• 한국자동차공학회논문집
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• 제14권5호
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• pp.65-72
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• 2006

In new generation vehicle technologies, a fuel cell vehicle becomes more important, by virtue of their emission merits. In addition, a fuel cell is considered as a major source to generate the electricity for vehicles in near future. This paper focuses on modeling of not only an electric vehicle and but also a fuel cell vehicle to estimate performances. And an EV cart is manufactured to verify the modeling. Speed, voltage, and current of the vehicle and modeling are compared to estimate them at acceleration test and driving mode test. The estimations are also compared with the data of the Ballard Nexa fuel cell stack. In order to investigate a fuel cell based vehicle, motor and fuel cell models are integrated in a electric vehicle model. The characteristics of individual components are also integrated. Calculated fuel cell equations show good agreements with test results. In the fuel cell vehicle simulation, maximum speed and hydrogen fuel consumption are estimated. Even though there is no experimental data from vehicle tests, the vehicle simulation showed physically-acceptable vehicle characteristics.

• 한국수소및신에너지학회논문집
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• 제28권5호
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• pp.492-501
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• 2017

A 900 W scale direct methanol fuel cell (DMFC) stack is designed and fabricated for unmanned aerial vehicle (UAV) applications. To meet the volume and weight requirements, metallic bipolar plates are applied to the DMFC stack for the first time wherein POS470FC was chosen as bipolar plate material. To ensure good robustness of the metallic bipolar plate based DMFC stack, finite element method based simulations are conducted using a commercial ANSYS Fluent software. The stress buildup and deformation characteristics on bipolar plates and end plates are analyzed in details. The present DMFC stack exhibits the performance of 1,130 W at 32 V and 35.3 A, clearly demonstrating that it could successfully operate for UAVs requiring around 1,000 W of power.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2007년도 제28회 춘계학술대회논문집
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• pp.87-90
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• 2007

장기 체공 무인 항공기를 위한 연료 전지 동력 시스템을 개발하였다. 기존의 고압 수소 저장 방식의 문제점을 해결하기 위해 높은 에너지 밀도를 갖는 액상의 화학 수소화물을 연료로 사용하였다. 수소화물을 전환하여 수소를 발생하는 연료 공급 장치는 촉매 반응기, 펌프, 연료 카트리지, 분리기, 제어기로 구성되어 있으며, 전력을 발생하기 위한 연료전지 스택과 함께 연료 전지 동력 시스템을 무인 항공기에 탑재하였다. 연료 전지 동력 시스템을 무인 항공기에 적용하기 위한 성능 검증을 수행하였다.

• 한국수소및신에너지학회논문집
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• 제22권6호
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• pp.819-826
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• 2011

The proton exchange membrane fuel cell (PEMFC) is regarded as the most promising alternative power sources for unmanned aerial vehicle (UAV) due to its high energy density and silent operation. Since there are many load changes during UAV flight, thermal management is one of the important factor for the performance of PEMFC. In order to reduce the UAV weight for the stable operation of UAV, thermal management system (TMS) studied in this work does not use the fan but use the air flowing into UAV by UAV flight. In order to develop the passive type heat exchanger (HEX) for 1kW PEMFC, four types of HEXs are fabricated and their cooling performances are compared. The parametric study on the cooling performance of HEXs has performed with the variation of operating parameters such as mass flow rates and inlet temperature of air and coolant. Type 4 has the best performance in every case. This study can be helpful to achieve the optimal design of HEX for PEMFC powered UAV.

• 한국수소및신에너지학회논문집
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• 제23권3호
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• pp.256-263
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• 2012

We studied the degradation phenomenon of Pt catalyst in PEMFC. We used the electron microscope analysis technique including the ultra-microtome pretreatment method, FEG-SEM and TEM analysis methods for analysis of Pt nanoparticles. The Pt catalyst degradation is observed not only in electrode site but also in membrane site. We investigated these various degradation phenomena. The cathode electrode layer thickness is reduced. The size of the catalyst is increased much larger than initial size in membrane site. The catalyst moved from electrode layer to the electrolyte membrane. The rounded shape of catalyst was changed to the polygon. As a result, we found that the catalyst degradation processes of migration and coarsening occurred by the followings mechanisms; (1) dissolution of Pt ; (2) diffusion of Pt ion ; (3) Pt ion chemical reduction in membrane; (4) Coarsening of Pt particles (Ostwald ripening) ; (5) polygon shape change of Pt by {111} plane growth.

• 한국수소및신에너지학회논문집
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• 제23권4호
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• pp.330-336
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• 2012

FCEV uses 250 ~ 450 V instead of using 12 V battery. High voltage vehicle can cause electric shock, fire and explosion accident. Therefore, it has potential factors that can cause hazard of safety for users. United states of America and Europe legislate regulations such as ECE R100, FMVSS 305 for regulating electrical safety during driving or after collision. The company manufacturing high voltage components must do advanced R&D about Method for improving and confirming the safety of high voltage. We develop the specific hardware components of high voltage wiring system for the power train system and power supply system of Hyundai Motors FCEV. This paper shows test method of insulative performance for securing the electrical safety of high voltage components such as power cable, connectors and buss-bar, and proposals the guide line value for human safety of FCEV according to the test result of our development components.

• 한국수소및신에너지학회논문집
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• 제29권5호
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• pp.497-502
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• 2018

In Korea, passenger car and van using LPG fuel including taxi constantly increased due to the high cost of fuel. Recently, the emission standard has continuously tightened in the world. In this investigation was conducted the greenhouse gas emission characteristics of LPG vehicles according to the displacement and weight. Exhaust emission characteristics of 13 test LPG vehicles from about 1.0 L to 3.0 L displacements were measured and analyzed by using chassis dynamometer and emission analyzer. It is revealed that the greenhouse gas emission was showed the increasing tendency as the displacement and curb weight increased. Also, greenhouse gas emission of SC03 driving cycle has highest value and that of HWFET driving cycle shows the lowest value.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제36회 춘계학술대회논문집
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• pp.175-178
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• 2011

본 논문에서는 자세제어용 추력기에 사용되는 단일액체추진제의 성능특성 및 활용현황을 조사한다. 과산화수소는 단일추진제로서 1960년대 중반까지 활발히 사용되었으나, 비추력 성능과 저장성이 탁월한 하이드라진으로 급속히 대체되었다. 하이드라진은 양호한 성능특성을 배경으로 인공위성, 행성간 탐사선, 우주발사체 등의 단일추진제로서 가장 많이 사용되고 있다.

• 한국가시화정보학회지
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• 제17권1호
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• pp.85-92
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• 2019

Numerical visualization is conducted to confirm the variation of flow characteristics and pressure drop by the shape of channels on the cathode flow path in hydrogen fuel cells for unmanned aerial vehicles(UAVs). Generally, a light-weight fan is commonly used rather than a heavy air compressor at UAVS. However, in case of blower fan, a large pressure drop in the flow path causes the blocking of the oxygen supply to the fuel cell. Therefore, the uniformity of flow inside the cathode has to be achieved by changing the shape of the cathode. The flow channel, the duct shape, and the diameter of the fan are changed to optimize the flow path. As a result, it is confirmed that the optimal flow path can decrease the velocity difference between the center and outer flow by 1.8%. However, It should be noted that the channel size can increase the pressure drop.

• 한국수소및신에너지학회논문집
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• 제32권4호
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• pp.271-276
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• 2021

Although the development of electric vehicles or electric commercial vehicles is underway in Korea, most companies are seeking to enter the global market because it is difficult to expand their business only in the domestic market. In addition, it is recognized that the country has difficulties in responding to regulations or related procedures when entering overseas markets, and due to such difficulties, it is not possible to gain opportunities to enter the market and gain the technical advantage. Therefore, it is necessary to support individual companies to overcome the difficulties of promoting and exporting products by establishing a pre-cycle support environment for technology development so that development parts can be installed in small electric commercial vehicles. Therefore, this study tried to understand the necessity and factors of small electric commercial vehicles for major ASEAN countries, and as a result, most of them raised the urgency and necessity of joint research.In addition, human resource development, government support, and technical support were suggested as the necessary factors for the study.