• Title/Summary/Keyword: Lightning strikes

Search Result 54, Processing Time 0.022 seconds

Statistics of Casualties and Damage Caused by Lightning Strikes in Korea from 2000 to 2007

  • Kim, Dong-Seong;Lee, Bok-Hee;Jeon, Duk-Kyu
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.23 no.7
    • /
    • pp.14-19
    • /
    • 2009
  • This paper presents statistics on lightning-caused damage to humans, structures, and electrical and electronic equipment. To reduce the number and amount of casualties and damage caused by lightning strikes, the statistical analysis of lightning-related damage reports is important in establishing lightning protection measures. The statistics of lightning death, injury and damage in Korea from 2000 to 2007 were primarily derived from mass media As a result, the annual average of lightning-caused deaths in Korea is about 5. Most lightning casualties involve people who work outdoors such as farmers and recreationists. Data on lightning-caused injuries to humans and damage to structures in this paper may be underestimated since the available data from mass media are incomplete. The actual lightning-caused casualties and damage in Korea may be greater than those presented in this paper.

A Study on the Characteristics of Lightning Detection over the Naro Space Center (나로우주센터 상공의 낙뢰 발생 특성 연구)

  • Kim, Hong-Il;Choi, Eun-Ho;Suh, Sung-Ho;Seo, Seong-Gyu
    • Journal of Environmental Science International
    • /
    • v.31 no.7
    • /
    • pp.543-553
    • /
    • 2022
  • The latest aerospace technology is important for the stable flight of a launch vehicle, but weather conditions on the day of launch are also one of the essential factors for successful launch campaign. If a launch vehicle is directly struck while preparing to take off from the launch pad on the day of launch or the electronic device are damaged by induced current during flight of the launch vehicle, this means launch failure and can lead to enormous national loss. Therefore, for a successful launch campaign, it is necessary to analyze the lightning detection characteristics of the Naro Space Center. In this study, the seasonal factors of the lightning that occurred over the Naro Space Center from 2003 to 2017, the influence of the polarity, and the correlation with the lightning intensity was confirmed. As a result, there was a high probability of intensive occurrence of multiple lightning strikes in summer, and a high proportion of positive (+) lightning strikes in winter. Lastly, in the distribution of the number of lightning strikes, an average of 2.0 to 2.5 negative (-) lightning strikes occurs in the coastal regions of the South and West Seas when one flash happens.

Safety Analysis for Passengers of Composite Car-body against Lightning Strikes (복합차체의 낙뢰에 대한 인체 안전성 분석)

  • Kill, Gyung-Suk;Park, Dae-Won;Kim, Sung-Wook;Park, Chan-Yong;Cho, Young-Jin
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.22 no.6
    • /
    • pp.526-531
    • /
    • 2009
  • In this paper, the safety for passengers of composite car-body against lightning strikes was analyzed by the application of an impulse generator which can produce impulse current up to 50 kA with 8/$20{\mu}s$ waveform. Potential difference on inside surface of the car-body was measured as a safety parameter for the passengers against lightning strikes. The potential difference between 20 em distant was 175 V at 37.67 kA, and it corresponds to 875 V between 1 m distant. The amount of charge flowing a passenger at 100 kA impulse current can be estimated to $0.31\;mA{\cdot}s$. This is much less than the limit amount of charge for human body, $30\;mA{\cdot}s$ which is presented by Koeppen and Osypka.

Acoustic Emission Monitoring of Lightning-Damaged CFRP Laminates during Compression-after-Impact Test

  • Shin, Jae-Ha;Kwon, Oh-Yang
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.32 no.3
    • /
    • pp.269-275
    • /
    • 2012
  • Carbon-fiber reinforced plastic(CFRP) laminates made of nano-particle-coated carbon fibers and damaged by a simulated lightning strike were tested under compression-after-impact(CAI) mode, during which the damage progress due to compressive loading has been monitored by acoustic emission(AE). The impact damage was induced not by mechanical loading but by a simulated lightning strike. Conductive nano-particles were coated directly on the fibers, from which CFRP coupons were made. The coupon were subjected to the strikes with a high voltage/current impulse of 10~40 kA within a few ${\mu}s$. The effects of nano-particle coating and the degree of damage induced by the simulated lightning strikes on AE activities were examined, and the relationship between the compressive residual strength and AE behavior has been evaluated in terms of AE event counts and the onset of AE activity with the compressive loading. The degree of impact damage was also measured in terms of damage area by using ultrasonic C-scan images. The assessment during the CAI tests of damaged CFRP showed that AE monitoring appeared to be useful to differentiate the degree of damage hence the mechanical integrity of composite structures damaged by lightning strikes.

A Study on the Risk of Lightning in Special Structures and its Verification Method (특수 구조물의 낙뢰 위험도와 검증 방안에 관한 연구)

  • Yoo, Jeong Hyun;Kim, Hei Sik
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.19 no.6
    • /
    • pp.664-668
    • /
    • 2018
  • Free-standing structures that are especially high are more likely to receive brain attacks caused by lightning. Since special structures are generally part of national industrial structures, lightning strikes mostly cause socio-economic damage. Lightning protection facilities are installed to prevent such lightning damage, but in 2015, support cables on West Sea bridges were hit by lightning, causing a lot of economic damage. Accordingly, the design of a lightning protection system shall establish protective measures after analyzing the risk of debris falling onto the structure. In this thesis, lightning strikes are analyzed directly in relation to the modeling system that operates the actual information collection system for lightning strikes, depending on the location of the tall, free-standing structures, and practical lightning hazard information is provided by a meteorological station. In addition, we propose monitoring and applying a probability correction rate to the calculation of the lightning risk based on the number of lightning strikes directly reaching the ground in order to obtain an effective lightning risk assessment.

Development of Wireless lightning detecting and warning system (무선식 낙뢰통보시스템 개발)

  • Kim, Kyung-Man;Kwon, Tae-Woon;Sim, Kwang-Yeol;Kim, Se-Yeol
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
    • /
    • 2006.05a
    • /
    • pp.500-503
    • /
    • 2006
  • This paper gives a Wireless lightning detecting and warning system. This system composed of transmitter and receiver. It promptly senses lightning strikes on the power lines and transmission towers by using the lightning current detection circuit in a small transmitter situated on the top of power tower, and it sends the number of lightning strikes and the ID. of the tower to patrols through the receivers. This system will be used to discover the exact location of a lightning strike.

  • PDF

Safety Analysis for Passengers of Composite Car-body against Lightning Strikes (복합차체의 낙뢰에 대한 인체 안전성 분석)

  • Kim, Sung-Wook;Choi, Su-Yeon;Park, Dae-Won;Kil, Gyung-Suk
    • Proceedings of the KSR Conference
    • /
    • 2008.11b
    • /
    • pp.144-150
    • /
    • 2008
  • In this paper, the safety for passengers of composite car-body against lightning strikes was analyzed by the application of an impulse generator which can produce impulse current up to 50 [kA] with 8/20 [us] waveform. Potential difference on inside surface of the car-body was measured as a safety parameter for the passengers against lightning strikes. The potential difference between 20 [cm] distant was 175 [V] at 37.67 [kA], and it corresponded to 875 [V] between 1 [m] distant. The amount of charge flowing a passenger at 100 [kA] impulse current can be estimated to 0.31 [mA s]. This is much less than the limit amount of charge for human body, 30 [mA s] which is presented by Koeppen and Osypka.

  • PDF

Analysis on Induced Surge Voltage of Electric Car Line affected by Lightning in Rapid-Transit Railway System (고속철도시스템에서 낙뢰로 인해 전차선에 유도되는 서지전압의 해석)

  • Lee, Sung-Gyen;Lee, Kun-A;Ko, Kwang-Cheol
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.29 no.5
    • /
    • pp.65-70
    • /
    • 2015
  • Lightning is one of hazards affecting the rapid-transit railway system. There are two effects, which are direct lightning surge to electric car line and induced lightning surge. Protection methods for the direct lightning surge are studied with various occasions, however, study of induced lightning surge is insufficient in spite of a large or small effects. In this paper, it is analysed the way that serge voltage is induced to electric car line by lightning strikes. By modeling the propagation process and the coupling phenomenon of electromagnetic wave produced by lightning strikes, it is achieved to make integrative circuit model combined with existing electric car model. The study is conducted into three different waveform of electromagnetic wave produced by lightning; rectangular wave, double exponential distribution wave, triangle wave. It is also simulated that the inducing serge is coupled to electric car line in an arbitrary location. The simulation results in that, when rapidly changing rectangular wave is supplied, maximum power is induced to electric car line.

A Study on the Analysis of Lightning Damage Impact in Domestic Offshore Wind Farm (국내 해상풍력발전단지 낙뢰피해 영향 분석에 관한 연구)

  • Seo, Jin-Gyu;Kim, Kyu-Ho
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.65 no.2
    • /
    • pp.247-252
    • /
    • 2016
  • The latest offshore wind turbines are easily exposed to lightning strikes because they are designed with longer blades and taller height to satisfy the growing capacity demands. The generation facilities and elements of the offshore wind farm are more vulnerable to lightning damage because of more severe, unpredictable weather conditions. Therefore, this paper presents the analysis of measure for lightning overvoltage mitigation in offshore wind farm planned in South Korea southwest seashore. The sensitivity analysis includes the steady state and transient state characteristics of offshore wind farm and proposes the countermeasure for mitigation of transient overvoltage by considering earth resistivity of the offshore environment.

Safety Analysis of Carbon Composite-body Against Lightning Strikes (탄소섬유 복합차체의 낙뢰에 대한 안전성 분석)

  • Kim, Sung-Wook;Park, Dae-Won;Kil, Gyung-Suk;Mok, Jae-Kyun;Han, Ju-Seop
    • Proceedings of the KSR Conference
    • /
    • 2008.06a
    • /
    • pp.321-326
    • /
    • 2008
  • Light weight of vehicles by composite materials makes possible high speed, energy saving, and low repair cost. As Bimodal Tram and Tilting Train eXpress(TTX) use carbon composite material for their bodies, safety for passengers and electrical devices against unexpected failures has been issued more than ever. Lightning strike which generates high voltages and large currents is the worst case for the safety of passengers and devices. With this background, we experimentally investigated the insulation breakdown phenomena on carbon composite materials by the application of lightning surge voltage and current. From the experimental results, we could estimate whether the composite body is safe or not for the inside passengers and devices against lightning strikes.

  • PDF