Analysis and spectral characteristics of a PWM rectifier with frequency jitter and random pulse width modulation techniques

The acoustic noise spectrum in power electronic system is closely related to the spectrum of the voltage waveform and can be reduced by avoiding the concentration of harmonic energy in distinct tones. Frequency jitter and randomized pulse width modulation are two methods to reduce mechanical vibration and acoustic noise in power electronic. These two techniques can make the harmonic spectrum of inverter output voltage be continuously distributed without affecting the fundamental frequency component. In this paper, Frequency jitter and randomized PWM rectifier and its practical design procedure are presented.