Buck converter with magnetic-coupled inductors for power factor corrector

Abstract

The step-down dc-to-dc converter for application in power factor corrector is proposed and analysed in this paper. Unlike a conventional buck converter containing a single inductor and output capacitor, the proposed converter uses two magnetic-coupled inductors and two output capacitors connected in series. The output voltage of such a coupled inductor buck converter is equal to the sum of voltages of these capacitors. The direct interaction of the input voltage occurs only with a part of the output voltage. This allows increasing a conduction angle in the power factor corrector (PFC) on the basis of the proposed converter and, as a result, reducing the total harmonic distortions and increasing a power factor to satisfy current standard requirements. A detailed analysis of the operation of the proposed converter is presented. The reliability of the analysis is confirmed by a small discrepancy between the results of calculation, modeling and experiment.