• Current Photovoltaic Research
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• v.6 no.2
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• pp.31-38
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• 2018

Multijunction solar cells present a practical solution towards a better photovoltaic conversion for a wider spectral range. In this review, we compare different types of multi-ijunction solar cell. First, we introduce thin film multijunction solar cell include to the thin film silicon, III-V material and chalcopyrite material. Until now the maximum reported power conversion efficiencies (PCE) of solar cells having different component sub-cells are 14.0% (thin film silicon), 46% (III-V material), 4.4% (chalcopyrite material) respectively. We then discuss the development of multijunction solar cell in which c-Si is used as bottom sub-cell while III-V material, thin film silicon, chalcopyrite material or perovskite material is used as top sub-cells.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.658-661
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• 2010

The application of solar energy with creation of new industry is becoming diversification together. In this paper, we implement power supply the system of the single module type using solar energy. Through the implementation, we improve performance of system and it will be able to use for a long time efficiently also in the place where the electrical supply is difficult.

• Current Photovoltaic Research
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• v.10 no.3
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• pp.90-94
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• 2022

The screen-printing method is the most mature solar cell fabrication technology, which has the advantage of being faster and simpler process than other printing technology. A front metallization printed through screen printing influences the efficiency and manufacturing cost of solar cell. Recent technology development of crystalline silicon solar cell is proceeding to reduce the manufacturing cost while improving the efficiency. Therefore, screen printing requires process development to reduce a line width of an electrode and decrease shading area. In this paper, we will discuss the development trend and prospects of screen-printing metallization using metal paste, which is currently used in manufacturing commercial crystalline silicon solar cells.

• Journal of the Korean Solar Energy Society
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• v.36 no.4
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• pp.31-40
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• 2016

The demands for photovoltaic systems on a large scale have grown dramatically and require new technologies to get the high efficiency and reliable operations of power conversion systems. These needs can be realized by the cost-effective and high performance digital revolutions and faster semiconductor switching devices. However, the new power systems have been more sophisticated and their reliability becomes critical issues. In this paper, a new fault-tolerance power conversion scheme for the photovoltaic systems is proposed. The proposed fault-tolerant scheme is able to supply energy from solar panels to loads intermittently in spite of a front boost converter open failure, and its voltage and current controllers are designed to improve the transient performance by using an average model design scheme. The proposed approach is verified both by simulations. The results will enable more timely and wide usage of alternative/renewable energy systems resulting in increased energy security.

• Journal of Construction Engineering and Project Management
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• v.3 no.3
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• pp.23-34
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• 2013

As climate change and environmental pollution become one of the biggest global issues today, new renewable energy, especially solar photovoltaic (PV) system, is getting great attention as a sustainable energy source. However, initial investment cost of PV system is considerable, and thus, it is crucial to predict electricity generation accurately before installation of the system. This study analyzes the loss ratio of solar photovoltaic electricity generation from the actual PV system monitoring data to predict electricity generation more accurately in advance. This study is carried out with the following five steps: (i) Data collection of actual electricity generation from PV system and the related information; (ii) Calculation of simulation-based electricity generation; (iii) Comparative analysis between actual electricity generation and simulation-based electricity generation based on the seasonality; (iv) Stochastic approach by defining probability distribution of loss ratio between actual electricity generation and simulation-based electricity generation ; and (v) Case study by conducting Monte-Carlo Simulation (MCS) based on the probability distribution function of loss ratio. The results of this study could be used (i) to estimate electricity generation from PV system more accurately before installation of the system, (ii) to establish the optimal maintenance strategy for the different application fields and the different season, and (iii) to conduct feasibility study on investment at the level of life cycle.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.104-109
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• 2009

If the Photovoltaic(PV) Module should get physical load, the PV module will be warped according to elongation of the front glass and then micro-crack will be occurred in the heat sealed Solar Cell. This micro-crack drops output of the short circuit current and the open circuit voltage of the PV Module. This is because of increase of resistance component by micro-crack. Micro-crack at specific Solar Cell in the module reduces the durability of PV Module such as less output, Hot-Spot in the PV module caused by Solar Cell output mismatch, heat generating as resistance component caused by micro-crack. In this study, among some factors which effect to the output of crystalline PV Module, we will see how the micro-crack caused by mechanical stress effects to the electrical output of PV Module.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.375-385
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• 2013

As climate change and environmental pollution become one of the biggest global issues today, new renewable energy, especially solar photovoltaic (PV) system, is getting great attention as a sustainable energy source. However, initial investment cost of PV system is considerable, and thus, it is crucial to predict electricity generation accurately before installation of the system. This study analyzes the loss ratio of solar photovoltaic electricity generation from the actual PV system monitoring data to predict electricity generation more accurately in advance. This study is carried out with the following five steps: (i) Data collection of actual electricity generation from PV system and the related information; (ii) Calculation of simulation-based electricity generation; (iii) Comparative analysis between actual electricity generation and simulation-based electricity generation based on the seasonality; (iv) Stochastic approach by defining probability distribution of loss ratio between actual electricity generation and simulation-based electricity generation ; and (v) Case study by conducting Monte-Carlo Simulation (MCS) based on the probability distribution function of loss ratio. The results of this study could be used (i) to estimate electricity generation from PV system more accurately before installation of the system, (ii) to establish the optimal maintenance strategy for the different application fields and the different season, and (iii) to conduct feasibility study on investment at the level of life cycle.

• KIPS Transactions on Computer and Communication Systems
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• v.5 no.10
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• pp.353-360
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• 2016

Recently, solar photovoltaic(PV) power generation which generates electrical power from solar panels composed of multiple solar cells, showed the most prominent growth in the renewable energy sector worldwide. However, in spite of increased demand and need for a photovoltaic power generation, it is difficult to early detect defects of solar panels and equipments due to wide and irregular distribution of power generation. In this paper, we choose an optimal machine learning algorithm for estimating the generation amount of solar power by considering several panel information and climate information and develop a defect detection system by using the chosen algorithm generation. Also we apply the algorithm to a domestic solar photovoltaic power plant as a case study.

• 한국태양에너지학회:학술대회논문집
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• 2011.11a
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• pp.297-302
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• 2011

In this study, used Trnsys and will apply metropolitan city distinguishes, fixations and BIPV systems the photovoltaic module arrangement environment which receives solar radiation quantity plentifully from the case design process which and most the outcome value simulation did analyzed. The climate data uses each metropolitan city distinguishes 20 average weather data, With measured values of horizontal solar radiation. The error scope appeared with 0.1%~6.7%. Variable of module arrangement Azimuth and angle of inclination of module and comparison group Module on due south direction angle of inclination $45^{\circ}$ day time set with the yearly average solar radiation quantity which receives. The result When the case comparison group which arranges a solar storehouse module with optimum environment and comparing until the minimum 1.4% - maximum 10.9% the solar radiation quantity difference appears with the thing, metropolitan city distinguishes considers the case solar radiation quantity which will arrange a photovoltaic module and that must establish with optimum environment judges.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.3
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• pp.491-498
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• 2020

Recently, In the production line of batteries, charge and discharge tests are essential to verify battery characteristics. In this case, the battery charging uses a unidirectional AC/DC converter capable of output voltage and current control, and the discharge uses a resistive load. Since this method consumes energy during discharge, it must be replaced with a bi-directional AC/DC converter system capable of charging and discharging. Although it is difficult to replace the connected inverter part of the bi-directional AC/DC converter system due to the high cost, the spread of the solar-connected inverter rapidly increases as the current solar supply business is activated, and thereby the solar-connected type Inverter prices are plunging. If it can be used as a power converter for battery discharge without program modification of the solar-powered inverter, it will have competition. In this paper, propose a new battery discharge system using a combination of a photovoltaic DC/DC simulator and photovoltaic PCS using a battery to be used as a power converter for battery discharge without program modification of a low-cost photovoltaic inverter. In addition, propose an optimal solar characteristic curve for the stable operation of PCS. The validity of the proposed system was verified using a 500[W] class solar DC/DC simulator and a solar PCS prototype.