Passive and semi-active control of an offshore floating wind turbine using a tuned liquid column damper

Abstract : Offshore floating wind turbines seem a promising technology to harvest wind energy in deep waters. In order to be economically viable it requires mitigating the mechanical loads induced by the waves. This paper shows that the tuned liquid column damper (TLCD) technology, currently employed in naval engineering can be of great relevance to address this issue, if combined with a control strategy. The control strategy consists in adapting the damping coefficient of the TLCD in real time. The performance obtained with the optimal constant damping coefficient serves as a reference to assess the possible improvements brought by active technologies. Simulation conducted in this article report a 39% reduction of the pitch oscillations on a typical 5000 tonnes barge excited by a JONSWAP irregular wave.