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In this paper, three novel multicarrier pulse width modulation techniques which uses stepped carrier waveform, unipolar sine carrier waveform and staircase carrier waveforms are proposed for seven-level and nine-level cascaded inverter. In each carrier waveform different techniques such as phase disposition (PD), inverted phase disposition (IPD), phase opposition disposition (POD) and alternative phase opposition disposition (APOD) are implemented. The fundamental output voltage and harmonics obtained in each method are compared with the output waveform obtained with the triangular carrier waveform. The proposed switching technique enhances the fundamental component of the output voltage and improves total harmonic distortion. The different PWM methodologies adopting the constant switching frequency multicarrier with different modulation indexes are simulated for a 1 kW, 3φ inverter using MATLAB/SIMULINK and the results are verified. The effect of switching frequency on the fundamental output voltage and harmonics are also analyzed. Copyright© 2013 Praise Worthy Prize Srl-All rights reserved.