• 제목/요약/키워드: Offshore wind power system foundation

검색결과 11건 처리시간 0.027초

해상풍력발전 시스템 기초의 설계방법 및 설계인자 (Design method and factors of offshore wind power system foundation)

  • 송원준;경두현;이준환
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2010년도 추계 학술발표회
    • /
    • pp.646-657
    • /
    • 2010
  • Offshore wind power is one of the largest-scale solutions for a nuclear- and pollution-free electricity supply in the future. Recently, the research for offshore wind power has started in Korea. However, there has been little effort specifically made for the exploration and evaluation of mechanical characteristics for offshore underwater soil deposits. In offshore wind power system, this is important as consistent and safe maintenance of structural functionality of the system is key for the wind power system to be successfully implemented. In this study, case examples from foreign offshore wind power sites are selected and analyzed. And design methods and factors of offshore wind power system foundation are investigated.

  • PDF

해상풍력발전기 모노파일 기초공사용 설치시스템 구조 안전성 (Structural Safety in Installation System for Monopile Basic Construction of Offshore Wind Power Generators)

  • 차태형;정원지;이현준
    • 한국기계가공학회지
    • /
    • 제21권2호
    • /
    • pp.31-38
    • /
    • 2022
  • Recently, the development of offshore wind farms based on past technical experiences from onshore wind turbine installations has become a worldwide issue. This study investigated the technical issues related to offshore wind farms and large-diameter monopiles from an economic perspective. In particular, the monopile foundation system (MFS), which is the most important part of the proposed fast construction system, is applied for the first time in Korea, and structural verification is essential because it supports large-diameter monopiles and is in charge of excavation. Therefore, in this study, a rapid construction system for large offshore wind power generators was introduced, and stability verification was performed through the structural analysis of the MFS.

자중조절 기능이 있는 해상풍력 지지구조의 하중 및 구조해석 (Load and Structural Analysis of an Offshore Wind-Turbine Foundation with Weight Control Functionality)

  • 오민우;김동현;김기하;김석태
    • KEPCO Journal on Electric Power and Energy
    • /
    • 제2권3호
    • /
    • pp.453-460
    • /
    • 2016
  • 해상풍력터빈 시스템은 크게 상부의 풍력터빈과 하부의 지지구조로 구성된다. 해상풍력발전은 육상용 풍력발전보다 우수하다는 평가가 지배적이지만 육상용 풍력발전에서 고려되지 않는 파랑에 의한 주기적인 하중이 추가로 고려되기 때문에 다양한 외부 환경조건에 대하여 높은 안정성 확보가 요구된다. 본 연구에서는 전산유체역학 기법을 활용하여 설계된 해상풍력 하부구조에 대한 하중해석을 수행하고 유한요소해석을 통해 설계된 자중조절형 해상풍력 기초에 대한 구조 건전성을 검토하였다.

해상풍력단지 기초에 관한 수치해석적 연구 (Numerical Analysis on Offshore Wind Power System Foundation)

  • 김동호;장원일;김성윤;신성렬;임종세;윤지호
    • Journal of Advanced Marine Engineering and Technology
    • /
    • 제33권2호
    • /
    • pp.355-361
    • /
    • 2009
  • Onshore wind farms having several problems, difficult to secure a building site and incur the enmity of the people. Therefore, offshore wind farms are increasingly expected, because there are huge resource and large site in offshore. If huge wind turbines are constructed, the offshore wind power base is concerned about subsidence. In order to confirm the ground stability, estimation of subsidence is necessary. In this paper, the subsidence is predicted by continuity model when the gravity and the mono-pile base are constructed on soft ground. The FLAC 3D, three dimensional FDM program, was adopted to analysis subsidence. Input factors are yielded by geological information at the yeompo quay in ulsan and the results of laboratory experiments. It has been compared that the original ground with improved ground under the gravity base, and constructed mono-pile under the mono-pile base.

High-Power-Density Power Conversion Systems for HVDC-Connected Offshore Wind Farms

  • Parastar, Amir;Seok, Jul-Ki
    • Journal of Power Electronics
    • /
    • 제13권5호
    • /
    • pp.737-745
    • /
    • 2013
  • Offshore wind farms are rapidly growing owing to their comparatively more stable wind conditions than onshore and land-based wind farms. The power capacity of offshore wind turbines has been increased to 5MW in order to capture a larger amount of wind energy, which results in an increase of each component's size. Furthermore, the weight of the marine turbine components installed in the nacelle directly influences the total mechanical design, as well as the operation and maintenance (O&M) costs. A reduction in the weight of the nacelle allows for cost-effective tower and foundation structures. On the other hand, longer transmission distances from an offshore wind turbine to the load leads to higher energy losses. In this regard, DC transmission is more useful than AC transmission in terms of efficiency because no reactive power is generated/consumed by DC transmission cables. This paper describes some of the challenges and difficulties faced in designing high-power-density power conversion systems (HPDPCSs) for offshore wind turbines. A new approach for high gain/high voltage systems is introduced using transformerless power conversion technologies. Finally, the proposed converter is evaluated in terms of step-up conversion ratio, device number, modulation, and costs.

Foundation Types of Fixed Offshore Wind Turbine

  • Yun Jae Kim;Jin-wook Choe;Jinseok Lim;Sung Woong Choi
    • 한국해양공학회지
    • /
    • 제38권2호
    • /
    • pp.74-85
    • /
    • 2024
  • Offshore wind turbines are supported by various foundations, each with its considerations in design and construction. Gravity, monopile, and suction bucket foundations encounter geotechnical issues, while jacket and tripod foundations face fatigue problems. Considering this, a gravity foundation based on a steel skirt was developed, and a monopile foundation was analyzed for Pile-Soil Interaction using the p-y curve and 3D finite element method (3D FEM). In addition, for suction bucket foundations, the effects of lateral and vertical loads were analyzed using 3D FEM and centrifuge tests. Fatigue analysis for jacket and tripod foundations was conducted using a hotspot stress approach. Some hybrid foundations and shape optimization techniques that change the shape to complement the problems of each foundation described above were assessed. Hybrid foundations could increase lateral resistance compared to existing foundations because of the combined appendages, and optimization techniques could reduce costs by maximizing the efficiency of the structure or by reducing costs and weight. This paper presents the characteristics and research directions of the foundation through various studies on the foundation. In addition, the optimal design method is presented by explaining the problems of the foundation and suggesting ways to supplement them.

해상풍력 석션버켓 기초 구조-지반 상호작용 비선형 구조해석 및 실험결과 비교 (Nonlinear Structure-Soil Interaction Analysis for the Suction Bucket Foundation of Offshore Wind-Turbine)

  • 진정인;김동현;정민욱
    • KEPCO Journal on Electric Power and Energy
    • /
    • 제2권3호
    • /
    • pp.469-475
    • /
    • 2016
  • 최근 석유 에너지 고갈의 문제에 봉착함에 따라 신재생 에너지, 즉 풍력 에너지 분야에 대한 연구가 자연스럽게 부각되고 있다. 그 중 해상풍력은 육상풍력에 비교해 바람 자원이 풍부하기 때문에 효율성 측면에서 주목 받고 있지만 전체 시스템의 설치비용에 따른 경제성이 중요한 문제가 되고 있다. 일반적으로 해상 풍력 사업의 구성비에서 지지구조물 설치비용의 비율이 통상 25% 이상을 차지하는 경향이 있으며, 설계된 지지구조에 대해 정확한 해석과 분석이 가능 하다면 설치 및 시공분야의 경제성을 확보하는데 중요한 역할을 할 수 있다. 본 연구에서는 해상 부유식 풍력발전시스템의 경제성 확보에 중요한 역할을 할 수 있는 석션버켓 기초의 지반연성 비선형 구조해석 기법을 구축하고 이에 대한 검증을 위해 실험결과와 비교검증을 수행하였다.

운전정지 조건에서 5 MW 수평축 풍력터빈 로터의 풍하중 해석 (Wind Loads of 5 MW Horizontal-Axis Wind Turbine Rotor in Parked Condition)

  • 유기완;서윤호
    • 한국풍공학회지
    • /
    • 제22권4호
    • /
    • pp.163-169
    • /
    • 2018
  • 본 연구에서는 운전 정지 상태로 회전하지 않는 수평축 해상 풍력터빈 로터에서 발생하는 풍하중을 풍속, 요 각도, 방위각, 피치 각도를 달리하면서 대기경계층 내에서 작동하는 조건으로 평가하였다. 하중 예측 결과의 검증을 위해 단순화 한 블레이드 형상에 대한 블레이드 요소이론과 단순 계산치를 이용하여 얻어낸 공력 하중을 상호 비교하였으며, 코드와 비틀림 각도가 블레이드 스팬 방향에 따라 변하는 NREL 5 MW급 대형풍력터빈 로터에 대해서는 NREL에서 개발한 FAST 해석 결과와 본 연구의 해석 결과를 비교함으로써 해석 결과의 정확도를 검증하였다. 로터의 하중은 허브 중심을 원점으로 하는 고정된 3축 좌표계에 대해서 힘과 모멘트로 표현되는 6분력 하중으로 나타내었다. 따라서 이 결과는 풍력터빈 시스템의 동적 거동 해석과 로터에서 발생되는 전도 모멘트를 견디기 위해 필요한 지지 구조물의 기초하중 자료로 적용할 수 있다.

프리파일링 자켓 하부구조물용 스태빙시스템의 시공중 구조안전성 평가 (Structural Safety Evaluation of Stabbing System for Pre-Piling Jacket Substructure under Construction)

  • 오영철;류재용;이대용
    • 풍력에너지저널
    • /
    • 제13권3호
    • /
    • pp.79-87
    • /
    • 2022
  • A stabbing system is an underwater jointing structure for positioning the jacket substructure for offshore wind power on top of a pile foundation that is already installed in the seabed. In this paper, the structural safety of the stabbing system currently being developed in South Korea was evaluated through finite element analysis. For this study, conformity of the finite element modeling technique for a gripper (hydraulic cylinder) was reviewed, and the structural safety of the stabbing system was evaluated based on the stress safety factor under three design load combinations (combinations of vertical, shear, and moment loads). From the analysis, it was verified that the pile foundation and the stabbing system mounted on top of it are structurally safe according to the stress safety factor, and there will be no interference between major structural components (i.e., guide cone and pile foundation) due to rotation of the guide cone at the end of the jacket leg.

Analytical framework for natural frequency shift of monopile-based wind turbines under two-way cyclic loads in sand

  • Yang Wang;Mingxing Zhu;Guoliang Dai;Jiang Xu;Jinbiao Wu
    • Geomechanics and Engineering
    • /
    • 제37권2호
    • /
    • pp.167-178
    • /
    • 2024
  • The natural frequency shift under cyclic environmental loads is a key issue in the design of monopile-based offshore wind power turbines because of their dynamic sensitivity. Existing evidence reveals that the natural frequency shift of the turbine system in sand is related to the varying foundation stiffness, which is caused by soil deformation around the monopile under cyclic loads. Therefore, it is an urgent need to investigate the effect of soil deformation on the system frequency. In the present paper, three generalized geometric models that can describe soil deformation under two-way cyclic loads are proposed. On this basis, the cycling-induced changes in soil parameters around the monopile are quantified. A theoretical approach considering three-spring foundation stiffness is employed to calculate the natural frequency during cycling. Further, a parametric study is conducted to describe and evaluate the frequency shift characteristics of the system under different conditions of sand relative density, pile slenderness ratio and pile-soil relative stiffness. The results indicate that the frequency shift trends are mainly affected by the pile-soil relative stiffness. Following the relevant conclusions, a design optimization is proposed to avoid resonance of the monopile-based wind turbines during their service life.