• 전력전자학회논문지
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• 제14권6호
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• pp.481-487
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• 2009

슈퍼커패시터를 이용하여 철도 차량의 가 감속 시에 발생하는 DC 가선전압의 변동을 안정화하는 방법을 제안하였다. 이를 위해서 슈퍼커패시터를 서로 다른 3개의 시정수를 가지는 전압가변 정전용량을 가지는 RC회로로 가정하고 실험적인 방법으로 파라미터 값을 결정하여 전기적인 모델링을 수행하였다. 슈퍼커패시터를 이용한 에너지 저장장치를 구성하여 시뮬레이션 및 실험을 통하여 제안된 모델을 검증하고 제어기를 설계하였다. 그리고, 경산 시험선에서 실증시험을 수행하고 경제성을 평가하였다.

• 한국철도학회논문집
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• 제17권5호
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• pp.381-389
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• 2014

본 연구에서는 카셰어링 이용특성자료 및 GIS를 활용하여 입지특성과 관련된 도시 및 지역적 사회경제에 대한 DB를 구축하였으며, 주성분분석을 통해 잠재변수를 도출하였고 요인점수를 활용한 다중회귀분석을 통해 영향변수의 의미를 살펴보았다. 업무중심지역 및 역세권지역, 대학교인근지역에서의 활용도가 높았고, 특히, 전기차에 대한 관심도가 카셰어링 이용도에 영향을 미치는 것으로 파악되었다. 한편, 금융기관이 집중된 지역 및 영업용(택시)차량 배치가 많은 지역에서는 이용이 제한되는 것으로 나타났다. 본 연구의 분석결과는 향후의 카셰어링의 활성화와 공유가치에 대한 시민의 이해도 향상과 소유에서 공유로의 발상전환에 기여할 것으로 판단된다.

• 한국화재소방학회논문지
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• 제20권2호
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• pp.21-30
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• 2006

2003년 대구지하철 방화사고 이후 서울의 도시철도 7호선 방화를 비롯해 해외에서도 이와 유사한 모방 범죄가 발생하고 있다. 지하철의 방화사고는 대부분 유류나 가스 등을 이용한 방화유형이 대표적으로 발화 후 수분 내에 차량 내부가 전소될 수 있어 궁극적으로 지하철 전노선을 마비시키는 결과를 초래할 수 있다. 따라서 화재발생과 확산을 단계적으로 차단하거나 화재로부터 신속히 격리할 수 있는 효과적 초기 대응의 대안을 제시함으로서 대형 재난을 피할 수 있다. 본 연구에서는 국내외 지하철 방화 사고의 진행과정을 분석하여 대응 단계별로 방화 상태의 피해확인 및 인지 여부, 초기진화 여건 판단, 대응 조직의 상황전파 및 피난유도과정을 비상상황 등급별로 시나리오상에 전개했다.

• 대한기계학회논문집A
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• 제37권6호
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• pp.723-730
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• 2013

기존선에서의 속도향상을 저해하는 요인은 매우 다양하지만, 그 중 분기기 통과속도 제한규정을 가장 대표적 사례로 손꼽히고 있다. 현재, 기존선 분기기의 직선측 최고 통과속도는 일반 선로의 차량 최고 주행속도에 비하여 낮은 속도로 제한되어 운행하고 있으며 분기기내에서 주행속도를 제한하는 것은 분기기 통과 시 철도차량의 주행안전성을 확보하는데 목적을 두고 있다. 본 연구에서는 대구도시철도공사의 분기기 가드레일에 대한 형상 변경사례를 기반으로 하여, 분기기에서의 차륜/레일 형상에 따른 기하학적 관계식을 이론적으로 검토하였으며, 개발한 VI-Rail 분기기 해석기법을 통하여 F10/F12 분기기에서의 가드레일 길이 변화에 따른 주행안전성 해석을 수행하여 그에 따른 영향을 살펴보았다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.374-377
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• 2005

Automobile is in charge of most transportation system in modern urban city. However, in fact, cause of problem of road state, environment, and the other reasons, urban transit system is using as Mass Transit nowadays. Nevertheless Urban transit system is considering many kind of safety fact of that system which is increasing continuously nowadays, it occurs various train accident. This paper describes 3D Dimensional Measurement(EDM testing) and tensile testing results of carbody structure for crashed EMU(Electric Multiple Units). Tensile tests were performed on two different types of specimens in order to evaluate the strength changes before and after damages, obtained from plastic deformed area and nondeformed region of the crashed EMU. And Structural analysis of EMU was performed for the criteria of safety assessment. Structural analysis using commercial I-DEAS software provided important information on the stress distribution and load transfer mechanisms as well as the amount of damages during rolling stock crash. The testing results have been used to provide the critical information for the criteria of safety diagnosis.

• 전기학회논문지
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• 제63권3호
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• pp.431-436
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• 2014

In this paper, temperature change properties on the 210kW-class Interior Permanent Magnet Synchronous Motor (IPMSM) are performed with the cooling performance of a water cooling device through the thermal characteristic analysis of the IPMSM considering a real driving pattern of urban railway vehicles. First, the thermal analysis modeling of 210kW-class IPMSM, which is an alternative to the conventional induction motor, and its water cooling device is conducted. Next, the thermal characteristic analysis of the IPMSM considering a real driving pattern of urban railway vehicles is performed using 2-Dimensional FEM tool. Finally, the calculated characteristic results are analyzed. Consequently, it is confirmed that the internal temperature of the 210kW-class IPMSM may be lowered to about 42~52% by maintaining the coolant flow rate of the water cooling device (Cross sectional shape of the pipe has 220mm width and 10mm height) for 0.2kg/s level.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1051-1055
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• 2003

Aluminum carbody for rolling stocks is light and perfectly recycled, but includes severe defects which are very dangerous to fatigue strength. Structural integrity assessment for the carbody by static load test has been performed up to date. In this study, to evaluate fatigue strength of the aluminum carbody of urban transit unit. a testing method to simulate dynamic loading condition was proposed and the fatigue strength of the carbody was evaluated. The dynamic load test results showed that the alternating stress ranges were different from the estimated ranges based on the static test results. Excessive stress ranges at the center are thought to come from the flexible motion of the carbody. published fatigue test data for aluminum components, but variation of alternating acceleration along the length due to flexibility of carbody yielded unexpected results. Because fatigue strength based on the static test results may be overestimated at the center, modification of testing method is necessary.

• 한국안전학회지
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• 제27권3호
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• pp.117-124
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• 2012

There have been recently introduced new types of urban metro vehicles called LRT (Light Rail Transit) running on elevated guideway such as Uijeongbu VAL(which stands for V$\acute{e}$hicule Automatique L$\acute{e}$ger: Automatic Light Rail Vehicle) system, Yong-In LIM(Linear Induction Motor) system, Incheon international airport MAGLEV(Magnetic Levitated Vehicle) system and Daegu monorail system. Most of accidents by the vehicles are bound to happen on elevated guideway. Therefore, it is of vital importance to analyze hazards related to vehicles running on elevated guideway and study emergency evacuation scenarios applicable in case of accidents on elevated guideway so as to secure the safety of the new types of urban metro vehicles. In this study, FTA(Fault Tree Analysis) model was developed to identify all possible hazards, and all possible evacuation scenarios were studied. It was also confirmed that each hazard can be corresponded to one or more evacuation scenarios. This result shows that passengers can be evacuated according to one of the scenarios identified in this study in case of an accident of "Train Stranded on Elevated Guideway".

• 전기학회논문지P
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• 제59권3호
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• pp.268-274
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• 2010

Urban rail transit brings the benefits of various aspects of society. With the advent of fast and large trains, however, risk and scale of accidents have increased. Despite the fact that there is various safety features built into the modern metros, train faults happen from time to time. Especially, as urban railway vehicles in Korea have become deterioration rapidly, more advanced diagnosis methods are required to prevent various accidents. In this paper, we present diagnosis method for electrical wires to guarantee secure driving and authenticity more accurately in urban railway vehicles. Although there are kinds of conventional methods based on insulation resistance measurement and withstand test, it is extremely difficult to effectively diagnose obsolete equipments such as electrical wires and cables not new ones. This study is focused on development of diagnosis method and establishment of evaluation standard for electrical wires in urban railway vehicles.

• 한국기계가공학회지
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• 제15권2호
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• pp.57-65
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• 2016

The suspension system of a subway vehicle is composed of $1^{st}$ and $2^{nd}$ springs. The suspension system is the most important parameter in determining the vibration ride comfort. If the $1^{st}$ suspension spring is designed as a spring with strong stiffness to improve the running stability at high speed, it causes vehicle vibrations. In this paper, by testing and analyzing changes of the characteristics of Chevron springs, which have been the primary suspension springs used for about 20 years, we study how changing the characteristics affects vehicle acceleration and ride comfort. The lateral and longitudinal vibrational ride comfort index levels were lower than the vertical ones. Therefore, as increasing the stiffness of Chevron springs has the greatest effect on the vertical vibrational ride comfort index level, a countermeasure for vertical vibration reduction is needed when the stiffness increases owing to aging. Finally, maintenance guidelines, including the replacement time for the Chevron rubber, were proposed based on these findings.