Seismic Collapse And Wind-induced Fatigue Analysis Of Wind Turbine Tower

Wind turbine tower is the main part of the whole wind turbine,which is subjected to wind load all the year round,and may also be affected by random seismic load.The effect of wind load is long-term and time-varying,and the earthquake load is random and sudden.The long-term effect of wind load will cause the structure to yield failure due to the accumulation of fatigue damage.The sudden attack of the earthquake action will cause the wind turbine tower to have huge deformation and cause the collapse.Therefore,seismic collapse analysis and wind induced fatigue analysis of wind turbine tower are of great social significance.In this paper,a wind turbine with a hub height of 60 m is taken as the research object.The random wind load of the wind turbine unit is numerically simulated.Two seismic wave sets of near field and far field earthquake are used as seismic load input.ABAQUS finite element software is used to model the tower and blade coupling structure,and the analysis tower is analyzed.The dynamic response of the tower under the interaction of wind and earthquake is studied,and the collapse characteristics of the tower under the high intensity earthquake are studied,and the wind induced fatigue life of the tower under the effect of long wind load is estimated.In this paper,by comparing the experimental results with the static Pushover analysis of a small tube tower,it is proved that the nonlinear finite element model of this paper can accurately simulate the stress characteristics of the tower,and the modal analysis of the tower is carried out,and the order form and natural frequency of the wind turbine unit can be grasps.Then,the numerical simulation of wind load is carried out according to the harmonic synthesis method.The dynamic response of the tower under the wind load alone and under the coupling of near and far field and transient wind loads is analyzed by the ABAQUS finite element software.It is found that the response of the tower to the top of the tower is smaller under the wind load and the rare earthquake load.The wind turbine has good seismic characteristics.Then the collapse characteristics of the windturbine tower are studied by increasing the acceleration of the ground motion.It is found that the weak part of the wind turbine tower is about 5m at the bottom of the tower at the bottom of the tower,which is the same as the yield part of the Pushover analysis.Finally,the rain flow method is used to calculate the linear cumulative damage of the wind turbine tower.According to the S-N curve,the fatigue damage of the tower is obtained,and the fatigue life of the tower is calculated under normal use,and the residual life of the tower is estimated.The fatigue analysis results show that the fatigue life of the wind turbine tower meets the design requirements.