• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1404-1404
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• 2011

Shortage of fossil fuel energy makes current industry to find a new energy sources. One of the solutions is using the renewable energy sources like wind, sun, water, and so on. If we think with flex idea, the existing PV system's role can be greatly changed. So in this paper, I want to suggest some ideas for PV systems as one of outstanding energy source. The specific and technical explanation will be shown in the following paper in detail.

• 산업공학
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• 제25권4호
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• pp.441-449
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• 2012

Solar PV(photovoltaic) is paid great attention to as a possible renewable energy source to overcome recent global energy crisis. However to be a viable alternative energy source compared with fossil fuel, its market competitiveness should be attained. Grid parity is one of effective measure of market competitiveness of renewable energy. In this paper, we forecast the grid parity timing of solar PV energy in Korea using two factor learning curve model. Two factors considered in the present model are production capacity and technological improvement. As a result, it is forecasted that the grid parity will be achieved in 2019 in Korea.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2010년도 추계학술대회
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• pp.246-247
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• 2010

This paper proposed a method for controlling the active power of a single-phase grid-connected photovoltaic(PV) system by the quasi-Z-source inverter (QZSI). The MPPT of PV array is achieved by adjusting a shoot-through time of QZSI. The PI+R controller is used for reducing the steady-state error of the grid current. The simulation studies are carried out to verify the performances of proposed system.

• 설비공학논문집
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• 제26권12호
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• pp.559-564
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• 2014

The development of photovoltaic-thermal (PVT) technology has been introduced in recent years specifically to increase PV efficiency. One of the characteristics of PV systems is that the electricity generation increases as the solar radiation increases whereas the efficiency decreases because of high surface temperatures. Using a photovoltaic-thermal system, the surface temperature can be decreased by capturing the excess heat and the efficiency can be increased due to these characteristics. In this paper, three cases are introduced : 1) PV_r as the reference case, 2) PVT_a, which uses air as a heat source, and 3) PVT_w, which uses water as a heat source. Experiments were performed, analyzed, and compared to examine the effect of the PVT type on the efficiency of the system. The results showed that ETC($%/^{\circ}C$) efficiency of the PVT cases was increased versus the reference case due to decreasing surface temperature. Total efficiencies, which are electrical efficiency and thermal efficiency, for each PVT are tested and found to be 12.22% for PV_r, 29.50% for PVT_a, and 68.74% for PVT_w.

• 전기학회논문지
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• 제65권8호
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• pp.1340-1346
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• 2016

Utilization of Distributed Generations (DGs) using Renewable Energy Sources (RESs) has been constantly increasing as they provide a lot of environmental, economic merits. In spite of these merits, some problems with respect to voltage profile, protection and its coordination system due to reverse power flow could happen. In order to analyze and solve the problems, accurate modeling of DG systems should be preceded as a fundamental research task. In this paper, we present a PhotoVoltaic (PV) generation system which consists of practical PV cells with series and parallel resistor and an inverter for interconnection with a main distribution system. The inverter is based on controllable current source which is capable of controlling power factors, active and reactive powers within a certain limit related to amount of PV generation. To verify performance of the model, a distribution system based on actual data is modeled by using ElectroMagnetic Transient Program (EMTP) software. Computer simulations according to various conditions are also performed and it is shown from simulation results that the model presented is very effective to study DG-related researches.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.1328-1331
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• 2002

Nowaday, almost of practical energy is come from the fossil fuel, such as coal, oil and gas those are limited and caused the environmental pollution. For these reason. solar energy is come into notice as a new alternative energy source to overcome the shortage of electricity in the $future^{(1)}$. In this paper, small PV system using photo sensor for tracking sun is developed and is verified by experiments.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.665-669
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• 2000

Recently the problem of energy branch become worse increasingly. Therefore many researches about new energy source are processing in several places around are processing in several places around the world. Especially solar energy has many advantages like as purity and infinity. Photovoltaic(PV) system can be classified into two types : One is stand alone type and the other is utility interactive one. Utility interactive type PV system need some technology that Maximum peak power tracking(MPPT) and Anti-islanding and Active Power filter(APF). For APF operation dc-link voltage should be high to supply sufficient output current which needed for harmonic current compensation so usually DC-DC converter is used for boost. In this paper DC-DC converter for PV system and controller for dc-link voltage control are analyzed and designed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.1290-1292
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• 2001

Photovoltaic(PV) power generation system has been extensively studied and watched with keen interest as a clean and renewable power source. On the other hand, because the output power of solar cell is not only unstable but uncontrollable, the maximum power point tracking(MPPT) control is still hot issue with the tracking failure left unsolved under the sudden fluctuation of irradiance. Hence, in this paper, we introduce the mechanism of the tracking failure under the fluctuation of irradiance, and show the simulation results using SPRW(simulation method for PV power generation system using real weather conditions).

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.185-187
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• 2008

This paper proposed design and development of a photo voltaic (PV) array fed induction motor drive. A drive system using a chopper circuit to track maximum power from the PV for different solar insolation and a current controlled voltage source inverter (CC-VSI) to optimally match the motor to PV characteristics is presented. The model equations governing interaction of torque and flux producing components of motor current with available solar power is developed for the operation of the system at optimum efficiency. Performance of the system is presented for different realistic operating conditions, which demonstrates its special features for applications such as solar water pumping system, solar vehicles and floor mills located in hilly and isolated areas.

• 한국미생물·생명공학회지
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• 제22권3호
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• pp.246-251
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• 1994

Pseudomonas syringae pv. tabaci(Pa45) Tox$^{-}$ cells were infected with phage Ps90 strain isolated form the natural source, and the Ps90 lysogenized bacterial cells were then obtained. The lyxohenized cells produced tabtoxin and the phage induction occured when the cells treated with mitomycin C. The Southren hybridization alnalysis of the four EcoRI-treated plasmid fragments and the EcoRI-digested genomic DNA of Tox$^{+}$ and Tox$^{-}$ strains using phage DNA as a probe showed that only those DNA fragment of Tox$^{+}$ strain were related to the Ps90 phage DNA. Based on these results, the tabtoxin producing DNA fragments of the bacteris are presumed to have originated from the same phage DNA, and to be responsible for the pathogenecity of the bactrial strains.