為實現2050年淨零碳排放目標並減少全球對化石燃料的依賴，再生能源的發展成為全球的重要議題。近年來，再生能源迅速發展，離岸風力發電成為台灣最有競爭力和潛力的綠色能源之一。國內的離岸風電逐漸由近岸的固定式轉向深水域的浮動式離岸風機。然而，浮動式風機面臨風、波、流等環境載重帶來的平台晃動問題，影響發電效率、平台穩定性和安全性。本研究的目標在於設計浮動式平台，參考TetraSpar的被動式減振技術，透過下部懸吊系統來抑制浮台在長週期波浪載重下引起的振動，從而提升浮台的安全性、穩定性和風機的發電效率。
本研究選定場址於新竹外海，參考各傳統浮台種類特性，根據水深條件，進行浮台選型。鑒於淺水條件以及設計成熟度選擇駁船式平台，但由於駁船式浮台俯仰方向之自然週期容易與波浪週期共振，因此採用下部懸吊系統增長俯仰方向之自然週期，以避免平台共振而提升穩定度。
本研究以改良式八邊形駁船式平台搭載NREL-5MW離岸風力機作為分析對象，先以SolidWorks進行平台物理參數計算建模，再由Ansys AQWA進行頻域水動力計算，匯入Orcina OrcaFlex進行時域動態分析。
本文分析著重於下部懸吊系統優化配置，分為優化下部懸吊系統與挪威船級社(DNV)規範檢驗。優化下部懸吊系統藉由規則波計算反應振幅因子(RAO)得出優化之下部懸吊系統配置與掛載之幾何形狀；挪威船級社規範檢驗以極限限度狀態(ULS)、意外限度狀態(ALS)、可運轉限度狀態(SLS)及疲勞限度狀態(FLS)進行規範檢驗。其中檢驗項目包含風機停機與運轉時之浮台姿態、繫纜張力與懸吊系統張力，並針對有下部懸吊系統之配置與無下部懸吊系統之配置進行比較。
綜觀本文之研究，可分為浮台設計和被動式減振技術優化兩方面。浮台設計概念有望指引未來實際海域浮動式平台的設計方向；而被動式減振技術則減少主動式壓艙控制的使用，從而降低運維期間的維護成本。透過被動式減振技術提高浮台的穩定性，有望減少浮台在極端條件下翻覆的風險，同時提高運轉狀態下的發電效率，增加浮動式風機商業化的可行性，成為未來國內具有競爭力的再生能源。

To achieve the 2050 net-zero carbon emission goal and diminish global reliance on fossil fuels, the development of renewable energy has emerged as a crucial global concern. Recently, offshore wind power has swiftly progressed, establishing itself as one of Taiwan's most competitive and promising green energy sources. The domestic offshore wind power sector is transitioning from nearshore fixed installations to deep-sea floating turbines. However, floating wind faces challenges such as platform oscillations caused by environmental loads, impacting power generation efficiency, platform stability, and safety. This study aims to design a floating platform inspired by TetraSpar's passive control technology, using a counterweight suspension system to suppress vibrations induced by long-period wave loading, thereby enhancing platform safety, stability, and wind turbine power generation efficiency.
The selected site for this study is offshore from Hsinchu, Taiwan. Traditional floating platform characteristics were considered based on water depth conditions, leading to the selection of a barge-type platform due to shallow water and design maturity. To address pitch resonance issues, a counterweight suspension system was adopted to extend the pitch natural period, mitigating platform resonance and improving stability.
The research focuses on an improved octagonal barge-type platform carrying the NREL-5MW offshore wind turbine. The study utilizes SolidWorks for physical parameter modeling, Ansys AQWA for frequency-domain hydrodynamic calculations, and Orcina OrcaFlex for time-domain dynamic analysis.
The paper emphasizes the optimization of the counterweight suspension system and compliance with Det Norske Veritas (DNV) classification society regulations. The optimization involves calculating the Response Amplitude Operator (RAO) through regular wave analysis to determine the optimal configuration and geometry for the counterweight suspension system. DNV compliance checks include Ultimate Limit State (ULS), Accidental Limit State (ALS), Serviceability Limit State (SLS), and Fatigue Limit State (FLS). Inspection items encompass platform attitudes during wind turbine shutdown and operation, mooring line tension, and suspension system tension. Comparisons are made between configurations with and without a counterweight suspension system.
In summary, the study focuses on platform design and passive control technology optimization. The advancements in platform design are expected to guide future practical offshore floating platform designs. The utilization of passive control technology reduces reliance on active control, lowering maintenance costs during operations. By enhancing platform stability using passive control technology, the study aims to reduce the risk of platform overturning under extreme conditions, increase power generation efficiency during operation, and enhance the commercial viability of floating wind, making it a competitive renewable energy source in the future domestic market.

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