DocumentCode :
1075708
Title :
Total compensation of line-side switching harmonics in converter-fed AC locomotives
Author :
Krah, Jens-Onno ; Holtz, Joachim
Author_Institution :
Wuppertal Univ., Germany
Volume :
31
Issue :
6
fYear :
1995
Firstpage :
1264
Lastpage :
1273
Abstract :
PWM controlled line-side power converters of modern AC traction locomotives inject harmonic currents into the feeding overhead line. This causes problems of electromagnetic interference. Passive or active filters are usually provided for a partial reduction of the line harmonics. A novel and superior approach employs a switched electronic compensator. It generates an exact replica of the harmonic current, feeding it to the high-voltage transformer to produce a harmonic counter MMF. The transformer main flux is then forced to be sinusoidal, and so is the induced voltage in the primary. The line current, being low-pass filtered by the transformer leakage inductance, assumes a pure sinusoidal waveform. The compensator operates in the low switching frequency range of the main power converters. Its installed power is only 1% of the traction power. Operation, control, and design considerations are described. Results from laboratory tests at full power level are presented
Keywords :
PWM power convertors; distribution networks; electric locomotives; electromagnetic interference; magnetic flux; magnetic leakage; power system harmonics; power transformers; railways; traction; AC traction locomotives; PWM line-side power converters; electromagnetic interference; feeding overhead line; harmonic counter MMF; harmonic current; harmonic currents; high-voltage transformer; line-side switching harmonics compensation; low switching frequency; low-pass filter; switched electronic compensator; transformer main flux; Active filters; Counting circuits; Electromagnetic interference; Inductance; Low pass filters; Power harmonic filters; Power system harmonics; Pulse width modulation; Pulse width modulation converters; Switching frequency;
fLanguage :
English
Journal_Title :
Industry Applications, IEEE Transactions on
Publisher :
ieee
ISSN :
0093-9994
Type :
jour
DOI :
10.1109/28.475696
Filename :
475696
Link To Document :
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