Space Vector Modulation for High-Power Three-Level NPC Rectifiers Without Even Order Harmonics
Space vector modulation (SVM) is a preferred PWM scheme for multilevel converters mainly due to its flexibility, easy digital implementation and good harmonic profile. However, the conventional SVM scheme normally produces even-order voltage/current harmonics at the rectifier inputs. The even-order harmonic currents are strictly regulated by the harmonic guidelines such as the IEEE Standards 519-1992 in North America. In this paper, the mechanism of even-order harmonic generation is analyzed, and a new SVM scheme that has the ability to eliminate these harmonics is proposed for three-level neutral point clamped (NPC) rectifiers. The harmonic profile of both schemes is investigated by computer simulation. The effectiveness of the proposed scheme is experimentally verified