Reliability-based calibration of site-specific design typhoon wind and wave loads for wind turbine

Abstract

The wind turbines (WTs) that are designed, constructed, and installed near the coastline of mainland China are faced with geographically varying tropical cyclone hazards; failure of WTs due to the tropical cyclone (TC) hazards has been observed in this considered region. The reliability-based Chinese design code calibration of WTs subjected to TC hazards for the considered region seems missing in the literature. In the present study, we calibrate the site-specific design TC wind and wave loads for designing offshore and onshore WTs located in the considered region for selected target reliability indices. The calibration considers the correlated TC wind speed and significant wave height during the passage of TC events. Also, the companion load factors by considering wind load and inertial wave load effects are calibrated. Moreover, the statistics of the responses of the onshore and offshore versions of the National Renewable Energy Laboratory 5 MW wind turbines are calculated using the software package FAST. The statistics of the responses are used in the reliability-based verification analysis by considering the calibrated design TC wind load and wave load requirements. The results indicated that using the calibrated geographically varying TC wind and wave loads is adequate and can be used to aid structural design code making.