Dynamic Response Analysis For Offshore Bucket Foundation And Wind Turbine Structure System

Wind load and wave load are the major loads of offshore wind turbine structure suffered from environments. Thus determining the wind load and wave load reasonably are the basis for stress analysis of the structure. The wind load acting on the tower and the wave load acting on the transition section of bucket foundation will produce relatively large stress. At the same time due to the random characteristic of wind load and wave load, the bucket foundation and tower will generate vibration. Analyzing the dynamic feature and dynamic response under these two loads of the turbine structure of bucket foundation is an important part of the safety assessment and also have important reference value and significance of engineering for guiding the design of bucket foundation and tower.In this paper, according to conditions where the structure of wind power installed and the characteristics of random wind load, the tower is divided into 14 segments, and wind load time-history of 14 positions are simulated based on harmonic superposition method .The connection between bucket foundation and tower is equivalent to the large diameter cylinder, using linear wave theory analog random waves based on the measured wave height and period, combined with the role of diffraction theory to derive the wave force acting on the large-scale structure. In this paper, using the finite element software ABAQUS to establish the bucket foundation and turbine structure modal of 3-megawatt and introducing finite element model of the structure and the boundary conditions of the model in detail. The vibration characteristic of the structure was analyzed by the modal analysis of the bucket foundation and turbine structure. And based on the modal analysis, the dynamic implicit analysis module was used to further analyze the dynamic response of the structure under wind load alone and wave load alone. Making different combinations of wind load and wave load and calculating the dynamic response of the structure under different combinations. Through the analysis of the dynamic response under various load combinations, the wind and wave peak combination is determined as the control condition.In summary, this paper major analyzes the dynamic response of the bucket foundation and turbine under wind load and wave load. And some reference value engineering analysis conclusions for the design of the offshore bucket foundation and turbine in the complex marine environment is provided.