Optimal design of semiactive MR‐TLCD for along‐wind vibration control of horizontal axis wind turbine tower.

Summary: Present study aims to address the design of smart vibration control scheme for horizontal axis wind turbine tower using magneto‐rheological tuned liquid column damper. With this in view, a reduced order model of the blade‐tower system is used, considering centrifugal stiffening and gravitational effects that lead to time‐dependent dynamic stiffness matrix. Aerodynamic load on the blades is modeled using blade element momentum theory. Semiactive control law in linear quadratic regulator framework is developed to mitigate the along‐wind vibration of the tower. To implement the control law, multiblade coordinate transformation is adopted that converts the system matrices in the nonrotating framework to tackle its time dependency. The performance of the proposed control algorithm is demonstrated using numerical simulations with and without controller. Clipped optimality of the control force is imposed to keep the parameters of magneto‐rheological tuned liquid column damper in the feasible range. Finally, sensitivity analysis is carried out to demonstrate the performance envelope of the proposed control algorithm for different operational scenario. Results presented in this paper clearly demonstrate that the proposed algorithm can be employed for effective along‐wind vibration control of large HWAT tower. [ABSTRACT FROM AUTHOR]