DC to DC converter based Asymmetrical multilevel inverter with reduced number of components

In this paper, the variable voltage method has been presented to minimize the components of an asymmetrical multilevel inverter (AMI). AMI consists of one main bridge and many auxiliary bridges to increment the number of levels (NOLs) in the output voltage which minimizes the total harmonic distortion (THD). However, the number of auxiliary bridges increases the space for installation, cost and components. To overcome these drawbacks a buck converter (BC), having low rating compared to the rated value of AMI is attached to the auxiliary bridge. This method gives possibility to obtain the higher NOLs with a reduced number of components of AMI. A comparative study is done with existing AMIs topologies to show the effectiveness of the variable voltage method on the basis of the number of semiconductor switches, a variety of DC sources, number of DC sources, and total standing voltage. In this paper, simulation is performed in the MATLAB/SIMULINK environment. The output voltage and THD have been calculated by simulation of 9-level and 15-level multilevel inverter. The hardware implementation for the 9-level multilevel inverter has been done using a low-cost microcontroller. The simulation results are verified by comparing them with those obtained experimentally.