A hybrid multilevel inverter topology for drive applications

The use of multilevel inverters has become popular in recent years for high power applications. Various topologies and modulation strategies have been reported for utility and drive applications in the recent literature. This paper is devoted to the investigation of a 500 hp induction motor drive based on a seven-level 4.5 kV hybrid inverter. The topological structure and operating principles of the proposed approach are presented. Various design criteria, spectral structures and other practical issues such as capacitor voltage balancing are discussed. The feasibility of the proposed approach is verified by computer simulations.