mechanism, its experimental validation and fatigue investigation as well as multistable approaches for the design of such trailing edge flaps.

TL;DR: In this paper, the authors present a method to easily determine blade-mounted lidar parameters, such as focus distance, telescope position, and orientation on the blade, to provide a preview of inflow wind speed that can be used as a feed forward control input for the mitigation of such periodic blade loads.