Comparison of different dynamic models for floating wind turbines

Abstract

There are different approaches utilized to establish dynamic models for floating offshore wind turbines, but their distinction and applicability are often confusing. This paper presents the theories about four different dynamic models developed for simulating floating wind turbines, including a single-rigid-body model, a corrected single-rigid-body model, a multi-rigid-body model, and a multi-rigid-flexible-body model. Subsequently, a series of comparisons between the four dynamic models are conducted to assess their differences and applicability for simulating floating offshore wind turbines. The results show that the multi-rigid-flexible-body model is most accurate but most time-consuming. In most cases, the multi-rigid-body model and the multi-rigid-flexible-body model can be performed, except for the aeroelastic effects and global dynamic responses caused by the vibration of the tower and blades. In contrast, the single-rigid-body model has simpler dynamical methodologies and less computational cost. However, it has some internal limitations, for instance, limited degrees of freedom, neglecting aeroelastic effects, neglecting gyroscopic effects, etc. Hence, the corrected single-rigid-body model is proposed and performs better than the original single-rigid-body model at the cost of a little time-consumption.