초록 열기/닫기 버튼
As the reliability of a tripod support structure with suction buckets should be evaluated by avoiding resonance, an efficient method to predict natural frequency, which is also known as an effective tool to show the existence of damage in wind turbines, is suggested. The whole structure is modeled by beam elements, while a nacelle with blades is considered as a mass. A boundary condition of the suction buckets is described by a serial combination of stiffness elements for soil and a connecting part of a suction bucket. Then, an effective structural health monitoring (SHM) system is developed to validate the proposed modelling method. Accelerometers, strain gauge and various sensors for measurement of sea environment are installed in proper locations, and measured natural frequency is extracted by measured bending strain. It is validated that the measured natural frequency is the almost the same as the predicted one, with an error rate below 1%, and the natural frequency has sufficient margin to major excitation frequencies such as 1P and 3P. Also, it is observed that the measured natural frequency is constant for 3 months.
키워드열기/닫기 버튼
Offshore Wind Turbine, Suction Bucket, Natural Frequency, Structural Health Monitoring
