Enhancing the DC voltage utilization of twelve- switch voltage source inverter feeding symmetrical/asymmetrical nine-phase loads

Twelve-Switch Nine-Phase Inverter (TSNPI) can be used to feed three independent three-phase loads or nine-phase load such as nine-phase machines. It provides dc-ac conversion with a reduced number of switches, as only twelve switches are employed to feed the load instead of employing conventional nine- phase voltage source inverter with eighteen switches. In this paper, optimum sinusoidal modulating signals are extracted to enable operating with enhanced utilization of the dc input voltage while feeding symmetrical/asymmetrical nine-phase loads. Simulation and experimental results are presented to validate the proposed approach.