• 제목/요약/키워드: Protection Termination

검색결과 30건 처리시간 0.02초

뇌보호 설비를 위한 접지임피던스 측정기 개발 (Development of Ground Impedance Measuring Instrument for Lightning Protection System)

  • 이태형;조성철;엄주홍
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2006년도 추계학술대회 논문집 전기물성,응용부문
    • /
    • pp.194-195
    • /
    • 2006
  • This study evaluated the impedance characteristics of earth termination system and developed a variable frequency-typed inverter (measuring tool) for the utilization in ground design for lightning protection. The variable-frequency-typed inverter were composed of rectification part, voltage adjuster, IGBT controller and measuring part. Meanwhile, the square wave signal of variable frequency converted its frequency up to lightning surge band by using an IGBT after rectifying an alternating current (AC). It conducted performance evaluation of ground impedance of actual earth termination system by using the developed measuring tool for ground impedance and confirmed that such impedance-oriented performance evaluation was effective in the design of lightning protection.

  • PDF

공동주택 금속기와지붕 수뢰시스템의 자재 및 시공기법 개발 (Development of Components and Installation Techniques of Air-termination System on the Metal Roof in Apartments)

  • 이기홍
    • 조명전기설비학회논문지
    • /
    • 제25권10호
    • /
    • pp.109-115
    • /
    • 2011
  • Apartments covered with a metal roof made from galvalume steel are prevailing due to their economic and technical advantages. The metal roof, however, has disadvantages in terms of the installation of air-termination system on it because of the slip thickness of the metal roof. In this paper, the impacts of the lightning current to a metal roof were verified experimentally with a short lightning impulse current (10/350[${\mu}s$]). Also, we developed various supporters of air-termination conductor for the metal roof and verified their excellent workability and economical strength through field application test.

C/H 철탑 종단접속함 보호용 피뢰기 리드선 길이에 따른 뇌과전압 분석 (Analysis on Lightning Overvoltage According to Lead Length of Surge Arrester for Underground Cable Outdoor Termination Protection at C/H Tower)

  • 정채균;강지원
    • 전기학회논문지
    • /
    • 제65권2호
    • /
    • pp.257-263
    • /
    • 2016
  • This paper describes the lightning arrester transients in cable head termination. The installation references of cable head tower and lightning arresters are firstly reviewed, then the performance of lightning arrester operation is also evaluated based on lightning overvoltage analysis by the change of grounding lead cable length. This paper finally proposes the optimal length of grounding lead cable at the cable head termination. The limited lightning current is also proposed according to the change of grounding lead cable length. The results will contribute to protecting insulation breakdown failure against lightning surge at the terminations and joints.

공동주택에서의 인하도선시스템과 접지시스템 설계에 대한 고찰 (Considerations in Down-conductor System and Earth-termination System Design of Apartments)

  • 이기홍;이재복;장석훈
    • 한국조명전기설비학회:학술대회논문집
    • /
    • 한국조명전기설비학회 2006년도 춘계학술대회 논문집
    • /
    • pp.54-58
    • /
    • 2006
  • 본 논문에서는 공동주택에 적합한 인하도선시스템과 접지시스템 설계를 위한 기본적 사항에 대하여 고찰하였다. 공동주택의 철근구조체는 전기적 연속성을 갖지만 철근들끼리의 결속선에 의한 접속은 전자기계력에 대한 내력이 부족하다. 따라서 전용의 인하도선을 설치하고 이들을 건물 양 측벽의 철근구조체와 본딩하여 낙뢰전류가 인하도선 및 철근구조체에 분산되어 흐르게 하는 인하도선시스템을 제시하였다. 한편 공동주택의 접지시스템은 건물기초접지극과 피뢰설비를 위한 환형 접지극으로 각각 구성하고 이들을 서로 본딩하는 접지시스템을 제시하였다. 또한 공동주택 각동의 건물기초접지극을 공동구의 철근구조체나 접지선을 이용하여 서로 연결함으로서 공동주택 단지에 거대한 총괄접지시스템을 구현하는 방안을 제시하였다. 하지만 이러한 피뢰시스템을 구축하기 위해서는 완벽한 본딩시스템의 구축이 전제되어야 한다.

  • PDF

평가시공불량을 모의한 배전급 케이블 종단부의 전기적 사고 연구 (A Study on Electrical Accident of Distributing Cable Termination with Simulated Badness Construction)

  • 최재형;최진욱;김상현;김영석;김선구;백승명
    • 한국화재소방학회:학술대회논문집
    • /
    • 한국화재소방학회 2008년도 추계학술논문발표회 논문집
    • /
    • pp.465-470
    • /
    • 2008
  • This paper introduces experimental investigates of an electrical accident of the distributing cable termination with simulated badness construction. We prepared two termination kites, one is built-up type, the other is heat contraction type. Also, we manufactured cable termination that have simulated defect by badness construction and measured their insulation characteristics such as ac (35kV, 1min) and impulse (95kV, $1.2{\times}50{\mu}s$) withstand test. The influence of defects such as thickness and the gap between stress-con of housing and semi-conductor on insulating properties of the termination have been studied. The thickness decrease of insulator decreases ac breakdown strength. Dielectric breakdown traces of insulator that is damaged by knife displayed other shape. The gap of between housing and semiconductor deteriorates dielectric strength of insulator seriously.

  • PDF

A Novel Approved Mathematical Equation for Lightning Protection Angle

  • Singhasathein, Arnon;Rungseevijitprapa, Weerapun;Pruksanubal, Aphibal
    • Journal of Electrical Engineering and Technology
    • /
    • 제13권2호
    • /
    • pp.1021-1029
    • /
    • 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.

OBS 네트워크의 OAM 기본 체제 (A Framework for OAM in OBS Networks)

  • 신종덕
    • 한국통신학회논문지
    • /
    • 제29권1B호
    • /
    • pp.41-51
    • /
    • 2004
  • OBS (Optical Burst Switching) 네트워크에 관한 연구가 최근 활발히 진행되고 있으나 OBS 네트워크 운용에 필수적인 OAM (Operation md Maintenance)에 대한 연구는 아직 다루어지고 있지 않다. 본 논문에서는 다섯가지 OBS 기능들, 즉 BT (Burst Termination), BTX (Burst Transmission), BSW (Burst Switching), RSC(Routing and Switching Control), 그리고 PAR (Protection and Restoration)을 정의하였고, 이 기능적 모델에 근거하여 네트워크 운용 요구 조건들을 만족시키기 위한 OAM 아키텍처를 설계하였다. 또한, OAM 수행에 필요한 OAM 동작들의 정의와 OAM이 가능한 ingress 에지, 코어, egress 에지 노드들의 구조, 그리고 OAM 정보 및 통신 모델과 프로토콜 등과 같은 OAM 구현을 위한 기본 체제를 제안하였다. 그리고, 제안된 OAM 아키텍처를 이용하여 OBS 네트워크에서 발생 가능한 여러 가지 장애들에 대한 OAM을 정리하였다.

Linear Unequal Error Protection Codes based on Terminated Convolutional Codes

  • Bredtmann, Oliver;Czylwik, Andreas
    • Journal of Communications and Networks
    • /
    • 제17권1호
    • /
    • pp.12-20
    • /
    • 2015
  • Convolutional codes which are terminated by direct truncation (DT) and zero tail termination provide unequal error protection. When DT terminated convolutional codes are used to encode short messages, they have interesting error protection properties. Such codes match the significance of the output bits of common quantizers and therefore lead to a low mean square error (MSE) when they are used to encode quantizer outputs which are transmitted via a noisy digital communication system. A code construction method that allows adapting the code to the channel is introduced, which is based on time-varying convolutional codes. We can show by simulations that DT terminated convolutional codes lead to a lower MSE than standard block codes for all channel conditions. Furthermore, we develop an MSE approximation which is based on an upper bound on the error probability per information bit. By means of this MSE approximation, we compare the convolutional codes to linear unequal error protection code construction methods from the literature for code dimensions which are relevant in analog to digital conversion systems. In numerous situations, the DT terminated convolutional codes have the lowest MSE among all codes.

PL법 환경을 고려한 배전 케이블 종단부의 사고 유형 연구 (A Study on Accident Pattern of Distributing Cable Termination Considering PL Law Environment)

  • 백승명;최재형;최진욱;김영석;김선구;김상현
    • 한국조명전기설비학회:학술대회논문집
    • /
    • 한국조명전기설비학회 2008년도 추계학술대회 논문집
    • /
    • pp.319-322
    • /
    • 2008
  • This paper introduces experimental investigates of an accident pattern for the distributing XLPE cable terminations considering PL law environment. The influence of defects such as thickness and length decrease of XLPE, the impurity on XLPE and the gap between stress-con of housing and semi-conductor on insulating properties of the termination have been studied. The thickness and length decrease of XLPE decrease ac breakdown strengths. Dielectric breakdown traces of XLPE that is damaged by knife displayed other shape. The gap of between housing and semiconductor deteriorates dielectric strength of XLPE seriously.

  • PDF

국내 보호종료아동 보건복지 지원실태 분석 -천안시 사례를 중심으로- (Analysis of Health and Welfare Support for Children Who Have Ended Protection in Korea - Focused on the case of Cheonan city -)

  • 유태규
    • 문화기술의 융합
    • /
    • 제8권1호
    • /
    • pp.115-119
    • /
    • 2022
  • 「아동복지법 제16조 1항」에 의거 아동의 연령이 만18세가 되면 퇴소조치 되는 등 전국적으로는 매년 보호종료아동이 2,500명 가량 발생하고 있다. 하지만 중앙정부와 지자체의 효율적인 지원태세를 갖추기 위해서는 보호종료아동에 관한 명확한 실태조사가 필요한 바, 금번 연구에서 천안시에 거주 중인 보호종료아동의 주거, 건강, 교육, 취업, 사회적 관계 등 가장 기초적인 조사를 실시하였다. 결과적으로 전국 보호종료아동 대비 천안시 거주 보호종료아동의 주거와 사회적 관계는 양호한 것으로 나타났으나 정신과 질환비율이 높거나 취업, 창업비율이 상대적으로 낮게 나타나 이에 대한 관계기관과의 면밀한 협력체계 구축이 시급한 것으로 나타났다.