Highfrequency AC/DC converter with unity power factor and minimum harmonic distortion
Abstract
The power factor is controlled by adjusting the relative position of the fundamental component of an optimized PWMtype voltage with respect to the supply voltage. Current harmonic distortion is minimized by the use of optimized firing angles for the converter at a frequency where GTO's can be used. This feature makes this approach very attractive at power levels of 100 to 600 kW. To obtain the optimized PWM pattern, a steepest descent digital computer algorithm is used. Digitalcomputer simulations are performed and a lowpower model is constructed and tested to verify the concepts and the behavior of the model. Experimental results show that unity power factor is achieved and that the distortion in the phase currents is 10.4% at 90% of full load. This is less than achievable with sinusoidal PWM, harmonic elimination, hysteresis control, and deadbeat control for the same switching frequency.
 Authors:
 Publication Date:
 Research Org.:
 Mississippi Univ., University (USA)
 OSTI Identifier:
 6378134
 Alternate Identifier(s):
 OSTI ID: 6378134
 Resource Type:
 Thesis/Dissertation
 Resource Relation:
 Other Information: Thesis (Ph. D.)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 24 POWER TRANSMISSION AND DISTRIBUTION; ALTERNATING CURRENT; POWER FACTOR; DC SYSTEMS; CONVERSION; ALGORITHMS; COMPUTERIZED SIMULATION; CURRENTS; ELECTRIC CURRENTS; ENERGY SYSTEMS; MATHEMATICAL LOGIC; POWER SYSTEMS; SIMULATION 200300*  Electric Power Engineering Power Transmission & Distribution (1989)
Citation Formats
Wernekinch, E.R. Highfrequency AC/DC converter with unity power factor and minimum harmonic distortion. United States: N. p., 1987.
Web.
Wernekinch, E.R. Highfrequency AC/DC converter with unity power factor and minimum harmonic distortion. United States.
Wernekinch, E.R. Thu .
"Highfrequency AC/DC converter with unity power factor and minimum harmonic distortion". United States.
doi:.
@article{osti_6378134,
title = {Highfrequency AC/DC converter with unity power factor and minimum harmonic distortion},
author = {Wernekinch, E.R.},
abstractNote = {The power factor is controlled by adjusting the relative position of the fundamental component of an optimized PWMtype voltage with respect to the supply voltage. Current harmonic distortion is minimized by the use of optimized firing angles for the converter at a frequency where GTO's can be used. This feature makes this approach very attractive at power levels of 100 to 600 kW. To obtain the optimized PWM pattern, a steepest descent digital computer algorithm is used. Digitalcomputer simulations are performed and a lowpower model is constructed and tested to verify the concepts and the behavior of the model. Experimental results show that unity power factor is achieved and that the distortion in the phase currents is 10.4% at 90% of full load. This is less than achievable with sinusoidal PWM, harmonic elimination, hysteresis control, and deadbeat control for the same switching frequency.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jan 01 00:00:00 EST 1987},
month = {Thu Jan 01 00:00:00 EST 1987}
}

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