• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.12
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• pp.197-203
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• 2014

When the lightning current is injected to the ground system of information and communication facilities, analysis of the transient potential rise in the ground system is one of main factors to effectively design the ground system. The performance of grounding systems is normally estimated with the grounding impedance and the transient potential rise which represents the electrical characteristics of the grounding system. The method for calculating the grounding impedance depending on the injection point of the lightning current was proposed. The delta-gap source model was proposed to calculate the grounding impedance in the case that the lightning current is injected to the center of the horizontal ground electrode. A new program which is possible to apply the frequency-dependent soil parameters using the Debye model was developed, because a commercial program for analyzing the performance of the grounding system can not apply to the frequency-dependent soil parameters. The experiment was carried out to confirm the availability of the simulation results with the same condition. Finally, the transient potential rises of a horizontal ground electrode depending on the lightning current waveforms were analyzed by using the results of the grounding impedance which is associated with the frequency-dependent soil parameters.

• 한국정보통신설비학회:학술대회논문집
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• 2004.08a
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• pp.219-222
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• 2004

정보통신설비 접지의 기본적인 방법은 각 설비에 대한 접지계통간에 아무런 접속이 되지 않는 것이다. 이것을 독립접지라고 하는데 이렇게 할 경우에 어느 한 접지체로의 이상전류 유입에 따른 대지전위 상승에 의하여 다른 접지체에 상승유도전압(rising potential)이 걸려 해당 설비에 손상을 입힐 수 있으므로 각 접지체 간에 적절한 이격거리를 확보해 주어야 한다. 그러나 설치공간상의 제약을 받게 되므로 때로는 접지계통간에 접속시켜 등전위화를 이룸으로써 이상전류 유입에 따른 영향을 배제할 수 있다. 이것을 공통접지라고 하는데 일본의 기술 영향을 받은 우리나라는 오랜 동안 독립접지 방식이 안정된 방법으로 인식해와 공통접지에 대한 우려를 가지고 있다. 그러나 최근에는 ITU-T의 접지 관련 표준화 활동에서 중요한 역할을 수행하고 일본에게 있어서도 독립접지로서 수용할 수 없는 현실적 환경 문제의 개선을 위하여 통신센터빌딩등에 적용할 수 있는 통합적인 공통접지 시스템 기술을 개발하고 있다.

• Information and Communications Magazine
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• v.15 no.8
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• pp.93-107
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• 1998

정보통신분야의 눈부신 발전 및 확산에 따라 최근의 건물에는 OA기기, 통신기기, 빌딩관리시스템기기, 보안시스템 기기 등이 도입되고 있으며 이들 기기는 동작 전류가 매우 작아 원하지 아니하는 전류에 의해 기기의 파괴, 오동작, 잡음 등의 장애가 발생한다. 그러나 이러한 기술적 변화에 따른 영향으로부터 대응할 수 있는 통신용 접지에 대해서는 소홀히 한 것이 사실이었다. 이에 국제표준화, 국내 접지현황 및 문제점을 고찰하고 인텔리전트 빌딩에 맞는 접지시스템 및 정보통신 설비별 세부 설치방법을 소개함으로써 국내 통신용 접지에 맞게 활용할 수 있는 계기를 마련하고, 더불어 접지의 중요성에 대한 인식전환의 계기가 되었으면 한다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.5
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• pp.62-69
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• 2010

This paper presents the dependances of transient grounding impedances of counterpoises on the soil structures and the injected point of impulse currents. The transient and conventional grounding impedances of the 25 and 50[m] counterpoises buried in the soil with different resistivity were measured and analyzed as a function of the rise time of impulse currents. As a result, the transient grounding impedances give an inductive behavior, and the trend of the conventional grounding impedances is similar to that of the transient grounding impedances. The ground resistance of counterpoises is irrespective to the injected of impulse current, but the transient and conventional grounding impedances in a short time range especially depend on the soil resistivity and position of the injected point of impulse currents.

• Electric Engineers Magazine
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• v.212 no.4
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• pp.35-41
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• 2000

전력계통 스터디를 위해 3상 단락전류 및 지락전류 계산에 대하여 수회에 걸쳐 살펴 보았다. 본고에서는 계통 지락전류 계산에 이어 접지시스템의 이해를 돕기 위해 기술적 사항을 기술하고자 한다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.2
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• pp.41-48
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• 2003

To make a efficient grounding facilities, it is very important to assume electrical potential distribution and grounding resistance previously in grounded electrode circumference, when the current flow to grounded electrode. In this paper, grounding resistance analyzed from grounding surface electrical potential in grounded rectangular electrode plate is compared to grounding resistance by theoretical expression and grounding resistance measured by simulated experiment in the water tank.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.9
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• pp.67-74
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• 2009

For the surge currents like lightning currents containing high frequency components and the abnormal currents having high frequencies which cause the EMI(Electromagnetic interference) problems for the electronic devices and communication instruments, the linear grounding electrodes have the significantly composite impedance characteristics which are dependent on the frequency of the applied current. The impedance of a grounding electrode is not lowered by expanding the dimension of the grounding electrode, and the length of grounding electrode having the minimum value of the grounding impedance for each condition of frequency and soil characteristics is existent, and it is defined as Critical length. In this paper, the critical lengths for the vertically and horizontally-buried grounding electrodes are calculated by using the distributed parameter circuit model. The propriety of the simulations has been confirmed by comparing the simulated results with the measured results.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.12
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• pp.4968-4974
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• 2010

Electrical Railroads provide electric power, which can operate vehicles, via feeder wires. And the supplied current returns to the transformer substation through lines and ground net. In domestic cases, the configuration of ground net affecting such a return current mostly uses an exclusive earth method. However, along with the introduction to Gyeongbu HSL(High Speed Line), the concept of Common Earth was applied to Electrical Railroads. In this paper, based on the return currents analyzed to be measured in the electrified sections for the operation of High Speed Rails in existing lines, we analyze the relations between earth methods and return currents in electrified sections. For analysis, we utilize the measured values of return currents measured in track circuits in Gyeongbu HSL, and predictive values of those compared to the earth methods between Gyeongbu HSL and the existing electrified sections.

• Electronics and Telecommunications Trends
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• v.19 no.4 s.88
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• pp.119-126
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• 2004

정보통신설비 접지의 기본적인 방법은 각 설비에 대한 접지계통간에 아무런 접속이 되지 않는 것이다. 이것을 독립접지라고 하는데 이렇게 할 경우에 어느 한 접지체로의 이상전류 유입에 따른 대지전위 상승에 의하여 다른 접지체에 상승유도전압(rising potential)이 걸려 해당 설비에 손상을 입힐 수 있으므로 각 접지체간에 적절한 이격거리를 확보해 주어야 한다. 그러나 설치공간상의 제약을 받게 되므로 때로는 접지계통간에 접속시켜 등전위화를 이룸으로써 이상전류 유입에 따른 영향을 배제할 수 있다. 일본의 기술 영향을 받은 우리나라는 오랜 동안 독립접지 방식이 안정된 방법으로 인식되어 공통접지에 대한 우려를 가지고 있다. 본 논문에서는 공통접지가 어떻게 활용될 수 있는지에 대하여 알아보도록 하겠다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.2
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• pp.63-68
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• 2005

This paper describes the characteristics of effective impulse ground impedance of deeply driven ground rods combined with grounding grid or counterpoises with needles. The potential rises of the test ground electrodes were measured as a function of the rise time of applied impulse currents and the effective impulse ground impedances were calculated The impulse ground impedances of deeply driven ground rods strongly depend on the rise time of impulse currents and significantly reduced by the connection of grounding grids in parallel.