A Study of Voltage Flicker and Resonance at Power Systems of Arc Furnaces
| Autor: | Wen-Lung Yang, 楊文隆 |
|---|---|
| Rok vydání: | 2004 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 92 In steel arcing factories, reactive power fluctuations caused by heavy- duty nonlinear loads result in the voltage variations and flickers appearing on system site. The harmonic currents generated on load site are normally suppressed by passive filters. This, however, may cause harmonic current amplification, parallel resonance as well as raising the flicker voltage level due to improper design of passive filters. This thesis is concerned with the analysis of the aforementioned parallel resonance, the suppression of harmonic current and the improvement of higher flicker voltage. The major contribution of this thesis is to propose the use of parallel impedance method to obtain the minimum impedance and maximum reactive power for the worst-case flicker estimation and calculation, and to reduce the difference between theoretical calculations and field measurements after installing static var compensator. In addition, when the electric arc furnace is in one of the three different modes of operation, namely the open-circuit, continuous-arcing and short-circuit cases, this thesis also conducts resonance frequency analysis for correcting filters design, suppressing harmonic current and improving voltage flickering. Besides, when considering all the harmonic currents flowing into each filter, this thesis compares the difference between nominal specification under power frequency and that required under harmonic load condition and gives detail analysis to facilitate the design and parameter selection of passive filters for higher performance and reliability. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
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