• Journal of the Korean Society for Railway
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• v.6 no.1
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• pp.41-48
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• 2003

Most of people spends their times in indoor about 85% of a day. Thus, indoor is more serious than outdoor concerned with the health. We discussed comfortableness in a railroad electric rolling stock, and focused on temperature and humidity. Electric rolling stock is one of major public transportation system because of an increasing in population and heavy traffic problems. The passengers are under the influence of indoor air quality such as air temperature, relative humidity and air velocity. Ventilation system in electric rolling stock should be designed for the health and comfort. One of the main aims is to create an acceptable thermal environment without draught problem. The draught sensation increases when the air temperature decreases and the air velocity increases. Airflow in electric rolling stork is turbulent. Temperature and humidity gradients in electric rolling stock have been studied. And, the difference between mean temperature and rotative humidity measured at 0.7, 0.9, 1.2, 1.7m above the floor. It has been found that temperature and relative humidity with large fluctuations caused more draught complaints.

• Proceedings of the KIEE Conference
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• 1997.07a
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• pp.373-375
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• 1997

In this paper, we present IGBT VVVF inverters as a 1C1M propulsion system for electric car. These inverters are composed of high power IGBT's and controlled by compact control units. The control unit performs full digital control by using 32bit DSP and microcontroller. By using CAN-bus, high speed network is constructed within four control units. The stack is simplified and optimized by using plate bus and IGBT driver units of hybrid-type.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.54 no.4
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• pp.192-197
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• 2005

This paper presents a development of the auxiliary power supply simulator for a electric rolling stock. An auxiliary power supplies are required for operating air conditioning units, ventilation fans, lighting and battery charging. Traditionally this function has been fulfilled by Motor-Alternator sets. In recent years, high performance of semiconductor and micro processor, availability and price have made three phase voltage source inverters as an attractive alternative to MA Sets. From the baseline model of the SIV(Static InVerter) for electric rolling stock, we designed the scale down model of the auxiliary power supply simulator consisting of an IGBT three phase voltage source inverter. The auxiliary power supply simulator can be used educatory purpose for training efficiently about operating principles of SIV.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1782-1793
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• 2008

Republic of korea has begun operating high speed train service according as KTX service operation starts in 2004. Also, EMU whose maximum speed is over 150 kph will be starting to service with electrification and improvement of existing railroad. Moreover, metropolitan electric railways have begun an express service to increase scheduled speed. Therefore, running resistance of rolling stock becomes more important factor effects on the performance. Running resistance of rolling stock is the factor which is necessary for the performance or operation plan of rolling stock, and it's related to rolling friction, slip friction, drag force, gradient, acceleration, curvature, tunnel condition and so on. It is possible to be calculated by CFD (Computational Fluid Dynamics). However it is predicted by experimental equation from running resistance test because of the complex calculation and manifold variables. In this paper, studies about running resistance of rolling stock is introduced, and each term of experimental equation is studied through theoretical approximation. Also, running resistance of rolling stock is estimated by the result of running resistance test, and effects being related to friction, drag force, gradient is examined.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.2094-2100
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• 2008

The indoor PMV(Predicted Mean Vote) in rolling stock is very important for the enhancement of the amenity and health of passengers. Many researchers have studied it not for train but for building. Thermal comfort in Rolling Stock is function of temperature, relative humidity, air current, radiation temperature, etc. So, in this study, we have performed thermal environment in rolling stock(Electric motor car, Saemaeul, Mugunghwa train), and verified the relation between the PMV from Nov.2007 and Feb.2008. As a result, the average PMV value for each trains are 0.2, -0.3 Electric motor car, 0.5, 0.1, 0.1, 1.1 for Mugunghwa, 0.3, 0.5 for Saemaeul.

• Proceedings of the KSR Conference
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• 2003.10c
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• pp.91-97
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• 2003

In many countries such as Japan, France and so on, the number of double-deck trains has been dramatically increased for the purpose of public traffic. Several researchers have performed feasiblilty studies related to the operations of double deck rolling stock vehicles in Korea since 2001. In recent years, rolling stock vehicles are required to have light weight to save energy consumption and maintenance costs. For these reasons, the standard EMU vehicle developed by KRRI and Kwan-Ju EMU(Electric Multi Unit) are made of aluminum extruded panels. The concept model of a double-deck rolling stock vehicle investigated in this study is also designed to use AEP(Aluminum Extruded Panel). In this paper, the methods related to the structural strength improvements of the car body are proposed through careful modifications of thicknesses and shapes of AEP.

• Journal of the Korean Society for Railway
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• v.16 no.3
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• pp.183-188
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• 2013

The purpose of maintaining rolling stock is to perform train service without failure during operation. It is not possible to prevent failure, however, by using periodic preventive maintenance methods, because new rolling stock is made from many electric components and requires the application of IT skills. RAMS (Reliability, Availability, Maintainability, Safety) methods have consequently been applied to new manufactured rolling stock in KORAIL since implementation of the KTX. With this approach it is possible to verify the reliability at the operating stage, and RCM (Reliability Centered Maintenance) methods for maintenance have been applied to manufactured rolling stock since the beginning of KTX service. A RCRM (Reliability Centered Rolling-stocks Maintenance) system suitable for the characteristics of rolling stock and operational factors is introduced in this paper.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.393-397
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• 2005

Since the braking system of rolling stock is directly linked to it's safety, ensuring reliability of braking system and evaluation of performance of it are very important. To develope the performance of braking system, it is required advanced technology and gradually various factors in the field test result. This study is designed to analyze the air pressure control about braking force in rolling stock, also, by comparing braking force of high speed railway with that of high speed train. This paper suggests to establish a method of computation of braking force form the air pressure control. And The high speed train researches into patterns of braking system such as the train of speed up and introduction of electric and pneumatic braking system.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.889-894
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• 2005

This paper describes the development of the auxiliary power supply simulator for electric rolling stock. Auxiliary power supplies are required for operating air conditioning units, ventilation fans, lighting and battery charging. From the baseline model of the SIV(Static InVerter) for electric rolling stock, we designed the scale down model of the auxiliary power supply simulator consisting of IGBT voltage source inverter. Auxiliary power supply simulator can be used educatory purpose to teach efficiently about operating principles of SIV

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.610-615
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• 2003

Electric rolling stock is one of major public transportation because of an increase in population and heavy traffic problems. The passengers under the influenced of indoor air quality such as air temperature, relative humidity and air velocity. Ventilation system on passenger cars should be designed for the health and comfort of the passengers. One of the main aim is to create an acceptable thermal environment without draught problems. The draught sensation increases when the air temperature decreases and the air velocity increases. Airflow in passenger cars is turbulent. Lateral temperature and humidity gradients in the electric rolling stock have been studied. And, the difference in the mean temperature and relative humidity measured at 0.7, 0.9, 1.2, 1.7 m above from the floor.