• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.1073-1074
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• 2006

In this paper, we perform a simulation to verify the earth resistance values in Common Earth Network. The simulation is performed on the assumption that certain shorts are occurred in common earth network. Furthermore, from the result, we confirmed that very small earth resistance values in common earth network are given, by carrying out practical measurements in railway sections where common earth network is composed. From the effect, we could discover that the construction of common earth network is in a disadvantageous position on the financial aspect, while it is the most desirable way of construction for the purpose of Earth.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.269-274
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• 2005

This paper is studied on earth network configuration when common earth is applied to electrified railway system. And the permitted capacity of buried earth cable used for configuring common earth network and application plan of existing individual earth system when common em1:h network is applied to existing electrification line improvement are studied. For this, the configuration of common earth network is examined according to the SNCF regulation, and the interface between common earth and individual earth is analysed on the basis of the existing track circuit used in electrified line.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권9호
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• pp.509-514
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• 2002

The aim of this research is to find out how the common earth network affects the level of the traction return current in the $2{\times}25 kV$ Power Supply System. The traction return current plays a significant role in the operation of the facilities near the rails. It is shown that the common earth network in the $2{\times}25 kV$ power supply system not only minimizes the level of the traction return current, but also increases the safety of the working crew on the railways. In order to determine the relationship between common earth network and the traction return current, we investigated the earth system of the Gyongbu High Speed Line that is constructed following the SNCF regulations. We carried out the field test in the Osong station. The results of the test show that the common earth network minimizes the effect of the traction return current. We also find that the simulated results are very similar to the test results. We concluded that the results of the test can be applied for the rest of the Gyongbu High Speed Line under construction.

• 전기학회논문지
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• 제66권5호
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• pp.877-884
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• 2017

A method of common earth, which is proposed by French Railway(SNCF) and is applied to high speed railway, minimizes the effect of the traction return current from tracks so that trackside electric devices can be protected and operation and maintenance staffs are kept out from injury in an electric railway environment. According to it, all the new domestic electric railway lines are replaced from existing individual earth method to the common earth method. In this paper, we analyze the correlation between common earth method and traction return current to prove whether the common earth has surely contributed to minimize the effect of the traction return current. The analysis was done based on the measurement of the traction return current at the domestic high speed railway line.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.53-55
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• 2005

In electrical railway system, power supplied to electrical locomotive by catenary is returned to sub-station on track. The current returned to sub-station on track is return current, which is an essential factor for the safety of the wayside electrical equipment and maintenance staff. Therefore, earth system acts an important role to protect wayside electrical equipment and maintenance staff against return current. In general, individual earth system protects partially the electrical railway system, but common earth system does the whole electrical railway system and minimizes the flow of return current. In this paper, we are compared the effect of return current according to earth type by actual measurement in existing electrical railway system. The measurement was conducted at Shinchungju sub~station in high speed trains, and Guro sub-station, which is electrified section in classical line.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.190-195
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• 2008

Surge proof equipment is an installation to make surge flow on the ground promptly so as to reduce surge-related damage on infrastructure, not to prevent surge from falling down on infrastructure directly. Compared with classical line individual earth, High speed line common earth has higher surge characteristic and plays a significant role to prevent infrastructure damage and injuries from surge, or short circuit accident between 25kV catenary and rail. In this paper, we analyzed the case of accident that caused communication/signaling system impaired while a tractor crossing level crossing at Honam line; in addition, we examined the accident reduction measures to minimize injury and property damage from cutting accidents with respect to common earth network.

• 전기학회논문지
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• 제67권6호
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• pp.702-707
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• 2018

In case of Lighting occurs in Domestic combined distribution line, normally the voltage for the neutral line increase dramatically. General connection for underground cable is bundled common earth type so the lightning over voltage increase at the concentric-neutral line is not big enough to give impact on cable sheath. But in case of Non bundled common earth type it is necessary to analyze the phenomena on cable sheath caused by lightening overvoltage. Especially pole and cable joint are the core factor to consider. In this paper concrete pole and cable joint were evaluated in case of Non bundled common earth type combined distribution Line. EMTP simulation model has been designed and several case study were made. Also several experimental test were made to verify the simulation result.

• Journal of Photoscience
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• 제9권2호
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• pp.170-173
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• 2002

Space is full of energetic events emitting high-energy radiations which may be fatal to all living things unless protected. The present paper briefly describes high-energy photons and particles incident on Earth surface and their common properties toward living things. Role of radiation played in evolution of life and earth environment will be presented.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전력기술부문
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• pp.344-346
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• 2001

The sharing of common corridors by electric power transmission lines and pipelines is becoming more common place. However, such corridor sharing can result in undesired coupling of electromagnetic energy from the power lines to the near facilities. During a fault on any of the transmission lines, energization of the earth by supporting structures near the fault can result in large voltages appearing locally between the earth and the steel wall of any nearby pipeline. This paper presents the outline of the tower footings for the transmission lines having been used in KEPCO and analyzes the earth resistance for operation method of the tower footing, that is contact presence for the anchor and reinforcing rob of the tower and foundation presence of the underground wiring.

• 한국산학기술학회논문지
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• 제11권12호
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• pp.4968-4974
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• 2010

전기철도는 전차선을 통해 차량을 구동할 수 있는 전력을 공급하며, 공급된 전류는 선로 및 접지망을 통해 변전소로 귀환한다. 국내의 경우, 이러한 귀선전류에 영향을 주는 접지망 구성은 대부분 단독 접지방식을 사용하였으나, 경부고속선의 도입과 함께 공동 접지방식의 개념이 전기철도에 적용되었다. 본 논문에서는 고속철도의 기존선 운행을 위한 전철화 구간에서 측정, 분석한 귀선전류를 기반으로 전철화 구간에 있어서의 접지방식과 귀선전류의 관계를 분석하였다. 이러한 분석은 경부고속선 궤도회로에서 측정된 귀선전류 분석값과 경부고속선과 기존선 전철화 구간의 접지방식 비교에 따른 귀선전류의 예측값을 활용하였다.