• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.1
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• pp.118-123
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• 2000

This paper describes the characteristics of a newly suggested arc-inducing driven rod with needles which could effectively spread out both the failure current with power frequency and the lightning current. The structural characteristic of the driven rod was that needles were attached on the surface of the conventional shaped driven rod and the driven rod with needles was installed inside of a copper pipe.As a result of analyzing the characteristics of this suggested driven rod when it was employed as the driven rod of an arrester in distribution system, it was verified that the primary voltage of the arrester was reduced by effectively exhausting the electrical energy since the arc occurred between the needle and the copper pipe.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.9
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• pp.1571-1576
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• 2016

A Tesla coil is an electrical resonant transformer circuit invented by Nikola Tesla in 1891. It is used to produce high-voltage, low-current, high frequency alternating-current electricity. Tesla coil can generate a long streamer with several million volts of electricity as a high voltage device. It is basically consists of a voltage transformer, high voltage capacitor, spark gap, primary coil, secondary coil and toroid. It is difficult to appear in the output size of the streamer is controlled by the spark gap. The general decision method of the length of streamer is to display the electric output in accordance with the design specifications in initial development plan. Design specifications and the electric output is determined by the application of facilities. In this paper the spark gap is replaced with periodic switching semiconductor device to control output voltage easily in order to apply overvoltage protective circuit due to a secondary coil and a performance test. In these days, their main use is for entertainment and educational displays of the museum, although small coils are still used as leak detectors for high vacuum systems.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1489_1490
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• 2009

Ground impedance is changed according to frequency of the current injected into the grounding system. Because the lightning surge gives a broad frequency spectrum from some ten Hz to a few MHz, frequency dependance of ground impedance must be evaluated. In this paper, we have constructed 10m, 30m, 50m counterpoise and evaluated frequency dependance of ground impedance. Also we have evaluated frequency dependance of ground impedance according to current injection point. As a result, long counterpoises have low ground resistance, but ground impedances of those are significantly increased in the range of high frequency. In the case that currents are injected into the center of counterpoise, the ground impedance is most lower than any other injection point. Also, additory ground rod of 1.8m long affect ground impedance decrease.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1465-1466
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• 2006

The monitoring and diagnosing technique for lightning arresters is important to assure the reliability of power supply in GIS-substation. In this paper, we described the implementation of an expert system for GIS arrester facilities. The proposed system consists of a data acquisition module (DAM), a wireless communication module, and a personal computer. The DAM detects system voltages, total leakage currents and its harmonic components, and includes an algorithm to calculate the resistive leakage current by the principle that the magnitudes of resistive leakage current are equal at the same level of the system voltage applied to the arrestor. Also, we designed a surge event detection circuit which can acquire the date, the polarity, and the amplitude of surge events. All the acquired data are transmitted after correction by many algorithms to the remote station through the ZigBee protocol. The expert system is based on the Jave Expert System Shell (JESS) and make more reliable decision by using an exclusive inference process.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2006.11a
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• pp.193-196
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• 2006

The meaning of the color which has from modern interior space has played important role, i.e. color itself Is the concept creation tool as well as the unique expression sphere in field of interior space far away from fixed idea relevant to the existing color which was only simple decoration or secondary element in space. Thus, this current work expresses that the color is related with decoration effect as well as basic designed-conceptual work process including the space is formed. Furthermore, through the side-composition with color, It activates the various space aspect perceptually, which created the colorful environment in using lightning, reflection of glass and penetrated nature etc. The keyword on color concept is as like various aspects, third dimension, non-materiality and symbolical meaning. In addition, it provides the color space equipped with functionality and artistry capable to arouse the diverse sensual capacity to space users on default of color image language.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2007.05a
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• pp.67-70
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• 2007

The meaning of the space planning which has from modern interior space has played important role, space composition planning itself is the concept creation tool as well as the unique expression sphere in field of interior space far away from fixed idea relevant to the existing space which was only simple division or secondary element in design. Thus, this current work expresses that the space-Function is related with space-division as well as basic designed-conceptual work process including the space is formed. Furthermore, through the side-composition with form, it activates the various space aspect perceptually, which created the visual environment in using lightning, reflection of glass and penetrated nature etc. The keyword on elevation design concept is as like various aspects, third dimension, non-materiality and symbolical meaning. In addition, it provides the color space equipped with functionality and artistry capable to arouse the diverse sensual capacity to space users on default of image language.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1822-1824
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• 1996

Damage and upset of control and communication equipment due to transient overvoltages which occur due primarily to internal switching surge and external lightning surge are an important problems in electromagnetic compatibility(EMC). In this paper, we analyzed operation characteristic of metal oxide varistor widely used low voltage AC line using the electromagnetic transients program(EMTP) and compare it with experimental results and also, we modeled combination generator producing $1.2/50{\mu}s$ open circuit voltage and $8/20{\mu}s$ short circuit current as a source which is critical in calculating operation characteristic. Simulation results showed that most of Transient energy consumes at MOV located in service entrance side than load side, and it showed similar to experimental results. Therefore, entrance side MOV should be selected more energy capacity than that of load side MOV.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.5
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• pp.773-782
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• 2008

This paper describes the method for proper location of protective equipment in underground distribution cable through field test and analysis at testing lines. To prove the reliability for analysis simulated by EMTP/ATPDraw, the testing results obtained by the real test and the analysis for the same test lines were compared each other. The accuracy of analysis was proved by the comparison. Over voltages were measured and analyzed at each point of cable and switches in case of which lightning surge current was applied. The analysing method was applied to real distribution systems to select the proper location of protective equipment. It is evaluated that the location of protective equipment was properly selected.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.470-471
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• 2008

SVL is installed at underground transmission system to protect cables and insulation joint-box from overvoltages caused by lightning, switching, and line-to-ground fault. Domestic underground power system adopts cross bonding type to reduce the induced voltage at sheath, but single-point bonding is required depending the system installation configuration. SVL can be easily broken by overvoltages induced at joint-box because single-point bonding has uneffective system structure to extract fault current. ANSI/IEEE recommends Parallel Ground Continuity Conductor(PGCC) to prevent SVL breakdown. In this paper, EMTP simulation is performed to analyze effects on SVL under PGCC installation when single-line-to-ground fault occurs. The result shows that PGCC and short single-point bonding distance can reduce overvoltages at SVL.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.2046-2047
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• 2008

본 논문에서는 가공 배전선로에 사용되고 있는 피뢰기의 상태 진단을 위한 누설전류 분석기법에 대해 기술하였다. 현장에서 다양한 환경 스트레스를 받고 있는 피뢰기는 점차 열화가 진행되어 선로 고장의 원인이 되므로 이를 사전에 검출하여 고장을 예방하는 것이 중요하다. 피뢰기 이상을 효과적으로 검출하는 방법의 하나로 사용되고 있는 누설전류 측정방법에 대해 평가하였다. 피뢰기 누설전류는 측정 환경에 영향을 받을 수 있기 때문에 현장 측정한 결과와 실험실에서 측정한 결과를 비교하여 분석하여 환경영향을 보정하여 판단하는 방법을 고려하였다. 또한 온도에 따른 누설전류 값의 변화를 분석하여 누설전류에 의한 피뢰기 상태 판단 근거를 마련하였다. 이를 위해 현장에서 설치 운용되고 있는 피뢰기를 지역별로 고르게 발취하여 측정 분석하였다.