A multilevel inverter topology for the generation of dodecagonal space vectors for medium voltage induction motor drives

In this paper, a hybrid multilevel inverter topology for the generation of dodecagonal space vectors is presented which eliminates all (6n±1), n=odd harmonics from the motor phase currents in the entire range of modulation with an increase in the range of linear modulation. The topology is a hybrid of flying capacitor, H-bridge and conventional two-level inverter cells. With this topology, any standard induction motor can now be used as the load thus avoiding the requirement of open end winding induction motors for the generation of dodecagonal voltage space vectors. A strategic variation in the PWM switching scheme is also proposed which reduces the current THD compared to conventional dodecagonal space vector based PWM schemes.