• Journal of Hydrogen and New Energy
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• v.17 no.3
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• pp.279-285
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• 2006

Recirculation for the unreacted fuel is necessary to improve the overall efficiency of the fuel cell system and to prevent fuel starvation since the fuel cell for a vehicle application is a closed system. In case of the automotive fuel cell, the ejector which does not require any parasitic power is good for the performance improvement and easy operation. It is essential to design the customized ejector due to the lack of the commercial ejector corresponding to the operating conditions of the fuel cell systems. In this study, the design methodology for the ejector customized to an automotive fuel cell is proposed. The model based sensitivity analysis prevents the time-consuming redesign and reduces the cost of developing ejector. As a result, the customized ejector to meet the desired performance within overall operating range has developed for the PEMFC automotive system.

• Journal of Hydrogen and New Energy
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• v.31 no.6
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• pp.522-529
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• 2020

This study evaluated the effect of improving the atmospheric environment based on the premise that the supply of hydrogen fuel cell vehicles (HFCV) will be achieved as many as the number of vehicles presented in the hydrogen economy activation roadmap announced by the Korean government in January 2019. The HFCV supply target (2.7 million passenger cars) suggested in the hydrogen economy revitalization roadmap was logically allocated to the five major metropolitan areas in Korea. Air pollution damage costs by region were calculated by reflecting the basic unit of damage cost to the estimated air pollutant emissions. As a result, it was confirmed that the benefits per unit of some cities in Gyeonggi-do were derived more than major cities in the metropolitan area.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.1
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• pp.7-14
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• 2014

The core of the automotive industry's strategy to handle the climate change can be explained as the development and distribution of the vehicles with high fuel efficiencies and low emission. Clean Diesel, hydrogen fuel cell, electric, and especially hybrid power-train vehicles have been actively studied. This paper dynamically analyzes the performance of a hybrid system's five driving modes. The research subject consists of one engine, two electric motors, two simple planetary gears, and one compound planetary gears with five clutches. To define the steady state equation of the system, interaction formulas of five driving modes are introduced with motion variables and torque variables. These formulas are then used to analyze the speeds, torques, and power flows of each mode.

• New & Renewable Energy
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• v.1 no.3 s.3
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• pp.42-50
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• 2005

This paper deals with the economic feasibility model and analysis of a hydrogen fuel-cell vehicle [FCV] against two similar types of non-business vehicles fueled with gasoline [GV] and diesel [DV] considering greenhouse gas [GHG]. Considering the price of vehicles and annual operating cost, we build a classical economic feasibility model. Since the economic feasibility could be affected by many input factors such as the prices of vehicles, the price of fuels, annual driving distance and so on, we estimate the average future values of input factors, which is defined as "the average case". Based on the average case, we assess the representative economic feasibility of a FCV with/without GHG, and by changing various annual driving distances, we assess its economy in terms of net-present value, internal rate of return, and payback period. In addition, we make some sensitivity analysis of its economic feasibility by changing the values of the critical input factors one at time. Based on the average case, it turns out that the consumer of a FCV could save 25,000 won/year for a GV, but the consumer could pay 120,000 won/year more for a DV. This indicates that gasoline vehicles could be replaced gradually by FCVs in Korean market which might be formed by those consumers driving annually more than approximately 14,800 km. As the results of our sensitivity analysis, it turns out that a FCV is no more economical if the difference of the prices between FCV and GV is more than 10,130,000 won or the price of hydrogen fuel could be more than 5,136 won/kg.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.209-212
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• 2009

수소에너지의 무궁한 가능성 때문에 관련 기술은 미래 국가 경쟁력을 좌우할 것이며, 이러한 수소에너지의 핵심으로 수소제조공정 및 수소스테이션 관련 기술은 국가연료전지 시장을 비롯한 수소연료전지자동차 산업 전반에 커다란 영향을 미칠 것으로 예상되고 있다. 그러므로 세계 각국은 수소에너지를 미래에너지원으로 개발하기 위하여 대규모로 기술개발 및 실증연구를 실시하고 있으며, 주로 수소연료전지자동차 개발과 아울러 수소스테이션 개발에 대한 인프라 구축에 대해 이루어지고 있다. 국내에서도 국가주도로 수소스테이션 건설이 이루어지고 있으며, 본 연구에서는 수소연료전지자동차를 이용하여 수소인프라와의 모니터링에 대한 현황에 대해 논의하고자 한다.

• Journal of Hydrogen and New Energy
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• v.23 no.6
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• pp.588-597
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• 2012

In the present study, the dispersion characteristics of hydrogen leakage from a Fuel Cell Vehicle (FCV) were analyzed by numerical simulation in order to assess the risk of a hydrogen leakage incident in a long road tunnel. In order to implement the worst case of hydrogen leakage, the FCV was located at the center of a tunnel, and hydrogen was completely discharged within 63 seconds. The Leakage velocity of hydrogen was adopted sub-sonic speed because that the assumption of the blockage effect of secondary device inside a vehicle. The temporal and spatial evaluation of the hydrogen concentration as well as the flammable region in a road tunnel was reported according to change of ventilation operating conditions. The hydrogen was blended by supply air form a ventilation fan, however, the hydrogen was discharged to outside in the exhaust air. It is observed that the efficiency way to eliminate of hydrogen is supply air operating condition under the hazardous hydrogen leaking incident. The present numerical analysis can be provided useful information of ventilation under the hydrogen leaking situation.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.179-185
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• 2005

Nowadays, study about hydrogen fuel which consist of hydrogen extraction process, reforming, fuel cell equipment, and receptacle are flourish all over the world. Currently, Korea hydrogen station is still underdevelopment. Yet the most important part such as hydrogen compressor has not been develop. Therefore, if the high pressure compressor for hydrogen have been developed by domestic technology. In the future many benefit can be gain instead of importing. Such as many hydrogen station can be built in Korea, and also Korea will be able to provide hydrogen system for worldwide. This study is going to analysis hydrogen compressor in order to store high pressure hydrogen. This is almost approach practical use of tile hydrogen storage method.

• Applied Chemistry for Engineering
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• v.30 no.6
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• pp.687-693
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• 2019

As the hydrogen fuel cell market is expanded starting from hydrogen electric vehicle and power generation field, the demand for fuel cells and hydrogen increases recently. Therefore, research works on fuel cell durability and fuel efficiency are required in order to activate the fuel cell market and commercialization. A dead-ended anode system was used in this study to optimize the fuel cell performance and fuel efficiency. The effect of purge condition according to the applied current and hydrogen supply pressure on the fuel cell performance were evaluated. In addition, the influence of water back diffusion on the different electrolyte membrane thickness was analyzed. The accumulated water was purged with a solenoid valve in the case of 3% voltage decrease in the dead-ended anode system. The experiment was performed with the hydrogen supply pressure of 0.1~0.5 bar and purge duration of 0.1~1 second. A maximum fuel efficiency of 98.9% was achieved under the purge duration of 0.1 s and hydrogen supply pressure of 0.1 bar with a NR 211 (25.4 um) membrane. However, the fuel cell performance decreased in a long-term operation due to some frequent flooding. The fuel efficiency and purge interval increased due to decreased back diffusion rates of the water and nitrogen with a NR 212 (50.8 um) membrane.

• 한국전기화학회:학술대회논문집
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• 2005.07a
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• pp.351-354
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• 2005

• Journal of Hydrogen and New Energy
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• v.21 no.3
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• pp.149-157
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• 2010

The electromagnetic characteristics of FCEVs (fuel cell electric vehicles) are much different from the existing combustion engine cars as well as hybrid, plug-in-hybrid, and pure electric vehicles due to the high voltage/current generated by a fuel cell stack which uses a compressed hydrogen gas reacted with oxygen. To operate fuel cell stack efficiently, BOP (Balance of Plant) is essential. BOP systems are used many not only for motors in water pump, air blower, and hydrogen recycling pump but also inverters for these motors. Since these systems or components are connected by high voltage cables, EMC (Electromagnetic compatibility) analysis for high voltage/current cable is the most important element to prevent the possible electric functional safety errors. In this paper, electromagnetic fields of high current/voltage cable for FCEVs is studied. From numerical analysis results, time harmonic magnetic field strength of high current/voltage cable have difference of 20～28 dB according to phase. EMI result considered ground effect of FECV at 10 m shows difference of 14.5 dB at 30 MHz and 2.8 dB at 230 MHz compared with general cable.