• Journal of the Korean Society of Safety
• /
• v.32 no.3
• /
• pp.117-122
• /
• 2017

In this study, we studied the ride quality considering the deterioration effects of the three type couplers (single, double, and ring types) for EMUs. In order to know the impact occurred when an urban transit vehicle is under breaking, we tested the conditions of the service brake and the emergency brake. Normal coupler models without any slack showed similar dynamic performance results under all breaking conditions. But if the couplers become old, the initial pre-stresses are removed because of permanent compressive deformation in rubber. For three types of the old coupler models without the initial pre-stress, we evaluated dynamic performances of each type. As the results, the maximum and average acceleration levels of the double type and the ring type were similarly low in all conditions. But the accelerations of the single type coupler was high when compared to those of the double and ring types. In addition, Jerk value of the single type model associated with ride quality was high up to 15 times to the ring type in condition of the service braking in empty vehicle weight. Jerk value of the double type model was high up to 6 times to the ring type.

• Journal of Power Electronics
• /
• v.5 no.1
• /
• pp.45-54
• /
• 2005

This paper presents an application of SR drives for LSEV's(Low Speed Electric Vehicles) which are used for golf and leisure. Two types of 5[HP] SRM's and its drive system are designed and tested. In order to be energy saving and have effective braking during deceleration, a multi-level inverter is proposed. For the precise switching angle control, a new type of analog encoder is proposed. A current control is adopted for soft starting and an angle control is adopted at high speed to increase efficiency. Drive characteristics and performance are shown with test results.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.2594-2599
• /
• 2011

In Korea, the HEMU-400X(High-speed Electric Multiple Unit-400km/h eXpress) has been developed since 2007 and will be operated over 400km/h in 2013. It is necessary to prepare test-bed section in Honam high-speed railroad to take the maxim running speed test for the HEMU-400X developed. In order to determine proper test-bed sections for the maximum speed of 400km/h, TPS(Train Performance Simulation) program with the data of train model, running resistance, traction power and braking capacity was used to analyze the train performances such as locations, speeds and power consumptions by times. In this study, the specifications of the HEMU-400X project and the route conditions of the Honam high-speed railroad under construction were utilized for the TPS program to determine the optimal test-bed sections for the maximum speed of 400km/h.

• Proceedings of the KIEE Conference
• /
• 2008.10b
• /
• pp.466-467
• /
• 2008

There are many new technologies for EMU to secure the facilities' safety/validity and maintenance/economical efficiency and technologic competitiveness. For example, now the EMU is using the blending brake technology with electric brake and pneumatic brake and carrying the various performances such as jerk limitation, variable load and blending brake to stop the motor car safely and efficiently. The blending brake takes important parts in braking the cars and It is used in many fields of urban transit. There were many limitations to carry the performances and certificate whether the performances are acceptable in the system or not, because at that time they didn't take the whole prelieminarly inspection. Now we start applying such new methods, taking the whole inspection prior to the installation by analyzing systems requirements and introducing various system engineering design tools. In this paper, we suggest how to reduce the errors by prelieminarly inspection for the brake facilities using the tools and inspect the needs to analyze the brake facilities' performances.

• Proceedings of the KIPE Conference
• /
• 2011.07a
• /
• pp.34-35
• /
• 2011

특수 전기자동차 시스템에서는 기존 자동차 대비 차량 동력 특성, 제한된 공간, 시스템 효율 특성으로 인해 다중동력시스템을 주로 적용한다. 본 연구에서는 인버터를 통해 구동한 후 제동시 발생되는 전기에너지 즉, 회생에너지를 이용한 배터리 사용시간 증대의 효과를 가지는 특수 전기자동차의 회생제동 시스템의 구성, 개념도 및 제동원리에 대하여 서술하였다. 제안한 시스템의 검증을 위해 PSIM시뮬레이션을 수행하여 본 논문에서 제안한 회생제동 시스템이 특수 전기자동차에서 유용함을 확인하였다.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.1165_1166
• /
• 2009

In recent years, energy prices have soared, which of course have increased costs for railway operators. Simultaneously, the energy market has considerably changed that in most developed countries, it is deregulated, giving railway operators an opportunity to define new ways of using energy. Efficient operation of the railway system is considered as an essential way to energy saving while an efficient management of power level helps to lower the reference subscribed power, giving access to better energy rates. It is studied on the relation between time and force for the energy efficient driving of train in railway when the train is braking according to several slips.

• Proceedings of the KIEE Conference
• /
• 2001.07b
• /
• pp.889-891
• /
• 2001

The eddy current brake system is one of important application of eddy current. It is adequate to obtain safe braking force in high speed transportation system and electric vehicle etc. There is a variety of configurations and materials used in manufacturing of eddy current brakes. This paper proposes the eddy current brakes which uses permanent magnet. The dynamic characteristic has been analyzed to FEM and compared with measured data.

• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.2203-2206
• /
• 2005

A load flow and short circuit fault simulation of AC electrified railway distribution systems is presented with DIgSILENT PowerFactory software. Load flow of electrified railways distribution system with concerning multi train lines and dynamic characteristics of train load is studied for different time laps. The dynamic characteristics of train load in starting and braking conditions with different starting and stopping times and its moving positions makes the load flow complicated so there is a great need in studying the effects of electrified railways on load flow. Short circuit fault transients is also studied and simulated for both power system or traction distribution system and their effects on the operation of the train sets is investigated.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.51 no.7
• /
• pp.357-363
• /
• 2002

The target reliability values are defined for the train, signaling, rail track and electric power supply system of the LRT under development. The allocation of the reliability value is based on the failure rate and the failure type in the Korean subways. The reliability allocation in the train system is the made ore detail than others. The purpose of the allocation is to verify the reliability value of the results from each of the development stage, which could be the designing, manufacturing and purchasing work. The reliability of braking system, traction system, door system and other control system could be verified by establishing reliability models of these system. It could also enable us to estimate and analyse the reliability value and redo the work if necessary to achieve the shooting reliability value. A guide to the LRT reliability criteria is to be prepared after running test on the test track.

• Journal of the Korean Society for Railway
• /
• v.3 no.3
• /
• pp.170-176
• /
• 2000

Nowadays, the vehicle structure weight of urban transit system has been reduced in order to save energy and materials. However, this light weighted vehicle structure is very important to verify the fatigue strength at the development stage. Bogie system consists of bogie frame, suspensions, wheel-sets, braking system and transmission system. Among these components, the bogie frame is most significant component subjected to the whole vehicle and passenger loads. In this study, the bogie frame for the standard EMU power car is evaluated to the static and fatigue strength. And, the evaluation method is used the JIS E4207 specification throughout the FEM analysis and static load test. The static and fatigue test results for the standard EMU bogie frame of power car has been appeared very safety and stable for the design load conditions.