本研究以NEMOH與WEC-SIM電腦程式為基礎探討OC3-Hywind風機在波浪作用下之動態響應模擬，其中邊界元素法是依據線性繞射理論(Linear Diffraction Theory)求解繞射/輻射問題(Diffraction / Radiation Problem)，並考慮Cummins Time-Domain Equation作為建立時程領域求解器。
為了比較離岸風機作業海域之波浪環境與水深影響，在此利用反應振幅因子(Response Amplitude Operator, 簡稱RAO)來估算出在不同波浪環境下風機的運動反應。由於RAO的峰值處即代表風機與波浪的共振週期，且直接影響風力發電機的穩定度與安全性。因此藉由探討共振情況下的受力情形，即可知道風機運動所產生之錨鏈力對於風機之影響，結果可提供設計風機錨鏈系統之參考依據。而為了避免風機產生過大的運動量，錨鏈系統是以準靜態模式(Quasci-Static State)來估算繫纜對於風機動態的限制作用，最後比較各類程式對於OC3-Hywind風機在極端條件下(如暴風)之模擬結果。
在本研究中，模組化設計系統由於具有實驗設計(Design of Experiment)之優點，在結合不同尺寸、外型、搭載之錨鏈系統後，將可探討在不同海況條件下，浮式風機在單一自由度或多個自由度耦合下之運動反應。

This study studies the real-time motion responses of OC3-Hywind spar floating platform in waves based on the modular design system, composed of NEMOH and WEC-SIM. In the time-domain simulation, both of the radiation and the diffraction method are used to obtain the hydrodynamic forces from frequency-domain Boundary Element Method (BEM) solver. In order to simulate the system dynamics of OC3-Hywind spar floating platform, the Cummins time-domain equation is adopted by solving the governing equations in 3 Degrees-of-Freedom (DOF) motions, including surge, heave, pitch. Besides, an indicator, Response Amplitude Operator (RAO), is considered to realize the resonance period of OC3-Hywind spar floating platform by performing regular wave simulations at various frequencies. Since the RAO peak corresponds to the resonance period of OC3-Hywind spar floating platform, it would be considered as a predominant parameter relating to the designs of safety and stability, and it can be used to estimate the floating platform’s response to waves in case of the mooring system. Subsequently, the results present that the quasi-static mooring system is applicable to the estimation of mooring forces as well as the restriction of the floating platform in motion responses. By comparing our model results with other published results of OC3-Hywind spar floating platform, it is verified that the calculation of motion responses is reliable. Eventually, this study would provide a modular calculation process and help realize hydrodynamic characteristic of wind float’s platform in engineering practice.

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