• KEPCO Journal on Electric Power and Energy
• /
• 제2권4호
• /
• pp.631-638
• /
• 2016

해상풍력발전은 경관 및 소음 등의 문제 및 풍황자원 고갈로 인한 사업부지 확보가 어려운 육상풍력발전의 대안으로 주목받고 있다. 해상풍력은 해상에 풍력터빈을 세우기 때문에 경관 훼손이나 소음으로 인한 민원발생이 적고 상대적으로 풍황자원이 풍부하기 때문에 발전생산성이 높다. 그러나 육상풍력에 비해 해상풍력은 설치비가 높아 경제성이 떨어뜨리는 요인으로 작용한다. 이러한 높은 설치비는 해상작업에 필요한 대형장비의 대여기간과 높은 대여료에서 기인하는데, 본 논문에서는 대형 해상장비의 사용을 최소화하여 설치할 수 있는 해상풍력 지지구조의 개념설계를 수행하였다.

• 한국해안·해양공학회논문집
• /
• 제29권1호
• /
• pp.12-19
• /
• 2017

풍력 개발을 위한 해상기상탑은 초기 설치비와 유지보수비가 크기 때문에 윈드 라이다와 같은 원격관측장비를 이용하여 기상탑을 대체할 필요가 있다. 본 연구에서는 해상기상탑에서 윈드 라이다를 동시 운영하고 수집된 풍속 및 풍향의 관측결과를 상호 비교하여 윈드 라이다의 적용성을 검증하였다. 높이별 풍속 및 풍향 관측결과 두 자료간의 크기 및 경향 등의 통계적 특성 차이는 거의 없으며, 기상탑 관측자료는 구조물 차폐영향에 의한 오차가 발생하는 반면, 윈드 라이다는 오차가 없는 보다 정확한 자료를 얻을 수 있는 것을 확인하였다.

• Advances in Computational Design
• /
• 제8권3호
• /
• pp.191-217
• /
• 2023

The objective of this study was to evaluate the foundation structure of a 3.6-MW wind turbine generator (WTG) installed offshore in Western Korea. The ultimate limit state (ULS) and fatigue limit state (FLS) of the multi-pile steel foundation (MSF) installed at the Saemangeum offshore wind farm were structurally investigated using the finite element (FE) software, ANSYS Workbench 19.0. According to the ULS analysis, no plastic deformation was found in any of the components constituting the substructure. At the same time, the maximal stress value reached the calculation limit of 335 MPa. According to the FLS results, the stress concentration factor (SCF) ranged from 1.00 to 1.88 in all components. The results of this study can be applied to determine the optimal design for MSFs.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
• /
• pp.55.2-55.2
• /
• 2011

The final site of offshore wind power plant should be decided by comprehensive examination of various conditions such as wind resource, sea depth, geology, grid connection, social circumstance and environmental issue. Wind condition is typically regarded as the most important factor because wind energy increases in proportion to wind velocity and it directly relates to the amount of power output, efficiency of power plant and profitability. Advanced countries in the offshore wind power sector such as Denmark, UK and Germany, they are analyzing wind resource accurately by installing the meteorological mast in the ocean in order to get the optimal type of wind turbine and maximum generation efficiency. Also, it is made much of designing offshore power plant on the basis of actual measurement by met-mast and those wind farms have a chance to get the loan with reduced interest rate in project financing. In Korea, the HEMOSU-1 is installed in the ocean around Wido island to analyze wind resource of test bed of 100MW offshore wind power on october last year. This paper deals with the design and construction procedure of the first met-mast in Korea and also shows the site characteristics of test bed. Therefore, this paper will give useful information to local governments and private business sector who are trying to construct offshore wind farm and it can also be a good reference for the following projects of meteorological mast in near future.

• 한국환경과학회지
• /
• 제18권8호
• /
• pp.847-855
• /
• 2009

As a part of effort to establish an offshore wind resource assessment system of the Korean Peninsula, a numeric wind simulation using mesoscale climate model MM5 and a spatial distribution of offshore wind extracted from SAR remote-sensing satellite image is compared and analyzed. According to the analyzed results, the numeric wind simulation is found to have wind speed over predication tendency at the coastal sea area. Therefore, it is determined that a high-resolution wind simulation is required for complicated coastal landforms. The two methods are verified as useful ways to identify the spatial distribution of offshore wind by mutual complementation and if the meteor-statistical comparative analysis is performed in the future using adequate number of satellite images, it is expected to derive a general methodology enabling systematic validation and correction of the numeric wind simulation.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2008년도 추계학술대회 논문집
• /
• pp.262-267
• /
• 2008

The long-term wind data are reconstructed from the short-term meteorological data to design the 4 MW offshore wind park which will be constructed at Woljeong-ri, Jeju island, Korea. Using two MCP (Measure-Correlate-Predict) models, the relative deviation of wind speed and direction from two neighboring reference weather stations can be regressed at each azimuth sector. The validation of the present method is checked about linear and matrix MCP models for the sets of measured data, and the characteristic wind turbulence is estimated from the ninety-percent percentile of standard deviation in the probability distribution. Using the Gumbel's model, the extreme wind speed of fifty-year return period is predicted by the reconstructed long-term data. The predicted results of this analysis concerning turbulence intensity and extreme wind speed are used for the calculation of fatigue life and extreme load in the design procedure of wind turbine structures at offshore wind farms.

• 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.

• Wind and Structures
• /
• 제2권1호
• /
• pp.1-23
• /
• 1999

Wind effects are critical considerations in the design of topside structures, overall structural systems, or both, depending on the water depth and type of offshore platform. The reliable design of these facilities for oil fields in regions of hostile environment can only be assured through better understanding of the environmental load effects and enhanced response prediction capabilities. This paper summarizes the analysis and performance of offshore platforms under extreme wind loads, including the quantification of wind load effects with focus on wind field characteristics, steady and unsteady loads, gust loading factors, application of wind tunnel tests, and the provisions of the American Petroleum Institute Recommended Practice 2A - Working Stress Design (API RP 2A-WSD) for the construction of offshore structures under the action of wind. A survey of the performance of platforms and satellite structures is provided, and failure mechanisms concerning different damage scenarios during Hurricane Andrew are examined. Guidelines and provisions for improving analysis and design of structures are addressed.

• Wind and Structures
• /
• 제24권4호
• /
• pp.333-350
• /
• 2017

Differing from the fixed-type, the dynamic motion of floating-type offshore wind turbines is very sensitive to wind and wave excitations. Thus, the sensing and monitoring of its motion is important to evaluate the dynamic responses to the external excitation. In this context, a monitoring system for sensing and processing the wind-induced dynamic motion of spar-type floating offshore wind turbine is developed in this study. It is developed by integrating a 1/00 scale model of 2.5MW spar-type floating offshore wind turbine, water basin equipped with the wind generator, sensing and data acquisition systems, real-time CompactRIO controller and monitoring program. The scale model with the upper rotatable blades is installed within the basin by means of three mooring lines, and its translational and rotational motions are detected by 3-axis inclinometer and accelerometers and gyroscope. The detected motion signals are processed using a real-time controller CompactRIO to calculate the acceleration and tilting angle of nacelle and the attitude of floating platform. The developed monitoring system is demonstrated and validated by measuring and evaluating the time histories and trajectories of nacelle and platform motions for three different wind velocities and for eight different fairlead positions.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2013년도 춘계학술대회
• /
• pp.273-274
• /
• 2013

최근 해상 풍력 발전이 개발됨에 따라 풍력발전타워는 더욱 거대해지고 있으며, 육상의 타워에 비해 파력과 흐름 등 다양한 외력에 노출되어있다. 이에 따라 해상 타워의 기초는 육상 타워 보다 더욱 안정성이 요구된다. 본 연구에서는 현재 관측된 최대 풍속인 60m/s가 해상풍력타워로 향하여 불 때, p-y 관계를 이용해, 원통형, 계단형, 원추형 타워의 기초에 작용하는 풍력과 파력을 해석 하였다.