A dual inverter topology controled by a voltage sliding mode in normal and fault operation

Several multilevel inverters have been proposed and extensively studied. The main topologies are the neutral point clamped inverter, the flying capacitor inverter and the cascaded connection of bridge inverters. A modular recently proposed alternative is the dual inverter configuration. This topology requires only two classical three phase voltage source inverters. One of the characteristics of this dual inverter is the high number of redundant states of the ac voltages according to the available switching combinations. Therefore, the dual inverter topology presents interesting capabilities for fault-tolerant operation. In this work, it is proposed a new controller based on a sliding mode approach and α,β vector modulator, for normal and fault operation of the dual inverter. Some simulation studies are presented in order to verify the characteristics of the proposed methodology. A comparison with the NPC multilevel topology is also presented. From this comparison it is possible to confirm the advantages of the dual inverter topology with the proposed control structure in fault operation.