• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.872-873
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• 2015

여러 전력기기를 안전성과 편의성 등을 위하여 함(enclosure)에 설치하였을 때, 이러한 제품을 배전반(Switchgear and controlgear assemblies)이라고 한다. 내부에 설치되는 기기들을 서로 접속할 때 전선(cable) 또는 부스바(busbar)를 사용하고 있는데, 사용시 필연적으로 전력손실에 의한 발열로 인하여 배전반 내부온도 및 기기의 온도가 상승한다. 기기에 대한 온도 상승 허용범위는 각 기기의 해당규격에 규정되어 있으며 배전반 규격(고압배전반 : IEC 62271-200 및 SPS-KEMC 2101-0609, 저압배전반 : IEC 61439 series 및 SPS-KEMC 2102-0610)에는 외부접속용 단자 등 배전반 내부에 사용되는 전선 또는 부스바의 온도상승 허용범위가 규정되어 있다. 본 고찰에서는 배전반의 각 정격전류에 따른 전선 또는 부스바의 사이즈, 특히 부스바의 사이즈 및 형상에 따른 온도상승의 영향을 살펴보고자 한다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.663-664
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• 2015

본 논문에서는 전기자동차의 인버터-전동기 연결 구성에 따른 전도성 잡음 특성에 대해 분석 하였다. 인버터와 전동기를 연결하는 케이블은 임피던스를 가지고 있으며, 케이블 길이별 특성 시뮬레이션에서 주파수에 따른 임피던스가 다르게 나타나는 것을 알 수 있다. 이러한 특성을 고려하기 위해, 인버터와 전동기를 연결하는 케이블 길이에 차이를 두어 시뮬레이션을 진행 하였으며, 인버터 전동기가 일체화되어 케이블 없이 부스바(Busbar)로 연결된 형태에 대해서도 시뮬레이션을 진행 하였다. 시뮬레이션 결과에서 Busbar 형태 및 케이블 길이에 따른 전도성 잡음의 변화는 거의 없는 것을 확인 할 수 있었다.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.4
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• pp.214-220
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• 2004

This paper describes a busbar current differential relay in conjunction with a current transformer(CT) compensating algorithm irrespective of the level of the remanent flux. The compensating algorithm detects the start of first saturation if the third-difference function of the current exceeds the threshold; it estimates the core flux at the first saturation start by inserting the negative value of the third-difference function of the current into the magnetization curve; thereafter, it calculates the core flux during the fault and compensates the distorted current using the magnetization curve. The algorithm estimates the correct secondary current irrespective of the level of the remanent flux and needs no saturation point of the magnetization curve. The proposed relay can improve not only security of the relay on an external fault with CT saturation but sensitivity of the relay on an internal fault; the relay can improve the operating speed on n internal fault with CT saturation. This paper concludes by implementing the relay into a digital signal processor based prototype relay.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.4
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• pp.214-214
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• 2004

This paper describes a busbar current differential relay in conjunction with a current transformer(CT) compensating algorithm irrespective of the level of the remanent flux. The compensating algorithm detects the start of first saturation if the third-difference function of the current exceeds the threshold; it estimates the core flux at the first saturation start by inserting the negative value of the third-difference function of the current into the magnetization curve; thereafter, it calculates the core flux during the fault and compensates the distorted current using the magnetization curve. The algorithm estimates the correct secondary current irrespective of the level of the remanent flux and needs no saturation point of the magnetization curve. The proposed relay can improve not only security of the relay on an external fault with CT saturation but sensitivity of the relay on an internal fault; the relay can improve the operating speed on n internal fault with CT saturation. This paper concludes by implementing the relay into a digital signal processor based prototype relay.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.31-33
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• 1998

In this paper, the temperature rise within busbar part of high voltage GIS is calculated under the condition that the continuous current is carrying. Heat transfer by conduction and convection is considered between the current carryig conductor and SF6 gas. FLUX 2D which is a commercial electromagnetic and thermal analysis program is used. The results show reasonable temperature distribution.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.5
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• pp.313-319
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• 2000

In order to design the current carrying conductor for GIS, it is important to predict temperature-rise when rated current flows in the bus bar. However, it is not easy to apply the correct heat transfer coefficient on the boundary between different material for the thermal analysis. In this paper, the heat transfer coefficient which depends on parameters such like material constant, model geometry as well as ambient temperature, was calculated by analytic method. The calculated coefficient is used for the temperature rise prediction by F.E.M. The results show good agreement with experimental data.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2003.11a
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• pp.103-105
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• 2003

The principle of the ultra-high frequency (UHF) method to detect partial discharge(PD) in GIS is to measure the UHF electromagnetic waves excited by PD pulses. Such electromagnetic waves propagate along the GIS busbar in the TEM-mode, TE-mode, TM-mode. And the coaxial busbar of the GIS acts as a waveguide in which the UHF electromagnetic waves travel. This paper was studied the analysis on damping characteristic of electromagnetic waves excited by PD in GIS and presented the method to yield the cutoff frequency for determine the minimum band of sensor that detect the PD pulse.

• Proceedings of the KIPE Conference
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• 2008.10a
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• pp.61-63
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• 2008

An inverter with large capacity has been demanded at a factory automation and diffusion of the energy saving work. As the capacity of inverter is larger, the stary inductance has much influence on both the di/dt of IGBT current, and voltage stress across IGBT. Also, the life of the snubber capacitor may be shortened due to overheating of the snubber capacitor. In this paper, a planar busbar which consists of two layers is applied to N700-series inverter in order to minimize stray inductance. The voltage stress across IGBT is changed by both the DC busbar structure and the capacity of snubber capacitor.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.823-824
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• 2016

In general, distribution board, panel board and motor control center can be installed over a wide area such as residence of group, building, schools, factories, ports, airports, water service and sewerage, substation and heavy industries that are used to supply converts the voltages extra high voltage into optimal voltage. There are electrical accidents due to rise of contact temperature, loose contact of bus bar, deterioration of the contact resistance, overtemperatue of the bus bars. In this paper, we propose bus bar joints monitoring system with loose connection of bus bar, measuring the joint resistance of busbars and monitoring internal and external heat. The proposed system can be reduced the electrical accidents by maintenance of busbar joints and the temperature of the conductive contact surface of busbars.

• Current Photovoltaic Research
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• v.7 no.3
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• pp.65-70
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• 2019

As a demand of higher power photovoltaic modules, shingled, multi-busbar, half-cell, and bifacial techniques are developed. Multi-busbar module has advantage for large amount of light havesting. And, half-cell is high power module for reducing resistive losses and higher shade tolerance. Recently, researches on multi-busbar is focused on reliability according to adhesion and intermetallic compound between Sn-Pb solder and Ag electrode. And half-cell module is researched to comparing with full-sized cell module for structure difference. In this study, we investigated the factors affecting to efficiency and adhesion of multi-wires half-cell module according to wire thickness, solder thickness, and flux. The results of solar simulator and peel test was that peel strength and efficiency of soldered cell is not related. But samples with flux including high solid material showed high efficiency. The results of FE-SEM and EDX line scan on cross-section between wire and Ag electrode for different flux showed thickness of solder joint between wire and Ag electrode is increasing through solid material increasing. Flux including high solid material would affect to solder behavior on Ag electrode. Higher solid material occurred lower growth of IMC layer because solder permeate to sider of wire ribbon than Ag electrode. And it increased fill factor for high efficiency. In soldering process, amount of solid material in flux and solder thickness are the factor related with characteristic of soldered photovoltaic cell.