Analysis and design of SEPIC converter in boundary conduction mode for universal-line power factor correction applications

Abstract

In this paper, a SEPIC converter operated in boundary conduction mode for power factor correction applications with arbitrary output voltage is proposed, analyzed and designed. By developing an equivalent circuit model for the coupled inductor structure, a SEPIC converter with or without coupled inductors (and ripple current steering) can be analyzed and designed in a unified framework. Power factor correction under boundary conduction operation mode can be achieved conveniently using a simple commercially available control IC. Experimental results are provided to validate the circuit design.