An Interleaved Current-Fed PFC Isolated Converter with Voltage Follower Characteristics

This article presents an interleaved modified flyback converter with pulse frequency modulation (PFM) for power factor correction (PFC) applications. The proposed topology is based on a switching cell (SC) with a four-winding coupled inductor. It presents soft commutation for a wide frequency range, with a current-fed configuration and low input current ripple. The converter has no reverse recovery loss when the diodes block, presents resistive input characteristics, making it a voltage follower, and requires a low component count. These features make the converter suitable for various applications that require an interface between an AC source to feed a DC load. The topology of the converter is analyzed, providing the principle of operation, along with the mathematical characterization and the design description. Finally, the experimental results were obtained for a 300 W application operating at 66 kHz, with an input voltage of 127 V RMS generating an output voltage of 400 V with low ripple. It also presents nearly unit power factor (PF), low zero crossing distortion, and low total harmonic distortion (THD).