• Title/Summary/Keyword: High Contact

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A Modeling and Simulation Implementation on the Power Line Disturbances by Loss of Contact for the High-Speed Railway Vehicle (고속전철 주행시 이선에 따른 전원외란 현상 모델링 및 시뮬레이션 구현)

  • Kim, Jae-Moon;Kim, Yang-Soo;Chang, Chin-Young;Gimm, Yoon-Myoung
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.1137-1142
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    • 2008
  • In this paper, an effect on power conversion unit in high-speed railway vehicle by loss of contact between a catenary system and pantograph suppling electrical power to high-speed railway vehicle are investigated. One of the most important needs accompanied by increasing the speed of high-speed railway vehicle is reduced that arc phenomenon by loss of contact brings out EMI. in case of high-speed railway vehicle using electrical power, as comparison with diesel rolling stock, PLD(Power Line Disturbance) such as harmonic, transient voltage and current, EMI, dummy signal injection etc usually occur. To analysis the effect on loss of contact, it is necessary electrical modeling system between the contact line and the pantograph according to the loss of contact. Therefore analytical model of a contact line and a pantograph is constructed to simulate the behaviour of loss of contact. The reliability of the modeling system is verified by simulation implementation on kinds of loss of contact.

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A Study on the Measurement of Contact Force of Pantograph on High Speed Train

  • Seo Sung-Il;Cho Yong-Hyun;Mok Jin-Yong;Park Choon-Soo
    • Journal of Mechanical Science and Technology
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    • v.20 no.10
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    • pp.1548-1556
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    • 2006
  • Appropriate contact force is required for the pantograph on the high speed train to collect current from the catenery system without separation. However, at high speed, large aerodynamic lifting force is generated by the contact plate and the body of pantograph, which may cause wear of the contact wire. In this study, to confirm the interface performance of the pantograph on Korea High Speed Train, a method to measure the contact force of the pantograph was proposed and the related measuring system was developed. The forces acting on the pantograph were clarified and a practical procedure to estimate the forces was proposed. A special device was invented and applied to measure the aerodynamic lifting force. Measured contact forces were displayed by the developed system and evaluated based on the criteria.

A Study on the Measurement of Contact Force of Pantograph of Korean High Speed Train (한국형 고속전철 집전장치 접촉력 계측에 관한 연구)

  • Seo, Sung-Il;Cho, Yong-Hyun;Park, Choon-Soo;Mok, Jin-Yong
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.1453-1457
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    • 2003
  • The pantograph for Korean High Speed Train was developed by home-grown technology. In this study, a system to measure the contact force of pantograph is developed and installed on the prototype high speed train, Contact force prevents the pantograph from separating from the catenary. However, excessive contact force causes rapid erosion of catenary. The contact force can be divided into lift force and spring force. Contact force measurement is conducted while the train runs on the test track. The lift force is measured by the load cell on the roof separately and combined with the spring force of pan-head to form the contact force. Measured results show that the contact force of the pantograph of Korean High Speed Train is below the upper limit regulated by the high speed train standards. The contact force measuring system provides data to evaluate safety of the catenary system.

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Analysis of conducted EMI source on powering mode of next generation high-speed train (차세대 고속전철 주행에 따른 전도성 노이즈 요인분석)

  • Kim, Jae-Moon;Kim, Sei-Chan;Kim, Hak-Man
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.948-949
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    • 2008
  • In this paper, an effect on power conversion unit in next generation high-speed train by loss of contact between a contact wire and pantograph supplied electrical power to high-speed train are investigated. One of the most important needs accompanied by increasing the speed of high-speed train is reduced that arc phenomenon by loss of contact brings out EMI. To analysis of conducted EMI source on powering mode of next generation high-speed train, it is necessary electrical modeling system between the contact wire and the pantograph according with loss of contact. Therefore analytical model of a contact wire and a pantograph is constructed to simulate the behaviour of loss of contact. The reliability of the modeling system is verified by simulation implementation on loss of contact.

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Low-cost Contact formation of High-Efficiency Crystalline Silicon Solar Cells by Plating

  • Kim D. S.;Lee E. J.;Kim J.;Lee S. H.
    • New & Renewable Energy
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    • v.1 no.1 s.1
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    • pp.37-43
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    • 2005
  • High-efficiency silicon solar cells have potential applications on mobile electronics and electrical vehicles. The fabrication processes of the high efficiency cells necessitate com placated fabrication precesses and expensive materials. Ti/Pd/Ag metal contact has been used only for limited area In spite of good stability and low contact resistance because of Its expensive material cost and precesses. Screen printed contact formed by Ag paste causes a low fill factor and a high shading loss of commercial solar cells because of high contact resistance and a low aspect ratio. Low cost Ni/Cu metal contact has been formed by using a low cost electroless and electroplating. Nickel silicide formation at the interface enhances stability and reduces the contact resistance resulting In an energy conversion efficiency of $20.2\%\;on\;0.50{\Omega}cm$ FZ wafer. Tapered contact structure has been applied to large area solar cells with $6.7\times6.7cm^2$ in order to reduce power losses by the front contact The tapered front metal contact Is easily formed by the electroplating technique producing $45cm^2$ solar cells with an efficiency of $21.4\%$ on $21.4\%\;on\;2{\Omega}cm$ FZ wafer.

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Implementation Technique of Real-time Monitoring System for High-Speed Rail Contact Wire with High Tension (고속철도 전차선로 고장력 실시간 모니터링 기술 구현)

  • Cho, Yong Hyeon;Park, Young;Jung, Hyun Jin
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.8
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    • pp.1256-1261
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    • 2015
  • Along with the increase of railway catenary system operation speed to 400 km/h, there have been growing demands for good quality current collection systems that satisfy quality standards as well as criteria for safe working. Retaining uniform elasticity tension of contact wires is essential in maintaining high quality contact between pantograph and OCL (Overhead Contact Line) of current collection systems in high speed railways. Therefore, the tension of contact wire must be kept within tight tolerance limits in both working conditions and adverse weather conditions of catenary system. In accordance with these conditions, this paper presents a real time monitoring system for the tensioning device of the newly installed catenary system on the special route of Honam high speed line for 400 km/h operation. For the verification of the true value of tension of contact wires, we have developed ring-type tensioning sensors which were installed on supporting points of mast which compose the catenary system. According to the field test performed on the Honam high speed line catenary system, variation of tension was measured accurately in real-time.

Development of an Uplift Measurement System for Overhead Contact Wire using High Speed Camera (고속카메라를 이용한 전차선 압상량 검측 시스템 개발)

  • Park, Young;Cho, Yong-Hyeon;Lee, Ki-Won;Kim, Hyung-Jun;Kim, In-Chol
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.10
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    • pp.864-869
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    • 2009
  • The measurement of contact wire uplift in electric railways is one of the most important test parameters to accepting the maximum permitted speed of new electric vehicles and pantographs. The contact wire uplift can be measured over short periods when the pantograph passes monitoring stations. In this paper, a high-speed image measurement system and its image processing method are being developed to evaluate dynamic uplift of overhead contact wires caused by pantograph contact forces of Korea Tilting Train eXpress (TTX) and Korea Train eXpress (KTX). The image measurement system was implemented utilizing a high-speed CMOS (Complementary Metal Oxide Semiconductor) camera and gigabit ethernet LAN. Unlike previous systems, the uplift measurement system using high speed camera is installed on the side of the rail, making maintenance convenient. On-field verification of the uplift measurement system for overhead contact wire using high speed camera was conducted by measuring uplift of the TTX followed by operation speeds at the Honam conventional line and high-speed railway line. The proposed high-speed image measurement system to evaluate dynamic uplift of overhead contact wires shows promising on-field applications for high speed trains such as KTX and TTX.

Contact Stress Analysis of Helical Gear for Turbo Blower (터보블로워용 헬리컬 기어의 접촉응력 해석)

  • Hwang, Seok-Cheol;Lee, Dong-Hyong;Park, Young-Chul;Lee, Kwon-Hee
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.10 no.2
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    • pp.90-95
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    • 2011
  • This paper presents the study on the contact stress analysis of a pair of mating helical gears for turbo blower during rotation. Turbo blowers need high speed rotation of impeller in structure and high rate gear ratio. The use of helical gear indicated that noise was an important problem when the application involves high speeds and large power transmission. An example is presented to investigate the variation of contact stress on a pair of mating gears with contact positions. The variation of contact stress during rotation is compared with the contact stress at the lowest point of single tooth contact(LPSTC) and AGMA Equation for contact stress. In this study, the gear design considering the contact stress on a pair of mating gear is more severe than that of AGMA standard.

The Electrical properties of Al/TiN/Ti Contact at Submicron contact(2) (Al/TiN/Ti 전극의 Submicron contact에서의 전기적특성(2))

  • Lee, C.J.;Eum, M.J.;Ra, Y.C.;Kim, S.J.;Sung, M.Y.;Sung, Y.K.
    • Proceedings of the KIEE Conference
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    • 1995.07c
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    • pp.1069-1071
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    • 1995
  • The electrical properties of Al/TiN/Ti contact are investigated at submicron contacts. The contact resistance and contact leakage current are dependent on metallization, surface dopant concentration, semiconductor surface treatment and contact plug ion implantation. In this paper, the contact resistance and contact leakage current are studied according to surface dopant concentration, semiconductor surface treatment and contact plug ion implantation at 0.8 micron contact. The contact resistance and contact leakage current increases with increasing substrate ion concentration. HF cleaning represents high contact resistance but low contact leakage current while CDE cleaning represents low contact resistance but high contact leakage current. Contact plug ion implantation decreases contact resistance but increases contact leakage current. Specially, RTA represents good electrical properties.

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Characteristics of Friction Torques and Lubrication in High Speed Angular Contact Ball Bearings (고속 앵귤러 콘택트 볼베어링의 마찰 토크 및 윤활 특성)

  • 반종억;김경웅
    • Tribology and Lubricants
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    • v.13 no.4
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    • pp.47-52
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    • 1997
  • Friction torques, electrical contact resistances and bearing temperatures were measured on high speed angular contact ball beatings for the spindle of machine tools. The test bearings ran with oil-air lubrication at the thrust loads from 320 N to 1920 N and at the rotational speed of up to 12000 rpm. Electrical contact resistances between balls and races were measured to evaluate the formation of the lubricant film in the contact area. The test results with sufficient lubrication showed that the variations of friction torques were sensitive to the thrust loads and the rotational speeds, and that the friction torques were higher than those with insufficient lubrication. With insufficient lubrication and high thrust loads, the collapse of the lubricant film was detected even at a high rotational speed. It was concluded that these high speed beatings to run in condition of fluid lubrication should require monitoring not only the temperature increase of the bearing but also the lubricant film formation in contact areas resulting from the change in the applied load and the lubricant amount.