• Title/Summary/Keyword: lightning

Search Result 908, Processing Time 0.029 seconds

Considering the Multi-Purpose Display Designed for Aircraft Lightning Protection (낙뢰보호를 고려한 항공기용 다목적 디스플레이 설계)

  • Cheon, Young-Ho;Lee, Seoung-Pil;Park, Jun-Hyeon
    • Journal of Advanced Navigation Technology
    • /
    • v.18 no.5
    • /
    • pp.445-454
    • /
    • 2014
  • In this paper, we introduce measures designed content for RTCA DO-160 F, Section 22 tests performed to verify the effects of indirect lightning and testing process of the test was carried out in the multi-purpose display certification process. This is referred to as indirect effects of lightning capability of an aircraft having electrical electronic equipment failure or damage to bring lightning induced voltages. In order to protect the avionics from lightning indirect effects of these aircraft are analyzing the effects of lightning strikes on aircraft and aircraft systems and interior design needs protection against the threat on their part. In this paper, we introduce RTCA DO-160 F, component selection process according to Section 22 category selection method and the selected level for determining the level of such measures for protection against lightning of multipurpose display for this aircraft. It also introduces the actual test process to confirm that the designed effectiveness of the selected part. We expect a good example of the lightning planned for future development of measures designed avionics through each step of the process introduced this.

A Basic Study on the Attachment Process of Lightning Leader to Ground (낙뢰 리더의 대지부착과정에 대한 기초적 연구)

  • Yoo, Yang-Woo;Kim, Seung-Min;Kim, You-Ha;Lee, Bok-Hee
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.28 no.10
    • /
    • pp.82-88
    • /
    • 2014
  • This paper presents the results of model tests for the attachment process of lightning leader to ground which is one of poorly understood processes of cloud-to-ground lightning discharges. In order to simulate the attachment process of lightning leader to ground, we investigated the discharge characteristics of air gap between the tip of needle-shaped electrode and the soil surface as a parameter of moisture content in soils when the positive and negative $1.2/50{\mu}s$ lightning impulse voltages are applied. The breakdown voltage and the discharge light were observed. As a result, the attachment processes of lightning leader to ground are strongly dependent on the grain size and the moisture content of soils. The time to breakdown was shortened with increasing the magnitude of incident impulse voltages. The delay time from application of the highest voltage to breakdown in sand is shortened with increasing the moisture content. The delay time from application of the voltage to breakdown in gravel varied from about $0.5{\mu}s$ to several ${\mu}s$. As the moisture content in soil increases, the breakdown voltages are decreased and the breakdown voltage versus time to breakdown curves are shifted toward the lower side. The results obtained in this work are similar to those for non-uniform air gap stressed by lightning impulse voltages.

A Study on Means of Compliance for Lightning Protection in the System and Structure of Air Vehicles (비행체 시스템과 구조물의 낙뢰 보호 적합성 입증방법에 관한 고찰)

  • Jeong, Duckyoung
    • Journal of Aerospace System Engineering
    • /
    • v.14 no.spc
    • /
    • pp.49-55
    • /
    • 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.

A Study on the Effects of Lightning Arrestors Installment on a 154kV Transmission System (154kV 송전선로용 피뢰기 현장 설치 효과 분석)

  • Choi, Han-Yeol;Gu, Sung-Wan;Min, Byeong-Wook;Park, Soon-Kyu;Lee, Bong-Hee;Kwak, Joo-Sik
    • The Transactions of the Korean Institute of Electrical Engineers P
    • /
    • v.58 no.2
    • /
    • pp.184-189
    • /
    • 2009
  • Lightning has been identified as one of the leading causes of outages on transmission and distribution systems. As sensitive loads and reliance on electric power increase year by year, it is getting more focus on stable and high quality of power supply. To protect the transmission and distribution line from lightning, the transmission lightning arrester can be the effective facility on the power system. This paper discusses Gapped type Arresters application results by analysing effects of lightning arresters on transmission and distribution line.

The Construction of distribution test facilities of lightning protection equipment (배전급 내뢰설비 시설효과 분석 실증시험설비 구축에 관한 연구)

  • Kang, Moon-Ho
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
    • /
    • 2004.11a
    • /
    • pp.301-303
    • /
    • 2004
  • In distribution system about 5% of total outage is due to the lightning stroke. In order to reduce the rate of outage occurrence, distribution lightning protection equipments such as a secondary arrester, arching horn and various ground electrodes are developed and installed in the inside and outside of the county. Therefore it is needed to construct the test facilities to analyze the effect of these equipments. In this paper we describe the main content of the test facilities of lightning protection equipments. We have completed the field test of distribution lightning protection equipments for example lightning arrester, secondary arrester and arching horn etc.

  • PDF

Propagation Tendency of Lightning Surge in the Power and Communication System (전원 및 신호시스템에서의 뇌서지 전파양상)

  • Lee, Tae-Hyung;Cho, Sung-Chul;Eom, Ju-Hong
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
    • /
    • 2007.05a
    • /
    • pp.245-249
    • /
    • 2007
  • The tendency of lightning surge to propagate displays the difference for applicable power and equipment. However, looking into the subject equipment with the lightning surge, the lightning surge can be divided in between the two lines of power, between the power line and the ground, the power line and the PE conductor, between the neutral line and the ground and the like. In addition, in the event of the communication equipment, there exists the case of lightning surge entered from the power line in addition to the entry between the communication lines, the communication line and the ground. In this study, the tendency of propagation of lightning surge penetrated on to the subject equipment is analyzed through the empirical experiment in accordance with the ground method by using the independent ground, common ground, bypass arrester and others among the techniques for safety improvement in power lines.

  • PDF

A Study on the Design for Lightning Detection System of AOA methods for 3D Lightning Detection (낙뢰의 3차원 관측 위한 AOA 방식 낙뢰감지기 설계에 관한 연구)

  • Woo, J.W.;Kwak, J.S.;Moon, J.D.;Kawasaki, Zenichiro
    • The Transactions of the Korean Institute of Electrical Engineers C
    • /
    • v.55 no.11
    • /
    • pp.527-531
    • /
    • 2006
  • Since 1996, KEPCO has been operating a wide range lightning detection system, LPATS, and been accumulating relative application techniques and statistical analysis skills. So, KEPRI already has its own basis to develope more accurate advanced detection technology and references to do comparative study. For three-dimensional imaging of lightning channels, UHF/VHF antenna systems were installed at 2 sites. The distance between two sites is about 30 km. These systems were used the AOA(Angle of Arrival) methods for lightning detection. In this paper, we would like to introduce about our system and its results.

The Analysis Results of Lightning Overvoltages by EMTP for Lightning Protection Design of 500kV Substations

  • Ju Hyung-Jun;Lee Heung-Ho
    • KIEE International Transactions on Power Engineering
    • /
    • v.5A no.4
    • /
    • pp.366-370
    • /
    • 2005
  • To meet increasing power demand, 500 kV power systems are under consideration in the regions of some Middle Asian countries. As the power system voltage becomes higher, the cost for the power system insulation increases significantly. 500 kV transmission systems will become the basis of a region's power system and they require much higher system reliability. Consequently, by the methods of limiting overvoltages effectively, a reasonable insulation design and coordination must be accomplished. In particular, the Substations must be constructed to be of outdoor type. In order to determine the various factors for the insulation design, the EMTP (Electro-magnetic transient program) is used for the magnification of transient phenomena of the 500 kV systems in the planned network. In this paper, we will explain the calculation results of lightning overvoltages by the EMTP for lightning protection design for the 500 kV substations. To obtain reliable results, the multi-story tower model and EMTP/TACS model are introduced for the simulation of dynamic arc characteristics.

Analysis of the lightning characteristics by the LPATS in KOREA (낙뢰위치 표정시스템(LPATS)에 의한 2004넌 한반도 낙뢰통계 분석결과)

  • Kwak, J.S.;Woo, J.W.;Kweon, D.J.;Kang, Y.W.;Moon, J.D.
    • Proceedings of the KIEE Conference
    • /
    • 2005.07a
    • /
    • pp.606-608
    • /
    • 2005
  • As the overhead transmission lines are exposed to the outdoor weather, the causes of the transmission lines faults are from natural conditions, and among these faults, the outage rate due to lightning is more than 60%. The lightning causes the damage of power system equipments, the shut down of electricity and the electro-magnetic interference. Therefore, the pertinent insulation design is important, not only to decrease the damage of the facility itself but also to increase the reliability of electric power system. For these reasons, we have to obtain and accumulate the lightning current parameters for the basic lightning research. This paper describes the statistical distribution of lightning current parameters and the IKL map.

  • PDF

Transient State Analysis of Faults Caused by Lightning Surge in Distribution Line (뇌서지에 의한 배전선로 고장 시 과도상태 분석)

  • Lim, Sung-Yong;Kim, Kyu-Ho
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.65 no.1
    • /
    • pp.51-57
    • /
    • 2016
  • This paper presents the voltage characteristics of the various faults after lightning surge hits the overhead grounding wire close to the transformer's secondary side. Based on the modeled distribution system, the cases of the various faults occurred by lightning surge are simulated using EMTP/ATPDraw and maximum overvoltage and RMS voltage according to the distances from the transformer are investigated. As a result, it is seen that the voltage characteristics of faults caused by lightning surge is different depending on the fault type and the voltage characteristics can be used to detect the fault type caused by lightning surge.