• Proceedings of the KIPE Conference
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• 2016.07a
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• pp.469-470
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• 2016

Since efficiency of maximum power point tracking (MPPT) is important for photovoltaic systems, a number of MPPT algorithms have already been researched for other environment, however, the most of MPPT algorithms can't track maximum point in dynamic irradiation. In this paper, P&O and 3-Point MPPT which is more specialized in dynamic irradiation are compared in basis of European Efficiency Test(EN50530). The efficiency of 3-Point MPPT algorithm is proved by simulation and experiment. In result, 3-Point MPPT shows higher efficiency in dynamic irradiation and less affected by environment than P&O.

• 한국신재생에너지학회:학술대회논문집
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• 2005.11a
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• pp.595-598
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• 2005

The thermal performance of glass evacuated tube solar collectors are numerically and experimentally investigated. Four different shapes of solar collectors are considered and the performances of these solar collectors are compared. Dealing with a single collector tube, the effects of not only the shapes of the absorber tube but also the incidence angle of solar irradiation (beam radiation) on thermal performance of the collector are studied. However the solar irradiation consists of the beam radiation as well as the diffuse radiation. Also, the interference of solar irradiation and heat transfer interaction between the tubes exist in an actual solar collector. These effects are considered in this study experimentally and numerically the accuracy of the numerical model is verified by the experimental results. The result shows that the thermal performance of the absorber used a plate fin and U-tube is the best.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.119-120
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• 2011

본 논문에서는 전력공급자와 소비자가 양방향으로 실시간 정보를 교환해 에너지효율을 최적화시키는 지능형전력망 구축에 필요한 기술을 실현하기위해, 유무선 네트워크 기술을 기반으로 태양광전원 시스템에서 나오는 데이터값을 실시간 모니터링할 수 있는 원격 감시장치를 제작하였다. 이 장치는 유무선 네트워크를 이용해서 수용가 측에서 실시간 공급받고 있는 전압, 전류 뿐 아니라 역률, 온도, 일사량까지도 유무선 공유기 및 HMI소프트웨어를 통해 확인 할 수 있는 시스템을 제작하였다.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.113-114
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• 2011

PV(Photovoltaic)는 일사량 및 온도에 의해 얻을 수 있는 최대 전력이 변화하고, PV의 전압에 따라 출력 전력이 변화한다. 따라서 PV를 이용한 인버터는 최대 전력점에서 동작하게 하는 최대 전력점 추정(Maximum Power Point Tracking) 제어시스템이 필요하다. 본 논문에서는 인버터 제어에 필요한 여러가지 MPPT 기능 실험이 가능하게 하는 저가형 태양전지 시뮬레이터 시스템의 제어알고리즘을 제안한다. 이 시스템은 PV의 출력특성에 따른 출력값을 설정하고, 다양한 출력특성 변화의 실시간 변화가 가능하게 하는 새로운 알고리즘을 적용하였다. 이를 통해 PV가 설치되지 않은 곳에서 인버터의 MPPT 성능 시험이 가능하며, 실제 인버터에 구현된 P&O-MPPT와 연동하여 제안된 제어기법의 타당성을 검증하였다.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1084_1085
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• 2009

This paper proposes a novel maximum power point tracking(MPPT) control algorithm considering insolation to improve efficiency of PV system. The propoed algorithm is composed perturb and observe(PO) method and constant voltage(CV) method. PO method is simple to realize and CV method is possible to tracking MPP with low insolation. Response characteristics of proposed algorithm is compared to conventional PO method with insolation variation. This paper proves the validity of proposed algorithm through the analysis result.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.67.2-67.2
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• 2011

It is necessary to estimate empirical constants in order to predict the monthly mean daily global radiation on a horizontal surface in the developing areas for alternative energy. Therefore many different equations have proposed to evaluate them for certain areas. In this work a new correlation has been made to predict the solar radiation for any areas over Korea by calculating the regression models taking into account latitude, percentage of possible sunshine, and cloud cover. From the results, the single linear equation proposed by using percentage of possible sunshine method shows reliable results for estimating the global radiation with average annual deviation of -3.1 to +0.6 % from measured values.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.521-525
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• 2009

Solar, as an ideal renewable energy, has inexhaustible, clean and safe characteristics. However, solar energy is an extreme intermittent and inconstant energy source. In order to improve the photovoltaic system efficiency and utilize the solar energy more fully, and the DC current vary with the irradiation, it is necessary to study the characteristics of photovoltaic I-V according to the external factors. This paper presents the analysis of characteristics of photovoltaic I-V according to the irradiation. The results show that the DC current of the photovoltaic system are increased along with the increasing values of irradiation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.10
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• pp.38-46
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• 2011

Recently, interests in renewable energy have gradually increased. Of various renewable energy, Photovoltaic system has the properties affected by weather. This paper discusses the economic evaluation based on insolation data analysis. Real insolation data were obtained by radiation measurement device installed in projected photovoltaic system site during 20 months. Obtained real insolation data were standardized using clear day analysis. Standardized data are greater than obtained real insolation data and were used as parameters of RETScreen for the economic evaluation. In results, capacity(30[kW]) of soon cheon is shown the most B/C(1.20). Applied methods have effectively done to develop photovoltaic system.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.14 no.3
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• pp.15-20
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• 2018

To study the effects of solar energy in a greenhouse, outdoor air temperature and wind speed on inside air temperature, a simulation model for forecasting the greenhouse air temperature was conducted on the basis of the energy and mass balance theory. Application of solar energy to the greenhouse is major area in the renewable energy research and development in order to save energy. Recently, considering the safety and efficiency of the heating of greenhouse, clean energy such as geothermal and solar energy has received much attention. The analysed greenhouse has $50m^2$ of ground area which located in jocheon-ri of Jeju Province. Experiments were carried out to collect data to validate the model. The results showed that the simulated air temperature inside a plastic greenhouse agreed well with the measured data.

• Proceedings of the KIEE Conference
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• 2009.04a
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• pp.189-191
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• 2009

In this thesis, output voltage, current and power of solar module were classified by irradiation and module temperature from data of overall operating characteristics collected for one year in order to manage efficient photovoltaic generation system and deliver maximum power. In addition, from these data, correlations between irradiation, module temperature of photovoltaic cell and amount of power given by photovoltaic cell was quantitatively examined to deduce optimization of the design and construction of photovoltaic generation system. The results of this thesis can be summarized as follows. As output power characteristics according to a irradiation range of $100{\sim}900[W/m^2]$, output power was increased with increasing irradiation. This result corresponds well to the related equation on irradiation and output power.