Asymmetric Multi-Level Inverter

Abstract

This paper proposes a multi-level inverter (MLI) which has two or more unequal DC voltage source with lesser number of components. The proposed MLI composed of many basic DC source units, where each basic DC source unit are stacked in series to get higher voltage levels. The proposed topology of MLI is derived from a basic MLI cascaded H-bridge inverter. The designed AMLI is capable of handling negative current and hence capable of operating in all 4 quadrants due to absence of components like diode which is seen in the proposed topology, the phase opposition disposition PWM technique is used to trigger the switches. By utilizing three different DC voltage source as input to AMLI, we get an output waveform in staircase form of 15 level. The THD of output staircase waveform is 8.25% in which it has majority of higher harmonics distortion, by using LCL filter the THD of 0.1% can be achieved. The work is carried out on MATLAB / SIMULINK 2020Ra.