臺灣博碩士論文加值系統

因應全球對再生能源的重視與發展，太陽能發電與風能發電在各國政府的推廣下已為未來的趨勢。經濟部能源局計畫設置千架海上風力發電機組的能源政策。離岸風機勢必需要海底電纜作為電力的傳輸媒介，連結離岸風場與陸上變電站。海底環境複雜，海纜鋪設不當以及人為破壞皆有可能對海纜的安全運行造成相當的威脅。而海纜在受到機械傷害時通常會產生軸向拉伸，軸向拉伸是造成海纜損壞的主要原因之一。海纜結構複雜，由螺旋結構的鎧裝以及其他功能構件如護套、絕緣和導體所組成。而螺旋鎧裝在受到拉伸荷載作用時除了軸向伸長外還會對電纜產生扭力。在運送和安裝過程時也會對電纜造成扭轉。因此除了分析拉力以外，扭力的分析也是相當重要的。為防止海纜破壞的發生，有必要對海纜的拉伸與扭轉力學過程進行分析。
本研究分為兩種，其一為研究海底電纜在拉伸與扭轉作用下的力學行為分析。配合靜力分析軟體ANSYS-STATIC STRUCTURAL進行結構分析，並對電纜的拉伸與扭轉性能進行剛度驗證。其二為對海底電纜的鎧裝與內核進行設計分析。由理論分析可知，影響電纜剛度的參數為鎧裝的角度與直徑。本研究將探討當鎧裝角度與直徑改變時，其截面性能的變化，並改變鎧裝層數和導體數目以探討模型的優劣。同時加入水壓的影響，研究水壓對電纜拉力與扭力的變化情形。

In response to the global emphasis and development of renewable energy, solar power, and wind power generation have become the future trend under the promotion of governments. The Energy Bureau of the Ministry of Economic Affairs plans to promulgate an energy policy to set up thousands of offshore wind turbines. Offshore wind turbines are bound to require submarine cables as a transmission medium for electricity, connecting offshore wind farms and onshore substations. The submarine environment is complex, and improper laying of submarine cables and man-made damage may pose a considerable threat to the safe operation of submarine cables. While the submarine cable is mechanically damaged, it usually produces axial force, which is one of the main causes of damage to the submarine cable. The structure of the submarine cable is complex, consisting of the spiral armor and other functional components such as sheath, insulation, and conductor. The spiral armor also generates a torsion moment in addition to the axial elongation when subjected to a tensile load. However, the cable is also twisted during shipping and installation. Therefore, in addition to analyzing the tensile force, the analysis of the torque is also very important. In order to prevent the occurrence of damage, it is necessary to analyze the tensile and torsional mechanical processes of the submarine cable.
This study is divided into two types, one of which is to investigate the mechanical behavior of submarine cables under tension and torsion. The structural analysis was carried out with the static analysis software ANSYS-STATIC STRUCTURAL, and the stiffness of the cable would be verified by the tensile and torsional properties. The second is the design analysis of the armor and the core of cable. According to theoretical analysis, the main parameters affecting cable stiffness are the spiral angle and diameter of the armor. This study will investigate the change in cross-sectional properties when the angle and diameter of the armor are varied. Moreover, the number of armor layers and the number of conductors will also be changed to explore the advantages and disadvantages. Meanwhile, the effect of water pressure on the tensile force and torsional moment of the cable will be studied.

論文審定書 i
摘要 ii
ABSTRACT iii
TABLE OF CONTENTS v
LIST OF FIGURES viii
LIST OF TABLES xi
CHAPTER 1 INTRODUCTION 1
1.1 Background Information 1
1.2 Research Motivation 3
1.3 Literature Review 5
1.3.1 Theoretical Analysis Methods 5
1.3.2 Numerical Analysis Method 7
1.3.3 Summary of section 9
1.4 Research Objectives 9
CHAPTER 2 SUBMARINE CABLE OVERVIEW 11
2.1 Cable Design 11
2.1.1 Conductor 12
2.1.2 Insulation System 12
2.1.3 Armor 14
2.1.4 Sheath 15
2.2 Cable Usage 15
2.3 Cable Installation 16
2.3.1 Installation Methods 17
2.3.2 Loads during Installation 19
2.4 Summary of Chapter 19
CHAPTER 3 THEORETICAL ANALYSIS AND METHODOLOGY 20
3.1 Geometric Model 20
3.2 Theoretical Analysis Method 22
3.2.1 Hruska Theoretical Model 23
3.2.2 Knapp Theoretical Model 23
3.2.3 Tensile Load 25
3.2.4 Torsional Load 28
3.3 Methodology 29
3.3.1 Solid Works CAD 29
3.3.2 Static Structural on ANSYS 29
3.3.3 The Assumption of Static Structural 30
3.3.4 The Foundation of Static Structural 31
3.3.5 Contact setting in ANSYS 31
3.4 Summary of Chapter 37
CHAPTER 4 FINITE ELEMENT ANALYSIS 38
4.1 Submarine Cable Model Description 38
4.2 Finite Element Model in ANSYS 40
4.2.1 Modeling in ANSYS 40
4.2.2 Modeling Assumption 44
4.2.3 Model Verification 44
4.3 Translations in Each Layer of Submarine Cable 47
4.3.1 Set Path in Finite Element Analysis 47
4.3.2 Tensile Force 48
4.3.3 Torsional Moment 50
4.4 Stress Analysis of Submarine Cable 52
4.4.1 Distortion Energy Theory 52
4.4.2 The Equivalent Stress of Cable Cross-Section 53
4.4.3 Armor Stress Distribution 55
4.5 The Coupling Relationship under Combined Tension and Torsion 59
4.6 The Effect of Compressive Pressure on Tension and Torsion 62
4.7 Summary of Chapter 66
CHAPTER 5 OPTIMAL CROSS-SECTIONAL DESIGN 67
5.1 The Effect of Spiral Angle and Wire Diameter on Stiffness 67
5.1.1 Model Description 68
5.1.2 Stiffness Analysis 69
5.2 Comparison of Single and Double-Layer Armor 72
5.2.1 Model Description 72
5.2.2 Cross-Sectional Properties 73
5.3 The Design of Cross-Sectional Core Number 76
5.3.1 Stiffness Analysis 78
5.3.2 Radial Deformation 81
5.3.3 Contact Stress 86
5.3.4 Effects of Compressive Pressure 88
5.3.5 Couple Effects of Tensile, Torsional and Compressive Load 90
5.4 Summary of Chapter 98
CHAPTER 6 CONCLUDING REMARKS 99
6.1. Conclusions 99
6.2. Recommendations for Future Research 102
REFERENCES 103
APPENDIX 105

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