• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.503-509
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• 2004

With modem computational fluid dynamics method (CFD), air-charging models of the air brake pipe system and auxiliary reservoir are built. Compared with one-dimension model, no empirical formula is introduced to solve branch pipe fields for two-dimension model. A modified operator-splitting method is presented to solve the coupled equations of pressure and velocity, and numerical simulation shows that it is very stable. Compare the numerical results with empirical data of heavy haul trains in home and abroad so as to prove the correctness of the theory and algorithm presented. This paper gives theoretic reference to the experiments of braking effects of heavy haul trains, and forms a basis for development of complete freight train air brake system simulation.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제48권11호
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• pp.611-616
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• 1999

The introduction of the eddy current braking(ECB) system in HSRT(high speed railway train) is known to be advantageous, in that the system is independent on wheel-rail adhesion coefficient which is greatly affected by weather condition. It also minimize the maintenance of the brake system and does not require any additional electric energy because it is powered form the regenerated power at the time of the braking. In this study, the braking and attraction forces of the ECB are simulated by 2-D FEM and are experimentally verified on a down-scaled prototype. A control algorithm of the ECB is proposed to generate constant braking torque using linear variation of the reference current according to speed. Experimental results shows that the constant torque is generated over all operating speed region by developed control algorithm.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2001년도 추계학술대회 논문집
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• pp.267-272
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• 2001

A FEM-based analytical approach was used to evaluate the static strength and the fatigue strength of a KHST bogie including eddy current brake system. Calculation was carried out in the fields of linearity and small deformation. The yield strengths were used as criteria for evaluating the static strength and the fatigue limits were used as criteria for evaluating the fatigue strength. The analysis results show that there is not any location that exceeds the allowable criteria.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.372-374
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• 2001

An automatic operation of train is executed by an automatic train operation(ATO) system. The main function of ATO system is to control train speed as well as train brake system. So that train can stop at its programed position on platform and run with passenger comfort. In this paper, the gain scheduled control is designed for speed control considering the disturbances. The simulation is executed to verify the speed control performance and to compare its performance with the conventional PI and general Fuzzy control.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문초록집
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• pp.317.1-317
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• 2002

In this paper, static analysis of eddy current brake′s frame, which is one of key structural components of brake system for high speed train, was performed in order to evaluate the design by computer simulation. Calculation was carried out in general for the driving modes "braking" and "frame in upper position(brakes inactive)". Several yield stress load cases and fatigue load cases were analysed fur each of the driving modes. (omitted)

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1997년도 제26회 추계학술대회
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• pp.245-255
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• 1997

The thermal characteristics of a disk such as temperature distribution, thermal behaviours and thermal stress during a braking operation has been analyzed for a high-speed train using the finite element method. The maximum stress for a pad loaded against a disk was occurred at the trailing and leading edges of the disk pad at the underlayer-backplate interface. The FEM results indictate that the thermal characterisics of the spot type pad shows good performance compared with those of the flat type pad. Thus, the spot type pad in brake system may be recommended for the high-speed train system.

• 한국산학기술학회논문지
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• 제17권11호
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• pp.545-551
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• 2016

본 논문은 철도차량 안전의 핵심 요소인 제동성능을 확인하는 평가방법의 비교와 제동성능에 영향을 미치는 차륜과 레일의 마찰계수의 분포가 감속도에 미치는 영향을 분석하고 열차 편성에 따른 감속도의 분포를 예측하였다. 제동성능의 평가는 실제 운행중인 도시철도차량의 실차 시험을 통하여 제동시 제동거리와 제동시간을 측정해서 감속도를 산출하는 제동성능 평가방법과 UIC 544-1에 따른 제동중량비율을 이용한 평가 방법에 대하여 두 방법을 서로 비교하여 장단점을 살펴보았으며 각 방법의 호환성을 검토하였다. 차륜과 레일의 마찰계수 분포를 검토한 확률적 제동모델을 수립하고 제동성능에 가장 큰 영향을 미치는 차륜과 레일의 점착계수 분포가 열차의 편성에 미치는 영향을 분석하였다. 제동중량비율을 이용한 평가방법은 일정 초기 제동속도를 시험한 결과를 다양한 제동초기속도에서의 제동거리로 환산할 수 있어 열차 신호시스템의 설계나 신규 노선에서의 운전 패턴을 설계 검증할 수 있는 기초 자료로 활용이 가능할 것으로 보이며 편성에 따른 감속도의 확률적 분포 예측을 통하여 열차분리 결합등 가변 조성시 감속도의 분포를 예측함에 따라 보다 정밀한 열차신호 설계의 기초자료로 활용가능할 것으로 판단된다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.85-86
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• 2006

It presented the approach method for the station braking noise present condition and a braking noise reduction plan escape of the KTX train. The research which it sees the technical ground it will be able to accomplish the station braking noise reduction of the KTX vehicle with base the questing matter where the escape one thing is big there is a possibility of doing.

• 전기학회논문지
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• 제62권3호
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• pp.424-430
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• 2013

This paper presents a new design works for the braking chopper system which is included in the propulsion system of KTX high speed train. Due to the current fed type synchronous motors used in the propulsion system, some different behaviors are shown comparing to the voltage type other chopper systems. Specially this chopper system acts either braking controlling or regenerative power controlling system with a parallel resistive load in the propulsion system. In this paper, an improved simple high power IGBT brake chopper system has proposed which is able to be replaced with an existing complicated GTO chopper system. The analytical approaches to the parallel load type current chopper system and the propper snubber circuits calculation were explained in this paper to control new chopper system. In addition, the thermal resistance of the cooling system for power dissipation of IGBT modules was calculated also. Finally several PC simulations have been done to clarify its availability.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.611-618
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• 2000

The test facility of the 1/60-scale models for the train-tunnel interactions was recently developed to investigate the effects of entry portal shapes, hood shapes and air-shafts for reducing the micro-pressure waves radiating to the surroundings of the tunnel exits by KRRI in Korea. The launching system of train model was chosen as air-gun type. In present test rig, after train model is launched, the blast wave by the driver did not enter to inside of the tunnel model. The train model is guided on the one-wire system from air-gun driver to the brake parts of test facility end. Some cases of the experiments were compared with numerical simulations to prove the test facility.