The Load Spectrum Of A Wind Turbine And The Performance Analysis Of Key Connectors

In recent years,with the rapid development of the wind power generation industry,the power and structure of wind turbines have become increasingly large and complex,and the safe and effective operation of wind turbines has become a research focus of research institutions and enterprises.Aiming at the possible collapse of the wind turbine,from the perspective of bolted flange connection of the tower,the working performance analysis of the original design was performed,and a variable parameter analysis study was carried out in combination with the new bolt material.In this paper,a 6MW wind turbine is taken as an example.Based on the wind turbine design theory such as leaf element-momentum theory,a complete wind turbine generator model is established through the GH Bladed software platform.According to the IEC61400 standard,the typical working conditions that a wind turbine may face during its service life are studied.The aerodynamic performance of the wind turbine is studied,and the blade and tower load distribution is obtained.The static strength analysis,fatigue analysis,modal analysis,and buckling analysis of the tower were performed to verify the reliability of the tower work and to obtain the weak position of the tower under the limit load.Considering the bolted connection between tower sections,weak flange bolted cross sections may be dangerous;considering the installation and processing technology of bolted connections,based on the VDI2230 standard,the flange bolt connection was analyzed for yield resistance,fatigue resistance,crush resistance,shear resistance,and slip resistance.Considering the nonlinear contact of bolted connections,combined with VDI2230 standard and finite element technology,an effective finite element model is established,and various working performance indicators of bolts and connection status of flange joint surfaces are analyzed.Combined with the new class 12.9 bolt material,the variable parameter analysis was performed on the bolt connection from the angle of bolt diameter,number of bolts,and bolt pre-tightening force,and new bolt connection parameters were determined.