Method of double averaging for modeling PFC switching converters

This paper describes the modeling of power-factor-correction converters under average-current-mode control. The approach employs a double averaging procedure, which first applies the usual averaging over the switching period and subsequently applies averaging over the mains period. The resulting model, after two averaging steps, is nonlinear and capable of describing the low-frequency nonlinear dynamics of the system. The parameter ranges within which stable operation is guaranteed can be accurately and easily found using this model.