• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 춘계학술대회 논문집
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• pp.409-414
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• 2003

In this study we examined the method to select the size of the conductor rail for light rail system. Study results shows that using the conductor rail with lower resistivity requires fewer power substation, which results in lower construction cost. It also produces less copper loss. Therefore first choose the conductor rail with lowest resistivity and select the substation location, Next conduct computer simulation study to confirm it meets voltage requirement. if the minimum voltage is well above the required minimum voltage, substation number can probably be further reduced.

• Structural Engineering and Mechanics
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• 제78권1호
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• pp.87-102
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• 2021

Long span cross-rope suspension structure is an innovative structural system evolved from typical Cross-Rope Suspension (CRS) guyed tower, a type of supporting system with short span suspension cable supporting overhead power transmission lines. In mountainous areas, the span length of suspension cable was designed to be extended to hundreds or over one thousand meters, which is applicable for crossing deep valleys. Vortex Induced Vibration (VIV) of overhead power transmission lines was considered to be one of the major factors of its fatigue and service life. In this paper, VIV and its controlling by Stockbridge damper for long span CRS was discussed. Firstly, energy balance method and finite element method for assessing VIV of CRS were presented. An approach of establishing FE model of long span CRS structure with dampers was introduced. The effect of Stockbridge damper for overall vibration of CRS was compared in both theoretical and numerical approaches. Results indicated that vibration characteristics of conductor in long span CRS compared with traditional tower-line system. Secondly, analysis on long span CRS including Stockbridge damper showed additional dampers installed were essential for controlling maximum dynamic bending stresses of conductors at both ends. Moreover, factors, including configuration and mass of Stockbridge damper, span length of suspension cable and conductor and number of spans of conductor, were assessed for further discussion on VIV controlling of long span CRS.

• 대한전기학회논문지:전력기술부문A
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• 제54권5호
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• pp.234-241
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• 2005

The performance of passive conductor loop (hereinafter 'loop') method which is used to mitigate the magnetic field around overhead power transmission line is dependent on its configuration and installed location, which are affected by installation conditions of the loops such as objective areas and levels of magnetic field mitigation. Thus, because the design problem of loops is difficult and cumbersome by variety of their configuration and complexity of magnetic coupling mechanism, it is need to be formulated as a computer-based optimum problem to determine the most effective and reasonable loop model satisfying the installation conditions. In this paper, the optimum locations of the multi-wired multiple loops including series reactance compensations are searched by using the genetic algorithm (GA) to mitigate effectively the magnetic fields of relatively near points or far points from transmission line at Am height, and the magnetic fields mitigation characteristics of each loop are analyzed in the view of magnitude, direction and phase of cancellation fields by polarized vector concept to identify their adequacy and rationality for the installation objectives.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.1015-1018
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• 1999

Partial discharge patterns were analyzed in the pumped storage generator stator winding. These were measured using partial discharge analyzer(PDA) and digital partial discharge detector(PDD). Slot discharge was discovered in phase A. Discharges at conductor surface were occurred in phase B and in Phase C. Partial discharge patterns from on-line PDA system were compared with those off-line PDD system. The results of two systems are very same in phase A, B and C.

• Wind and Structures
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• 제3권4호
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• pp.243-253
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• 2000

To develop galloping suppression devices, it is important to understand the effects of wind turbulence on galloping and to establish an evaluation method which takes 'large conductor deformations' into account. This paper introduces some findings on galloping in gusty wind obtained by numerical simulation using a model based on the Mogami Test Line of the Tokyo Electric Power Co. The equations of motion of the conductor are based on the Lagrangian formulations by Simpson, and they are made discrete in accordance with a finite element method.

• 전기의세계
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• 제18권1호
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• pp.24-29
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• 1969

This is preliminary study concerning the future construction and operation of 345KV power transmission line in Korea which will be added to the existing 161KV power system by the end of 1970 in order to increase the power carrying capacity between Seoul and Pusan area; 350 kilo meters aparts, in accordance with the ambitious second five years power development schedule of Korea Electric Company. The result of this study says that an intermidiate switching station should be installed at the middle position of the line to improve the transient stability of the system, considerable amount of capacitors or synchronous condenser are to be installed to reduce the voltage drop at receving end of line during the heavy load hours, and also in some measure to avoid the voltage rise by self-excitation of power generators during the light load hours and while energizing the line. This is the first attempt to realize the EHV power transmission line in Korea so that the additional study is necessary on the kind and size of conductors, the necessary number of insulators and the suitable clearance distances between conductor and steel tower or earth from the technical and economical view points. These are necessary steps to be taken by the writer before getting into the calculation on the transient stablity of the power system.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.286-286
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• 2009

According to previous report, aged sleeves for old transmission lines have various defect such as biased installation or corrosion of steel sleeve. These defects can cause serious accidents such as rapid increasing of sag or falling out of overhead conductor from sleeves. Moreover, the defects have been limited power capacity of transmission line. This paper study on mechanical and thermal behavior of ACSR $410mm^2$ conductor and sleeve with various defect model. The conductor has been aged artificially for 50 years. The detailed results were presented in the text.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1712-1714
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• 2001

This paper deals with the development and application of an inner corrosion detector for the ACSR(Aluminum Conductor Steel Reinforced) power lines. The detector runs on an ACSR power line and inspects the inner corrosion of the conductor using the technology of the nondestructive eddy current test. It is consists of an ECT sensor, signal processing units, a RF transmitter/receiver, and etc.. The experimental result through field tests shows the detector can efficiently find both the zinc and aluminum loss of ACSR power lines.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 정기총회 및 창립40주년기념 학술대회 학회본부
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• pp.143-146
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• 1987

Fiber optics provide a solution to the problems at interference, capacity and reliability in communication. Approximately 20 kilometera of a six-fiber, multimode, longwave($1.3{\mu}m$), graded index silica glass fiber optic cable was helically wrapped around a phase conductor at a Korea Electric Power Corporation(KEPCO) 154KV transmission line. This paper presents an economic comparison of several fiber optic cable installation alternative and discusses the characteristics at the helically wrapped fiber cable, as well as the entire installation, including high voltage phase-to-ground (PTG) end termination, and splicing. The fiber link was installed for the field trial and practical use with overhead composite optical fiber cable which installation performed a few years earlier some other location and is intended to accommodate not only telephone but also supervisory Control and Data Acquisition(SCADA), protective relaying, and telemetry functions.

• 한국전기전자재료학회논문지
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• 제23권9호
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• pp.730-735
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• 2010

Forest fire can cause a serious damage to overhead conductors. Therefore, detailed investigation on the changes of mechanical and electrical properties of damaged conductors should be carried out to understand the effect of forest fires on conductors. This is of critical importance in maintaining transmission line safely. This paper examines the changes of mechanical and electrical properties of flame exposed conductor. Tensile strength (TS) decreased according to increase of forest fire temperature and conductivity changed according to forest fire temperature. Specimens were aluminum conductors of aluminium conductor steel reinforced (ACSR) 410, 240, 480 $mm^2$. In this paper, the electrical and mechanical characteristics of forest fires exposed overhead conductors depending on the diameter of aluminum conductors are presented. It was possible to estimate the degree of deterioration caused by forest fires. The detailed results are given in the paper.