• 한국전기전자재료학회논문지
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• 제21권1호
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• pp.35-43
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• 2008

Aviation obstacle lights including controller for the safe night aviation service have applied to high voltage transmission line of which height is from $60{\sim}180 m$, Fresnel lens made by Augustine Fresnel have been applied to light houses, These Fresnel lens were applied to aviation obstacle lights and have been universally used, It was reported that Fresnel lens for aviation obstacle light was used in the first place in Korea in 1987, LEDs have recently been applied to aviation obstacle lights, So, the optimum physical design is essential to the design of aviation obstacle light. In this study, optical and three dimensional modeling of LED module and globe lens were performed, And thermal analysis due to LED thermal source and service thermal condition in high voltage transmission line was performed and was analyzed comparing with experiments, The optimum design process of medium intensity LED aviation obstacle lights was constructed with three dimensional modeling, thermal analysis, and thermal experimental technique.

• 한국전자파학회논문지
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• 제16권10호
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• pp.1036-1042
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• 2005

다중 전송선들로 회로를 구성할 경우 필요에 의해 중간 부분이 구부러진 형태를 갖기도 하는데, 이때의 누화는 금속으로 채워진 비아 홀 펜스를 전송선 사이에 위치시킴으로써 감소시킬 수 있다. 이러한 효과를 해석하기 위하여 비아 홀 펜스를 포함한 다중 전송선을 구간별로 나누고, 전송선 구간을 위한 회로 개념 접근법과 비아흘 구간을 위한 임피던스 모델링을 이용하고, 각 구간을 ABCD 행렬로 나타내어 직렬 연결하는 방법을 제안하였다. 마지막으로 이 방법에 의한 최종 계산 결과가 일부 저주파 대역을 제외하고 대략 3 dB 이내의 범위로 측정 결과와 일치함을 확인하였다.

• 전자공학회논문지A
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• 제33A권12호
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• pp.33-38
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• 1996

In this paper, we modeled the complex dielectric constant and analyzed the projpagation characteristics of a FR-4 composite substrate with different compositions. From the wideband dielectric modeling and the propagation loss analysis of FR-4 composites that consists of FR-4 resin and E-glass reinforcement,we have found that the propagation loss and velocity increase with the volume fraction of FR-4 resin above 1 GHz. These results are helpful in determining to deisgn optimum substrate composition ratio and cross-sectional geometry of high-speed and high-density transmission line.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.15-17
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• 2005

The protection of underground cables against transient overvoltages resulting from lightning and other causes is important in cable-line which is connected with overhead line and underground cable. This paper investigates the failure of SVL(Sheath Voltage Limiter) and presents the application of protection methods for single point bonding on underground transmission cable system. EMTP(Electromagnetic Transient Program) is used in order to study the overvoltages and modeling of components of the system such as, underground cables, SVLs and towers.

• 전기학회논문지P
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• 제54권4호
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• pp.163-170
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• 2005

This paper deals with an improved fault location algorithm with compensation ground capacitance through distributed parameter for a long parallel T/L. For the purpose of fault locating algorithm non-influenced by source impedance and fault resistance, the loop method was used in the system modeling analysis. This algorithm uses a positive and negative sequence of the fault current for high accuracy of fault locating calculation. Power system model of 160km and 300km long parallel T/L was simulated using EMTP software. To evaluate of the proposed algorithm, we used the several different cases 64 sampled data per cycle. The test results show that the proposed algorithm was minimized the error factor and speed of fault location estimation.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2002년도 종합학술발표회 논문집 Vol.12 No.1
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• pp.324-327
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• 2002

For the characterization of arbitrary shaped printed circuit board, lossy transmission line grid model based on SPICE netlist and analytical plane model based on the segmentation method are proposed in this paper. Two methods are compared with an arbitrary shaped power/ground plane. Furthermore, design considerations for the complete power distribution network structure are discussed to ensure the maximum value of the PDN impedance is low enough across the desired frequency range and to guide decoupling capacitor selection.

• 한국통신학회논문지
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• 제24권12A호
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• pp.1985-1991
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• 1999

본 논문은 HANbit ACE64 ATM 교환기 시스템의 데이터 경로인 IMI(Inter Module Path)에 사용되는 고속 전송선로인 Twinax 케이블을 two-port lumped Spice-network 모델로 구현하기 위해 lumped 네트워크 요소와 수학적 함수를 사용하여 개발하였다. 사용된 요소들은 저항성분과 주파수의존 전압제어 소스로 구성되어 있고 Hspice 수학적 함수인 FREQ, DELAY, POLY를 사용하여 구현하였다. 구현된 모델을 사용하여 케이블 길이와 종류에 따른 각종 노이즈 분석을 실시하여 그 특성을 비교 분석하였다.

• 대한전기학회논문지:전력기술부문A
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• 제50권9호
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• pp.411-416
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• 2001

Distance relay is the most widely used in transmission line protection because it is applicable not only as main protection but also as back-up protection. However, the protection range of the distance relay is always fixed in the unchangeable operating range while the power system varies, and therefore the distance relay is the device that is the highly influenced by the power system changes. In this regard, this paper describes an approach to minimize the mal-operation of the distance relay due to the power system changes through changing protection range of the distance relay into optimal condition in response to the load variation and power system condition. Also mal-function of the distance repay in case of high resistance ground faults could be minimized through modeling the protection range into quadratic function.

• 한국전자파학회논문지
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• 제9권6호
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• pp.802-812
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• 1998

고전압 발/ 변전소의 근무자나 송전선 작업자 및 주변거주자가 전계 노출에 안전해야 함은 중요한 일이다. 본 논문에서는 복잡하고 계산시간이 많이 소요되는 인체의 3차원 유도전류를 계산하기 위해 전압원(송전선 로)의 효과적인 모델링 기법을 사용하여 전압원과 피유도체를 분리하지 않고 직접 3차원 정전용량을 구함으 로써 불평등 전계하의 임의의 3차원 공간상에서도 인체에 미치는 유도전류 해석이 가능한 장접을 갖도록 하 였다. 사례연구로 본 연구에서 제안한 알고리즘을 765 kV급 초고압 송전선로에 적용하여 인체 유도 안전 성을 평가한 결과 765 kV 송전선에서 인체의 단락전류는 인체의 위치에 따라 0.3 mA에서 6.8 mA로 분포 되었다. 특히, 송전선로에서 활선 작업시 단락전류 $I_{sc}$의 크기는 ANSI 허용기준인 5 mA를 념을 수 있어 활 선 작업시 작업자의 전계의 방호 대책을 위해서는 도전물질로 구성된 보호복이 필요함을 알 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.239-241
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• 2000

This paper describes a modeling of a FACTS(Flexible AC Transmission System) device, namely, SSSC(Static Synchronous Series Compensator) model. The SSSC, a solid-state voltage source inverter coupled with a transformer, is connected in series with a transmission line. SSSC provides controllable compensating voltage, which is in quadrature with the line current, over an capacitive and an inductive range, independently of the magnitude of the line current. This SSSC model is obtained from the injection model for series connected VSC(Voltage Source Converter) by adding a constraint that the injected voltage should be in quadrature with the line current. The paper discusses the basic operating and performance characteristics of the SSSC, and power flow control in power system.