Single-stage AC/DC converter based on sepic topology operating in continuous conduction mode

This paper presents the analysis of a single-phase single-stage switched-mode power supply based on a SEPIC converter operating in continuous conduction mode. The SEPIC converter with bridgeless configuration at the input has the benefit of having fewer semiconductors in conduction in a switching period when compared with the conventional topology. Thus, the overall efficiency is expected to increase. Moreover, the studied topology has high robustness, since to perform the AC-DC conversion with high power factor and high frequency galvanic isolation it uses only two transistors and two diodes. The theoretical analysis, the power stage design and numerical simulation results from a 300 W converter are presented. The converter was designed for a 127 V of input voltage, 200 V of output voltage and switching frequency of 50 kHz.