Implementation of digital control strategy for asymmetric cascaded multilevel inverter

The cascaded multilevel inverter (CMLI) has gained much attention in recent years due to its advantages in high voltage and high power with low harmonics applications[1]. A standard cascaded multilevel inverter requires n DC sources for 2n+1 levels at the output, where n is the number of inverter stages. This paper presents a topology to control cascaded multilevel inverter that is implemented with multiple DC sources to get 2n+1 - 1 levels[2]. Without using Pulse Width Modulation (PWM) technique, the firing circuit can be implemented using flip-flop which greatly reduces the Total Harmonic Distortion (THD) and switching losses[3]. To develop the model of a cascaded hybrid multilevel inverter, a simulation is done based on MATLAB/SIMULINK software. Their integration makes the design and analysis of a hybrid multilevel inverter more complete and detailed.

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