Random Sinusoidal PWM for Three Phase Inverter Using ATMega2560

The Random sinusoidal pulse width modulation (RSPWM) is a non-conventional spread spectrum technique. It is proposed for the suppression of EMI and the improvement of power quality in a three-phase power inverter. This paper propose a digital modulation technique. It is implemented through a compact low-cost microcontroller ATMEGA2560 by developing suitable C coding for producing the required switching pulses for the inverter. A comparative analysis is also presented between the proposed random sinusoidal PWM modulation RSPWM and the conventional SPWM. It is shown that the implementation of RSPWM results in reduced EMI, a decreased Total Harmonic Distortion THD, and the noise effect is also improved significantly.