• 대한조선학회논문집
• /
• 제54권3호
• /
• pp.196-203
• /
• 2017

In general, the installation of offshore wind turbine have been carried out by a jack-up barge or wind turbine installation vessel. In case of using jack-up barge, an additional barge is required to transport offshore wind turbines. During the transportation, barge is affected by environmental conditions such as wave, wind etc. So, it is important to secure the static and dynamic stability of the barge. In this study, fundamental research was performed to evaluate the stability of barge due to use the guide frame. The analysis for static stability of barge was performed under the two loading conditions with or without wave and those results were evaluated according to the Ministry of Oceans and Fisheries rules. Also motion analysis was performed under the ITTC wave spectrum using buoy data and evaluated based on NORDFORSK guideline by using commercial software Maxsurf Motions.

• International Journal of Naval Architecture and Ocean Engineering
• /
• 제9권1호
• /
• pp.45-54
• /
• 2017

The purpose of this study is to evaluate various means of wind power turbines installation in the Korean west-south wind farm (Test bed 100 MW, Demonstrate site 400 MW). We presented the marine environment of the southwest offshore wind farm in order to decide the appropriate installation vessel to be used in this site. The various vessels would be WTIV (Wind turbine installation vessel), jack-up barge, or floating crane ${\cdots}$ etc. We analyzed the installation cost of offshore wind turbine and the transportation duration for each vessel. The analysis results showed the most suitable installation means for offshore wind turbine in the Korean west-south wind farm.

• 대한임베디드공학회논문지
• /
• 제14권6호
• /
• pp.347-353
• /
• 2019

Electric-hydraulic sever cylinders are used in many offshore applications such as wind energy farms, solar farms and plants. Jack-up barges are often used for these offshore system operations. Jack-up barge control is up/down by hydraulic cylinder position control. Working in harsh environments can lead to changes in internal parameters. This nonlinearity makes precise control difficult. In order to overcome the problems, we proposed a method of unknown-parameter estimation algorithm based on measurements obtained by system. In this paper, we employee Unscented Kalman filter (UKF) to estimate states and unknown-parameter from augmented nonlinear equation. Performance of estimation results is verified in simulation on an environments of Matlab. The estimation results of the state and unknown-parameter show that the estimation error of unknown-parameter is reduced according to decreasing the state estimation error.

• 한국지반환경공학회 논문집
• /
• 제17권10호
• /
• pp.13-22
• /
• 2016

본 연구에서는 가이드라인에 제시된 스퍼드캔의 설계 프로세스에 따라 서남해 연약지반 조건에 최적화된 스퍼드캔의 형상 및 크기를 도출하고, 안정성 평가를 위한 복합하중 작용 시의 항복면을 정의하였다. 이를 위해 일정한 수직하중 작용 시 수평하중과 모멘트 하중을 가하여 수평하중-수평변위, 모멘트-회전변위간의 상관관계를 통해 항복면을 산출하는 프로브 방법을 적용하였다. 분석 결과, 복합하중을 고려한 서남해 지반에서 요구되는 스퍼드캔의 직경은 8m로 나타났으며, 가이드라인에 제시된 지지력 산출경험식을 통해 지지력을 계산할 경우 얕은 심도에서는 비교적 정확한 지지력의 예측이 가능한 것으로 나타났다. 제시된 항복면은 Mohr Coulomb 모델과 Hardening soil 모델을 각각 적용하였을 시 서로 다른 형상을 보였으나, 스퍼드캔의 직경이 증가함에 따라 점차 확장되는 경향을 보였다. 본 연구를 통해 제시된 항복면은 실제 스퍼드캔이 설치될 지역의 지반조사 결과, 가이드라인과 더불어 추후 해상풍력단지 조성 시 스퍼드캔의 안정성 평가에 유용한 참고자료로 활용될 수 있을 것으로 판단된다.