• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.516-517
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• 2007

Because forest fire can give a serious damage to overhead conductors, the thorough understanding about sag behavior of burned conductor is very important in maintaining the transmission line safely. Therefore, a systematic investigation was carried out by heating method. As the heating temperature increases, drastic change of tensile strength of Al wire due to the softening of Al wire occurred. When Al wire is exposed to the flame(about $800^{\circ}C$) during only 13 seconds, the remained tensile strength of Al wire showed under 90%. and then sag of overhead conductor become deteriorated. The detailed results will be given in the text.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1328-1333
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• 2004

This paper presents a suggestion for improvement of tension balancer in trolly wire system. In the overhead trolly wire systems, one of the most things is tension balancer. Because it can be automatically adjusted tension for expansion and contraction of overhead catenary system. In this paper, we introduce and suggest spring tension balancer(STB).

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.9
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• pp.1605-1609
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• 2016

The measurement of current collection performance between pantograph and contact wire of overhead catenary system is intended to prove the safety of operation and the quality of the current collection system. The results of interaction performance of current collection system are required for approving with commercial operation on railway lines. The methods of interaction performance of current collection system are defined on interactional standards such as IEC 62486 and EN 50317. In this paper, the interaction performance is evaluated by the percentage of arcing on Honam high-speed line and the results are used for adjustment of the overhead catenary line structure. The experimental results in Honam high-speed line confirm that the duration of an arc lasting longer 25 ms between pantograph and contact wire was depended on the conditions of overhead contact line after installation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.9
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• pp.868-871
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• 2008

We propose an optical-based measuring instrument of catenary system in electric railway. This system was made to utilize line scan camera as inspecting system to measure the stagger and height of overhead contact wire in railway and composed with optical type source and FPGA-based image acquisition system with PCI slot. Vision acquisition software has been used for the application to programming interface for image acquisition, display, and storage with a frequency of sampling. To check the validity of our approach for the intended application, we monitored height and stagger in the overhead wire of a high-speed catenary system in Korea. The proposed optical-based measuring instrument to measure the contact wire geometry such as the hight and stagger shows promising on-field applications for online condition motoring. We expect that a new generation of real-time instruments with demanding various conditions motoring requirement in railway can be easily integrated into optical-based measuring instrument system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.601-602
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• 2005

In the cold and temperate regions of Korea the icing and ice coats on 25 kV overhead contact wire during winter is a very serious problem. This generates shocks at the mechanical interface of the collecting strips of the pantograph and the contact wire and extra electrical resistance, which may affect quality of current collection at the contact wire / collecting strips of pantograph interface. De-icing operations should be performed just before train operation to avoid the formation of another ice layer. This paper presents temperature analysis of the de-icing system which could be applied to the overhead contact wire of railways.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.5
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• pp.415-420
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• 2013

The new recycling technology for aged Aluminum wires in overhead conductor have been carried out. We are attempting to develop remanufacturing method for them for more effective way of recycling in stead of its conventional remelting process. The weld of aged aluminum wires play a vital role in remanufacture process. The paper investigates the mechanical properties during cold welding process of aged Aluminum wire. The tensile tests and microscopic analysis results are discussed to underscore the hardening features of welded aluminum wire. Various graphs are presented accompanied by discussion about their relevance on the process.

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.468-470
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• 1999

Using the EMTP(Electro Magnetic Transient Program) for the analysis of lightning direct voltage on the railway system, the shielding effects of overhead grounding wire on the railway were studied quantitatively. Installation of overhead ground wire and sap-type arrester such as s-horn provides a 6.6kV HV distribution line with goof protection effects. Even severe lightning induced voltage were create, 6.6kV HV lines can be withstand.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.1
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• pp.161-167
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• 2001

The overhead transmission wires operating both at warm temperature and tighten state for a long period of time in a power transmission plant are degraded by air pollution, wind, creep and slip between steel wire and aluminium conductor. The objective of this study is to investigate to investigate the characteristics of fatigue properties with tension and bending loading of a high carbon steel wire. The fatigue behaviors have been carried out by tension-tension, 4 points bending and 3 points bending loading. In the present study, a conventional fatigue strengths between 4 points bending and tension-tension fatigue were determined by Gerber, Sorderberg and Goodmans theory and we investigated S-N diagram for bending and tensile loading.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.11a
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• pp.297-299
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• 2004

In multi-ground distribution system, overhead ground wire and neutral wire are parallel connected to offer the electrical power energy and protect damage of lightning strokes. Therefore a case where the two wires become single wire, the power company can get the benefit such as installation cost saving and line fault protection by simplify of distribution line. In this paper we describe the result of impulse test in both system ; one is the present power system the other is unified power system parallel connected overhead ground wire and neutral wire. As a result of this impulse test, the present power system get lower impulse voltage than the unified power system.

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.274-279
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• 2000

The overhead transmission wires operating both at warm temperature and tighten state for a long period of time in a power transmission plant are degraded by air pollution, wind, creep and slip between steel wire and aluminium conductor. The objective of this study is to investigate a high carbon steel wire. We tested for basic mechanical properties and 3 types fatigue behavior, tension-tension, 4 points bending and 3 points bending fatigues. In this study, a conventional fatigue strengths between 4 points bending and tension-tension fatigue were determined by Gerber, Sorderberg and Goodman's theory and we investigated S-N diagram for bending and tensile loading.