本研究主要是利用ANSYS Aqwa分析DeepCwind半潛式浮動式風力發電機在波浪及風的耦合作用下的運動響應。首先，利用流體動力係數作網格獨立性分析以確立最少的網格數，接著分別考慮二階阻尼力及二階波浪激盪力等非線性項對浮式風機的影響。再來，考慮錨鍊系統的影響，將風機分別繫上準靜態及動態錨鍊，觀察兩種錨鍊模型對風機運動響應的影響。另外，波向角及風對於風機運動響應的影響也是本研究的研究項目之一。最後，本研究應用空氣及水動力的耦合分析，模擬風機在斷纜後的運動軌跡。根據斷纜分析的模擬結果，斷纜後的軌跡與對照組相當接近，但是由於風力被低估的緣故，仍然存在一些偏差。

This thesis aims to analyze the motion response of the DeepCwind semisubmersible floating platform in waves based on potential-flow theory by considering the second-order wave excitation force connected by two different types of mooring models at several wave heading angles. In addition, wind as a factor was considered and applied in the analysis of platform motion. Linearized potential-flow diffraction and radiation problems presented by hydrodynamic force in the frequency domain were solved using the three-dimensional panel method. To supplement the nonlinear viscous drag, this study adopted the quadratic damping matrix instead of Morison’s element. In addition, slow-drift force was calculated using quadratic transfer function matrices to simulate wave interaction. The study also investigated the effect of mooring systems on motion responses. The results of the quasi-static mooring model were compared with those of the dynamic mooring model, and the effect of wave heading angles on platform motion was analyzed. Finally, this study applied an aero–hydro simulation for the analysis of the DeepCwind semisubmersible wind turbine when the mooring line broke. The results indicated that the traces of the platform were approximately calculated; however, some deviations remained due to the underestimation of wind.

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