ALL IGBT UPS SYSTEM AND CONTOL METHOD THEREOF

摘要

An All IGBT UPS system and a controlling method thereof are provided to separate fifth or seventh harmonic components and to cancel out them to prevent the noise and loss in a transformer and a reactor. An All IGBT UPS system comprises a current distortion factor controller, which consists of a phase-discriminating unit(910), a second and third synchronization converting unit(920, 930) and a low pass filter(940). The phase-discriminating unit discriminates input voltage into an elementary wave, a fifth phase and a seventh phase using a PLL method. The second and third synchronization converting unit converts the input voltage and detects 2-phase voltage. The low pass filter removes the ripple from the output of the second and third synchronization converting unit.