• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.779-783
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• 1992

In recent years, it is strongly required to supply high quality electrical power without insulation failure in distribution power cables. Therefore the exact measurement and judgment ar out deterioration degree of cables are essential to increase that supplying reliability. This paper will introduce various diagnostic methods of off-line and live-line cables also propose the judgement criteria and newly trend of diagnostic technique at present.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.658-660
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• 2005

본 논문에서는 한전 22.9kV 배전선로의 고장전류 및 선로손실 계산의 기초 자료로 활용하고 있는 배전선로 선종별 임피던스 값을 EMTP를 사용하여 계산하였다. EMTP와 그 보조 프로그램인 LINE CONSTANTS와 CABLE CONSTANTS의 간단한 계산 원리와 근거들을 각 항목들별로 자세히 기술하였다. 각 선종별로 기하학적 위치와 물리적은 제정수를 사용하여 계산을 하였으며, 가변 가능한 변수들은 모두 조정하여 상호 비교하였다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.9
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• pp.83-89
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• 2013

Power distribution system has been changed from radial system to closed loop or mesh system due to connection of distributed generation growth. Data from distribution equipments which are installed at distribution line is required to be accurate for the performance of DMS(Distribution Management System). This paper analyzes the voltage measurement data from distribution equipment. However, the results of the analysis are confirmed to have some errors in voltage measurement data from distribution equipment. These errors come from aging of voltage sensor in distribution equipment and inaccurate data transfer to FRTU(feeder remote terminal unit) through the controller. The main problem is that the voltage measurement data of distribution equipment can not be assessed after it's first installation at the distribution line. The voltage measurement accuracy assessment system is to assess the voltage measurement data from distribution equipment on hot-line. This study had a field test to verify the performance of system.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.9
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• pp.799-804
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• 2016

Broadband powerline communication (BPLC) uses distribution lines as a medium for achieving effective bidirectional data communication along with electric current flow. As the material characteristics of power lines are not good at the communication channel, the development of power line communication (PLC) systems for internet, voice, and data services requires measurement-based models of the transfer characteristics of the network suitable for performance analysis by simulation. In this paper, an analytic model describing a complex transfer function is presented to obtain the attenuation and path parameters for a multipath power line model. The calculated results demonstrated frequency-selective fading in multipath channels and signal attenuation with frequency, and were in good agreement with the experimental results. Inductive coupling units are used as couplers for coupling the signal to the power line to avoid physical connections to the distribution line. The inductance of the ferrite core, which depends on the frequency, determines the cut-off frequency of the inductive coupler. Coupling loss can be minimized by increasing the number of windings around the coupler. Coupling efficiency was improved by more than 6 dB with three windings compared to the results obtained with one winding.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.9
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• pp.108-117
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• 2010

The main contents of this paper are the PQM system construction case and distribution system harmonic voltage analysis. The PQM system has constructed by KEPCO in order to investigate power quality of distribution power system for new power quality standard of KEPCO. In result, we have confirmed that voltage harmonic measurement value of the high voltage contract customer 8 households is suitable the KEPCO harmonic standard tentative plan. And the voltage harmonic value of distribution line end side is not always more high than source side by harmonic current offset effect. In the future, acquired data by season, region, load from the PQMS will be used on the resonable harmonic standard enactment in KEPCO.

• Computers and Concrete
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• v.14 no.3
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• pp.263-277
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• 2014

This study investigated four electric field configurations of two-dimensional accelerate lithium migration technique (ALMT), including line-to-line, plane-to-line, contour-to-line and plane-to-plane, and analyzed the ion migration behavior and efficiency. It was found that the free ion distribution diagram and voltage distribution diagram were similar, and ions migrated in the power line direction. The electrode modules were used for the mortar specimen with w/c ratio of 0.5. The effectively processed areas accounted for 14.1%, 39.0%, 49.4% and 51.4% of total area respectively on Day 28. Larger electrode area was more advantageous to ion migration. In addition, it was proved that the two-dimensional electric field could be divided into different equifield line active regions, and regarded as affected by one-dimensional electric field, and the ion migration results in various equifield line active regions were predicted by using the duration analysis method based on the theoretical model of ion migration obtained from one-dimensional test.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.1
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• pp.38-42
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• 2004

In this paper we analyzed the electromagnetic behavior of a superconducting fault current limiter (SFCL) under the quench state using FEM. The analysis model used in this work is 5.5 KVA meander-line type SFCLs which are currently developed by Superconductor Power System Lab in Korea Electric Power Research Institute. Meshes of 3,650 triangular elements were used in the analysis of this SFCL. Analysis results showed that the distribution of current density was concentrated to inner curved line in meander-line type SFCL and the maximum current density was 14.61 A/$m^2$ and also the maximum Joule heat was 2,030 W/$m^2$ in this region. We think that the new and the modified structure must be considered for an uniform distribution of the electromagnetic field.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.432-436
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• 1991

This paper presents a new algorithm for the countermeasure to alleviate without shedding system loads the line overloads due to contingency in power system. This method for relieving by line switching is based on obtaining the line outage distribution factors - the linear sensitivity factors, which give the amount of change in the power flow of each line due to the removal of same other line in the power system. These factors are made up of the elements of Bus Reactance Matrix and branch reactances. In this paper a fast algorithm and program is presented for obtaining only the required Bus Reactance elements which corresponds to a non - zero elements of Bus Admittance Matrix and elements of columns which correspond to two terminal Buses of the overloaded(monitored) line. The proposed algorithm has been validated in tests on the 6 busbar test system

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.5123-5127
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• 2011

Research and development for the technology, that is about maintenance and accidents prevention of underground power distribution line, are demanding. The precise detection of leakage point of underground power line is very important, because it is difficult to detect the exact location of a fault in underground power line and to repair faults. When earth electric potential is measured to detect underground electric leakage point after transmitting AC electric pulse wave to underground power line, it must be measured in a specific half period of AC pulse wave because the distribution of the electric earth potential varies with the polarity of the transmitted wave. In this paper we proposed the measurement of half period modulated earth potential as a method to detect a underground leakage point. And We compared the proposed method with other methods. Through experiments we verified that the proposed method can be implemented and operated properly.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.4
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• pp.123-130
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• 2006

Airport facility is infrastructure that become external credit worthiness and linear measure of country competitive power. Among them, an airport electric power receiving and distribution facility is very important. In this paper, sorted domestic airline as 4 grades by code to accomplish standardization for airport electric power receiving and distribution facility. And established define and coverage about electric power receiving and distribution facility. And then analyze problem of existing airport and presents standardization. Finally, present standard single-line diagram by airport grade and system grade standard of airport electric power receiving and distribution facility