• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.6
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• pp.702-707
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• 2018

In case of Lighting occurs in Domestic combined distribution line, normally the voltage for the neutral line increase dramatically. General connection for underground cable is bundled common earth type so the lightning over voltage increase at the concentric-neutral line is not big enough to give impact on cable sheath. But in case of Non bundled common earth type it is necessary to analyze the phenomena on cable sheath caused by lightening overvoltage. Especially pole and cable joint are the core factor to consider. In this paper concrete pole and cable joint were evaluated in case of Non bundled common earth type combined distribution Line. EMTP simulation model has been designed and several case study were made. Also several experimental test were made to verify the simulation result.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.78-81
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• 2006

In this paper, the investigation of characteristic impedance on low voltage distribution system is described The residential area of LV distribution systems is researched for the modeling. At frequency range from 1MHz to 30Mhz, the input characteristic impedances of low-voltage distribution network are obtained with experiments. The low-voltage distribution system based on the model is built at the laboratory building. S parameters are measured by performing experiments. Finally, the characteristic impedances are reported.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.809-811
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• 1993

The load impedance of power lines generally varies with time, areas, and season. Also, the harmonic noises by the power electrical equipments are scattered through the power lines. The received signal level varies with the environment and is not able to detect the PLC(Power Line Carrier) signal. For this reason, it is requried for the signal transmitter to hold the received signal level uniform independently with the variation of the load impedence. In this paper, the power lines are modeled simply and a method keeping the received signal level uniform is suggested through the analysis of the signal transmission characteritics of the PLC coupler using tank circuit.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.33-35
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• 1994

This Paper Presents a practical approach to evaluate the reliability indices of electric distribution systems. The use of reliability evaluation is placed with the framework of distribution system planning. In this paper, the reliability model is based on an analytical method, connecting component failure to load point outage each section. five case studies are reported in the paper. These are to study the effect of varying failure rates and repair times on distribution feeders. The results of a study on sample system are presented in this paper.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.319-322
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• 1999

In order to accurately measure the high voltage of 22.9[kV] power distribution lines, we investigated the temperature dependence of measuring voltage for single element and stack elements(22, 44, 66 layers, respectively). When one line voltage is 13, 20O[V], the error of measuring voltage with temperature(-25[$^{\circ}C$]~50[$^{\circ}C$]) was decreased with increasing of stack number and stack element with 66 layers was the least error of ${\pm}0.87%$.

• Proceedings of the KIEE Conference
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• summer
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• pp.257-259
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• 2004

This paper proposes the identification method for the faulted feeder, where it identify whether the faulted feeder is the DG-connected feeder or the neighboring feeder (but sharing the same bus of the substation). In general, DG has to be disconnected from the grid when the fault occurs on the interconnected distribution feeder as soon as possible. However, the faults occured on the neghboring feeder would mistakenly cause the disconnection of the DG. For reliable operation of DG, DG should be sustained at the fault occurred on neighboring distribution feeders. The proposed identification method utilizes the impedance monitored from the DG and examines the coordination of overcurrent relay of the distribution system. This paper describes how the proposed method to identify the faulted feeder and how the method can be utilized.

• Annual Conference of KIPS
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• 2010.04a
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• pp.619-622
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• 2010

무선센서네트워크는 한정된 에너지 자원을 장기간 사용하기 위하여 주로 에너지 절약을 위한 연구에 중점을 두게 됨으로써 상대적으로 지연시간에 대한 고려는 멀어지게 되었다. 그러나 송배전 선로 등과 같이 일렬로 진행하는 설비 감시에 관한 무선센서네트워크를 구축할 경우에는 일정 구간 단위로 클러스터 헤드의 중계가 반드시 거치게 되므로 클러스터링 자체가 어렵거나 지나치게 많은 전송지연을 유발하며, 한개 노드 장애시 전체 노드에 영향을 주게 되었다. 이를 개선하기 위하여 본 논문에서는 일렬로 진행하는 소규모 클러스터의 효과적 클러스터링 방법과 Every Other Hop(EOH) 중계전송 기법을 사용하여 전송지연시간을 줄이고, Single Point of Failure 문제 해결을 가능하게 하였다.

• Annual Conference of KIPS
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• 2010.11a
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• pp.1316-1319
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• 2010

스마트 홈은 유무선 통신 인프라를 기반으로 댁내 다양한 기기 간 통신을 가능하게 함으로써 사용자에게 원격 에너지 관리, 방범, 의료 등 자동화된 지능형 서비스를 제공할 것으로 기대되고 있다. 이는 기존 전력망에 IT 기술을 융합하여 효율적인 전력 에너지의 송 배전 및 실시간 정보 서비스를 제공하는 스마트 그리드 기술을 기반으로 하고 있으며, 사용자 실생활과 밀접한 관계를 가지기 때문에 보안 문제 발생 시 치명적인 피해를 입힐 수 있다는 특징을 가진다. 이에 본 논문에서는 스마트 홈 및 스마트그리드에 대한 분석을 통해 안전한 스마트 홈을 위한 스마트그리드 보호 방안을 도출한다.

• Proceedings of the KIPE Conference
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• 2020.08a
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• pp.457-458
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• 2020

본 논문은 저전압 직류배전 (LVDC)이 도입된 공장 및 물류센터 등 에서 다수의 전동 지게차를 운용할 때, 효과적으로 충전할 수 있는 지게차 배터리 충전기를 제안하였다. 제안하는 충전기는 SiC 반도체 및 의도적으로 비대칭으로 설계한 공진 인덕터를 사용한 두 개의 위상천이 풀브릿지 컨버터로 구성된다. 이를 통하여 최대 200A급 고속 충전 및 다종의 배터리 규격 (48V, 80V) 대응과 함께 고효율, 고전력밀도를 달성 하였다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.6
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• pp.43-50
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• 2000

Design and experiments of a nondestructive testing system with a solenoid eddy current sensor to inspect deterioration of ASCR-OC (ACSR Outdoor Cross-linked Polyethylene Insulated Wires) usually used in HV overhead distribution lines in domestic areas in presented in this paper. Through corrosion mechanisms and deterioration results for ACSR-OC conductors are examined, it is shown that corrosion may lead to the reduction of the effective cross section area of conductors is proposed. The measurement system consisting of a constant current source with a RF frequency, a signal processing unit and a motor driver/ controller is designed and implemented. This instrument has such capabilities as detecting the sensor output and estimating diameter change of the testing conductors, continuously. As a result, it was verified that such corrosion detector system with an eddy current sensor can be shown good effectiveness for estimating the serious faults due to deterioration in overhead distribution lines and giving an early warming before severe aged conductor may lead to fail.