• Journal of Electrical Engineering and Technology
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• v.11 no.3
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• pp.602-608
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• 2016

Because of the random characteristics of lightning, the Monte Carlo method is applied to estimate the flashover rate due to lightning, however, the simulations using previous methods are difficult to both beginner and expert in power corporations. Therefore, this paper proposes the new and easy method to simulate the flashover rate by connection of electromagnetic transients program (EMTP) and MATLAB. The magnitude of a lightning strike is based on a curve measured in the field, while the classification of direct and indirect lightning depends on the striking distance. In a Korean distribution system, the flashover rate induced by lightning is simulated using proposed method. Simulations of the footing resistance according to the existence of an overhead ground wire (OHGW) are performed and the simulation results are discussed. The simulation results are compared with findings obtained with the IEEE Flash 2.0 program.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.438-439
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• 2008

KEPCO has been operating a lightning detection network, KLDNet, to cope with lightning-induced faults. An weather observation for last 40 years shows that heavy rainy days per year and the strength of rain have almost doubled. It could be interpreted as more frequent occurrence of lightning events. In accordance with that, the lightning activities and the mischievous influences, such as transmission faults, have increased. In this paper, the observed data by the network in 2007 is analyzed and compared with ten-years-old-statistics accumulated by the former system, LPATS.

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.1
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• pp.1-7
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• 2005

This paper describes the lightning surge analysis model of extra high voltage GIS using EMTP. Various lightning current parameters were investigated in order to confirm the impact on the lightning surge analysis such as lightning current amplitude, waveform, size of GIS, tower footing resistance and surge arresters. The multi-story tower model and EMTP/TACS model were introduced for the simulation of dynamic arc characteristics. The margin between the maximum overvoltage and BIL of the GIS was about 10 percent and the margin between the maximum overvoltage and BIL of the transformer was 21 percent.

• Proceedings of the KIEE Conference
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• 2002.11b
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• pp.355-357
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• 2002

Distribution lines are spanned on a much large area as compared to transmission lines, and therefore, are more often susceptible to lightning strokes. The selection of the proper value of basic insulation level(BIL), for particular insolation components of distribution structures in specific, is very important. Lightning strikes has current risetimes ranging from 0.1 to several $\mu s$ and can produce transient overvoltages substantially greater than the BIL of many distribution systems in spite of lightning arresters. This paper describes lightning overvoltage of a 22.9kV distribution system due to lightning strike. This study will provide the information on insulation coordination studies to adopt BIL.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1772-1774
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• 2002

Because the overhead transmission lines are exposed to the outdoor weather, the faults of the transmission lines are due to natural conditions, and among these faults, the outage rate by lightning is about 50%. The lightning causes the damage of power system equipments, the shut down of electricity and the electro-magnetic interference. To study the basic research of the lightning parameters for power system operation, LPATS-III (Lightning Positioning and Tracking System) has been introduced since 1995 in Korea. This paper describes the inspection result about location information error and the statistical distribution of lightning current.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.12
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• pp.555-560
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• 2006

As it has been reported that more than 60% of transmission line faults occurs due to lightning strokes, lighting is one of concerned issues in electric power utility company. Most of transmission line is double circuit in Korea. Double circuit outages account for 33.7 percent of total lightning faults from 1996 to 2004. Even though transmission fault might be cleared shortly by protective system, it could deteriorate the power quality accompanied with sag or flicker. Moreover, double circuit fault may lead to more aggravated situation, for instance, blackout. To Protect transmission lines from lightning stroke, reduction of tower footing resistance, multiple ground wires and unbalanced insulation in double circuit lines have been adopted. In this paper, we would like to introduce insulation design standards for lightning protection of Korea Electric Power Corporation.

• KIEE International Transactions on Electrophysics and Applications
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• v.3C no.4
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• pp.117-122
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• 2003

The AC power lines and signal lines of info-communication networks are routed on overhead poles and are highly exposed to lightning strikes. Due to the potential difference between grounding points of AC power lines and signal lines, the electronic equipments connected to the signal lines can easily be damaged by lightning surges. In this work, in order to develop reliable methods of protecting information and communication facilities from lightning surges, the reliability and performance of SPDs (surge protective devices) were experimentally investigated in an actual-sized test circuit. The behaviors of SPDs against lightning surges from AC power lines and signal lines and the coordinated effects of SPD installation methods were evaluated. As a consequence, it was confirmed that the bypass arrester methods and common grounding system are both highly effective.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2073-2075
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• 1999

To study the basic research of the lightning parameter for power system operation. LPATS(Lightning Position and Tracking System) has been introduced since 1995 in KEPCO. We have developed the lightning parameter analysis program. We obtained the various statistical distribution of lightning current parameters from 1995 by this program. In this paper, we describe the results on the comparison/analysis between the fault of transmission line and the LPATS lightning data.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1656-1658
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• 1998

This paper deals with a measurement system of a distance between lightning strokes and observatory station and spectrum analysis of electric fields radiated from lightning discharges. The distance measurement system, which consists of a loop type magnetic field sensor, a microphone and one chip microprocessor, is connected to a personal computer through RS232 port to acquire and process the data. This system is to use a difference of propagation velocity between an electromagnetic wave and a sonic wave produced by lightning discharge. Also, an electric field waveform and a frequency spectrum were investigated by an electric field measurement system with a hemisphere antenna and a spectrum analyzer with a biconical antenna and a log-periodic antenna, respectively. The results would be used as a basic reference to protect the power systems and electric circuits from lightning overvoltages.

• 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.