• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.265-268
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• 2005

This paper discusses a strategy and status for development and operation of durability mock-up test facilities for offshore structures. The strategy is examplified and facilitated using an offshore transmission tower crossing the West sea and the Shihwha lake, which was designed and constructed 345kV T/L lines transmitting power from Yeong-Heung fossil power plant to Seoul metropolitan area. Various data for corrosion protection, aging, life-prediction of concrete and steel offshore structures can be obtained using the proposed mock-up test facility. Acquired data will be used for further research on durability, life-prediction, and retrofit of structures. It is important to maintain the safety of 345 kV Yeong-Heung transmission line crossing the Shihwha lake because the offshore structure is one of the critical electric facilities transmitting large power to the metropolitan area. Operation of the offshore transmission tower mock-up is expected to make a significant contribution to stable power supply.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1678-1680
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• 1998

The purpose of this study is to obtain optimum arrangement of phase conductors in minimizing magnetic field from overhead transmission lines. Data of the transmission lines rated 345 kV of the KEPCO(Korea Electric Power Company)'s system were used. For a three phase-double circuit transmission line, low-reactance arrangement is optimum in minimizing magnetic fields. For a three phase-four circuit, optimum phase arrangement is a-b-c-b-a-c(lower two circuits, clockwise)/b-c-a-c-a-b(upper two circuits, clockwise).

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1881-1883
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• 2002

Recently, 345kV XLPE Cable and Accessories have been developed and will be applied for Youngseo$\sim$Youngdeungpo project in Korea. So, let this project and the process of development introduce on this paper. The cable type and length of this project is 345kv XLPE 1C*$2000mm^2$ 66km and all cable will be pulled on cable tunnel. The diameter of cable insulation was designed as 27mm, we could reduce it by appling for hi-tech and super-clean system. Joints were developed by a pre-fabricated type which considered high safety and economic issues. We had also done Pre-Qualification test for verifying the reliance of cable and accessories before construction. As we developed this 345kV XLPE cable system including its accessories at the same time, we can have higher technologies and contribute safe power in transmission lines. In adtionally, we can have a stable status for suppling EHV cable systems to a variety foreign customers by ourselves.

• 한국산업융합학회 논문집
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• 제14권3호
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• pp.121-125
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• 2011

EMTP-RV is the very powerful program to analyze the dynamic operation of the power system. To use this package in the large complex power system, it is very important to simplify the power system to simple equivalent network. In our study the 100 MVA STATCOM is placed at 345kV "MIGUM" which is the one of the 345kV substations of the Korean Electric Power System that is consist of more than 1000-bus. MIGUM substation is connected with 7 separated transmission lines to main Korean Electric power system. We developed a new method to simplify the network except the substation that we want to analysis. The power system outside the 345kV substation is modeled into the equivalent network. The loop network outside the substation can be modeled to simplified Thevenin equivalent network. The proposed method is applied to IEEE-14 Reliability Test System and the results shows the effectiveness of the method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.60_61
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• 2009

최근 국내에서 345kV GIL(Gas Insulated Transmission Lines) 시스템의 실 계통 도입이 검토되고 있다. 현재까지 GIL은 원자력 발전소에서 주변압기로부터 스위치 야드까지 1km 미만의 거리에 소규모로 설치되어 운영되고 있다. 하지만 향후 본격적으로 GIL 시스템이 도입된다면 발전소 구내뿐만 아니라 수 km 이상 되는 송전급 선로에도 적용될 것이 예상된다. 현재 GIL의 시스(외함)는 100~120m 정도마다 접지를 하는 직접접지 형태를 취하고 있으나 시스에 흐르는 순환전류가 부하전류의 97% 이상 된다. 따라서 이에 따른 손실이 많이 발생되고 있어 도체에 흘릴 수 있는 허용전류 값이 감소하게 된다. 본 논문에서는 GIL 시스템에 크로스본드 접지방식을 적용하였을 때 시스 순환전류 감소 효과에 대해서 검토하고, 아울러 뇌써지나 스위칭 써지에 의한 절연통의 열화 등에 대비하기 위하여 절연통보호장치의 설치 방안에 대해서 검토하였다.

• 전기학회논문지P
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• 제58권3호
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• pp.323-327
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• 2009

The oscillation is very dangerous in bundled transmission lines, besides 4 bundle transmission lines are very weak for subspan oscillations. In some cases, subspan oscillations are continuously occurred in the same subspan. In order to develop the control method of the above subspan oscillation, this paper suggests a method of applying twin spacers to the subspans. We have carried out some tests to analyze the oscillation phenomena after installing twin spacers on 4 bundle overhead lines, and we got a good effect for controling subspan oscillations by installing twin spacers.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1193-1195
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• 1997

The chief advantage of these NCI, from a handling viewpoint. was an up to 90% weight reduction over their porcelain counter. Diagnosis and the life expectancy of NCI for transmission lines depend on a number of factors, many of which are associated with natural tracking breakdown, while others are related to manufacturing conditions. Recently The importance of optimizing a NCI for good performance under a wide variety of test condition and diagnosis is emphasized ; as well as the increased importance of natural breakdown testing. Today, at transmission lines, NCI have become very popular at 154 through 345 kV.

• 한국안전학회지
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• 제36권5호
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• pp.10-17
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• 2021

The controversy over the risk of the human body being affected by electromagnetic fields emitted from 60 Hz power lines continues without end. There are currently no new studies or research progress being made in this direction that is notable, and the number of civil complaints is gradually increasing. The problem is that each study produces different results, among which the effect of exposure to magnetic fields on childhood leukemia is a major one. In Korea, an electrician who was maintaining a 22.9 kV power line died of leukemia, which has recently been recognized as an occupational disease. Methods to reduce magnetic fields from power lines include shielding with wire loops, incorporating split phases and compaction techniques, installing underground power lines, converting to high-voltage direct current (HVDC), and increasing the ground clearance of transmission towers. Depending on whether a separate power supply is needed or not, there are two types of wire loops: passive loop and active loop. Magnetic field reduction is currently done through underground power lines; however, the disadvantage of this process is high construction costs. Installing passive loops, with relatively low construction costs, leads to lower magnetic field reduction rates than installing underground cables and a weakness to not solving the landscape problem. This methodological study aims at designing methods and reducing the effects of 2-wire set loops-the simplest and most practical. Since the method proposed in this study has been designed after analyzing the distribution of complex electromagnetic fields near the expected loop installation location, a practical design can be implemented without the need for any difficult optimization programming.

• 한국전기전자재료학회논문지
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• 제22권10호
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• pp.870-878
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• 2009

The large increase in the use of electricity has resulted in an ever-growing electric power demand. It has created the need for the construction of power transmission facility located close to the load centers and it also has to require wide right-of-way and large lots, that are not always available, for especially the installation of the towers. The difficulties in acquiring right-of-way have put pressure on energy companies to either upgrade a line on an existing right-of-way to higher voltage or build a new line on a narrow right-of-way. This paper presents the design of a compact tower with polymer Insulation arm, in order to reduce the separation between phases. the compact tower can be built on a narrow right-of-way. the compact tower can be designed based on 345 kV Tower regarding electrical clearances and right of way, therefore the conventional 154 kV Tower can be upgrading transmission line voltages have moved to 345 kV levels.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1142-1144
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• 1999

본 논문에서는 최근 선진국에서 활발히 연구중인 EMF 차폐 대책의 일환인 수동 루프에 대한 이론적 분석 방법을 기술하고, 송전선로 자계 저감 효과를 실제 우리나라 345kV, 765kV를 대상으로 정량적 효과를 분석하였다. 그 결과 수동 루프를 적용한 경우, 약 30% 정도의 자계 저감 효과를 나타내어 전력설비의 유효한 대책임을 확인하였다.