Neutral-point potential balancing using synchronous optimal pulsewidth modulation of multilevel inverters in medium-voltage high-power AC drives

Abstract

This paper presents neutral-point potential (NPP) balancing while maintaining low harmonic distortion using optimal pulsewidth modulation (PWM) of a multilevel inverter for medium-voltage high-power industrial ac drives. This method is applicable for five-level inverters or higher. A high performance of the machine is observed experimentally at low-switching-frequency operation employing the proposed technique. In the past, low distortion and optimal common-mode voltage at low-switching-frequency control have been reported using proposed synchronous optimal PWM. © 1972-2012 IEEE.