| Wind resources known as the "anthracite blue",which is an inexhaustible of new renewable energy.It will not produce any pollution.With the large-scale horizontal axis wind turbine capacity to 10MW in single-level,the hight of tower attach to 120m,the role of the tower's wind load variability and randomness of the cross will become more evident,therefore, the analysis of tower for structural dynamics is one of the important basic research.Wind turbine tower is the main load-bearing parts,impact on the stability and the whole crew performance directly.In this paper,an analysis of wind power at home and abroad at this stage of the development of technologies and trends on the basis of the actuator plate to introduce the concept and theory of pituitrin to MW-class wind turbine based on limit load of the tower,such as changes in the conditions the static strength,fatigue and dynamic response were studied.Mechanical analysis using ANSYS software,large-scale wind turbine on the cylindrical tower of the numerical simulation of the dynamic design for the tower provides a theoretical basis.Through simulation of the tower main conclusions are listed as follows:1) In wind pressure and wind shear generated by random perturbations under a tower of the static strength analysis,inspection of the tower in a variety of load cases is in excess of the maximum stress allowable material stress,whether or not to meet the static strength requirements.Circumstances limit the force of the tower is the focus of the analysis of static strength,which determines whether the wind turbine can be a long cycle,safe operation,the impact of wind turbine is the key to life.2) Tower-based analysis of the static strength,fatigue tower to find the danger point,the danger point by studying the case of fatigue,to measure the fatigue status of the entire tower, through fatigue analysis module of ANSYS to verify the service life of wind turbine tower situation,in line with the design of wind turbine tower life,to meet the requirements of the fatigue life.3) According to the theory of multimodal analysis,mathematical modeling and simulatiom of vibrational mode were conducted for the tower of horizontal axis wind turbine.Numerical evaluation of the tower was performed by using matrix iteration method and the mechanical characteristics of the tower were obtained.It was shown by the first-order innate frequency of the tower was higher than blade passing frequecy(BPF),meaning that the tower was a rigid one and its resonance might be caused by the stimulation of wind wheel would not take place.According to vibration theory,the energy of tower vibration was focused at the first-and second-order frequency on it's the vibration mode,showing that the shimmy was the main tower vibration mode which was the main reson of tower fatigue. 4) The use of ANSYS software module to optimize the design to the drum tower for the design of variable wall thickness to the material allowable stress for the bound volume of the tower in the objective function for the optimized design,the end cylindrical tower wall the optimal value.And verify that the tower has been optimized to meet the static strength,modal analysis,fatigue strength and buckling strength of the safety performance of the optimization for the tower has laid a theoretical basis.Studies have shown that on the wind turbine tower vibration affecting the stability of wind turbine performance and the whole key study on the basis of fan problems.
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