SPICE-based tools typically perform AC analysis in the time domain which requires the converter to be converted to an average model. This approach excludes all but the most simple converter topologies and control methods. Although it is useful for undamped LC frequency responses, these aren’t complex switching converters.
PSIM and DSIM can perform an AC sweep to determine the frequency response of a converter in the time domain. We then extract the gain and phase information of the signal of reference vs. the injected perturbation.
In this webinar, we cover how to set up these sweeps for various converter types and control techniques.