Modelling and attitude control of a shrouded floating offshore wind turbine with hinged structure in extreme conditions

This paper addresses the modeling and attitude control of a novel shrouded floating wind turbine with hinged structure in harsh environmental conditions. Firstly, SimMechanics™ is applied to model the mechanical components of the wind turbine system. Secondly, the wave- and wind-loads acting on the system are respectively calculated based on Morison's equation and blade element momentum theory. Controllers of the elevator and the rudder located at the upwind side are designed based on linearized models to enhance the stability of the system. Numerical examples with three extreme weather conditions are finally performed to verify the effectiveness of the controllers. The results demonstrate that the pitching motion of the nacelle can be regulated to be within 3 degrees in the examples. In addition, the wind turbine could yaw itself stably toward the wind direction.