A new five-level inverter system for an induction motor with open-end windings

In this paper, a new 5-level inverter system for an open-end winding induction motor drive is described. Multilevel inversion is achieved by feeding an open-end winding induction motor with an asymmetrical 3-level inverter from one end and a 2-level inverter, from the other end. The combined inverter system with open-end winding induction motor produces voltage space vector locations identical to a 5-level inverter. A total of 512-space vector combinations are distributed over 61 space vector locations in the proposed scheme. The proposed inverter drive scheme is capable of producing a multilevel PWM waveform for the phase voltage ranging from a 2-level waveform to a 5-level waveform depending on the depth of modulation.