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Analysis on the Characteristics of Voltage Unbalance Factor by Load Variations  

Kim, Jong-Gyeum (국립 원주대 전기과)
Park, Young-Jeen (국립 원주대 전기과)
Lee, Eun-Woong (충남대 공대)
Publication Information
The Transactions of the Korean Institute of Electrical Engineers P / v.54, no.1, 2005 , pp. 47-53 More about this Journal
Abstract
Most of the loads in industrial power distribution systems are balanced and connected to three power systems. However, in the user power distribution systems, most of the loads are single & three phase and unbalanced, generating voltage unbalance. Voltage unbalance factor is mainly affected by load system rather than stable power system. Unbalanced voltage will draw a highly unbalanced current. As a result, the three-phase currents may differ considerably, thus resulting in an increased temperature rise in the machine. This paper presents a scheme on the characteristics of voltage and current unbalance factor under the load variation at the three phase 4-wire system. Load unbalance factor is measured by the power quality measurement apparatus and compared by the current unbalance factor. Two methods are indicated similar results. The voltage unbalance factor of the three-phase 4-wire system is approved by the field measurement. Each phase has an impedance each other by the unbalanced operation pattern and give rise to voltage unbalance.
Keywords
Unbalance Voltages; Load and Current Unbalance Factor; Power Quality;
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1 김종겸, 이은웅, '불평형 전압으로 운전시 비선형 부하 에 나타나는 현상', 대한전기학회 논문지(B), 제 51권, 6호, pp. 285-291, 2002.6
2 내선규정 제 115절, '불평형부하의 제한'
3 김종겸, 이은웅, 이동주, '불평형 전압으로 운전하는 비선형 부하의 고조파 특성분석', 대한전기학회 논문지(B), 제 52권,10호, pp. 491-500, 2003.10
4 P. Pillay and M. Manyange, 'Definitions of voltage unbalance', IEEE Power Eng, Rev. Mag., vol.5, pp.50-51, May 2001