Comparative Analysis of Cascaded Half Bridge Inverter Using Different Modulation Techniques

The multilevel inverters have gained very great interest in the power industry. It is easy to generate high power with medium voltage switches multilevel structure in which the voltage stresses of the devices can be controlled. Increase of the number of voltage levels in inverter without the increase in the rating of the switches increases the power rating and reduces the harmonic distortion. It enables to reach high voltages with low harmonic distortion without the use of transformers. Different modulation techniques such as phase disposition (PD), phase opposition disposition (POD), alternate phase opposition disposition (APOD) techniques are used to generate the pulse pattern for the inverter. In this paper, a five level and twenty one level cascaded half bridge multilevel inverter are simulated in MATLAB/Simulink and the harmonic analysis has been carried out.