Power Quality Enhancement of Cascaded H Bridge 5 Level and 7 Level Inverters

Multilevel inverters are capable of attaining a staircase output voltage waveform with reduced harmonic content. In this paper, cascaded H bridge 5 level and 7 level inverters are simulated in MATLAB/SIMULINK. The power quality analysis has been carried out for both the designs with and without filters. Filters used at the output of the inverters are low pass filters and second order filters. The amount of deviation of output waveforms from the pure sinusoidal waveforms has been measured as total harmonic distortion. Comparison of both the inverter topologies with and without filters has been done on the basis of Total Harmonic Distortion (THD).