• 조명전기설비학회논문지
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• 제20권4호
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• pp.21-28
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• 2006

본 논문에서는 Ballard사의 1.2[kW]급 연료전지와 연료전지의 저전압($28{\sim}43[VDC]$)을 승압(380([VDC])시키기 위한 풀-브리지 직류-직류 컨버터, 그리고 승압된 직류 링크전압을 교류 전압(220[VAC]), 60[Hz]으로 변환하기 위한 단상 풀-브리지 인버터로 구성된 연료전지 발전용 전력변환시스템 중 풀-브리지 고주파 절연형 영전압 영전류 스위칭 위상 천이 펄스폭 변조 직류-직류 컨버터를 제안하였다. 제안한 풀-브리지 고주파 절연형 영전압 영전류 스위칭 위상 천이 펄스폭 변조 직류-직류는 프리휠링 다이오드를 포함한 탭부 인덕터 필터를 이용하여 순환 전류를 저감시켰으며, 스위치 및 변압기의 턴-온, 턴-오프시에 오버슈트 전압이나 과도현상이 발생하지 않는다. 그리고 넓은 출력 전압 조정에도 효율을 $93{\sim}97[%]$정도 얻을 수 있으며, 출력 부하전류의 변화에 대해 거의 일정한 출력 전압 특성을 가졌다.

• 한국수소및신에너지학회논문집
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• 제19권6호
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• pp.529-536
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• 2008

Cyanobacteria Synechocystis PCC 6803 or the extracted thylakoid membrane from this strain was appled to photosynthetic bio-electrochemical fuel cell(PBEFC) for the production of hydrogen under the illumination of 48Klux using halogen lamp. PBEFC was composed of anode, cathode and membrane between them. Electrode material was carbon paper while electron mediator and receptor were added phenazine methosulfate(PMS) and potassium ferricyanide respectively. When water and 50 mM tricine buffer and $300{\mu}M$ PMS were added to the anode under the light condition, PBEFC produced the current density $4.4{\times}10^{-5}\;mA/cm^2$, $1.4{\times}10^{-4}\;mA/cm^2$ and $2.4{\times}10^{-4}\;mA/cm^2$, respectively. And the addition of the thylakoid membrane to the system increased current density to $1.3{\times}10^{-3}\;mA/cm^2$. Two times increase of the thylakoid membrane into the anode doubled the current density to $2.6{\times}10^{-3}\;mA/cm^2$. But the current density was not increased proportionally to the amount of thylakoid membrane increased. The system was unstable to measure the electricity output due to the foam production in the anode. Addition of triton X-100 and tween 80 stabilized the system to measure the electricity output but the current density was not increased higher than $8.4{\times}10^{-4}\;mA/cm^2$ and $2.3{\times}10^{-3}\;mA/cm^2$. When the thylakoid membrane was substituted to Synechocystis PCC 6803 cells of four-day culture which has chlorophyll contents $20.5{\mu}g/m{\ell}$, maximum current density was $1.3{\times}10^{-3}\;mA/cm^2$ with $1\;k{\Omega}$ resistance.

• 한국연소학회지
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• 제19권3호
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• pp.44-52
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• 2014

Solid oxide fuel cell(SOFC) makes electric power using hydrogen or reformed from methane and emits high temperature products that contain flammable species like hydrogen, carbon monoxide and methane which varies with operation condition. SOFC/gas turbine integrated system which uses thermal and chemical energy of the discharges is more efficient than SOFC itself. Burning character of the SOFC products will affect the efficiency and stability of the system. Experiments were conducted to know the characteristics of the flame for two typical composition of SOFC products, i.e. start-up and steady state composition. When coflowing air temperature was higher than $600^{\circ}C$, auto-ignitin occurred for both fuels. Though start-up fuel has higher contents of hydrogen, it makes longer flame than steady state composition. It was inferred that the amount of oxidizer necessary to burn makes this phenomenon. Steady state composition fuel was unstable since it contains lots of water. Nozzle that had 6 holes, distance between each hole was 16.7 times of hole diameter, improved the stability of the flame.

• Environmental Engineering Research
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• 제19권4호
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• pp.363-367
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• 2014

One chambered sediment microbial fuel cell (SMFC) was equipped with Fe, brass (Cu/Zn), Fe/Zn, Cu, Cu/carbon cloth and graphite felt anode. Graphite felt was used as common cathode. The SMFC was membrane-less and mediator-less as well. Order of anodic performance on the basis of power density was Fe/Zn ($6.90Wm^{-2}$) > Fe ($6.03Wm^{-2}$) > Cu/carbon cloth ($2.13Wm^{-2}$) > Cu ($1.13Wm^{-2}$) > brass ($Cu/Zn=0.24Wm^{-2}$) > graphite felt ($0.10Wm^{-2}$). Fe/Zn composite anode have twisted 6.73% more power than Fe alone, Cu/carbon cloth boosted power production by 65%, and brass (Cu/Zn) produced 65% less power than Cu alone. Graphite felt have shown the lowest electricity generation because of its poor galvanic potential. The estuarine sediment served as supplier of oxidants or electron producing microbial flora, which evoked electrons via a complicated direct microbial electron transfer mechanism or making biofilm, respectively. Oxidation reduction was kept to be stationary over time except at the very initial period (mostly for sediment positioning) at anodes. Based on these findings, cost effective and efficient anodic material can be suggested for better SMFC configurations and stimulate towards practical value and application.

• 공업화학
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• 제24권6호
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• pp.567-578
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• 2013

미생물연료전지는 혐기성 조건에서 미생물의 촉매 반응을 통해 유기물질의 화학에너지를 전기에너지로 변환하는 생물전기화학 장치이다. 미생물연료전지의 전력밀도 및 쿨롱효율은 산화전극 챔버 내 미생물의 종류, 시스템 구성요소 및 운전조건에 영향을 받는다. 미생물연료전지에서 달성할 수 있는 전력은 구성요소, 물리적 및 화학적 운전조건, 바이오 촉매 선택 등의 최적화로 디자인을 변형하여 현저하게 증가시킬 수 있다. 본 총설에서는 미생물연료전지의 구성, 운전 매개변수의 최적화 및 성능과 더불어 장래 응용에 대한 최근 연구를 중점적으로 고찰하고자 한다.

• 한국수소및신에너지학회논문집
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• 제30권2호
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• pp.136-146
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• 2019

A solid oxide fuel cell (SOFC) based hybrid desiccant cooling system model is developed to study the effect of fuel utilization rate of the SOFC on the reduction of energy consumption and $CO_2$ emission. The SOFC-based hybrid desiccant cooling system consists of an SOFC system and a Hybrid desiccant cooling system (HDCS). The SOFC system includes a stack and balance of plant (BOP), and HDCS. The HDCS consists of desiccant rotor, indirect evaporative cooler, electric heat pump (EHP), and heat exchangers. In this study, using energy load data of a commercial office building and SOFC-based HDCS model, the amount of ton of oil equivalent (TOE) and ton of $CO_2$ ($tCO_2$) are calculated and compared with the TOE and $tCO_2$ generation of the EHP using grid electricity.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.730-734
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• 2007

National projects on renewable energy and new energy are driven more actively than ever in many countries for the exhaustion of fossil fuel energy from the turn of the century. Such activities began to spread out in railway industry with centering around west European countries. Electric energy is generated on the hybrid vehicle itself, which contributes to reduction of the cost for construction of the infrastructure required for the supply of electric power. Hybrid tram is mainly composed of propulsion system to control electric energy, automatic guidance system to control steering and operation, and central vehicle unit to control and monitor major electronic devices. Generation and supply of electric power are made by the combination of engine generator and battery, or fuel cell and super capacitor.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2011년도 추계학술대회
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• pp.283-284
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• 2011

연료전지는 다른 대체에너지원에 비해 효율이 높고 소음이 거의 없으며 친환경적이라는 장점으로 인해 각광받고 있다. 연료전지는 수소와 산소의 전기화학반응으로 물이 생성되는데, 이때 전기와 열이 발생한다. 또한, 저전압 대전류의 특성을 가지며 부하에 따른 출력전압의 변동이 크므로 전압을 조정해야 한다. 따라서 저전압을 승압하기 위한 DC/DC Boost(이하 부스트)컨버터가 필요하다. 본 논문에서는 연료전지를 이용한 배터리 충전 시스템을 구성하고, 그 기능을 MATLAB/SIMULINK의 모델과 시뮬레이션을 통해 확인한다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2011년도 전력전자학술대회
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• pp.74-75
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• 2011

EBOP(Electrical Balance of Plant)는 연료전지 출력인 DC 전원을 전력변환기술을 이용하여 계통 전원에 연계하는 계통 연계 인버터 시스템이다. 포스코파워에서 개발한 3MW급 EBOP 시스템은 국제 규격(IEEE std.1547, UL1741)에 의한 성능 검증 시험을 거치고 국내 2개 현장에 5기를 적용하여 운전 중이다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.268-269
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• 2007

본 논문은 여러 컨버터 토플로지 중 연료전지의 특성에 맞는 컨버터를 선정하고 인버터 설계를 통하여 연료전지용 PCS시스템을 구현하였으며 시뮬레이션을 통하여 검증하였다.