• Proceedings of the KSME Conference
• /
• 2002.08a
• /
• pp.843-846
• /
• 2002

Unlike ordinary train, the HST(High Speed Train) is operated at a very high speed, which may cause pressure transient problems when the HST is passing through a station. In the present study, the wind pressure caused by the passing HST was measured in the Cheonan HST station and compared with the numerical simulations. For the measurement, the HST was passing through the station at speeds of 240 km/h north bound and 150 km/h south bound. MEMS based differential pressure transducers are used to measure pressure variation at various locations in the station. It is shown from the results that measured data are in good agreement with CFD simulation with moving mesh technique for the train movement. With the present validation of CFD simulation, the CFD simulation may effectively aid the design of future HST station.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2006.05a
• /
• pp.982-987
• /
• 2006

In general, the braking system of high speed train has an important role for the safety of the train. To stop safely the train at its pre-decided position, it is necessary to combine property the various brakes. Generally high speed train has adopted a combined electrical and mechanical (friction) braking system. Electrical brakes are consist of rheostatic brake, regenerative brake and eddy current brake and mechanical brakes are composed of disc brake, wheel disc brake and tread brake. In this paper, we introduce braking performance analysis and inspection though simulation and research to reduce braking distance.

• Proceedings of the KSR Conference
• /
• 2003.10c
• /
• pp.275-280
• /
• 2003

The Korean high speed train is designed to run at very high speed such as 350km/h. At this time, ballast in roadbed is dispersed by high speed air flow and this hits the substructure of the train. It becomes the factor of damaging the train. To investigate the main factor and possibility of ballast dispersion, the substructure flow is measured by Kiel-Probe Array System at G7 train experiment. And the wind tunnel experiment is performed with ballast in our research. Also CFD analysis is performed by assuming that the flow field is 2D and using simple shaped cross-tie and flat substructure of the train. By comparing the experimental results and CFD analysis, the accuracy of the analysis is checked. They will become the basic research data for the analysis and optimization of train substructure to prevent the ballast dispersion.

• Journal of the Korean Society for Precision Engineering
• /
• v.29 no.6
• /
• pp.593-599
• /
• 2012

To analyze the effect of the track structure on the running performance of the railway vehicle, we studied on the vibration and ride characteristics of the high speed train. As results, vibration and ride level of high speed train on the concrete bed track is more reduced than on the ballast bed track. Peak-peak value of carbody vibration on the concrete bed track at 300km/h is half of the peak-peak value of carbody vibration on the ballast bed track. Ride level on the concrete bed track at 300km/h is same level as that on the ballast bed track at 250km/h. Thus, Vibration and ride performance of the high speed train on the concrete bed track is greatly improved compared with that on the ballast bed track.

• Proceedings of the KSR Conference
• /
• 2003.05a
• /
• pp.533-541
• /
• 2003

This paper shows the results of train system engineering technology and exterior and interior design of a prototype test train(HSR 350X) which was developed in R&D project titled 'Development of High Speed Railway Technology'. The prototype test train, which has two power cars, two motorized trailers and three trailers, is now being tested on high speed line.

• Proceedings of the KSR Conference
• /
• 2002.10a
• /
• pp.137-142
• /
• 2002

This paper shows the results of exterior and interior design of a prototype test train(HSR 350X) which was developed in R＆D project titled "Development of High Speed Railway Technology". The prototype test train, which has two power cars, two motorized trailers and three trailers, is now being tested on high speed line. The improved conceptual design work of a new commercial train and next generation′s train is also peformed for future needs.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.28 no.6
• /
• pp.734-739
• /
• 2004

The aerodynamic effect on platform during the train passage, the results of field test on the high-speed railway platform are discussed and the whole test results and conclusions are synthesized. The field test for the high-speed railway have been conducted on the Osong temporary platform in the newly constructed Seoul-Busan high-speed line and total 12 measurements have been conducted for G7 train and KTX train. The results shows that the high-speed trains have similar aerodynamic characteristics and have far better characteristics referring to the conventional trains such as Saemaul and Mugungwha trains. To discuss the actual aerodynamic effects on the platform at its own operational speed, Beaufort wind scale have been introduced and the criteria for the safety on railway platform has also been discussed.

• Proceedings of the KSR Conference
• /
• 2005.05a
• /
• pp.356-361
• /
• 2005

The Korean High Speed Train(KHST) had been developed and evaluating on the Kyoung-Bu High Speed Line by through 'G7-R&D project'. In order to evaluate the function and characteristics of high speed train system, various experimental conditions have been considered and conducted. In this paper, current collection characteristics of KHST between pantograph and catenary system and dynamic behaviors are measured and analysed over 300 to 350km/h in running speed of KHST. A measuring system which was developed and installed on the Korean High Speed Train for the performance and mechanical characteristics of the KHST pantograph is used for this trial running test and we proofed that KHST has a remarkable and stable current collection characteristics as it had been designed.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.14 no.10
• /
• pp.999-1006
• /
• 2004

Recently, the ride comfort problem becomes increasingly important because of today's needs for train speedup. The railway has the track irregularities which cause vibrations, such as rail joints, turnout, level crossing, transition corves and super-elevation ramps, and variations in the track level(z-axis) and the gauge(y-axis). In Korea, the service run of the high speed train has been made since the 1st of April, 2004. The commercial high-speed trains must be run on the compound lines which are composed of high-speed line and conventional line. The high speed lines in both Kyoungbu line and Honam line have 57.5％ and 33.8％, respectively In this Paper, the ride comfort has been reviewed by the various experimental methods when the high-speed trains are operated on both Kyoungbu line and Honam line. The results show that the high-speed train has no problems from the viewpoint of the comfort ride during the operation on the high speed line and conventional line.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.67 no.1
• /
• pp.131-136
• /
• 2018

Reliable velocity estimation technology for trains is one of technologies used to operate trains safely and effectively. Various sensors such as tachometers, doppler radars, and global positioning systems are used to estimate velocity of a train. Tachometer is widely used to estimate velocity of a trains due to its simplicity, small volume, cost-effectiveness, continuously measurement at high speed, and robustness against noise. Accuracy in the velocity calculation using a tachometer depends on quantization error, measurement error of wheel radius or diameter, and tachometer's imperfection from manufacturing or installation process. In this paper, we present an accurate velocity estimation method using a low-resolution tachometer, which is commonly installed on a high-speed train. Baseline estimation method is proposed to accurately calculate the velocity of the high-speed train from tachometer's pulses. HEMU-430x test train is used for the experiment and verification of the proposed method. Experimental results with several routes show that the proposed method is more accurate than a conventional method.