A New Topology for Three-Phase Multilevel Voltage Source Inverters Based on DC Power Supply with Reduced Number of Switches and Diodes

In this paper a new topology is introduced for three-phase inverter that includes a multi-level module, a three-phase inverter bridge and middle levels selection unit. The main advantage of proposed topology is using fewer switches and diodes to reach the maximum level of output voltage. The structure consists of a single-phase multilevel module; three bidirectional switches and a three-phase inverter bridge. The other capability of this structure is increasing of two level of output voltage just by adding a bidirectional switch and a low voltage capacitor. In this paper is proposed the switching sequences to access for any number of output voltage levels. Furthermore, the amplitude of the harmonic and THD of the proposed structure are compared with other structures. To demonstrate the effectiveness of the proposed method, a sample of 11-level three-phase inverter is designed and is simulated using Simulink toolbox of MATLAB software and the obtained results have been evaluated.