Comparative Analysis of Random PWM Techniques for Cascaded H-Bridge Multi-Level Inverters

Pseudo-random PWM technique is a unique approach to overcome various cons (Discrete frequency harmonics, EMI problems, switching losses, acoustic noise etc.) of conventional PWM techniques. The aim of this scheme is to suppress the magnitude of dominant harmonics in order to overcome the above disadvantages which are due to the high magnitude of the dominant harmonics. In the proposed scheme, a random carrier has been generated using a PN sequence generator and a non-sinusoidal reference has been also analyzed. Different combinations of carriers and references have been considered and their respective performance has been compared.