Changing Preprogrammed Selective Harmonic Eliminated PWM for Three-Level NPC AFE Rectifier

Power converters efficiency depends largely on pulse-width modulation (PWM) methods. The currently existing preprogrammed selective harmonic eliminated PWM (PPWM SHE) methods have been created to improve the power quality and optimize electric losses. PPWM SHE uses pre-calculated switching tables of semiconductor modules, it can be changed during the operation modes to define the best variant. This paper focuses on designing the PPWM SHE changing algorithm for three-phase three-level neural point clamped (NPC) active front-end (AFE) rectifier. The obtained experimental results have been presented. The proposed algorithm has prospects, in particular, in the field of wind power, metallurgical rolling mills and powerful ship electric drives, where high-power three-level NPC AFE rectifiers are used.