EMI suppression in a Buck converter based on chaotic Gaussian switching waveform technique

With the extensive use of wide bandgap represented by silicon carbide (SiC) and gallium nitride (GaN) semiconductor devices, The power density of power electronic converters has been enhanced, driving towards miniaturization and integration, which has led to a more intricate electromagnetic environment within power converters, and the accompanying electromagnetic interference (EMI) problem has become more prominent. Generally, the voltage and current mutation caused by the rapid switching action of power semiconductor devices is regarded as the primary source of EMI in power converters. To mitigate the conducted EMI from power converters, this study employed an infinitely differentiable "S"-shaped Gaussian function and chaotic pulse width modulation (CPWM) signals for convolution, yielding an optimized chaotic gaussian pulse width modulation (CGPWM) signal that served as a reference waveform to shape the switching voltage waveform of the power metal-oxide-semiconductor field-effect transistors (MOSFETs). Experimental results demonstrate the efficacy of this driving waveform in suppressing EMI generated by power converters.