• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.4
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• pp.583-588
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• 2014

In this study, there are examined to the grounding of lightning protection system and electrical continuity tests in the field. The standard for lightning protection system is different design or construction according to the characteristics of the structure. Ground is measured and compared at least four locations. According to the measured results in the field, the sampled values of the ground resistance are measured $5{\Omega}$ or less and the difference between each value is suitable as $0.2{\Omega}$ or less. The values of the electrical continuity test between ground and metal bodies are measured 3 groups such as isolated portion, the mechanical contacted portion, and the electrical continuity portion measuring $0.2{\Omega}$ or less. It is measured to be less than $0.2{\Omega}$ at all in metal bodies of underground. A metal body installed inside the structure is not isolated, but the resistance values are higher than $0.2{\Omega}$. Therefore, It must be carried out the structure having lightning protection system confirm the LPL(lightning protection level) and design the strategy.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.558-560
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• 2003

The effects of surge arresters for protection of transmission systems against direct lightning strokes have already been investigated using the digital simulation program EMTP. Distribution lines are spanned on a much large area as compared to transmission lines, and therefore, are more often susceptible to lightning strokes. This paper analyzes the overvoltages on underground cable system against direct lightning strokes to the overhead ground wire using the digital simulation. The effects of lightning protection methods, such as lowering the grounding resistance and installing the surge arrester, for preventing overvoltages on underground cable system caused by direct lightning strokes to the overhead ground wire is investigated. Several schemes have been proposed to protect underground cables. This paper summarizes the main results of a study aimed at analysis of lightning overvoltages in variety underground feeders protected by metal-oxide arresters. This study will provide insulation coordination methods for reasonable system design in 22.9kV underground cable system.

• Journal of Aerospace System Engineering
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• v.14 no.spc
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• pp.49-55
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• 2020

The average probability of a lightning strike to transport aircraft operating in airline service has been estimated to be approximately one strike in every year (or one strike per 1,000 through 20,000 flight hours). The important thing is not the probability of a lightning strike to aircraft, but the fact that aircraft is struck by lightning. Therefore, lightning protection design for aircraft should be qualified and compliance with airworthiness standards related to lightning protection must be substantiated in the process of certification. In this paper, I studied means of compliance for lightning protection through analysis of some test cases, including the KC-100 airplane that firstly obtained civil type certificate in Korea. Based on this paper, it will be also necessary to study on the effect of lightning for space launch vehicles.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.9
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• pp.94-99
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• 2011

This paper verified the characteristics of electrical continuity and mechanical strength of steelwork required to use it as a down-conductor in lightning protection system. It was proven that the steelwork in reinforced concrete apartment has an excellent electrical continuity with low resistance(less than 0.2[${\Omega}$].). But it was confirmed that a poor connection between two reinforcement bars can easily cause serious damages of the concrete even with the impulsive current of 50[kA], 10/350[${\mu}s$]. These results of experiments mean that the additional measures are necessary in using the steelwork as the down-conductor of the lightning protection system.

• Journal of the Microelectronics and Packaging Society
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• v.13 no.3 s.40
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• pp.27-32
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• 2006

The occurrence frequency of lightning and surge from the weather accident is increasing recently, which the damage scale have been enlarged every year. A protection system development to solve these problems have been risen to a multinational concern field. In this paper, a novel protection system is proposed to restrain lightning and various surges which happen in electricity and communication equipment. The proposed protection system is designed to the structure to restrain the rise of the earth potential which is become to the problem of conventional protection system. The secondary damage as a result does not happen. The practicality of the developed surge protection system is proved through various accident occurrence simulator.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.4
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• pp.130-140
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• 2017

Lightning protective design of an aircraft fuel system is closely related to the safety of the flight. Recently, composite material in building an aircraft becomes more important because it can reduce the weight of the aircraft. The composite materials decrease the protection against the effect of lightning. Lightning protective design of metal material aircraft has been researched for a long time and the design technique has been announced widely. However, research on the lightning protective design using composite material aircraft is very limited. In this study, lightning protective design for fuel tank structural component, access cover, fuel filler cap and drain valve in carbon fiber composite material aircraft have been presented. To show the compliance with FAA airworthiness standard regarding the presented protection designs, three steps, including lightning strike analysis, lightning environment analysis and certification test, were conducted in accordance with FAA AC 20-53.

• Journal of Electrical Engineering and Technology
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• v.13 no.2
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• pp.1021-1029
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• 2018

During the past few decades, the lightning protection angle (${\alpha}$) has been proposed through several technical matters, namely graphical technique, numerical data and mathematical equation respectively. Nevertheless, these techniques are very complicated, and are difficult to utilize because they also contain several constraints practically. Hence, this paper proposes a novel equation of the lightning protection angle, which is a simple correlation, concise and easy to be implemented. Furthermore, the reliable result of this equation can confirm accuracy through comparative analysis with all previous techniques. As a result, these solutions are altogether equivalent. This novel equation can analyze the lightning protection angle of the vertical air termination system installed at the vertex of the royal pagoda in a Khema-pirataram temple which is at high risk due to lightning flashes.

• Journal of the Korean Institute of Gas
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• v.24 no.4
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• pp.48-55
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• 2020

The installation of lightning protection system has recently been increasing, but the amount of damage has still been increasing. In this study, survey (interview) and field conditions were conducted to identify the installation and safety standards of the lightning protection system. it was analyzed that the safety management system is non-existent at the stage of the design, manufacturing and construction of the site lightning protection system, and that the safety inspection of the lightning protection facility is not properly managed. It has been shown that lightning protection systems, that can solve these problems, need to be re-established according to the reality so that safety inspection can be carried out in accordance with safety standards such as management of safety certification products, operation of survey institutions, design, manufacturing, and construction of safety standards at a national level.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.4
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• pp.8-14
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• 2002

A modern lightning protection system is required to eliminate the risks such as electrical shocks and damages of structures, electrical and electronic equipments due to lightning. However, the conventional lightning protection systems play and important role in protecting persons and structures only. Thus an effective lightning protection system is indispensable today in computer, information and communication facilities and etc. The mafor objective of this paper is to develop the technology to protect electronics and computerized facilities against lightning-caused overvoltages. The study is oriented on the control of the potential rise of down conductors with the type and installation method of down conductors. As a result, to reduce side flashes and hazards caused by the potential rise of down conductor due to lightning current, the coaxial cable with a low characteristic impedance and high insulation level is suitable for a down conductor. In particular it is extremely effective to bond down conductors to the steel supporter, metal raceways and steel frame of structures.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1637-1640
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• 2005

This paper presents a technique for electromagnetic field analysis on surge response due to Mid-span back-flashovers effects in lightning protection system of 500 kV EHV single circuit transmission tower by the neural networks method. These analyses are based on modeling lightning return stroke as well as on coupling the electromagnetic fields of the stroke channel to the line. The ground conductivity influences both the electric field as well as the coupling mechanism and hence the magnitude and wave shape of the induced voltage. The technique can be used to analyzed the corona voltage effect, the effective of stroke to the span tower, the surge impedance of transmission lines. The maximum voltage from flashovers effects in the lines. The model is compatible with general electromagnetic transients programs such as the ATP-EMTP. The simulation results show that this study analyses for time-domain with those produced by a cascade multi-section model, the surge impedance of a full-sized tower hit directly by a lightning stroke is discussed.