• Proceedings of the KIEE Conference
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• 대한전기학회 1995년도 하계학술대회 논문집 A
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• pp.274-277
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• 1995

Recent environmental pollutions have intensified the need to develop zero emission vehicles. The most effect method of such solutions is EV. EV is high energy efficiency, easy to maintain, repair and is possible to make high performance control. However, because energy density of batteries is constrained and the distance covered one charge is short range. Also because EV has disadvantage of poor accelation ability, development of high performance battery is required for large scale use of EV. EV charger analogous to gas apparatus must also be developed immediately. Charger is discriminate between on-vehicle type and off-vehicle type. As off-vehicle type is able to charge fast and safe, inductive charging is considered. This paper aims to develope off-vehicle inductive charging system. Therefore, it achieved power factor correction converter, high frequency DC/AC inverter control algorithm development which gives proof validity through simulation and formulated the basic concept of high frequency transformer design for inductive charging.

• Transactions of the Korean Society of Automotive Engineers
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• 제24권3호
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• pp.265-272
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• 2016

The objective of vehicle aerodynamic design is on the fuel economy, reduction of the harmful emission, minimizing the vibration and noise and the driving stability of the vehicle. Especially for a sedan, the driving stability of the vehicle is the main concern of the aerodynamic design of the vehicle indeed. In this theoretical study, an evaluation algorithm of aerodynamic driving stability of a vehicle was made to estimate the dynamic stability of a vehicle at the given driving condition on a road. For the stability evaluation of a driving vehicle, CFD simulation was conducted to have the rolling, pitching and yawing moments of a model vehicle and compared the values of the moments to the resistance moments. From the case study, it is found that a model sedan running at 100 km/h in speed on a straight level road is stable under the side wind with 45 m/s in speed. But the different results may be obtained on the buses and trucks because those vehicles have the wide side area. From the case study of the model vehicle moving on 100 km/h speed with 15 m/s side wind is evaluated using the numerical algorithm drawn from the study, the value of yawing moment is $608.6N{\cdot}m$, rolling moment $-641N{\cdot}m$ and pitching moment $3.9N{\cdot}m$. These values are smaller than each value of rotational resistance moment the model vehicle has, and therefore, the model vehicle's driving stability is guaranteed when driving 100 km/h with 15 m/s side wind.

• Journal of Power System Engineering
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• 제21권4호
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• pp.57-61
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• 2017

The vehicle label fuel economy is used as an energy management indicator nationwide. It induces technology development of automobile manufacturers and plays a role of providing information when purchasing a consumer vehicle. However, consumers who purchase a new vehicle continued to complain that the label fuel economy is different from the mandatory fuel economy rate. The domestic fuel economy measurement method is the same as the North American measurement method. The results of the two test modes (urban (FTP-75 mode), highway (HWFET mode)) are calculated in five test modes reflecting various environmental conditions and driving patterns 5-cycle correction formula is used which is equivalent to the fuel efficiency value. In this study, to solve the consumers' curiosity about the fuel economy of new vehicle, we use domestic fuel economy measurement method to measure the new car condition within 150 km of driving distance and the cumulative driving distance condition of domestic label fuel economy test vehicle. A comparative evaluation of fuel economy was carried out for a durability vehicle of $6,500{\pm}1,000km$. A result, mean value of the fuel economy of the four gasoline vehicles increased by 2.7 % in the city center mode and by 2.5 % in the highway mode in the durable vehicle compared new vehicle. And in the case of the diesel vehicle it increased by 2.5 % and 3.9 % respectively. The harmful exhaust gas emitted from the vehicle also resulted in more emissions of both gasoline and diesel vehicles in new vehicles. It is considered that the increase of the frictional force of the vehicle driving system and the lubricating oil system would have an effect on the reduction of the fuel economy of the new vehicle, and it was found that the fuel economy and the exhaust gas were improved by proper cumulative distance (domesticate) to the new vehicle.

• Journal of Environmental Policy
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• 제12권4호
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• pp.45-69
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• 2013

This study estimates baseline greenhouse gas emissions from transport sector when a new town is developed. It has adopted a general greenhouse gas estimation model developed by Schipper, celine, Roger(2000) for the estimation, and showed how various transport related statistics can be utilized in detail. Particularly, it has produced unit greenhouse gas emission factor per vehicle types, vehicle-km, and trip-km. To evaluate effects of greenhouse gas reduction policies, it has calculated how much emissions will be reduced from bicycle promotion. It has turned out that about 369 thousand tons of carbon dioxide will be emitted from transport sector once the 1st Geomdan New Town is developed in Incheon metropolitan city. If the policy of bicycle promotion can attract people to use bicycle as much as 5% of total trips, then it can reduce about 1,869 tons of carbon dioxide.

• Journal of Korean Society for Atmospheric Environment
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• 제29권4호
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• pp.477-485
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• 2013

The major source of harmful air pollutants in Korea have been shifted as economy grows. Particulate matter(PM) and Sulfur dioxide ($SO_2$) emitted from industries and coal-fired domestic sectors were important pollutants in 1970's and later industrializing period of Korea. Then the characteristic of pollution was changed into so-called "developed country type pollution". Vehicles have been responsible for significant amount of Nitric oxide ($NO_x$) pollution and consequent Ozone formation in urban area since 1990's. Variety of control measures have been introduced to deal with the vehicle emissions in Seoul Metropolitan Area (SMA). Emission control technologies have successfully reduced pollutants from vehicles. Three-way catalyst for vehicles fueled by gasoline and liquefied petroleum gas (LPG), for example, has achieved large amount of pollutants. Compressed natural gas (CNG) urban bus have penetrated existing diesel bus market and reduces PM and $NO_x$ emissions in many Korean cities. However, diesel vehicles are still reaming as a critical emission source of urban area. Diesel vehicles gain more popularity than ever because of their better fuel efficiency and driving power. Unfortunately, it is widely known that the pollutant emissions of diesel vehicles are much larger than those of gasoline and LPG vehicles. In this note, we briefly introduce the trends of emission control strategies which are accomplished by automotive industries for about last ten years. Emission regulation, cleaner fuel, diesel particulate filter (DPF) and other measures are discussed from technical as well as legislative perspectives.

• Journal of Korean Society of Transportation
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• 제27권4호
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• pp.183-193
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• 2009

Air pollution due to vehicle exhaust gas is considered to be a main contributor to the issues of transportation & environment. Furthermore it is raising concern over life quality and public health and is also perceived as a global issue. This research aims at providing helping hands for both central and local governments to set up and promote efficient atmospheric quality improvement policies, with the help of the travel demand forecasting model and GIS. More specifically, it tries to produce the overall emission level with time and space-based high resolution framework. This research, based on bottom-up approach reflecting vehicular traffic characteristics, suggested an improved approach to estimating emission level, by using a traffic model with a total of vehicular mileage revised by surveyed value and atmosphere model. Summing up, using the method proposed, the improvement of the reliability of the emissions inventory from the mobile pollutions sources is expected by the proposed integrated paradigm of transportation and atmosphere modeling approach as a new alternative.

• Journal of ILASS-Korea
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• 제23권4호
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• pp.175-184
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• 2018

Emission characteristics of regulated (NOx, PM, CO, NMHC) and unregulated (VOCs, aldehydes, PAHs) air pollutants were investigated for diesel heavy duty buses equipped with different after-treatment systems (DPF+EGR and SCR) under urban driving cycle. The combustion temperature and the working temperature of SCR catalysts were important to make impact on NOx emissions, whereas PM emissions were low. The alkane groups dominated NMVOCs emissions, making 42.6~59.4% of sum of the NMVOCs emissions. Especially, alkane emissions of DPF+EGR-equipped vehicle included DOC had 14.9~15.5% higher than those of SCR-equipped vehicle due to low efficiency of oxidation catalyst. In the case of individual NMVOCs, n-nonane and propylene emissions highly occupied for DPF+EGR and SCR, respectively. Formaldehyde emissions among aldehydes were the highest and PAHs emissions were hardly detected except naphthalene and phenanthrene. The NMHC speciation has been shown to be the highest of the formaldehyde ranged 20.8~21.5%. The results of this study will be contributed to establish Korean HAPs emission inventory for automobile source.

• Journal of Hydrogen and New Energy
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• 제29권6호
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• pp.654-660
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• 2018

The dependence on global fossil fuels has been gradually reducing all over the world. Some countries which recognized the important of environmental values were joining to carry out international GHG goals. Our country has also participated with high targets (37% reduction compared to BAU 2030 years). So we need to supply materials of lower GHG value such as a bio-diesel. Bio-alcohol is one of the similar bio-fuels that can be reducing GHG. A lot of countries had tried to commercialize through various R&D for bio-alcohol. In this study, we analyzed the fuel characteristics of bio-alcohol fuel produced by domestic technology. And we evaluated a possibility to use as vehicle fuel through mixing of bio-alcohol and gasoline. The mixed fuels were satisfied with 2.3 wt% of oxygen content that is standard of the petroleum and petroleum alternative fuel business Act. We tried to evaluate a emission characteristic of vehicle by mixed fuel. In accordance with the results we tried to find a correlation between fuel and emission.

• Transactions of the Korean Society of Automotive Engineers
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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.

• Journal of Korean Society for Atmospheric Environment
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• 제28권5호
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• pp.518-526
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• 2012

The objective of this research was to develop fugitive emission models of HFC-134a (Hydrofluorocarbon-134a) at the operation and disposal stages of passenger cars. It is essential to estimate the emission of HFC-134a from mobile air conditioner (MAC) due to its high Global Warming Potential (GWP) and extensive use as a refrigerant in MAC. The first-order emission model was introduced and the emission rate constant was assumed to be unvaried with time. A commercial recovery station of refrigerants was used to recover the HFC-134a from the MAC. Average emission rate constant and annual emission rate during the operation period of vehicle are estimated to be $0.0538{\pm}0.0092$ (n=21) $yr^{-1}$ and $5.2{\pm}0.6%$, respectively within a confidence interval of 95%. According to the model results, about 50% of HFC-134a would be emitted from the MAC during the 10 years operation of passenger cars. On the other hand, average remaining portion of HFC-134a in the MACs of scrap cars is $58.2{\pm}4.8%$ (n=50) within a confidence interval of 95%, suggesting that over 40% of the initially charged amount could be released fugitively after disposal provided that the HFC-134a would not be properly treated or recycled.