A novel three-phase AC/DC converter without front-end filter based on adjustable triangular-wave PWM technique

摘要

This paper proposes a novel three-phase AC/DC converter without a front-end filter. Because an adjustable triangular-wave pulsewidth modulation (PWM) (ATPWM) technique is adopted, not only is a front-end filter located after the three-phase rectifier is omitted, but also the size of the input AC filter and the output DC filter are reduced. In addition, this AC/DC converter has many advantages such as simpler structure, higher reliability, and better output waveform. The principle of operation, harmonics elimination, and feedback control of the novel AC/DC topology are elaborated. A thorough analysis on its performance under an unbalanced system is presented. Finally, the theoretical analysis is proved to be correct by simulations and experiments.