Techniques for minimizing the input current distortion of the current-controlled single-phase boost rectifier

Techniques for minimizing the input current distortion of current-controlled single-phase boost rectifiers are described. The switching patterns of several boost rectifiers are examined to identify the nature of their input current waveforms. This analysis is then used to examine the low-frequency current distortion levels, and hence the power quality, associated with the rectifiers. A pulse width modulation (PWM) strategy that selectively switches between positive unipolar PWM and negative unipolar PWM, phase-adjusted unipolar PWM, is shown to produce the lowest current distortion levels. A novel asymmetrical half-bridge rectifier is presented that produces a unity power factor input current with low distortion. Extensive analyses of the circuits used are undertaken with reference to theoretical predictions circuit simulators, and experimental results