Modeling and vibration control of a coupled floating wind turbine system

This paper presents the dynamic modeling and vibration control design of a floating wind turbine system. Two flexible mooring lines attached to a flexible wind turbine tower (taut-moored floating spar) are used to represent the dynamics of system. The wind turbine tower is modeled as an Euler-Bernoulli beam, and the mooring lines are modeled as two strings. The control laws are designed to suppress vibrations of both wind turbine tower and the mooring lines. Based on the construction of a physically motivated Lyapunov function, the bounded stability is proved with the proposed control. Numerical examples illustrate the performance of the control system.