• 한국전기전자재료학회논문지
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• 제28권9호
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• pp.602-606
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• 2015

This paper presents a ZigBee wireless communication system for remote diagnosis in overhead distribution power lines. The system is divided in three parts in the functional aspect - a host computer module, a remote controller module and a diagnostic system module. The host computer module designed as USB interface transmits control signals and receive data measured by sensor. The remote controller module operates the diagnostic system. Diagnostic system module communicates with internal main controller and host computer USB. Multiple communication channel is adopted for simultaneous operations of several diagnostic system. Dedicated protocol for each module is developed. The system is designed with a focus on low cost and small size suitable for lightweight and small diagnostic system.

• 전기학회논문지
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• 제60권3호
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• pp.500-508
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• 2011

In the distribution systems, the maximum power transportation capacity is restricted within 40MW based on two lines, because of the thermal current limit of a distribution line. Recently it has been continuously required to expand the abilities of the power transportation in distribution systems, as the number of large scale industrial complexes and distributed generations are growing. In this paper, we suggested the five alternatives combining two methods, laying the two bundle lines and adding another voltage between the 22.9kV and 154kV in distribution systems. This paper implemented the economic evaluations of proposed alternatives from national and customer perspectives. And then we compare the results with those of 154kV transmission system.

• 조명전기설비학회논문지
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• 제23권5호
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• pp.110-119
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• 2009

본 연구에서는 임의의 각도로 분기되어 있는 전력선로 근방의 자계를 유도하여 정식화 하였으며 이 공식을 이용함으로써 그 자계 계산을 쉽게 할 수 있다. 이 공식들은 분기선로가 있는 배전선로의 설계 시 검토자료로서 활용할 수 있을 것으로 생각된다. 예로서 자계요소에 관한 공식들을 분기선로가 있는 3상 배전선로 모델에 적용하여 메틀랩 프로그램에 의해 계산하였으며 그 결과를 제시하였다. 그 분석결과를 요약하면 다음과 같다. 합성자계는 분기각이 작고 관측점의 높이 z가 낮으면 전 y-축상에 걸쳐 By 요소가 지배적이다. 이 합성자계는 분기각 ${\alpha}=\frac{\pi}{2}$[rad]의 경우 Bx의 영향을 크게 받는다. 또한 이 합성자계는 전력선 높이와 같은 전선로 근방에서 Bz요소가 지배적이며 분기각이 ${\alpha}>\frac{\pi}{2}$[rad]의 경우에는 y축의 분기전선 위치에서 매우 큰 값을 나타낸다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 전기설비
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• pp.118-120
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• 2005

Nowadays, economical and social environments are changing to the type of an advanced country for development of techniques in power industry. So most of workers are recently avoiding the 3D works and asking for safety of working environment, etc. in highly dangerous parts such as hot line working on distribution lines, especially. Therefore, most advanced countries are using the support-arm or robotic systems on distribution line works for securing the construction reliability, economical feasibility and protection of linemen from the electric shock and so forth. In special Japanese electric power companies are using the robotic system named manipulator. In Korea, a support-arm has been developed for safety and facility in live working on distribution lines but not widely supplied. In this paper we will introduce development cases of support arm and manipulator robot for live working on distribution lines.

• KEPCO Journal on Electric Power and Energy
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• 제7권1호
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• pp.171-177
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• 2021

In terms of distribution planning, accurate electric load prediction is one of the most important factors. The future load prediction has manually been performed by calculating the maximum electric load considering loads transfer/switching and multiplying it with the load increase rate. In here, the risk of human error is inherent and thus an automated maximum electric load forecasting system is required. Although there are many existing methods and techniques to predict future electric loads, such as regression analysis, many of them have limitations in reflecting the nonlinear characteristics of the electric load and the complexity due to Photovoltaics (PVs), Electric Vehicles (EVs), and etc. This study, therefore, proposes a method of predicting future electric loads on distribution lines by using Machine Learning (ML) method that can reflect the characteristics of these nonlinearities. In addition, predictive models were developed based on actual data collected at KEPCO's existing distribution lines and the adequacy of developed models was verified as well. Also, as the distribution planning has a direct bearing on the investment, and amount of investment has a direct bearing on the maximum electric load, various baseline such as maximum, lowest, median value that can assesses the adequacy and accuracy of proposed ML based electric load prediction methods were suggested.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 E
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• pp.1908-1910
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• 1997

The electric and magnetic fields (EMFs) near 345/154 kV overhead transmission lines were measured. The average values of maximum electric field and magnetic field for 44 transmission lines were 1.11 kV/m and 24.5 mG, respectively. These values were lower than any standards of advanced countries. The EMFs of distribution lines and substation, and electric appliances were also measured and compared with those of transmission lines.

• Journal of Electrical Engineering and Technology
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• 제6권6호
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• pp.829-835
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• 2011

A power frequency magnetic field reduction method using passive loop is presented. This method can be used to reduce magnetic fields generated within the restricted area near transmission lines by alternating current overhead transmission lines. A reduction algorithm is described and related equations for magnetic field reduction are explained. The proposed power frequency magnetic field reduction method is applied to a scaled-down transmission line model. The lateral distribution of reduction ratio between magnetic fields before and after passive loop installation is calculated to evaluate magnetic field reduction effects. Calculated results show that the passive loop can be used to cost-effectively reduce power frequency magnetic fields in the vicinity of transmission lines generated by overhead transmission lines, compared with other reduction methods, such as active loop, increase in transmission line height, and power transmission using underground cables.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.1321-1324
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• 2004

Unbalanced systems, such as distribution systems, have difficulties in fault locations due to single-phase laterals and loads. In this paper, a novel fault location algorithm is suggested for a line to line faults using inverse theorem of matrix on electric power lines. The fault location for balanced systems has been studied using the current distribution factor, by a conventional symmetrical transformation, but that for unbalanced systems has not been investigated due to their high complexity The proposed algorithms overcome the limit of the conventional algorithm using the conventional symmetrical transformation, which requires the balanced system and are applicable to any electric power system but are particularly useful for unbalanced distribution systems. The simulation results oriented by the real distribution system are presented to show its effectiveness and accuracy.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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• pp.585-587
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• 1998

In 22.9 kV-Y distribution lines, Several kinds of over-voltages occur. These over-voltages are usually surge types except controling the bus voltages for line voltage drop. The measuring over-voltages in 22.9 kV lines is a very difficulty skill. This paper introduces the study on the measurement system of over-voltages in 22.9kV distribution lines. It has been researching in KEPCO since 1995.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 춘계학술대회 논문집 전기설비전문위원
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• pp.54-56
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• 2005

On the overhead distribution lines, we generally use a copper rod as a grounding electrode. It is a economical metallic structure. Recently, many new electrodes have been developed and used in the distribution system of KEPCO. Before using new grounding electrode. we need to measure the performance of each electrode for comparative analysis. This report describes the characteristic test of the grounding electrodes used in KEPCO.