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

This paper presents neutral point potential (NPP) balancing while maintaining low harmonic distortion using optimal pulsewidth modulation (PWM) of multilevel inverter for medium voltage high power industrial AC drives. This method is applicable for five-level inverters or higher. 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 pulse modulation.