• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.3
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• pp.117-124
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• 2007

This paper is about the Extra-High voltage distribution system in the customer's area. The power loss in the distribution system in the customer's area is disregarded and rarely managed so far. But, economically, this loss is not small quality to ignore. So, in this paper, we calculate the power loss of the Extra-High voltage distribution system in the customer's area by changing the locations of power transformer and other power facilities to decrease power loss in decreased secondary line length. And we also show the payback time of the proposed Extra-High voltage distribution system in the customer's area by simplified calculations.

• Proceedings of the KIEE Conference
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• 2002.11a
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• pp.112-115
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• 2002

The effects of processing aids(P.A.) in semicoductive compounds(S.C.) with highly loaded carbon black for extra high voltage cables were investigated. The processability of S.C. is improved as the contents of P.A. increased, however, the electrical, mechanical properties and smoothness of S.C. grew worse, especially for the S.C. which contains 5wt% of P.A., the volume resistivity after heat cycle which shows long term reliability increased about three times after 15cycles compared to the S.C. which contains no P.A. We inferred that it is caused by the action of P.A. as the insulating sites, thermal expansion of polymer matrix which leads the length between carbon blacks to shorten, and the decrease of degree of crosslinking. The change of ion contents which means cleanliness of S.C. is not occured regardless of the addition of P.A.

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.4
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• pp.155-160
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• 2005

This paper addresses the discharge characteristics of cross-linked polyethylene according to void by the Weibull function. It analyzes discharge number and amount of discharge using Weibull distribution to identify the inter-relationship between partial discharge and defect. We detected a 10 second discharge. The applied voltage increased by 1 [kV] at discharge inception voltage. As a result, in a no-void specimen, the shape parameter was consistent according to the increase of voltage, whereas, in a void specimen, it increased according to the increase of voltage. As the result, the shape parameter expressed a fixed value at no-void specimen. However, in void specimen, according to increasing voltage shape parameter rapidly increases.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.5
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• pp.391-396
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• 2001

The purpose of this study is to investigate the effect of hole or crack on the Insulation characteristics of a PET films for EHV(Extra High Voltage) VT winding. The hole or the crack in the PET films was made and the insulation characteristics of them were measured. Ad an experimental result, it was shown hat he PDIV(Partial Discharge Inception Voltage) and the BDV(Breakdown Voltage) of the PET films with hole or crack were lower than those without them, and were markedly dependent on their position and temperature. Therefore, the hole and the crack affected to insulation characteristics of PET films for SF$_{6}$EHV(Extra High Voltage) VT Winding.g.

• Proceedings of the KIPE Conference
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• 2019.07a
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• pp.11-13
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• 2019

This paper proposes a novel high step-up non-isolated DC-DC converter, suitable for regulating dc bus in various inherent low voltage micro sources especially for photovoltaic (PV) and fuel cell sources. This novel high voltage Non-isolated Boost DC-DC converter topology is best replacement, where high voltage conversion ratio is required without the transformer and also need continuous input current. Since the proposed topology utilizes the stack-based structure, the voltage gain, and the efficiency are higher than other conventional non-isolated converters. Switches in this topology is easier to control since its control signal is grounding reference. Also, there is no need of extra gate driver and extra power supply for driver circuit, which reduces the cost and size of system. In order to show the feasibility and practicality of the proposed topology principle operation, steady state analysis and simulation result is presented and analyzed in detail. To verify the performance of proposed converter and theoretical analysis 360W laboratory prototype is implemented.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.3
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• pp.50-55
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• 2007

A large steel industry which has nonlinear loads including electric arc furnaces is one of the extra high voltage customers. These nonlinear loads generate harmonic currents and create distortions on the sinusoidal voltage of the power system. Harmonic field measurements have shown that the harmonic contents of a waveform varies with time. A cumulative propablistic approach is the most commonly used method to solve time varying harmonics. In this paper the in varying harmonics of electric arc furnace loads are evaluated by international harmonic standards(IEC 61000-3-6, IEEE 519 and JIS C 61000-3-2).

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1704-1706
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• 2002

With increasement of use in electricity energy, quality of electric apparatus has been recognized as important factor in distribution and transmission line. Especially In laboratories, lightning and switching impulse performances of electric apparatus have been carrying out by impulse voltage generator (IVG), simulated into lightning and switching surge circuit. In this paper, we describe triggering system of impulse voltage generator(IVG) for extra high voltage, which has been newly designed.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.61 no.2
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• pp.82-86
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• 2012

Recently, due to the expansion of electric power demands, nonlinear load such as converters and inverters connected to the electric power distribution system, and extensive application of harmonic generation sources with power electric devices, disturbance of the electric power system and its influences on industries have been continuously increasing. In this research, power quality was analyzed for 11 extra-high voltage customers by considering voltage unbalance condition, power factor, THD and TDD. This research will be utilized as fundamental data to improve power quality for power utility.

• JOURNAL OF ELECTRICAL WORLD
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• no.12 s.132
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• pp.38-46
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• 1987

• JOURNAL OF ELECTRICAL WORLD
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• no.4 s.124
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• pp.41-48
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• 1987