Simple criteria to evaluate a converter as an active power factor corrector

Limited dynamics of power stages in active power factor correction circuits sets a bound on a degree to which current can be shaped. In this paper, a general approach to evaluate the converter dynamics versus the necessary dynamics for operation as an APFC is introduced. A simple criterion is developed in the time domain that enables characterization of converter topology and component values. Calculations are validated by simulation and experimental results for a boost converter as an example.