• Solar Energy
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• v.18 no.2
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• pp.1-17
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• 1998

In order to analyze the status of development of solar thermal technology in Korea, importance and characteristics of solar thermal technology is considered. That is, solar collector, solar hot water heater, solar industrial system and solar buildings is analyzed in the view of worldwide technology, And then, domestic insolation sources and sale amounts of solar system is introduced. In this paper, it Is presented long-term objective in the basic plan of development new & rowable energy in Korea. As a result of analysis, the status of solar thermal technology in Korea is pactical use state in the field of low temperature use and application state in the field of mid-temperature use.

• Proceedings of the KIEE Conference
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• 1998.07b
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• pp.822-824
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• 1998

The control of indoor illumination using fuzzy controller and sunlight is presented. Indoor illumination 220[lx] can be kept according as blind control with sunlight.

• Proceedings of the SAREK Conference
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• 2007.06a
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• pp.168-168
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• 2007

• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.2
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• pp.89-95
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• 2009

Tracking the Maximum Power Point(MPP) of a photovoltaic(PV) array is usually an essential part of a PV system. The problem considered by MPPT techniques is to find the voltage $V_{MPP}$ or current $I_{MPP}$ at which a PV array should operate to generate the maximum power output PMPP under a given temperature and irradiance. The MPPT control methods, such as the perturb and observe method and the incremental conductance method require microprocessor or DSP to determine if the duty cycle should be increased or not. This paper proposes a simple and fast analog MPPT method. The proposed control scheme will track the MPP very fast and its hardware implementation is so simple, compared with the conventional techniques. The new algorithm has successfully tracked the MPP, even in case of rapidly changing atmospheric conditions, and Has higher efficiency than ordinary algorithms.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.3
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• pp.141-148
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• 2021

Agrivoltaic systems, also called solar sharing, stated from an idea that utilizes sunlight above the light saturation point of crops for power generation using solar panels. It is expected that agrivoltaic systems can realize climate smart agriculture by reducing evapotranspiration and methane emission due to the reduction of incident solar radiation and the consequent surface cooling effect and bring additional income to farms through solar power generation. In this study, to evaluate that agrivoltaic systems are suitable for realization of climate smart agriculture, we conducted agro-environmental observations (i.e., downward/upward shortwave/longwave radiations, air temperature, relative humidity, water temperature, soil temperature, and wind speed) in a rice paddy under an agrivoltaic system and compared with the environment outside the system using automated meteorological observing systems (AMOS). During the observation period, the spatially averaged incoming solar radiation under the agrivoltaic system was about 70% of that in the open paddy field, and clear differences in the soil and water temperatures between the paddy field under the agrivoltaic system and the open paddy field were confirmed, although the air temperatures were similar. It is required in the near future to confirm whether such environmental differences lead to a reduction in water consumption and greenhouse gas emissions by flux measurements.

• Journal of the Korean Solar Energy Society
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• v.25 no.1
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• pp.35-44
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• 2005

The absorbing rate of solar irradiation on the surface of an absorbing tube in a glass evacuated solar collector is numerically investigated. Four different shapes of the absorbing tubes are considered, and the absorbed solar irradiation on the surface is calculated for several distances between the absorbing tubes and the incidence angle of solar beam radiation. From the calculation, it is known that the absorbing rate of solar irradiation on the tube surfaces depends upon the shape and the arrangement of absorbing tube and the incidence angle.

• Proceedings of the KIPE Conference
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• 2016.07a
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• pp.181-182
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• 2016

본 논문은 최대전력점 추종 제어기법의 성능 개선을 위한 독립형 태양광 발전시스템의 하이브리드 기법을 제안한다. 하나의 기법만을 사용하는 경우, 일사량 및 온도 조건에 따라 비선형적 출력특성을 갖는 태양전지의 최대출력점을 효율적으로 추종하기 어렵다. 제안한 방법은 가변 스텝 사이즈를 적용한 Perturb and Observe (P&O) 기법으로 과도상태의 추종성능을 보장하고, Incremental Conductance (InC) 기법으로 정상상태의 자려진동을 감소시켜 출력 전력의 효율을 높일 수 있다. 1.4kW 태양광 발전시스템을 모의하여 수행된 PSIM 시뮬레이션 결과로 제안한 알고리즘의 타당성을 검증하였다.

• Proceedings of the KIPE Conference
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• 2011.11a
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• pp.277-278
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• 2011

본 논문은 태양광발전의 주변 환경 변화에 종속적인 태양광 모듈 출력을 개선하기 위해 사용되는 두 개의 다른 형태의 태양광발전 시스템용 DC Optimizer에 대해 기술한다. 일사량 가변 및 외부 음영 조건 발생 시 서로 다른 두 유형의 DC Optimizer 동작 특성을 비교 분석하고 이를 시뮬레이션을 통해 검증한다.

• Proceedings of the KIEE Conference
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• 2006.04b
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• pp.358-361
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• 2006

태양전지는 일사량에 따라 그 출력특성이 변하기 때문에 전지로부터 최대출력을 얻기 위해서는 컨버터에 의한 최대 전력점 추종제어가 필요하다. 본 논문에서는 태양광 발전시스템의 최대전력추종을 위해 퍼지이론을 도입한 퍼지제어기를 설계하였다. 퍼지제어기의 디지털 설계를 위해 태양광 발전시스템을 각 부분을 구성하고, FPGA를 사용하여 제어기를 구현하였다. 또한 실험을 통해 FPGA의 퍼지제어기로서의 구현가능성을 발견하고 그 타당성을 입증하고자 한다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.55-56
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• 2011

화석연료의 고갈은 신재생 에너지의 개발을 가속화 시키고 있다. 태양광발전 역시 대체에너지원으로서 그 중요도가 점차 증가하고 있다. 하지만 일사량이나 기후변화 또는 계통연계 위치에 따라서 태양광 발전의 출력이 변동되어 고조파 성분이 계통으로 유입되면서 장치의 소손 원인이 되거나, 통신유도장해, 보호계전기 오동작 등의 문제점이 발생하고 있다. 따라서 본 논문은 EMTP를 이용하여 온도나 조사량이 변하여 태양광 발전의 출력 변동 시 배전계통으로 유입되는 고조파 성분을 분석하였다.