Performance evaluation of five PWM modulation strategies applied to spread the power spectrum of the power converters

Electromagnetic interference (EMI) resulting from the process of energy conversion using switching power converters, can adversely affect the performance of other neighbor electronic systems, health of human beings, but not only that. Normally EMI can be reduced by adding bulky filters to reduce the conducted EMI, by shielding for radiated EMI, by installing snubber circuits or by other methods. Some of these methods have the unwanted effect of decreasing efficiency of power converter. At the same time, the cost and the physical dimensions of the converters increase, especially if large values are used for the coils and capacitors of the input filter. Another technique to reduce EMI is to use the Spread Spectrum Power Converter (SSPC) that uses the Spread Spectrum Frequency Modulation (SSFM) technique for PWM command. This paper aims to evaluate the performance of spreading the SSPC power spectrum using five SSFM PWM command techniques.