近年來，於各國提倡綠色能源的背景下，離岸風電隨之問世，由於固定式離岸風
電受限於水深及地形上的限制，如欲獲得更多的風能，勢必仰賴浮動式平台以克服水
深的議題。目前國外使用之浮動式風力發電主要倚靠懸垂式繫纜系統將浮動平台繫泊
於一定的範圍，周圍海域的航道安全性乃屬重大議題之一，於設計初期必考慮其漂移
對於船隻航道的影響。如發生繫纜失效對於整體結構物的運動響應變化為謹慎評估分
析建置浮動式平台不可忽視的其中一環。台灣海峽每年頻頻遭受颱風及東北季風的侵
襲，且西部海域 50~100 米水深為適用浮動式平台之處，屬淺水水域，相較深水的懸
垂式繫纜，於淺水下更易使繫纜產生極大的張力而提升失效的機率。
本研究目標場址為新竹外海，使用駁船式平台搭載 NREL 5-MW 風機，繫纜系統則
選用懸垂式。透過 OrcaFlex 數值模擬及水工模型 1:64 縮尺實驗分析浮動式平台於極
端海況下，繫纜失效後之剩餘繫纜張力、平台姿態及漂移變化。本研究先行考慮平台
於規則波、純流、純風的作用下，初步探討繫纜失效後的趨勢，隨即進入本研究的重
點，平台於 10 年、50 年回歸期的波浪條件及不同角度的 50 年回歸期的風作用下，
繫纜失效後整體之運動行為。本研究中的模擬和實驗結果均呈現平台於繫纜失效後，
在位移自由度上，surge 和 sway 受到較大的影響，而 heave 變化不大；在旋轉自由
度上，當波浪和風向不平行時，roll 和 yaw 的影響比較顯著，而 pitch 則變化不大。
針對繫纜部分，則是取決於平台失去繫纜的位置而影響了剩餘的繫纜張力變化，由於
繫纜失效後平台將有明顯的 yaw 轉動，使風機受風面積不斷變化，容易產生不穩定的
風推力，導致繫纜張力上升。當波浪與風的方向相同或是風的方向與繫纜失效的位置
相同時，將造成平台明顯的漂移。一條繫纜失效後無可避免第二條繫纜接連失效的風
險，為觀察更細微之物理現象及連續斷纜後的穩定運動，本研究利用縮尺試驗分析平
台於規則波、純流、純風條件下，繫纜連續失效後的運動行為。最後比較正常條件、
單條斷纜及連續斷纜下，風波流各別對於平台之作用行為。本研究之研究成果除可比
較繫纜失效前後之平台穩度及漂移範圍差異，亦可提供未來分析浮動式風場中空間運
用與航道安全之議題。

Currently, the floating offshore wind power used in foreign countries mainly relies on the catenary mooring system to moor the floating platform in a particular range. The safety of navigation in the surrounding sea area is one of the major issues. In the early design stage, the impact of drift on navigation must be considered. If the mooring line fails, the change of the motion response of the whole structure is one of the links that cannot be ignored in the construction of the floating platform in careful evaluation and analysis. The Taiwan Strait is
frequently attacked by typhoons and the northeast monsoon every year, and the water depth of 50-100 meters in the western sea area is suitable for floating platforms. However, it generates extreme tension and increases the chance of failure in the mooring lines.The target site of this study is the sea of Hsinchu. The barge-type platform carries the NREL 5-MW wind turbine, and the mooring system adopts the catenary type. This study is verified by OrcaFlex numerical simulation and a 1:64 scaled model experiment. First, considers the platform under the regular waves, only currents, and only winds. Then analyze the motion response of the platform after the mooring line failed under the wave conditions of 10-year
and 50-year return period with the different directions of winds in the 50-year return period.The simulation and experimental results in this study both show that after the mooring fails, the surge and sway are significantly affected in the displacement degrees of freedom, while heave changes little; in the rotational degrees of freedom, when the wave and wind directions are not parallel, the effects of roll and yaw are more significant, while pitch does not change much. When the wave is in the same direction as the wind or the wind is in the same direction as the location where the mooring line failed, a significant drift of the platform will result. After one line's failure, the second line failure risk cannot be avoided; this study uses a scaled-down experiment to analyze the platform motion under the regular waves, only currents and only winds. Finally, compare the behaviors of the waves, currents, and winds on the platform under intact state, one line failed state, and continuous lines failed state. The results of this study can compare the differences in platform stability and drift range before and after the failure of the mooring line, which provides future analysis on the issues of space utilization and navigation safety in floating wind farms.

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