• Current Photovoltaic Research
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• 제7권3호
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• pp.65-70
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• 2019

As a demand of higher power photovoltaic modules, shingled, multi-busbar, half-cell, and bifacial techniques are developed. Multi-busbar module has advantage for large amount of light havesting. And, half-cell is high power module for reducing resistive losses and higher shade tolerance. Recently, researches on multi-busbar is focused on reliability according to adhesion and intermetallic compound between Sn-Pb solder and Ag electrode. And half-cell module is researched to comparing with full-sized cell module for structure difference. In this study, we investigated the factors affecting to efficiency and adhesion of multi-wires half-cell module according to wire thickness, solder thickness, and flux. The results of solar simulator and peel test was that peel strength and efficiency of soldered cell is not related. But samples with flux including high solid material showed high efficiency. The results of FE-SEM and EDX line scan on cross-section between wire and Ag electrode for different flux showed thickness of solder joint between wire and Ag electrode is increasing through solid material increasing. Flux including high solid material would affect to solder behavior on Ag electrode. Higher solid material occurred lower growth of IMC layer because solder permeate to sider of wire ribbon than Ag electrode. And it increased fill factor for high efficiency. In soldering process, amount of solid material in flux and solder thickness are the factor related with characteristic of soldered photovoltaic cell.

• 센서학회지
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• 제22권6호
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• pp.433-438
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• 2013

In this paper, we found surface shapes are affected by several parameters of RIE, such as RF power, pressure, temp, and process times. The reflectance of pyramid and half sphere structures show differences among shapes, size, height, and depth of those structures. We made about $1{\mu}m$ pyramid and half sphere shapes of silicon surface with RIE. For comparing the reflectance, pyramid and half sphere structures are fabricated with same height. Pyramid structure cell shows higher cell efficiency of 12.5% by 1.1% than one of half sphere structure of 11.4%. The light absorption is more increased through the pyramid structure than half sphere structure.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권2호
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• pp.53-61
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• 2004

Characteristics of half cells of graphite/lithium and LiCoO$_2$/lithium, and full cells of graphite/LiCoO$_2$/ were analyzed by the use of GISOC(the gradual increasing of the state of charge). GISOC analyses generated IIE(the initial intercalation efficiency), which represents lithium intercalation property of the electrode material, and IIC$_{s}$(the initial irreversible capacity by the surface), which represents irreversible reaction between the electrode surface and electrolyte. Linear-fit range of graphite and LiCo/O$_2$electrodes were respectively 370 and 150 mAh/g based on material weight. IIE of graphite and LiCo/O$_2$electrodes were respectively 93∼94 % and 94∼95 %, and IICs of graphite and LiCo/O$_2$electrodes were 15∼17 mAH/g and 0.3∼1.7 mAh/g, respectively. IIE of graphite/LiCo/O$_2$full cell for GX25 and DJG311 as graphite showed 89∼90 %, which IIE value was lower than IIE of half cell of the cathode and the anode. Parameters of IIE and IIC$_{s}$ can also be used to represent not only half cell but also full cell. The characteristics of the full cell can be simulated through the correlative interpretation of potential profile, IIE, and IIC$_{s}$ of half cells.cells.

• Journal of Power Electronics
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• 제8권3호
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• pp.239-247
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• 2008

This paper presents the design of 1 kW prototype high frequency link boost half bridge inverter-fed DC-DC power converters with bridge voltage-doublers suitable for small scale PEM fuel cell systems and associated control schemes. The operation principle of this converter is described using fuel cell modeling and some operating waveforms. The switching mode equivalent circuits are based on simulation results and a detailed circuit operation analysis at soft-switching conditions.

• Journal of Information Display
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• 제1권1호
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• pp.48-51
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• 2000

In this work, we proposed a reflective antiferroelectric liquid crystal display (AFLCD) using a half-wave cell whose inplane tilt angle is $22.5^{\circ}$. To check the validity of our design, we fabricated a reflective half-wave AFLC cell of which inplane tilt angle is $24.9^{\circ}$, and measured VIS reflection spectra, contrast ratio and response time. In the results, the half-wave AFLC cell in the reflective configuration exhibits high brightness, high contrast ratio of 20:1, and fast response time of $700{\mu}s$.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.3-4
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• 2014

There is high probability of steel corrosion on the reinforced concrete exposed to marine environment by penetration of chloride ion. When making concrete structure with slag as admixture in marine environment, salt damage can be prevented. Therefore, this paper presents experimental results of steel corrosion resistance of slag concrete considering marine environment through half-cell potential method which is one of the nondestructive test. As a result of half-cell potential experiment, it was assumed that every specimen exposed to marine environment was not corroded, and as a result of destroying specimens, it was confirmed that there was no corrosion in specimens.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 전력전자학술대회 논문집
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• pp.518-519
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• 2012

This paper suggested a fuel cell generation system which combined interleaved full-bridge converter with half-bridge inverter. High ratio step-up converter is essential to use the power as general voltage source. Full-bridge converter has high efficiency and can boost the input voltage to high output with transformer. With series connected capacitors, interleaved full-bridge converter and half-bridge inverter are combined. Half-bridge inverter has two fewer switches compared to full-bridge type. Also, switching loss can be reduced. The performance is verified through simulation with 1.5[kW] fuel cell generation system.

• 한국화재소방학회논문지
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• 제14권1호
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• pp.22-26
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• 2000

비상시 또는 화재발생시에 인명의 원활한 대피를 위한 피난유도설비는 매우 중요하다. 이중 유도등은 상시점등되어 있어야할 뿐만 아니라 비상전원이 필요하므로 경제적 손실이 커지게 된다. 본 연구에서는 태양전지, 쵸퍼, 인버터로 태양광발전시스템을 구성하여 태양광으로부터 발생되는 에너지를 축전지에 저장시킨 후, half-bridge 인버터를 이용하여 상용전원없이 유도등이 점등되도록 제어하였다. 그 결과 상용전원으로 유도등 점등시와 제안한 시스템에 의한 유도등 점등결과가 동일함을 입증하고 그 유용성을 확인하였다.

• 전력전자학회논문지
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• 제10권1호
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• pp.78-86
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• 2005

최근 들어, 저전압·대전류 출력 특성을 갖는 연료전지를 위한 새로운 발전시스템이 주목받고 있다. 연료전지 발전시스템에서는 dc-dc 승압용 컨버터와 dc-ac 인버터가 필요하다. 그러므로 본 논문에서는 연료전지 발전시스템을 위한 ZVS 동작을 가진 dc-dc 능동 클램프 전류형 하프 브리지 컨버터를 제안하였다. 제안된 컨버터는 일반적인 dc-dc 컨버터에 비해 높은 효율과 높은 소자 이용율을 가진다. 연료전지 발전시스템은 연료전지(PEMFC)의 낮은 전압(28∼43[Vdc])을 380[Vdc]로 승압하기 위한 능동 클램프 전류형 하프 브리지 컨버터로 구성하였다. 단상 풀 브리지 인버터는 220[Vac], 60[Hz] 교류 출력을 얻기 위해 적용하였다.

• 한국전기전자재료학회논문지
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• 제36권2호
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• pp.136-142
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• 2023

In the past, the efficiency of solar cells had been increased in order to increase the efficiency of solar modules. However, in recent years, in order to increase output in the solar industry and market, the competitiveness of solar cells based on large-area solar cells and multi-bus bar has been increasing. Multi-busbar solar module is a technology to reduce power loss by increasing the number and width of the front busbar of the solar cell and reducing the current value delivered by the busbar by half through half-cutting. In the case of the existing M2 (156.75×156.75 mm²) solar cell, even with a half-cut, power loss could be sufficiently reduced, but as the area of the solar cell is enlarged to more than M6 (166×166 mm²), the need for more divisions emerged. This affected not only solar cells but also inverters required for module array configuration. Therefore, in this study, the electrical characteristics of a large-area solar cell and after division were extracted using Griddler simulation. The output characteristics of the module were predicted by applying the solar cell parameters after division to PSPice, and a guideline for the large-area solar module design was presented according to the number of divisions of the large-area solar cell.