Seismic response analyses of a wind turbine under operating conditions considering soil-structure interaction

A detailed three-dimensional finite element model including soil-structure interaction was developed for a 1.5 MW onshore wind turbine. A comparative study was performed to investigate the soil-structure interaction (SSI) effects on the seismic responses of the wind turbine under operating conditions. Wind speed time histories were converted to wind load time histories under the operating condition by using the FAST program. Simulation analysis was conducted using the EERA program to derive earthquake excitations at the base of the soil model. Then modal analyses and seismic response analyses were performed. The results show that soil-structure interaction has significant influences on the dynamic characteristics of the wind turbine tower, which results in amplification of the structural responses.