• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.3
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• pp.486-491
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• 2011

Since Korea has high accident rate for the electrical shock than other advanced countries, it causes very serious problems. In this paper, a new classification method for analyzing electricity accidents is proposed, which is based on the microscopic view while existing methods have been based at the macroscopic view point. Electrical accidents cases can be mainly divided by three cases, which are from live works, incompleteness of the grounding system and imperfectness of the safety education and public relations. New data format of electrical shocks are proposed in the environment of smart grids.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.10
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• pp.1881-1887
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• 2009

This paper discusses the effects of ECC (Earth Continuity Conductor) for reducing the level of induced sheath overvoltages at the single point bonded section of combined transmission lines which are mixed underground power cable with overhead line in one T/L. In previous papers, the characteristics of ECC on only underground power cable systems were sufficiently analyzed. However, the result of only underground power cable systems are totally different from that of combined transmission lines because ECC is commonly grounded with overhead grounding wire at mesh of cable head. Therefore, in this paper, the installation effects of ECC have been variously analyzed considering the three kinds of fault positions, cable formation of duct and trefoil, spacing between phase conductor and ECC, and the change of overhead transmission line section length on 154kV combined transmission line. Finally, simulation results show that ECC can effectively reduce the induced sheath voltage.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.05a
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• pp.95-99
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• 2004

A systematic approach of measurement, modeling and analysis of grounding system impedance in the field of lightning protection systems is presented. The measurement and analysis of ground impedance are based on a computer aided technique. The magnitude and phase of ground impedance were measured and analyzed by the modified fall-of-potential method and the proposed computer program algerian using the waveforms of the test current and potential rise. The theoretical analysis of ground impedance were performed with the equivalent circuit models, and the theoretical results were compared with the measured data.

• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.71-74
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• 2003

Fall-of-potential method is used usually to measure the ground impedance of large scale grounding system exactly. Because the interlinked magnetic flux between closed loops to inject test current and to measure potential rise is existed in E-P-C straight line arrangement, mutual(or inductive) coupling influences greatly on the measurement correctness. Measurement errors produced from inductive coupling could be reduced by the arrangement methods of auxiliary electrodes. Right angle or P-E-C order arrangement methods were effective to reduce the inductive coupling and the decrease degree of measurement error was analysed as quantitative through an experiment.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.05a
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• pp.63-66
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• 2009

Lighting currents are one of major influences on the dynamic performance of ground electrodes. High lighting current intensity changes in the dynamic grounding performance due to ionization of the soil and very fast fronted pulses. The previous analysis has often been based on quasi-static approximation that is not applicable to very fast fronted pulses. To extend the analysis to fast fronted pulses in this paper, the full-wave analysis method based in the rigorous electromagnetic-field theory approach is used and the effects of the ionization of the soil me disregarded. Based on the simulation results, the empirical formulas applicable for slow and very fast fronted lightning current pulses me reviewed; therefore the validity of the theoretical approach is verified through comparison between the calculated and measured results.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.08a
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• pp.37-40
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• 2002

Ground connection began by experimenting lightning with the use of a kite and it means electric appliances, communication equipments, measuring instruments and so on connecting the Earth in order to flow away overcharged electricity. There are two kinds of earth connection: Power Ground and Signal Ground. Power Ground is for preventing an electric shock and in general there's no current in the connector. However in an accident, there's a quick flow of electricity out to the Earth. Signal Ground is not only for the safety of appliances but also for the safety of equipment operation. This paper is about connection for noise and interference reduce in order to prevent wrong operation and distortion of signal in the electrical appliances which can take place in cable TV.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2023.11a
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• pp.200-201
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• 2023

전기차 보급이 늘어나면서 그만큼 화재의 발생이 늘어나고 있다. 화재 발생률로만 보면 내연기관 차량보다 더 높다고 볼 수 없다. 하지만 전기차 화재는 폭발성이 강하고 순식간에 인접한 물체에 옮겨붙으며 화재 진압이 어렵다는 특성을 보이고 있다. 전기차 화재의 위험성에도 불구하고 산업통상자원부에서는 지하 주차장 비율이 높은 환경에서 지상 주차장 설치를 강제한다면 친환경 자동차 보급에 저해가 되기 때문에 법률을 개정하는 것을 주저하고 있는 실정이다. 외국에서도 전기차는 지상주차장을 우선으로 하는 추세이다. 이에 본 연구는 공동주택 등에서 전기차 주차장을 지상에 별도로 설치하는 등 안전을 도모한 법률과 조례안을 구상하고자 한다.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2023.11a
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• pp.135-136
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• 2023

본 논문에서는 건설현장 중 토목건설현장의 임시설비 기계, 기구 등의 접지저항치를 안전하게 최대한 낮추어 감전 재해율을 저감하기 위한 연구이며, 토목건설현장 주변의 설치되어 있는 기존 시설물 흙막이, 가드레일, 개천의 물 등을 이용한 접지시설을 통해 각종 사용되는 임시설비의 감전재해 저감을 위함이다. 최근 건설현장 안전관리에 대한 임시설비 등의 기계화, 안전장치 등의 발전에도 불구하고, 건설현장의 감전 재해율은 크게 감소하지 않는 추세라 이를 보완, 보호하기 위해 본 논문을 작성하였다. 건설현장 중 접지시설 설치가 곤란하고 어려운 토목건설현장 대상으로 감전재해 형태의 예방효과를 별도의 재료를 필요로 하지 않고 현장 주변 시설물 대상을 이용한 접지시설을 설치하여 실제로 실험을 통해 접지저항치에 대해 측정하였다.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.6
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• pp.1108-1114
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• 2016

The cause of failure in the AT feeding system is divided into grounding, short-circuit of feeding circuit and internal faults of the railway substation. Since the fault current is very high, real-time current is detected and the failure must be immediately removed. In this paper, a new DC offset elimination filter that can remove component to decrease in the form of exponential function using low-pass filter was proposed in order to extract the fundamental wave from distorted fault current. In order to confirm the performance of the proposed filter method, AT feeder system was modelled by simulation tool and simulations were performed under various conditions such as fault location, fault resistance and fault voltage phase angle in case of trolley-rail short-circuit fault. When applying the proposed DC-offset removal method, it can be seen that the phase delay and gain error did not appear.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.367-370
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• 2008

In this paper, the effects of the position and the angle of the auxiliary probes on the measurements of the low frequency ground impedance with the fall-of-potential method are described iud the testing techniques to minimize the measuring errors are proposed. The fall-of-pot ential method is theoretically based on the potential and current measuring principle and the measuring error is primarily caused by the position and angle of auxiliary probes. In order to analyze the characteristics of ground impedance due to the location of the potential probe, ground impedances were measured in case that the distance of current probe was fixed at 50[m] and the distance of potential probe was located from 10[m] to 50[m]. Also, the potential robe was located at 30[$^{\circ}$], 40[$^{\circ}$], 60[$^{\circ}$], 90[$^{\circ}$], and 180[$^{\circ}$]. The results could be help to determine the location of potential probe when the ground impedance was measured at grounding system.