• Journal of the Korean Solar Energy Society
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• v.30 no.2
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• pp.1-9
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• 2010

This study has intended to analyze citizen's recognition on Photovoltaic (PV) System Supply Policy in Korea. To reach this goal, this study has employed a survey method and statistical analysis. We have asked 140 citizens knowing the policy to some degree to answer questionnaires including various contents related to PV supply policy driven by central government of Korea. The contents of questionnaires consist of three parts: 1) supply policies, 2) PV system and 3) expected effect from the policy. To verify any differences among the characteristics of respondents, ANOVA (Analysis of Variance) was carried out in 95% confidence level. This study has found the following results: 1) most citizens were positive about the 'Photovoltaic System Supply Policies'; 2) most citizens anticipated the policy would be helpful to cope with the environmental problems and energy crisis and 3) there exit subtle differences between residents according to the respondent's characteristics such as sex, age, occupation, and housing type.

• Current Photovoltaic Research
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• v.9 no.3
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• pp.106-109
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• 2021

In order to perform photovoltaic (PV) operation and management (O&M) efficiently, individual PV module monitoring is becoming more important. In this research, we developed wireless IoT sensor which can monitor individual photovoltaic modules. This IoT sensor can detect the output voltage, current and module temperature of individual modules and provide monitored data by wireless communication. Measured voltage error was 1.23%, and it shows 16.6 dBM, 0.42sec and 7.1 mA for voltage, transmittance output, response time and mean power consumption, respectively. IoT sensors were demonstrated in the test field with real climate environment condition and each of 5 sensors showed precise results of voltage, current and temperature. Also, sensors were compared with commercial power-optimizers and showed result difference within 5%.

• Journal of the Korean Society of Safety
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• v.34 no.1
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• pp.21-26
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• 2019

This paper is purposed to develop hardware for controlling abnormal temperature that can occur environment and component itself in PCS. In order to be purpose, the hardware which is four part(sensing, PLC, monitoring and output) keep detecting temperature for critical components of PCS and can control the abnormal temperature. Apply to the hardware, it is selected to PV power generation facilities of 20 kW in Cheong-ju city and measured the data for one year in 2017. Through the temperature data, it is found critical components of four(discharge resistance, DC capacitor, IGBT, DSP board) and entered the setting value for operating the fan. The setting values for operating the fan are up to $130^{\circ}C$ in discharge resistance, $60^{\circ}C$ in DC capacitor, $55^{\circ}C$ in IGBT and DSP board. The hardware is installed at the same PCS(20 kW in Cheong-ju city) in 2018 and the power generation output is analyzed for the five days with the highest atmospheric temperature(Clear day) in July and August in 2017 and 2018 years. Therefore, the power generation output of the PV system with hardware increased up to 4 kWh.

• Current Photovoltaic Research
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• v.7 no.2
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• pp.51-54
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• 2019

The high density module (HDM) has advantages for its larger active area and smaller current density. This new way of making a photovoltaic (PV) module method has benefit for increasing module power with the same installed area. Because HDM consisted with serially connected PV strings, loss of strings during the fabrication process can increase the overall production cost.1-2 This study investigates the rework conditions of the shingled strings with electrically conductive adhesives (ECA). By heating the electrically connected area of a fabricated string, cured area become soft and a string can be detached for the rework process. After rework process, a refabricated string showed 5~10% increased output power compared to before rework process and reached to the 90~95% output power compare to the undamaged strings.

• New & Renewable Energy
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• v.17 no.3
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• pp.16-23
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• 2021

Recently, the Korean government announced a plan to activate renewable energies, with focus on clean energy sources such as solar and wind power as the core and the goal of achieving carbon neutrality by 2050. Unlike other photovoltaic (PV) systems, offshore PV installations are advantageous for large-scale expansion because of the ease of securing sites; they also enable lowering the power generation costs based on construction of large-scale power facilities of megawatt class or higher owing to low noise and landscape damage. However, any power generation should proceed with consideration of the special environmental conditions of the ocean. Above all, when installing large-scale facilities, it is important to reduce fluctuations of the structure and secure stability to actively respond to waves. This study is concerned with the development of a floating body technology that actively responds to waves so as to enable commercialization of offshore solar power. A unit platform for research and development on offshore PV generation was installed in the Saemangeum sea, and the structural fluctuations and stability were analyzed to ensure conformity with the major performance indicators.

• Journal of Digital Convergence
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• v.15 no.9
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• pp.231-239
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• 2017

Solar energy is attracting attention as an alternative to fossil fuels. However, there was a lack of discussion on the overall research direction and future direction of research in technology development. In order to develop more effective technology, we analyzed and discussed the technology trend of solar energy using patent data and thesis data. As an analysis method, topics were selected by using topic modeling and text mining, the increase of included keywords was analyzed, and the direction of development of solar technology was analyzed. Research on solar power generation technology is expected to proceed steadily, and it is analyzed that intensive research will be done especially on high efficiency and high performance technology. Future studies could be conducted by adding overseas patent data and various paper data.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.28-36
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• 2018

Islands are supplied with power from diesel generation or from photovoltaic power generation, and problems with offshore environmental impacts (age deterioration, salt pollution), environmental pollution (exhaust gas, noise, dust) and power generation costs (installation, maintenance) have increasingly emerged. In 2016, the cost recovery rate was only 27%, and deficits reached 73% on 65 islands managed by KEPCO. In terms of deficits, the costs incurred in the power generation sector accounted for 91%, with the ratio of fixed costs at about 60%. Analysis suggests that operating costs can be reduced with an optimal power supply system that improves power generation efficiency and makes operating systems more efficient. Therefore, it is possible to simplify fuel transportation and facility maintenance, because one island integrates the power plants of remote islands, and offshore cable is used to supply power to the other islands. From the economic evaluations in this paper, an algorithm deciding offshore cable layout validity for an integrated power supply between adjacent islands is presented. Simulation results based on the proposed algorithm confirmed that an integrated power supply is economical for existing stand-alone operations on islands having diesel generation, low peak power, and near distances.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1354-1355
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• 2011

화석에너지의 유한성과 공해문제로 인해 대체에너지 개발에 대한 관심이 고조되는 가운데 태양광발전과 풍력발전이 그 중에서 가장 활발하게 연구되고 실제 이용비율도 상당히 높은 편이다. 이는 외기 기후변화에 대한 상대적인 보완성을 가진 두 가지 형태의 에너지원으로부터의 에너지변환과정으로 인해 그 이용이 더욱 부각되고 있다. 기존의 풍력발전시스템, 태양광발전시스템 또는 풍력/태양광 복합발전시스템 중 대형발전시스템의 경우는 일사량센서나 풍속센서를 부착하여 최대 출력점 제어나 외기환경 인식을 위해서 일사량이나 풍속과 같은 외기환경정보를 획득하여 사용하며 이를 교육용 또는 외기환경정보를 분석하는데 이용하기도 하고, 다양한 표시장치를 통해 표시하기도 한다. 그러나, 일사량센서나 풍속센서는 고가의 센서로 대형 태양광발전시스템이나 풍력발전시스템에서는 여러 개소의 설치를 통해 보다 정확한 정보를 획득해야 하며, 이를 위해 많은 개수의 센서가 필요하다. 현실적으로 여러 개의 센서는 고가의 설치 비용으로 인해 샘플링을 위해서만 설치될 뿐 발전시스템의 설치사이트의 다양한 분석이 어려운 점이 있었다. 본 논문에서는 풍속센서나 일사량센서 없이 태양전지모듈로부터 직접 일사량을 검출하는 방식의 일사량 정보획득과 풍력발전시스템에서의 풍속정보를 획득하는 방법을 제안한다.

• Korean Journal of Construction Engineering and Management
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• v.18 no.5
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• pp.11-19
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• 2017

The purpose of this study is to analyze the efficiency of PV according to installation condition in the complex type buildings. For this purpose, annual performance of solar power generation in a certain area was investigated and various methods were conducted including post operation evaluation. In addition, we tried to find out influencing factors that affect the efficiency and sought to identify their relative impact of degree through the data analysis and site visits together. In the middle of this process we can draw up major considerations for the efficient photovoltaic power generation installation. In the mean while, previous studies are making something new related with method for efficiency enhancement and individual influential factors based on experimental environment rather than the empirical data site based. As a result of the study, it was confirmed that even if installed in the same area, the power generation efficiency is 1.5 times as high as the installation condition. Furthermore, statistical analyses were performed on azimuth, tilted angle and shade, which are variables affecting conversion efficiency, and it was statistically confirmed that all variables are meaningful factors that affect the conversion efficiency which is a dependent variable. The most influential factor is the azimuth, followed by the tilted angle and the shade factor. From this result, we expect to be able to provide installation guidelines for the solar power generation equipments on the rooftop zone.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.640-644
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• 2009

현재 태양광 산업에서는 고정식 태양광 발전장치보다 발전 효율이 우수한 추적식 태양광 발전장치를 개발하는 연구가 활발하게 진행되고 있다. 추적식 태양광 발전장치는 고정식에 대비하여 단위면적당 일사량을 최대로 유지할 수 있을 뿐만 아니라, 일조시간을 최대로 하여 태양전지의 발전효율을 극대화할 수 있다. 따라서 정밀하면서도 저렴한 태양위치 추적장치는 태양광 발전사업의 경제성을 높이고, 성능 대비 투자비용을 낮춰 태양광 발전설비의 보급을 촉진시켜줄 수 있는 중요한 기술이다. 본 연구는 태양위치를 감지하는데 센서를 사용하지 않고 천문학과 수학을 이용하여 정밀도 1분($0.016^{\circ}$)이내의 태양위치를 계산하는 알고리즘에 관한 것이다. 본 연구에서 제안하는 알고리즘은 장치의 제작비용을 낮추어 줄 뿐 아니라, 발전효율도 높여준다. 구현된 알고리즘을 적용시킨 추적식 태양광 발전장치를 운용 실측한 결과, 최대 30초($0.0038^{\circ}$)의 오차를 보여 추적식 발전장치의 경제성을 높일 수 있고, 시간복잡도(Time Complexity)와 공간복잡도(Spatial Complexity)가 낮아 실시간 태양 추적장치에 최적임을 확인하였다.