నైరూప్య

Comparative study of THD in Asymmetrical Cascaded H-Bridge Multilevel Inverter in different levels

M.S.Sivagamasundari,Dr.P.Melba Mary

Cascaded H-Bridge multilevel inverter is a promising topology and built to synthesize a desired ac voltage from several levels of dc voltages with better harmonic spectrum and are suitable for high voltage and high power applications. A small total harmonic distortion is the most important feature of these inverters. This paper compares the total harmonic distortion in 5, 7, 9 and 11 levels of Asymmetrical Cascaded H-Bridge Multilevel inverter employing multicarrier pulse width modulation control technique. Multicarrier pulse width modulation control technique is adopted in the firing circuit to provide an acceptable control in the inverter output voltage. Hence we could achieve the improved efficiency of the system . The analysis has been simulated using MATLAB/SIMULINK. The simulated output shows very favorable result.