• 한국태양에너지학회 논문집
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• 제25권4호
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• pp.29-35
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• 2005

Wind turbines can produce an unpolluted electricity getting energy only from the natural resource. It is one of the most economic power generating system among renewables up to now. Currently, ther are many wind turbines in operation world-wide under various external conditions. A wind turbine is composed of many machine components. So it is likely that the many accidents have been occurred in many wind turbines. In this paper, we reviewed "Wind turbine Accident data" of Caithness Windfarms Information Forum 2005. We classified this data and analyzed. The most of wind turbines in our country are foreign product. It is like that application it is possible with information which is important for wind farm operations and maintenance and for the wind turbine design and manufacturing.

• 한국항공우주학회지
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• 제37권11호
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• pp.1121-1130
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• 2009

QuikSCAT 위성의 관측자료를 이용하여 2000년 1월로부터 2008년 12월에 걸쳐 한반도 근해의 풍력자원을 평가 하였다. QuikSCAT 위성은 초단파 scatterometer를 이용하여 해수면 가까이의 풍향과 풍속을 전천후 상태에서 측정한다. 해면으로부터 10 m 높이에서 측정된 풍속을 power law모델을 이용하여 허브 높이에 맞게 외삽 보정하였다. 계산 결과 한반도의 남해와 동해에서 풍력에너지가 상대적으로 우세하다는 것을 알 수 있었다. 풍력 터빈 타워의 설치를 위해 깊은 수심을 피하고 대규모 풍력단지 조성을 위해 남해의 다도해 지역을 피한다면 한반도 서쪽 또는 남서쪽 연안이 대규모 풍력단지 조성에 유리하나 상대적으로 낮은 풍속을 고려한 블레이드 개발을 요한다. 바람 지도를 작성하였으며, 특정 지점에 대한 월별 풍속 변화를 파악하였다. 그리고 풍력에너지 밀도를 이용한 바람장미를 파악하였다.

• 풍력에너지저널
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• 제9권4호
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• pp.32-39
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• 2018

In this study, the annual power production of a wind farm according to obstacles and wind data was predicted for the Garyeok-do wind farm in the Saemangeum area. The Saemangeum Garyeok-do wind farm was built in December 2014 by the Korea Rural Community Corporation. Currently, two 1.5 MW wind turbines manufactured by Hyundai Heavy Industries are installed and operated. Automatic weather station data from 2015 to 2017 was used as wind data to predict the annual power production of the wind farm for three consecutive years. For prediction, a commercial computational fluid dynamics tool known to be suitable for wind energy prediction in complex terrain was used. Predictions were made for three cases with or without considering obstacles and wind direction errors. The study found that by considering both obstacles and wind direction errors, prediction errors could be substantially reduced. The prediction errors were within 2.5 % or less for all three years.

• Wind and Structures
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• 제31권5호
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• pp.419-430
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• 2020

Weibull distribution is a conspicuous distribution known for its accuracy and its usage for wind energy analysis. The two and three parameter Weibull distributions are adopted in this study to fit wind speed data. The daily mean wind speed data of Ennore, Tamil Nadu, India has been used to validate the procedure. The parameters are estimated using maximum likelihood method, least square method and moment method. Four statistical tests namely Root mean square error, R2 test, Kolmogorov-Smirnov test and Anderson-Darling test are employed to inspect the fitness of Weibull probability density functions. The value of shape factor, scale factor, wind speed and wind power are determined at a height of 100m using extrapolation of numerical equations. Also, the value of capacity factor is calculated mathematically. This study provides a way to evaluate feasible locations for wind energy assessment, which can be used at any windy site throughout the world.

• 한국태양에너지학회 논문집
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• 제30권4호
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• pp.79-85
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• 2010

The uncertainty in WindCube LIDAR measurements, which are specific to wind profiling at less than 200m above ground levelin wind resource assessments, was analyzed focusing on the error caused by its volume sampling principle. A two-month SODAR measurement campaign conducted in an urban environment was adopted as the reference wind profile assuming that various atmospheric boundary layer shapes had been captured. The measurement error of LIDAR at a height z was defined as the difference in the wind speeds between the SODAR reference data, which was assumed to be a virtually true value, and the numerically averaged wind speed for a sampling volume height interval of $z{\pm}12.5m$. The pattern of uncertainty in the measurement was found to have a maximum in the lower part of the atmospheric boundary layer and decreased with increasing height. It was also found that the relative standard deviations of the wind speed error ratios were 6.98, 2.70 and 1.12% at the heights of 50, 100 and 150m above ground level, respectively.

• 한국전자통신학회논문지
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• 제13권3호
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• pp.547-554
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• 2018

풍력에너지는 청정 및 재생에너지의 가장 저렴한 모형중의 하나로 널리 알려져 있다. 실제로 몇몇 국가에서는 풍력에너지가 새롭게 건설되는 발전소들 중에서 화석연료 발전단가와 동등한 수준으로 만들어 오고 있다. 해상풍력 에너지 개발은 한국정부의 3020계획 목표달성을 위한 중요한 국내 에너지자원일 것으로 보인다. 풍력프로젝트의 개발단계 중에서 중심이 되는 항목은 풍력자원 평가이다. 풍력자원평가의 기본적인 3가지 등급 또는 단계는 예비부지확정, 부지 풍력자원 평가, 마이크로사이팅 등으로 나누어 분류할 수 있다. 본 연구에서는 6개소 해상기상탑 자료를 기반으로 3단계를 적용하여 전남 해상지역의 풍력발전 용량을 추정하는 것이다. 풍력프로젝트 개발을 위하여 소프트웨어 도구로 25년 이상 실적이 있고 풍력에너지 프로젝트 개발프로그램으로 잘 알려진 WindPRO를 사용하였다. 전남지역 해상풍력발전용량의 설계결과는 6개 풍력단지에서 총 2.52GW로 계산되었다.

• 산업기술연구
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• 제28권B호
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• pp.199-207
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• 2008

A linear wind prediction program, WAsP, was employed to predict wind speed at two different sites located in complex terrain in South Korea. The reference data obtained at locations more than 7 kilometers away from the prediction sites were used for prediction. The predictions from the linear model were compared with the measured data at the two prediction sites. Two compensation methods such as a self-prediction error method and a delta ruggedness index (RIX) method were used to improve the wind speed prediction from WAsP and showed a good possibility. The wind speed prediction errors reached within 3.5 % with the self prediction error method, and within 10% with the delta RIX method. The self prediction error method can be used as a compensation method to reduce the wind speed prediction error in WAsP.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.268-273
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• 2008

A linear wind prediction program, WAsP, was employed to predict wind speed at two different sites located in complex terrain in South Korea. The reference data obtained at locations more than 7 kilometers away from the prediction sites were used for prediction. The predictions from the linear model were compared with the measured data at the two prediction sites. Two compensation methods such as a self-prediction error method and a delta ruggedness index (RIX) method were used to improve the wind speed prediction from WAsP and showed a good possibility. The wind speed prediction errors reached within 3.5 % with the self prediction error method, and within 10% with the delta RIX method. The self prediction error method can be used as a compensation method to reduce the wind speed prediction error in WAsP.

• 신재생에너지
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• 제4권4호
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• pp.23-29
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• 2008

Wind farm development project contains high business risks because that a wind farm, which is to be operating for 20 years, has to be designed and assessed only relying on a year or little more in-situ wind data. Accordingly, long-term correction of short-term measurement data is one of most important process in wind resource assessment for project feasibility investigation. This paper shows comparison of general Measure-Correlate-Prediction models and neural network, and presents new method using neural network for increasing prediction accuracy by accommodating multiple reference data. The proposed method would be interim step to complete long-term correction methodology for Korea, complicated Monsoon country where seasonal and diurnal variation of local meteorology is very wide.

• Wind and Structures
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• 제12권6호
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• pp.505-517
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• 2009

Synchronous wind-induced pressures, measured in wind-tunnel tests on model buildings instrumented with hundreds of pressure taps, are an invaluable resource for designing safe buildings efficiently. They enable a much more detailed, accurate representation of the forces and moments that drive engineering design than conventional tables and graphs do. However, the very large volumes of data that such tests typically generate pose a challenge to their widespread use in practice. This paper explains how a wavelet representation for the time series of pressure measurements acquired at each tap can be used to compress the data drastically while preserving those features that are most influential for design, and also how it enables incremental data transmission, adaptable to the accuracy needs of each particular application. The loss incurred in such compression is tunable and known. Compression rates as high as 90% induce distortions that are statistically indistinguishable from the intrinsic variability of wind-tunnel testing, which we gauge based on an unusually large collection of replicated tests done under the same wind-tunnel conditions.