• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2317-2319
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• 1999

765kV Transformer, bank capacity is 2,000MVA, is developed of two seperated tanks per phase because transportation weight of the transformer needs to be reduced. So we will operate one tank per phase in some case, low load or black down of 1 tank, using the one phase-two tank type of 765kV transformer to cut down the cost and improve the reliability of substation.

• Proceedings of the KIEE Conference
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• 2004.05b
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• pp.152-155
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• 2004

99년 장기 송변전 설비계획에 의거하여 765kV 신안성 T/L이 2회선에서 1회선으로 기본계획이 변경되면서 이의 건설과 운용을 위하여 1회선 선로 건설을 위한 송전 철탑의 설계 및 제작이 시행되었고 실 선로 운용 전에 신뢰성 검토를 위하여 전기적, 기계적 특성을 파악해야할 필요성이 제기 되었다. 이와 관련하여 한전 전력연구원에서는 765kV 1회선 시험선로를 구축하고 하중시험을 실시하였다. 이 논문에서는 765kV 1회선 삼각배열 시험 송전철탑 철탑 관련 연구개발 내용 및 신뢰성 확보를 위해 실시된 하중 시험 등에 대하여 기술하였다.

• Proceedings of the KIEE Conference
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• summer
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• pp.452-454
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• 2004

An accurate digital distance relaying algorithm which is immune to reactance effect of the fault resistance and the load current for phase-to-ground fault in 765kV untransposed transmission lines is proposed. The algorithm can estimate adaptively the impedance to a fault point independent of the fault resistance. To compensate the magnitude and phase of the apparent impedance, this algorithm uses the angle of an impedance deviation vector. The impedance correction algorithm for Phase-to-ground fault uses a voltage equation at fault point to compensate the fault current at fault point. A series of tests using EMTP output data in a 765kV untransposed transmission lines have proved the accuracy and effectiveness of the proposed algorithm.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.11
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• pp.1365-1373
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• 1999

In many countries including Korea, in order to transmit the more electric power, the higher transmission line voltage is inevitable. So, a rapid reclosing scheme is important for EHV/UHV transmission lines to ensure requirements for high reliability of main lines. A critical aspect of reclosing operation is the extinction of the secondary arc since it must extinguish before successful reclosure can occur. Therefore the accurate simulation techniques of arcing faults are of importance. And successful reclosing switching can be accomplished by adopting a proper method such as HSGS and hybrid scheme to reduce the secondary arc extinction time. First of all, this paper discusses a suggested arc model, which have time dependent resistance for primary arc and piecewise linear approximated arc model for secondary arc. And this simulation technique is applied to Korean 765 kV transmission lines. Also hybrid scheme is simulated and evaluated for the purpose of shortening dead time. For adaptive reclosing scheme, variable dead time control algorithm is suggested. Two kinds of algorithm are tested. One is max tracking algorithm and the other is rms tracking algorithm. According to simulation results, rms tracking has less errors than max tracking. Therefore rms tracking is applied to Korean 765 kV transmission lines with hybrid scheme.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.837-1-837-3
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• 1998

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1899-1902
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• 2002

KEPCO is planning to operate 765kV Sin-Tao-Back and Sin-Ga-Pyong substations from 2004. A preventive diagnostic system to obtain the reliability of transformer and GIS is being adopted in 765kV substations. KEPRI has developed a preventive diagnostic system for 765kV substation since 1997. The preventive diagnostic system developed in that project was installed to the 345kV Eui-Ryung substation in June, 2000, and it is under circumstance durability test and operation capacity tests. In this paper, we analyze data of the preventive diagnostic system in 345kV Eui-Ryung substation.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.9
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• pp.1632-1637
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• 2007

This paper analyses current densities induced inside human body of lineman for 765kV transmission line when he wears a protective cloth or not. Applying the boundary element method, we calculate current densities induced in organs inside a worker in case he was located at 15[cm], 30[cm], 50[cm], and 100[cm] far from a prefabricated jumper. As results of study, we find a maximum current density induced in all organs may be higher than $10[mA/m^2]$ if he does not wear protective clothes. We also know high permeability materials can lower current density more than high conductivity materials.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.5
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• pp.231-238
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• 2006

This paper analysed the induced current density inside human body of hot-line worker for 765kV double circuit transmission line according to locations of human body. Human model was composed of several organs and other parts, whose shapes were expressed by spheroids or cylinders. Organs such as the brain, heart, lungs, liver and intestines were taken into account. Applying the 3 dimensional boundary element method, we calculated induced current density in case a worker was located inside and outside a lowest phase of 765 kV transmission line in which a 60% current of maximum load flowed. As results of study, we found a maximum induced current density in all organs was less than $10mA/m^2$ when a wonder was outside. As one in brain and heart was higher than $10mA/m^2$ when a worker was inside, we propose a method for lowering current density.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.1
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• pp.25-30
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• 2005

An accurate digital distance relaying algorithm which is immune to mutual coupling effect and reactance effect of the fault resistance and the load current for the line faults in 765kV untransposed transmission lines is proposed. The algorithm can estimate adaptively the impedance to a fault point independent of the fault resistance. To compensate the magnitude and phase of the apparent impedance, this algorithm uses the angle of an impedance deviation vector. The impedance correction algorithm for phase-to-ground fault and phase-to-phase short fault use a voltage equation at fault point to compensate the fault current at fault point. A series of tests using EMTP output data in a 765kV untransposed transmission lines have proved the accuracy and effectiveness of the proposed algorithm.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.723-724
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• 2007

Live line work is well known for mending and maintenance of electrical power equipment. Nowadays needs of electric power supply quality require live line work In Korea, live line work is needed since 765kV transmission operation and restructure of electric power industry has changed. In other words, in case of suspension of power supply on the transmission is getting hard to keep up with efficiency of transmission operation, customer's confidence and generation-limited cost. Therefore live line work is very meaningful. As the condition of 765kV Transmission both bare hand and Helicopter live line technique must be used in moderation because of economic, geographical, environmental circumstances around steel tower.