Conceptual Design And Dynamic Analysis Of A Novel Passive Floating Offshore Wind Turbine Structure

With the rapid development of new energy in the world,the development of floating offshore wind turbines has received more and more attention.Although the floating offshore wind turbine has many advantages,its natural environment is very harsh and its floating characteristics are not fixed,resulting in a large vibration response.Therefore,the floating offshore wind turbine is unstable and prone to failure,so it is very important to effectively reduce the vibration of the floating wind turbine.At present,the focus of offshore wind power research is how the design engineer selects the damping device and applies it to the offshore structure reasonably and effectively to minimize its vibration.In this paper,the damping device of spar type floating wind turbine is designed by theoretical derivation and finite element solution.The main contents and conclusions are as follows:This paper proposes a new passively controlled floating offshore wind turbine structure.Firstly,a preliminary three-dimensional dynamic model is established by using the Hamiltonian principle.The large rotation angle problem(geometric nonlinearity)is considered in the dynamic model.At the same time,the tower is regarded as a flexible structure,and a new passively controlled floating sea is derived.The equation of motion of a wind turbine structure(a system of nonlinear equations containing 13 equations).It solves the problems that the TMD quality and motion space of the floating offshore wind turbine are limited(the damping effect is limited),the theoretical derivation is a twodimensional mechanical model,the basic assumption is a small corner,and the tower is a rigid body.The feasibility of the model built by ABAQUS is verified by comparing ABAQUS finite element modeling with experimental data.Then using ABAQUS to solve the dynamic response of the preliminary mechanical model,it is found that the damping effect is obvious.After analyzing the reasons,the preliminary mechanical model was improved,and then the influence of a series of parameters of the new passively controlled floating offshore wind turbine structure on the vibration reduction effect was analyzed.The quality of the designed cylindrical ring and the cylindrical ring were found.The position of the floating center has a great influence on the vibration damping effect.And the law of damping effect changes with parameters is summarized.When the values of k and c increase from small to small,the damping effects of roll and pitch both increase first and then decrease,and find out The best k,c design value.Compared with the vibration damping effect of the internal wind turbine TMD method,it is found that the vibration control effect of the design scheme has a great improvement compared with the control effect of the previous control scheme.This makes it possible to stabilize the spar type floating offshore wind turbine in an extreme load environment.