因應未來浮動式風場需求，本研究進行了50公尺與100公尺水深下的浮動式變電站及動態電纜設計。考量到浮動式平台上方可利用之空間大小，決定以駁船式平台作為變電站的載體，並且使用懸垂繫泊系統將平台運動限制於一定範圍內，避免平台隨意漂移造成附近結構物或航道的危險。在動態電纜設計方面使用懸垂式與緩坡(Lazy wave)形式電纜進行設計，避免電纜承受過大張力、曲率或疲勞累積而產生破壞，旨在找出可因應台灣極端海氣象條件下可存活之電纜配置。
本研究藉由AQWA與OrcaFlex兩套數值模擬計算後，在單一環境外力作用下(風、波、流)，純風與純波條件的動態電纜運動是由平台運動所連帶導致，而純流條件則是直接作用在動態電纜上，且發現Lazy wave形式電纜較難抵抗強烈之海流。另外，在不同角度配置下，動態電纜產生破壞的位置也會有所不同，在0度配置下，動態電纜的觸地點容易產生曲率過大的情形；在90度配置時，近海底床上之動態電纜會有較大的位移產生；在180度配置下，動態海纜的S形曲線配置容易消失，無法提供緩衝效果，導致電纜張力瞬間明顯上升。
在不同水深比較下，發現水深100公尺比起50公尺的Lazy wave電纜更容易調適海況負載條件而存活，其原因為100公尺水深的電纜配置有更多的壓縮或拉伸空間。而在50公尺水深下，可將電纜配置於靠近海床處(方案二)或是雙波浪形電纜(方案三)，透過橫向空間來增加電纜運動空間，進而避免電纜受到破壞。
除了使用數值模擬進行研究外，本研究也使用1/42縮尺模型進行浮動式變電站與動態電纜試驗。在不規則波浪作用，動態電纜的頻域能譜表現在實驗與數值模擬比對上有良好之吻合性，可以發現動態電纜觸地點的曲率變化主要以波浪頻率為主導，而在電纜張力頻域能譜表現與浮動式變電站的pitch頻域能譜表現有相同之趨勢，因此可以推測電纜張力的主導應與變電站pitch運動有關。最後本文亦提出一個包括動態電纜張力、曲率以及疲勞之適應度參數作為檢視及探討浮動式變電站動態電纜最適合之配置型態。
透過以上之研究，本文之研究成果除可提供未來浮動式變電站與動態電纜配置的基礎運動行為之研析基礎，並可進一步了解其可能產生的電纜破壞區域，將可作為我國未來相關浮動式變電站或浮動式風機之Lazy wave動態電纜設計之參考。

The purpose of this study is to focus on investigating the survivability of floating substations with dynamic power cable under normal and extreme environmental conditions, and the floating substation located in the shallow water (50m-100m water depth) of the Hsinchu offshore area, Taiwan. By using OrcaFlex, the tension, curvature and fatigue of the dynamic power cable under the environmental conditions were analyzed and discussed. Meanwhile, 1/42 scale hydraulic experiments for floating substation and dynamic power cable were also conducted. Dynamic power cable under different water depths, different cable buoy configurations, and different directions were observed in this study. After numerical simulation, the result shows that the 100-meter deep dynamic power cable configuration is more appropriate for installation than the 50-meter deep dynamic power cable configuration. As there is more space for the cable to be compressed or stretched, the lazy wave configuration of dynamic power cable can be applied to the water depth of 100 meters in this research. Regarding to the water depth of 50 meters, the dynamic power cable can be placed closer to the seabed or to configure cable in a double wave shape, so that the space for cable movement can be increased horizontally. Furthermore, according to power spectral density (PSD) analysis, the change of PSD for dynamic power cable curvature mainly follows the PSD for wave, and the change of PSD for dynamic power cable tension mainly follows the PSD for pitch response. In the long run, the parameter of fitness including tension force, curvature and fatigue was proposed to investigate the suitable configuration of floating substations with dynamic power cable.

1. ANSYS. (2021). AQWA Theory Manual_R1. ANSYS Inc, Canonsburg, USA. Available at: https://pdfcoffee.com/aqwa-theory-manual-2-pdf-free.html.
2. AON (2014). Avoiding Damage to Offshore Wind assets through a Risk Based Approach.
3. Carbon Trust. (2015). Cable Burial Risk Assessment Methodology Guidance for the Preparation of Cable Burial Depth of Lowering Specification Cable Burial Risk Assessment Methodology: Guidance for the Preparation of Cable Burial Depth of Lowering Specification.
4. Carbon Trust. (2015). Floating Offshore Wind : Market and Technology Review.
5. Carbon Trust. (2018). Floating Wind Joint Industry Project Phase I Summary Report.
6. CIGRE Working Group B1. 40. (2015). TB 610—Offshore Generation Cable Connections.
7. Cummins, W. E., Iiuhl, W., & Uinm, A. (1962). The impulse response function and ship motions.
8. Dieter, G. E., & Bacon, D. (1976). Mechanical metallurgy (Vol. 3). New York: McGraw-hill.
9. DNV GL. (2012). DNV-RP-F401, Electrical power cables in subsea applications.
10. DNV GL. (2016). DNVGL-ST-0145, Offshore substations
11. DNV GL. (2016). DNVGL-ST-0437, Loads and site conditions for wind turbines.
12. DNV GL. (2018). DNVGL-RP-0286, Coupled analysis of floating wind turbines
13. DNV GL. (2018). DNVGL-ST-0119, Floating wind turbine structures.
14. Drexler, E. S., Simon, N., & Reed, R. (1992). Properties of copper and copper alloys at cryogenic temperatures. NIST Mono., Gaithersburg, MD: NIST, 16, 62.
15. Europe, W. (2017). Floating offshore wind vision statement. Wind Europe: Brussels, Belgium.
16. Fenton, J. D. (1985). A fifth-order Stokes theory for steady waves. Journal of waterway, port, coastal, and ocean engineering, 111(2), 216-234.
17. Forestale, P., Accademico, A. (2010). Cable damage can be expensive 32–34.
18. GopiReddy, L. R., Tolbert, L. M., Ozpineci, B., & Pinto, J. O. (2015). Rainflow algorithm-based lifetime estimation of power semiconductors in utility applications. IEEE Transactions on Industry Applications, 51(4), 3368-3375.
19. Hsu, W. Y., Chuang, T. C., Yang, R. Y., Hsu, W. T., & Thiagarajan, K. P. (2019). An Experimental Study of Mooring Line Damping and Snap Load in Shallow Water. Journal of Offshore Mechanics and Arctic Engineering, 141(5).
20. IEC (2004), Power cables with extruded insulation and their accessories for rated voltages above 30kV up to 150kV, IEC60840
21. Ikhennicheu, M., Lynch, M., Doole, S., Borisade, F., MATHA, D., DOMINGUEZ, J., ... & TRUBAT, P. (2021). Review of the state of the art of mooring and anchoring designs, technical challenges and identification of relevant DLCs.
22. Jonkman, J. M., &Buhl, M. L. (2007). Loads Analysis of a Floating Offshore Wind Turbine Using Fully Coupled Simulation Preprint. WindPower 2007 Conference & Exhibition, June, 35.
23. Karlsen, S., Slora, R., Heide, K., Lund, S., Eggertsen, F., & Osborg, P. A. (2009, September). Dynamic deep water power cables. In Proceedings of the 9th International Conference and Exhibition for Oil and Gas Resources Development of the Russian Arctic and CIS Continental Shelf, RAO/CIS Offshore, St Petersburg, Russian (Vol. 15).
24. Maria, I., Mattias, L., Siobhan, D., Friedemann, B., Denis, M., Jose, L., D., Rubén, D., V., Tim, H., Lizet, R., Sabina, P., Climent, M., Pau, T. (2020), Review of the state of the art of mooring and anchoring designs, technical challenges and identification of relevant DLCs.
25. Matsuishi, M., & Endo, T. (1968). Fatigue of metals subjected to varying stress. Japan Society of Mechanical Engineers, Fukuoka, Japan, 68(2), 37-40.
26. Miner, M.A. (1945). Cumulative Damage in Fatigue. Journal of Applied Mechanics, vol. 12, pp. 159-164
27. Morison, J. R., Johnson, J. W., & Schaaf, S. A. (1950). The force exerted by surface waves on piles. Journal of Petroleum Technology, 2(05), 149-154.
28. Orcina. (2021). OrcaFlex Manual, Version 11.1b: Ulverton. Orcina Ltd, Cumbria, UK. Available at: https://www.orcina.com/webhelp/OrcaFlex/Default.htm.
29. Ou, S. H. (1977). Parametric determination of wave statistics and wave spectrum of gravity waves (Doctoral dissertation, Tainan Hydraulics Laboratory of Water Resources Planning Commission-Ministry of Economic Affairs and National Cheng Kung University).
30. Palmgren, A. (1924). Durability of ball bearings. ZVDI, 68(14), 339-341.
31. Rentschler, M. U., Adam, F., & Chainho, P. (2019). Design optimization of dynamic inter-array cable systems for floating offshore wind turbines. Renewable and Sustainable Energy Reviews, 111, 622-635.
32. Rentschler, M. U., Adam, F., Chainho, P., Krügel, K., & Vicente, P. C. (2020). Parametric study of dynamic inter-array cable systems for floating offshore wind turbines. Marine Systems & Ocean Technology, 15(1), 16-25.
33. Rychlik, I. (1987). A new definition of the rainflow cycle counting method. International journal of fatigue, 9(2), 119-121.
34. Shelley, S. A., Boo, S. Y., Kim, D., & Luyties, W. H. (2020, May). Concept Design of Floating Substation for a 200 MW Wind Farm for the Northeast US. In Offshore Technology Conference. OnePetro.
35. Sobhaniasl, M., Petrini, F., Karimirad, M., & Bontempi, F. (2020). Fatigue life assessment for power cables in floating offshore wind turbines. Energies, 13(12), 3096.
36. Taninoki, R., Abe, K., Sukegawa, T., Azuma, D., & Nishikawa, M. (2017). Dynamic cable system for floating offshore wind power generation. SEI Technical review, 84(53-58), 146.
37. Thies, P. R., Johanning, L., & Smith, G. H. (2012). Assessing mechanical loading regimes and fatigue life of marine power cables in marine energy applications. Proceedings of the Institution of Mechanical Engineers, Part O: Journal of Risk and Reliability, 226(1), 18-32.
38. Vryhof Anchors. (2015). Anchor manual.
39. Wichers, J. E. (1979). Slowly oscillating mooring forces in single point mooring systems. In Netherlands Ship Model Basin, Wageningen, Proceedings of the 2nd International Conference on Behaviour of Offshore Structures, BOSS’79, Paper 27, London, England, Volume 1, pp. 357-363, Paper: P1979-4 Proceedings..
40. Zhao, S., Cheng, Y., Chen, P., Nie, Y., & Fan, K. (2021). A comparison of two dynamic power cable configurations for a floating offshore wind turbine in shallow water. AIP Advances, 11(3), 035302.
41. 經濟部水利署第二河川局(2005)。新竹港南海岸環境保護及營造計畫規劃報告。
42. 呂學信、楊敏雄、邱冠融(2012)。懸垂理論在錨碇系統之應用實例分析，第34 屆海洋工程研討會，台南，2012年11月。
43. 呂學德、何無忌、呂威賢、胡哲魁、陳美蘭、連永順（2015）。臺灣離岸風力潛能與優選離岸區塊場址研究，「中華民國第三十六屆電力工程研討會」論文。桃園：中原大學電機工程學系，12月12-13日。
44. 曹淑刚. (2015). 浮筒单点系统缓波式柔性立管性能研究。
45. 財團法人金屬工業研究發展中心(2016)。多台水平軸離岸風力機浮動式承載平台技術開發計畫。研究機構能源科技專案 105 年度執行報告。
46. 徐剑峰(2018)。 浅水斜底地形下超大型浮体单模块系泊系统研究。
47. 福島沖での浮体式洋上風力発電システム実証研究事業総括委員会(2018)。平成30年度福島沖での浮体式洋上風力発電システム実証研究事業総括委員会報告書。
48. 台灣電力股份有限公司(2018)。再生能源發電系統併聯技術要點。
49. 台灣電力股份有限公司(2018)。海上變電站基礎及支撐結構設計及施工研習。
50. 台灣電力股份有限公司(2018)。海上變電站機電配置規劃。
51. 經濟部(2019)。離岸風力發電示範獎勵辦法。
52. 科技部(2020)。抗颱型浮動風機關鍵技術開發與實海域驗證(2/2)。
53. 趙偉廷、楊智傑(2020)。台灣離岸風場於極端氣候條件下之極端波浪特性探討。