Modeling of the power spectrum density of an entirely randomized modulation in power converters

In this paper, the power spectrum density theoretical model of an entirely random modulation signal function, that means random carrier with random pulse position technique, is established. The entirely random switching signal can spread electromagnetic energy concentrated in modulation carrier frequency and is more effective suppression conduction EMI than one simple variable random modulation technique formerly in power electronics. The spectral estimation method is consistent with the model calculation results. The effects of random range for two random variables are discussed.