• 한국군사과학기술학회지
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• 제11권2호
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• pp.136-143
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• 2008

A three-wavelength solar bank is a very important part for a solar simulator with commercial superlux lamps. It is projected metal halide lamps to satisfy following points simultaneously: $\pm$10% of uniformity for irradiance of target area and irradiance in each wave region, and $1,232W/m^2$ of maximum solar irradiance in summer. The developed solar lamp bank has been analyzed numerically by commercial programs in this study to carry out experiments. In conclusion, designed B-type heat lamp is not concentrated in one place than designed A-type heat lamp, it is spreaded widely, and it was proved numerical computation. We suggest that solar simulator is applied to actual experiment test through heat flow numerical analysis in solar lamp bank and the lamp is applied private industry or the military using complex environmental assessment test.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.16-17
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• 2008

Recently, characteristic research by the changes in the spectrum, one of the factors that influence analysis of maximum output power of PV module, has been studied. In this paper, a one-day intensity of solar irradiation, change of spectrums with time and electrical output for spectrums are analyzed. As a result, blue-rich wavelength compared with red-rich wavelength has large variation of solar irradiance with time. It is recognized that change of solar irradiance is predominately on variation of blue-rich wavelength. Also in same intensity of solar irradiance, electrical output in blue-rich wavelength was 4-8[%] higher compared to in red-rich wavelength.

• Ocean and Polar Research
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• 제26권3호
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• pp.439-451
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• 2004

Total solar irradiance (750), total UV irradiunce (TUV) and erythemal UV irradiance (EUV) measured at King Sejong station $(62.22^{\circ}S,\;58.78^{\circ}W)$ in west Antarctica have been used together with total ozone, cloud amount and snow cover to examine the effects of ozone, cloud and snow surface on these surface solar inadiunce over the period of 1998-2003. The data of three solar components for each scan were grouped by cloud amount, n in oktas $(0{\leq}n<3,\;3{\leq}n<4,\;4{\leq}n<5,\;5{\leq}n<6,\;6{\leq}n<7\;and\;7{\leq}n<8)$ and plotted against solar zenith angle (SZA) over the range of $45^{\circ}\;to\;75^{\circ}$. The radiation amplification factor (RAE) is used to quantify ozone effect on EUV. RAF of EUV decreases from 1.51 to 0.94 under clear skies but increases from 0.94 to 1.85 under cloudy skies as SZA increases, and decreases from 1.51 to 1.01 as cloud amount increases. The effects of cloud amount and snow surface on EUV are estimated as a function of SZA and cloud amount after normalization of the data to the reference total ozone of 300 DU. In order to analyse the transmission of solar radiation by cloud, regression analyses have been performed for the maximum values of solar irradiance on clear sky conditions $(0{\leq}n<3)$ and the mean values on cloudy conditions, respectively. The maximum regression values for the clear sky cases were taken to represent minimum aerosol conditions fur the site and thus appropriate for use as a normalization (reference) factor for the other regressions. The overall features for the transmission of the three solar components show a relatively high values around SZAs of $55^{\circ}\;and\;60^{\circ}$ under all sky conditions and cloud amounts $4{\leq}n<5$ and $5{\leq}n<6$. The transmission is, in general, the largest in TUV and the smallest in EUV among the three components of the solar irradiance. If the ground is covered with snow on partly cloudy days $(6{\leq}n<7)$, EUV increases by 20 to 26% compared to snow-free surface around SZA $60^{\circ}-65^{\circ}$, due to multiple reflections and scattering between the surface and the clouds. The relative difference between snow surface and snow-free surface slowly increases from 9% to 20% as total ozone increases from 100 DU to 400 DU under partly cloud conditions $(3{\leq}n<6)$ at SZA $60^{\circ}$. The snow effects on TUV and TSO are relatively high with 32% and 34%, respectively, under clear sky conditions, while the effects changes to 36% and 20% for TUV and TSO, respectively, as cloud amount increases.

• Ocean Science Journal
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• 제41권4호
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• pp.235-244
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• 2006

Determining 'photosynthetically active radiation' (PAR) is a key part of calculating phytoplankton productivity in a biogeochemical model. We explore the daily and seasonal variability in the ratio of PAR irradiance to total irradiance that occurred at Ieodo Ocean Research Station (IORS) in the East China Sea under clear-sky conditions in 2004 using a simple radiative transfer model (RTM). Meteorological data observed at IORS and aerosol optical properties derived from Aerosol Robotic Network observations at Gosan are used for the RTM. Preliminary results suggest that the use of simple PAR irradiance-ratio values is appropriate in calculating phytoplankton productivity as follows: an average of $0.44\;({\pm}0.01)$ in January to an average of $0.48\;({\pm}0.01)$ in July, with average daily variabilities over these periods of about $0.016\;({\pm}0.008)$ and $0.025\;({\pm}0.008)$, respectively. The model experiments demonstrate that variations in the major controlling input parameters (i.e. solar zenith angle, precipitable water vapor and aerosol optical thickness) cause PAR irradiance ratio variation at daily and seasonal timescales. Further, increases (>0.012) in the PAR irradiance ratio just below the sea-surface are positively correlated with high solar zenith angles and strong wind stresses relative to those just above the sea-surface.

• 한국태양에너지학회 논문집
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• 제32권6호
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• pp.44-52
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• 2012

In all building's energy simulation applications, solar radiation must be calculated on inclined surfaces. Various solar radiation models based on measured data of specific region were used in building simulation programs. Therefore, we should choose the appropriate solar radiation model for Seoul. The purpose of this study is to compare four solar radiation models on inclined surfaces that are widely used in building energy simulations. In this case, it can be said the appropriate model in Seoul is the Isotropic model.

• 한국태양에너지학회 논문집
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• 제39권4호
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• pp.11-24
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• 2019

The total solar irradiation on horizontal surfaces is separated into the beam and diffuses components. Although horizontal global irradiance is a commonly measured parameter for many sites, horizontal diffuse irradiance is not so readily obtainable. For such sites that measure global irradiation alone, a simple but reasonably accurate method is required to estimate diffuse irradiance from its global counterpart. This study investigates the applicability of correlation coefficients models correlating hourly diffuse and beam fraction and hourly clearness index in Daejeon. The three diffuse to global correlation coefficients models (Orgill and Holland model, CIBSE Guide J model, and Erbs et al. model) are selected and the three modified beam to global correlation coefficients models are generated. MBE, RMSE, r-squared of Daejeon and Daejeon boundary site-fitted models are compared with the case of original coefficients. The comparison result shows that the beam and diffuse to global solar irradiation correlation coefficients models with boundary site-fitted coefficients are best suitable for Daejeon. Further researches will be conducted to find the boundary site-fitting method using measured data of other cities and correlation coefficients models using solar altitude, cloud cover, and sunshine duration.

• 전기전자학회논문지
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• 제22권3호
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• pp.664-671
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• 2018

일반적으로 감지식 태양광 추적 시스템은 태양의 위치를 추적하기 위해 광센서를 사용하여, 최대 전력을 생산한다. 광센서 채택은 시스템 제작 가격을 상승시키고, 오동작에 의한 성능 저하를 초래할 수 있다. 본 논문에서는 IoT플랫폼 기반의 원격무선 모니터링이 가능하고, 광센서가 없는 새로운 태양광 추적 시스템을 제안한다. 태양광 발전을 위해 사용되는 여러 개의 태양광 패널의 출력 전류량을 비교하여 태양 위치를 광센서 없이 추적한다. 추적 성능의 검증을 위해서 12[V] 20[W] 태양광 발전 시스템을 제작하여 실험을 수행하였다. 본 논문에서 제안한 시스템은 IoT 플랫폼을 사용하여 원격모니터링이 가능하기 때문에 기존 태양광 추적 시스템에 비해 설치, 유지 보수 및 기능 확장의 장점이 있다.

• 융복합기술연구소 논문집
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• 제7권2호
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• pp.7-12
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• 2017

At present, the Korea Meteorological Administration (KMA) measures the horizontal solar irradiation and meteorological data with time in 33 areas. Among these measured data, this study analyzed the tendency of applying the new analysis method by using the horizontal solar irradiation and meteorological data with the time which was measured in many regions across the country for thirty years from 1985 to 2014. The method applied to the analysis is to compare the value of the annual total horizontal solar irradiance and meteorological data for one year with the value of those for the previous year of each year, and give +1 when it is higher, and -1 when it is lower. The characteristics and relationships the horizontal solar irradiation and meteorological data in Daegu were evaluated and analyzed. Through the analysis results, the analysis method applied in this study could be well describe the characteristics and relationships of the solar irradiance and meteorological data during some years.

• Asia-Pacific Journal of Atmospheric Sciences
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• 제54권4호
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• pp.599-610
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• 2018

The goal of this study was to statistically analyse the variability of global irradiance and ultraviolet erythemal (UVER) irradiance and their interrelationships with global and UVER irradiance, global clearness indices and ozone. A prediction of short-term UVER solar irradiance values was also obtained. Extreme values of UVER irradiance were included in the data set, as well as a time series of ultraviolet irradiance variability (UIV). The study period was from 2005 to 2014 and approximately 250,000 readings were taken at 5-min intervals. The effect of the clearness indices on global irradiance variability (GIV) and UIV was also recorded and bi-dimensional distributions were used to gather information on the two measured variables. With regard to daily GIV and UIV, it is also shown that for global clearness index ($k_t$) values lower than 0.6 both global and UVER irradiance had greater variability and that UIVon cloud-free days ($k_t$ higher than 0.65) exceeds GIV. To study the dependence between UIVand GIV the ${\chi}^2$ statistical method was used. It can be concluded that there is a 95% probability of a clear dependency between the variabilities. A connection between high $k_t$ (corresponding to cloudless days) and low variabilities was found in the analysis of bidimensional distributions. Extreme values of UVER irradiance were also analyzed and it was possible to calculate the probable future values of UVER irradiance by extrapolating the values of the adjustment curve obtained from the Gumbel distribution.

• 한국태양에너지학회 논문집
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• 제22권3호
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• pp.21-30
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• 2002

Images taken by geostationary satellite may be used to estimate solar irradiance fluxes at earth's surface. It is based on the empirical correlation between a satellite derived cloud index and the irradiance at the ground. For the validation. estimated solar radiation fluxes are compared with observed solar radiation fluxes at 16 sites over the Korean peninsular from January 1982 to December 2000. Estimated solar radiation fluxes show reliable results for estimating the global radiation with average deviation of -5.6 to +2.8% from the measured values and the yearly averaged horizontal global insolation of Korean peninsula was turned out to be $3.038kcal/m^2.day$.