由於台灣西部海岸之離岸風場歷經示範獎勵、潛力場址、區塊開發3.1期選商之後，近岸之固定式風場已趨近飽和，為因應浮式風場將做為後續之開發重點，本研究旨在探討適用於台灣新竹海域之動態電纜配置型式，並以15 MW 風機及半潛式浮台作為目標機組。研究流程先是進行動態電纜長度與水深比例之分析，得出同時兼具技術及成本可行性之電纜長度約為水深之3倍。以此為基礎，除了設計常見的懸垂式（Catenary）及緩波型（Lazy Wave）電纜外，亦加入雙波型(Double wave)電纜進行分析，透過電纜長度及浮球段總長度之統一，進行電纜張力及曲率之分析並以此進行電纜疲勞計算，預估各種型式在台灣海域下之使用年限，並探討浮球排列對於電纜動態響應之影響，進而提供後續浮式風場之設計參考。
除動態電纜配置以外，本研究內容亦包含浮式機組水下基礎設計流程，包含浮台擇定、繫纜設計、錨碇選型等。此外，由於長期海氣象資料通常難以取得或所費不貲，如浮標、光達、海氣象觀測塔等，加以這些觀測資料多位於離岸較近之海域，觀測數據可能受海陸交界影響而難以真實反映距岸較遠之浮式風場，故本研究加入歐洲中期天氣預報中心的第五代全球大氣再分析資料來做為風機運轉條件下之環境參數，以(25.0°N, 120.5°E)為代表點位並統計2013-2022十年長期平均下每月之風與波浪資料，並以此作為電纜疲勞之荷載試次，然再分析資料缺乏流速數據，故再海流方面則以新竹浮標流速進行風波流耦合試次。
最後則以適應度參數來比較五個設計方案之表現，透過正規化張力、正規化曲率、及正規化預估年限加總作為設計方案之適應度參數，以涵蓋各設計方案對於極端條件以及常態運轉條件之適用性。結果顯示以方案四為最佳，證明雙波型電纜具有其研究價值，且將浮球段設計於較低位置可有效減緩觸地點之疲勞累積。
以下將針對各章節進行重點摘錄及簡要介紹:
第一章 前言
由於浮動式基礎在水深大於60 米後之建造成本相較固定式基礎逐漸取得優勢，且台灣離岸風場淺水區域已趨於飽和，故浮動式風場之開發指日可待。根據統計指出，高達83.2%之風場保險索賠皆來自於電纜，且浮式風機之動態電纜更需長期暴露於海洋中，因此需要在設計階段做更審慎之考量。 因應大型化風機趨勢，本次研究選擇單機容量15 MW作為目標風機，在浮台部分則考慮台灣水深及波浪週期選擇半潛式平台，繫纜系統則採用3*1懸鏈設計並搭配拖曳錨作為錨碇型式，以新竹外海100 米水深作為目標場址並設計5種電纜方案包含懸垂式、緩波式以及雙波式來進行評析。 
第二章 研究方法
本次研究主要以數值軟體Ansys AQWA 及 Orcina Orcaflex進行模擬分析，兩套軟體皆以勢流理論為基礎，假設流體不可壓縮、無黏性且無旋流。惟因Orcaflex 無法進行流體輻射、繞射計算，故需先在AQWA進行水動力參數計算並將結果匯入Orcaflex，並搭配繫纜與電纜等小結構物進行時域上計算。在電纜及繫纜之模擬則將之視為小結構物並以莫里森方程式（Morison's equation）進行計算，電纜及繫纜視為數個線段與節點組成，並以質量堆積法（Lumped Mass Method）加以計算。
疲勞部分則將整條電纜視為均勻銅導體，將電纜之張力及曲率時序列轉變為應變時序列，以雨流計數法得出每個節點經歷的應變範圍及循環次數，帶入應變循環曲線（ ε-N curve ）即可得出在單一試次下累積之疲勞損傷，換算各試次於全年所佔之機率分佈並以Miner’s Rule進行線性疊加，即可得出電纜一年之累積疲勞值，將疲勞損傷值倒數即為預估之電纜生存年限。
第三章 數值模擬設定
在環境條件部分，主要分為極限限度條件（ULS）及疲勞限度條件（FLS）來進行資料蒐集，極端條件部分以國內對於新竹外海極端海況相關文獻作為依據，而疲勞條件則以ERA5再分析資料並以月為單位做長期平均，以了解台灣在不同季節及季風轉換下之不同風波流入射角度所造成影響。
機組部分則以緬因大學設計之Volturn US-S 半潛式平台作為浮台，搭載國際能源署於IEA Wind TCP Task 37所發表之15MW風機，繫纜部分則以直徑160 mm無檔鐵鍊基於懸鍊理論進行繫纜設計。在電纜部分以動態段長度為水深三倍為基礎，設計以下五種電纜型式。
方案一 : 懸垂式，無配備浮球段
方案二 : 緩波型，單一浮球段，浮球段位於相對低處
方案三 : 緩波型，單一浮球段，浮球段位於相對高處
方案四 : 雙波型，浮球段分兩段，第一浮球段位於相對低處
方案五 : 雙波型，浮球段分兩段，第一浮球段位於相對高處
第四章 數值模擬結果
本章節首先進行自由衰減試驗，得出平台於六個自由度之自然週期並與緬因大學之技術報告進行比對以確認建模準確性。接續進行平台與繫纜之設計規範檢核，以確保繫纜設計之可行性，後續在進行電纜數值計算時若有超出電纜材料強度規範時，則需以改良電纜設計或配件為主。
在規則波與不規則波模擬中，由於懸垂式並未配有浮球段，在張力表現上時有超過最小破斷力之情形，故仍建議在動態電纜上配有浮球。然在方案二到五配有浮球型式上，可發現在張力上雙波式表現較佳而曲率則反之，浮球位置又以相對低處比高處表現來的佳。而在疲勞計算上，五種方案皆在觸地點附近有最大損傷，然又以方案四表現最佳，由觸地點張力密度圖中亦可看出方案四張力平均值及標準差皆為最低，故可推測在台灣海域電纜疲勞受張力影響較大。然在適應度參數中仍以方案四為最佳，證明雙波型式可更有效減緩觸地點疲勞，可作為未來動態電纜之設計選項之一。
此外，從每月之電纜張力及曲率結果可發現，以常態運轉來說，雖每年12-1月為東北季風最強勁之季節，但最大張力及曲率則時發生在三月四月及九月十月左右，推測原因與風速及風機之風推力有關，當風速達到額定風速10.59 m/s時會產生最大風推力，並以塔架為力臂產生力矩使機組承受較大之晃動，故當風速落在額定風速附近時，電纜容易有較大之動態響應發生，此現象有別於一般之預期，需在後續浮式機組設計上多加留意。
第五章 結論與建議
綜上所述，由於最大疲勞皆發生於觸地點，故可在觸地點附近安裝抗彎器或拴鏈(Tether)以防止電纜損壞。從本研究亦可觀察出，電纜之動態響應與水深、浮球布置、風推力、平台位移、繫纜設計息息相關。故在設計電纜型式時需因地制宜，並在電纜長度、浮球長度及位置、繫纜設計等因素進行交互調整方能達成最佳設計方案。

In response to the growing need for renewable energy, this study conducts comprehensive research for floating offshore wind turbines and focuses on the optimization of dynamic cable. The site is selected in Hsinchu offshore where the water depth reaches 100 meters. The Volturn US-S semisubmersible platform was equipped with a 15-MW wind turbine published by the International Energy Agency.
The main objective of this study is to optimize the dynamic cable configuration to suit the specific environmental loadings in Taiwan. The newly proposed double wave configuration has been compared with typical catenary and lazy waves, using identical cable length and total buoyancy. Accompanied by adjustments in buoy positioning, a total of five designs were modeled using numerical simulations in Orcina Orcaflex. The research scope includes both the Ultimate Limit State (ULS) and Fatigue Limit State (FLS) to evaluate cable performance under extreme and normal operating conditions.
Additionally, the study determines the optimized ratio between cable length and bathymetry, suggesting that three times the water depth is a suitable parameter considering technical and economic feasibility. Lastly, the application of ERA 5 reanalysis data is involved for the load cases in fatigue analysis. The data has been collected from node (25.0°N, 120.5°E) and spanning 10 years from 2013-2022 which better demonstrates the long-term environmental loadings and the coupled interaction.
As per the simulation results, configurations with buoy exhibit substantial improvement compared to the catenary wave. Specifically, the double wave configurations take advantage of the cable tension, while lazy waves excel in reducing curvature. A relatively lower buoy position proves to be a better solution due to the stronger current in the higher position.
Summarized by the fitness value obtained from the simulations, the double wave configuration with a lower buoy position (Case 4) stands out as the optimal solution among all cases. This finding validates the efficiency of double wave configurations and provides a reference for future floating offshore projects.

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