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A Probabilistic Analysis on the Harmonic Cancellation Characteristics of the Scott Transformer
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Journal of Electromagnetic Analysis and Applications·Volume 02 (2010)·Pages 18–24·Published 28 January 2010·DOI10.4236/jemaa.2010.21003
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Abstract
The Scott transformer is widely used in electric railway systems when there are two unbalanced single-phase loads as this transformer can reduce unbalance currents. This paper investigates whether or not the Scott transformer can also reduce harmonic current. Our study shows that it can reduce the harmonic current when single-phase loads have identical harmonic characteristics. This harmonic reduction occurs through the cancellation of harmonic currents of single-phase loads in the transformer windings. Our studies also show that there is some degree of cancelation even when the loads do not have identical harmonic characteristics. The cancellation depends on load balance factor and harmonic order.
KeywordsTerms-HarmonicsHarmonic CancellationScott TransformerProbabilisticPower Quality
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