本研究為了評估海上浮動式風機拖帶作業系統的穩定性及安全性，本文發展出一套結合拖船、拖纜及浮式風機耦合拖帶運動數值模擬分析工具，文中利用一套結合耐海性與操縱性的非線性六度運動數學模式，並透過四階Runge-Kutta數值方法來模擬計算船隻在海上執行拖帶作業時的時程領域運動反應。
然而，作為一個高層結構，浮式風機在進行拖帶任務時，在風、浪、流的影響之下可能會引起較大的傾覆力矩，而拖纜張力在拖帶過程中也對浮式風機的穩定性產生一定的影響，在各種力及力矩的作用下，船隻航行的航向穩定性與靜水中相差甚遠，因此，在文中加入了輔助拖船的想法，利用PD控制器來模擬控制拖船之角度，藉由拖曳角度的改變而產生不同的分力作用於浮式風機平台上，改善在進行拖帶任務時浮式風機因海況而產生的運動反應，並且達到航向之控制。
本文考慮在風浪中包含規則波與不規則波，以不同波向並且加入各種環境負載的情況下，探討拖帶速度、有無輔助拖船等要素對拖帶系統航向穩定性的影響以及對浮式風機的運動狀態進行分析，以了解這些條件對於整個拖帶系統的影響。將上述各種計算環境負載的數學模型，集合成一套多船船體運動數值模擬分析工具。利用此工具之模擬分析結果，為浮式風機拖帶作業提供了初步的安全性評估。

This study aims to assess the stability and safety of an offshore floating wind turbine towing operation. The paper presents a numerical simulation analysis tool that combines a tugboat, towing cable, and the dynamics of a floating wind turbine during towing. The study utilizes a nonlinear six-degree-of-freedom mathematical model, which integrates both seakeeping and maneuvering characteristics. The vessel's towing motion response during the towing operation is simulated and computed using a fourth-order Runge-Kutta numerical method.

However, as a high-level structure, the floating wind turbine may experience significant overturning moments under the influence of wind, waves, and currents during the towing operation. The tension in the towing cable also affects the stability of the floating wind turbine during towing. Under various forces and moments, the vessel's course stability differs significantly from the static conditions in calm water. Therefore, the idea of incorporating an auxiliary tugboat with a PD controller to control the tugboat's angle is introduced in the paper. By adjusting the towing angle, different forces are generated on the floating wind turbine platform, improving the motion response of the floating wind turbine under varying sea conditions.

The study considers regular and irregular waves, as well as different wave directions and various environmental loads, to investigate the influence of towing speed and the presence of an auxiliary tugboat on the towing system's course stability and the motion of the floating wind turbine. These mathematical models for various environmental loads are integrated into a multi-vessel motion numerical simulation analysis tool. The goal is to provide a preliminary safety assessment for the floating wind turbine towing operation by the simulation results obtained with this tool.

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