• 제목/요약/키워드: Irradiance Distribution

검색결과 77건 처리시간 0.027초

Measurement of Solar Cell Using LED-based Differential Spectral Responsivity Comparator under High Background Irradiance

  • Zaid, Ghufron;Park, Seong-Chong;Lee, Dong-Hoon;Park, Seung-Nam
    • 한국광학회:학술대회논문집
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    • 한국광학회 2009년도 동계학술발표회 논문집
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    • pp.293-294
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    • 2009
  • The spectral responsivity of solar cells has been measured under high background irradiance using an LED-based differential spectral responsivity Comparator (DSR-C). The comparator developed is fully automated and has some advantages: It does not need a chopper to modulate the light. Unlike the conventional method, it does not require a monochromator to select wavelength. It covers a wavelength range up to 1200 nm. The wavelength range of the comparator is limited by the spectral power distribution of the LEDs and the spectral responsivity of the standard detector. An active temperature control was utilized to meet the specified standard conditions of solar cell test. This work shows the effect of different levels of background irradiance on the spectral responsivity and the importance of same background irradiance for solar cell test as specified by the corresponding standard.

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최적의 램프뱅크형태를 결정하기 위한 열유동 해석 (A Thermal Flow Analysis for an Optimal shape of Solar Lamp Bank)

  • 백상화
    • 한국태양에너지학회 논문집
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    • 제32권4호
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    • pp.82-89
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    • 2012
  • This study is on the thermal flow analysis to select an optimal shape of solar lamp bank. Solar Lamp bank is designed by the lamp bank design program based on point light source theory. The reliability of the program for lamp bank design is verified through irradiance variation experiments of a kind of lamp according to horizontal distance. Solar lamp bank facilitates heat distribution and satisfies the irradiance in the three wave length which test guidelines require. Among the 4 kinds of lamp bank, since lamp bank type D satisfies uniformity ${\pm}10%$ and also doesn't exceed total irradiance 1,232 $W/m^2$, type D is finally selected.

랜덤매질을 통과한 광도의 확률분포에 관한 수치해석적 연구 (Numerical Study on the Probability Distribution of Irradinace through Random Media)

  • 백정기;손창수
    • 한국통신학회논문지
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    • 제18권4호
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    • pp.457-467
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    • 1993
  • 랜덤매질을 통과한 광파에 대한 중요한 통계적인 양 중의 하나는 광도의 확률분포이다. 현상학적 모델로부터 여러가지 분포함수들이 제안되었다. 본 논문에서는 컴퓨터 시뮬레이션에 의해 광도데이타를 얻고, 모멘트법, 히스토그램법 및 $x^2$-테스트에 의해 제안된 분포함수들을 시뮬레이션 데이터와 비교함으로써 각 분포함수들의 타당성을 조사하고자 한다.

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실내배양에서 해산 녹조 납작파래 (Enteromorpha compressa)의 생장에 미치는 광도와 염분 및 온도와 염분의 복합효과 (Combined Effects of Irradiance-Salinity and Temperature-Salinity on the Growth of Enteromorpha compressa (Chlorophyta) in Laboratory Culture)

  • 김광용
    • Journal of Plant Biology
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    • 제36권3호
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    • pp.219-224
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    • 1993
  • The effects of environmental factors on the growth of Enteromorpha compressa germlings from Daeyulri (34$^{\circ}$36'N; 127$^{\circ}$47'E), the southern cost of Korea were examined in laboratory culture through combinations of irradiance and salinity and temperature and salinity. They showed a maximum growth rate at 125 $\mu$E.m-2.s-1 and 32$\textperthousand$ of irradiance and salinity combination, and at 15$^{\circ}C$ and 32% of temperature and salinity combination. Optimal parameters for the growth of germlings were 15$^{\circ}C$, 125 $\mu$E.m-2s-1 and 32$\textperthousand$. The germlings of E. compressa were survived in a wide range of irradiance, temperature and salinity levels, even though they had relatively low irradiance optimum. In the field E. compressa occurred commonly during autumn and spring seasons and disappeared in summer, except for particular habitats. This may be caused by the salinity and water temperature of this area rarely drop below 26$\textperthousand$ and 8$^{\circ}C$ during winter. A broad tolerance to environmental and rapid growth of germlings made them a wide geographical distribution over the world and a survival in both the upper and lower intertidal zones.

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복수 조합에 의한 고휘도 발광 다이오드의 분광분포와 수중투과특성 (Spectral Irradiance and Underwater Transmission Characteristics of a Combined High-Luminance Light-Emitting Diodes as the Light Source for Fishing Lamps)

  • 최석진
    • 한국수산과학회지
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    • 제42권6호
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    • pp.703-710
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    • 2009
  • The spectral irradiance and underwater transmission characteristics of a combined high-luminance light-emitting diode (LED) lights have been studied to evaluate suitable light sources for fishing lamps of the next generation. The wavelengths at which the irradiance was maximum were changed from 473, 501, 525, and 465 nm for blue, peacock blue, green, and white LED light to 475, 504 and 528 nm for [$F_{WB}$], [$F_{PB}$] and [$F_{GB}$] combined LED lights, respectively. If the irradiance characteristics at 400-700 nm wavelengths are set as 100%, the irradiance rates at 450-499 nm and 500-549 nm were decreased from 82.4% and 56% for blue, peacock blue LED light to 60.0%, 38.5% for [$F_{WB}$], [$F_{WP}$] combined LED lights. The underwater transmission characteristics of the combined LED lights were superior in the order [$F_{WB}$], [$F_{BP}$], [$F_{GB}$] in optical water type I; [$F_{WB}$], [$F_{PB}$], [$F_{GP}$] in optical water type II-III; and [$F_{GP}$], [$F_{WP}$], [$F_{PB}$] in optical water type 1. Setting the 10m depth underwater transmission characteristics of the combined LED lights in optical water type I at 100%, the transmission of water types II, III and 1 drops to 29.5%, 8.0% and 2.2%. Based on the distribution of spectral irradiance and underwater transmission characteristics calculated in optical water types II-III, where was the jigging ground for fishing lamps, the [$F_{WB}]$ and [$F_{GP}$] combined LED lights can be used as a suitable light sources for fishing lamps of the next generation.

일사량 확률분포함수를 이용한 태양광 발전시스템 발전량 예측 (Photovoltaic Generation System Output Forecasting using Irradiance Probability Distribution Function)

  • 이일룡;배인수;정창호;김진오;심헌
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 A
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    • pp.548-550
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    • 2004
  • This paper suggests a methodology for calculation of photovoltaic(PV) generation system output using probability distribution function, PV way efficiency and PV system design Parameters. Long term irradiance recorded for every hour of the day for 11 years were used. For goodness-fit test, several distribution functions are tested by Kolmogorov- Smirnov(K-S) test. And the calculated generation output is compared with that of CMS(Centered Monitoring System), which can monitoring PV generation output of each PV generation site.

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솔라시뮬레이터의 램프뱅크 설계에 관한 연구 (A STUDY ON LAMP BANK DESIGN OF SOLAR SIMULATOR)

  • 백상화
    • 한국전산유체공학회지
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    • 제17권3호
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    • pp.45-52
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    • 2012
  • This paper is a study on the design of the solar lamp bank which is a very important part of the solar simulator with the commercial metal halide lamps and infrared lamps. Lamp Bank is designed by the lamp bank design program based on point light source theory. The reliability of the program for lamp bank design is verified through irradiance variation experiments of a kind of lamp according to horizontal distance. Solar lamp bank facilitates heat distribution and satisfies the irradiance in the three wave length which test guidelines require. The shape of the ceiling board next to the lamp bank to promote the lamp cooling efficiency and to reduce temperature deviation and air velocity deviation in the chamber is so creative. The ceiling board of partial closed type is the best among several types.

맥류의 기공확산저항의 일중변화와 입위별 기공의 분포 (Diurnal Changes in Stomatal Diffusion Resistance and Distribution of Stomata on Different Leaf Positions in Barley and Wheat)

  • 이호진;윤진일;이광회
    • 한국작물학회지
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    • 제26권1호
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    • pp.45-50
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    • 1981
  • Diurnal changes in leaf stomatal resistances were measured on leaf positions and both surfaces to investigate the stomatal response to irradiance in wheat, var. Chokwang and barley, var. Dongbori 1. Stomatal frequency and size were also determined to explain the control mechanism of gas exchanges in two species. The leaf diffusive resistances of two species decreased, as the sun rose, to minimum at 10 to 11 o'clock a.m. and increased gradually in the afternoon, even faster at sunset. As the adaxial irradiance increased, stomatal resistances decreased sensitively in the range of 30uEm$^{-2}$ㆍsec$^{-1}$ to 150uEm$^{-2}$ㆍsec$^{-1}$ quantum flux density. The stomatal opening of the abaxial surface began at lower irradiance and was completed earlier than the adaxial surface. The adaxial irradiances decreased in order of leaf position, flag, the 2nd, the 3rd leaf, and the stomatal resistances increased in the same order. Even under the same irradiance, the stomatal resistance of lower leaves were higher than those of upper leaves. The stomatal frequencies of lower leaves were less, but the stomatal size was greater than those of upper leaves. Consequently, the relative leaf area occupied by stomatal pores were constant among leaf positions in two species.

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태양전지 변환효율 보정계수 도입에 의한 태양발전시스템 발전량 예측 (Photovoltaic System Output Forecasting by Solar Cell Conversion Efficiency Revision Factors)

  • 이일룡;배인수;심헌;김진오
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제54권4호
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    • pp.188-194
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    • 2005
  • There are many factors that affect on the system output of Photovoltaic(PV) power generation; the variation of solar radiation, temperature, energy conversion efficiency of solar cell etc. This paper suggests a methodology for calculation of PV generation output using the probability distribution function of irradiance, PV array efficiency and revision factors of solar cell conversion efficiency. Long-term irradiance data recorded every hour of the day for 11 years were used. For goodness-fit test, several distribution (unctions are tested by Kolmogorov-Smirnov(K-S) method. The calculated generation output with or without revision factors of conversion efficiency is compared with that of CMS (Centered Monitoring System), which can monitor PV generation output of each PV generation site.

맑은 날 한낮의 사면 기온분포와 일사 수광량 간 관계 (Distribution of Midday Air Temperature and the Solar Irradiance Over Sloping Surfaces under Cloudless Condition)

  • 김수옥;윤진일
    • 한국농림기상학회지
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    • 제15권4호
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    • pp.291-297
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    • 2013
  • 소규모 집수역에서 한낮 기온의 분포와 일사수광량 간 관계를 관찰하기 위해 고도 50m급 3곳, 100m급 3곳, 300m급 3곳 등 9지점의 사면에 경사향을 달리하여 무인기상관측기를 설치하고 1년간 매일 1500 기온과 직전 4시간(1100-1500) 일사량자료를 수집하였다. 운량이 0인 맑은 날에 한정하여 각 지점의 사면 일사수광량을 계산하고 1500 기온과 비교하였다. 이때 각 지점의 경사도(slope)와 경사향(aspect)은 $30{\times}30$ m 격자를 기준으로 반경이 5, 10, 15, 20, 25, 30개 격자로 평활화 하여 사용하였다. 1500 기온에 미치는 직전 4시간 일사수광량 간에는 통계적으로 유의한 회귀관계가 인정되었으며, 반경 25개 격자(750m)로 평활화한 경우 사면 기온변이의 54%를 설명할 수 있었다(y = 0.8309x + 0.0438, $r^2$ = 0.5444).