• Proceedings of the Korean Society of Computer Information Conference
• /
• 2022.07a
• /
• pp.493-494
• /
• 2022

본 논문에서는 독립형 하이브리드 발전을 위한 효율적안 운영방법을 제안한다. 별도의 정원이 없는 오지에서 독립적으로 동작하기 위해 태양광과 풍력 또는 소수력을 활용하여 두 가지 이상의 발전을 이용하여 발전할 수 있는 하이브리드 발전을 이용한다. 또한 발전된 전원을 야간에도 사용할 수 있도록 저장할 수 있는 배터리를 내장하여 동작할 수 있도록 한다, 배터리의 이용은 발전이 발생되는 구간과 발전이 되지 않는 구간으로 나누어 설계하였다. 발전이 이루어지는 구간은 하나의 발전과 2개의 발전으로 분리하여 하나의 발전만 이루어지는 구간은 일반적인 CC/CV(정전류/전전압) 방식을 이용하여 일반 충전을 수행하고 두 개의 발전이 동시에 이루어지는 구간은 CC(전전류) 모드를 최대한 활용하는 급속 충전을 수행한다. 본 논문에서 제안한 방법은 2개 이상의 발전을 활용하여 독립적인 기능 수행이 가능한 하이브리드 발전을 이용한 독립형 장치로서 장소와 환경의 제한이 적어 실용가능성을 나타내었다.

• Journal of Advanced Marine Engineering and Technology
• /
• v.39 no.1
• /
• pp.68-74
• /
• 2015

This paper describes about the efficiency improvement of switched reluctance generator (SRG) over the rated speed region. Since the current shape has a great influence on the loss of the machine, so the system efficiency can be improved by optimizing the current shape. In case the wide speed range application such as wind power and medium size hydraulic power generation, a method of switching angle control is suggested to obtain the wanted current shapes. In order to verify the method, the experimental platform is set up. The feasibility of the theory is verified by simulation and experimental results.

• Journal of the Korean earth science society
• /
• v.38 no.1
• /
• pp.11-23
• /
• 2017

The short term predictability of wind resources is an important factor in evaluating the economic feasibility of a wind power plant. As a method of improving the predictability, a Bayesian Kalman filter is applied as the model data postprocessing. At this time, a statistical training period is needed to evaluate the correlation between estimated model and observation data for several Kalman training periods. This study was quantitatively analyzes for the prediction characteristics according to different training periods. The prediction of the temperature and wind speed with 3-day short term Bayesian Kalman training at Taebaek area is more reasonable than that in applying the other training periods. In contrast, it may produce a good prediction result in Ieodo when applying the training period for more than six days. The prediction performance of a Bayesian Kalman filter is clearly improved in the case in which the Weather Research Forecast (WRF) model prediction performance is poor. On the other hand, the performance improvement of the WRF prediction is weak at the accurate point.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.33 no.2
• /
• pp.739-748
• /
• 2013

In this study, analytical works for the induced winds due to traveling vehicles on highway have been conducted by Computation Fluid Dynamics (CFD). The traveling condition was considered in two cases: (a) single direction and (b) bi-direction. The analysis was focused on the effects of the induced winds on the upper part of a median strip while the aerodynamic characteristics of the vehicles were directly analyzed in the previous studies. From the analysis results, it has been found that the maximum magnitude of the induced winds was 2.2 m/s when the vehicles travel with the speed of 50 km/h. Additionally, 4.0 m/s and 5.3 m/s were obtained with the speed of 90 km/h and 120 km/h, respectively. Especially, the induced winds was generated about 84% of the vehicle speed at 1.0 m above from the median strip when the vehicles travel with the speed of 120 km/h. The induced winds was maintained during the very short period while the traveling. conclusively, it is noted that the wind power generation can be possible by using the small-sized wind power generators installed on median strips throughout the analytical results in this study.

• New & Renewable Energy
• /
• v.4 no.4
• /
• pp.30-36
• /
• 2008

The possibility of whether the induced wind from a vehicle traveling on highway can be used in wind power generation has been verified through computational flow analysis. The bus which is presumed to accompany relatively strong and wide range of induced wind compared to passenger vehicles because of its wide frontal area has been set as the subject of research. In order to ensure the reliability of research, the flow analysis surrounding the bus on a flat road where median strip is not installed has been compared with a preceding research while the validity of grid system and interpretation method used in this research have been assured by a qualitative method. In case of the median strip type wind power generator system, because it has been verified that a strong streamwise wind speed (5 m/s) is derived from the contraction effect of flow passage between the bus and the median strip while maintaining a relatively consistent upwind wind speed (1.4 m/s) in vertical direction in the wake area after the bus passes by although the change of wind speed is intense, it was decided as having some possibility of wind power generation. In case of the traffic sign panel type wind power generator system installed at the upper top of highway, because the wind speed of 2 m/s level has been derived for a limited time only at a section equal to the length of the bus and a faint induced wind speed less than 0.5 m/s was shown at other regions, it was decided as having almost no possibility of wind power generation.

• Journal of Environmental Impact Assessment
• /
• v.32 no.6
• /
• pp.577-589
• /
• 2023

In Korea, the technical techniques for assessing visual impacts are standardized, but the methods for assessing the marine landscape itself are not standardized and need to be improved. In particular, in the landscape impact assessment of offshore wind power generation in Korea, it is necessary to recognize the landscape itself as a receptor and prepare a system that can evaluate the characteristics and sensitivity of the landscape. In this study, we propose an evaluation method for preparing a marine landscape quality assessment document that reflects the project characteristics of offshore wind power projects, and examine the possibility of utilization by applying it to actual project sites as an example. To evaluate the quality of marine scenery in offshore wind power projects, evaluation items of landscape characteristics, physical characteristics, and socio-cultural characteristics were evaluated based on the preliminary survey contents, and the quality of marine scenery was divided into five grades. Next, the evaluation criteria of the evaluation items were synthesized and the quality of the marine landscape was classified into preservation grade (grade 5), semi-preservation grade (grade 4), buffer grade (grade 3), semi-improvement grade (grade 2), and improvement grade (grade 1). In addition, the Sinan-Ui Offshore Wind Farm, an actual project site, was randomly selected to conduct the evaluation process and examine its utilization. This study aims to complement the existing method of visual impact assessment in offshore wind power projects and evaluate the quality of the marine landscape itself to effectively conserve marine landscape resources during offshore wind power projects. Rather than relying on mechanical and quantitative evaluation, this study is expected to be used as a basis for comprehensive understanding of the location and socio-cultural characteristics of the project site and for communication and cooperation with stakeholders.

• Journal of the Korea Convergence Society
• /
• v.12 no.5
• /
• pp.167-172
• /
• 2021

In the situation where expectations for the growth potential of the domestic offshore wind market are increasing due to the bright growth prospect of the global offshore wind market and the motivated plan of the Korean government, domestic and foreign literature on the direction of offshore wind power generation are examined for the successful development of domestic offshore wind power, the introduction of offshore wind power is diagnosed, and improvement plans are presented for the wind power-related system being promoted by the government. In addition, practical support measures are suggested to foster related SMEs. The results of the study are as follows. First, as technology development is mainly focused on large corporations, the development capacity of small and medium manufacturing industry is very low. Therefore, it is necessary to establish and operate a core center led by government agencies to provide technical support with the initiative of national research institutes and large corporations, and universities and national research institutes should strengthen the independence of small and medium-sized enterprises through training and research and development of professional manpower. Second, as a result of the survey on the practical support plan of the company, it was found that there is a need for various support for technology development and commercialization of produced parts.

• Journal of Environmental Policy
• /
• v.10 no.1
• /
• pp.93-127
• /
• 2011

Investment on technology to obtain green energy is prevailing all over the world. The technology development project is more likely to involve multiple sub-projects, each of which is related to develop elementary technology when the project is larger and nation-wide. However, the methodologies identifying optimal combination of elementary technologies among the candidates have been very few. Hence, the purpose of this paper is to propose a novel methodology which provides an optimal combination of green energy technologies. To do so, to-be developed technologies are clustered with multiple categories. Among the technologies, based on Delphi method, the experts select a representative technology, which is indispensible to the green energy system and has the highest connectivity with other elementary technologies. Then the methodology selects an elementary technology from each technology category based on two metrics: Relatedness with representative technology and project risk. To show the feasibility of the proposed methodology, we applied the methodology to an actual windmill development project.

• 한국신재생에너지학회:학술대회논문집
• /
• 2009.11a
• /
• pp.501-504
• /
• 2009

In order to investigate of possibility for developing urban wind power, wind profile and wind power density are estimated using Sodar and Lidar based on surface. Since poor performance of Sodar and Lidar are often shown in a paticular meteorological condition, inter-comparison and validation with radio-sonde for each of instruments are performed. As a result, Lidar shows a good performance and wind data from Lidar are used to analyze wind profile and wind power density. It can be found that a wind power system mounted tall building in urban area is very attractive.

• Proceedings of the KAIS Fall Conference
• /
• 2011.05a
• /
• pp.69-72
• /
• 2011

정부의 녹생성장 정책에 의해서 신재생에너지들의 보급률이 지속적으로 증가되고 있는 실정이다. 특히 배전계통에 태양광/풍력발전 등 분산전원의 설치가 급증함에 따라 기존 배전계통의 조류흐름이 단방향(One direction)에서 양방향(Bi-direction)으로 변화 되어 배전계통의 운용상에 여러 가지 문제점들이 발생할 가능성이 커지고 있다. 따라서 본 논문에서는 분산전원의 배전계통 연계에 따른 보호기기의 정정 및 보호협조검토가 가능한 보호협조 평가알고리즘을 개발하고, 그 알고리즘을 바탕으로 보호협조 평가시스템을 제작하였다. 이 평가시스템에 분산전원 연계 시, 배전계통의 보호기기들 사이의 보호협조를 검토하여 제안한 알고리즘의 유효성을 확인하였다.