Research on interleaved PFC single-stage wide input AC-DC converter

This article presents a single-stage AC-DC converter composed of a Boost converter and an LLC resonant converter. First, the power factor correction (PFC) of the interleaved Boost converter is analyzed. In discontinuous conduction mode (DCM), the expressions for the total input current and the power factor (PF) of the interleaved Boost circuit are derived. The operating range that satisfies a high power factor is determined by analyzing the relationship between the input current, power factor, input voltage, and output voltage. Furthermore, using the fundamental harmonic approximation (FHA) method and time-domain analysis, the gain of the Boost stage and the LLC resonant tank is analyzed, and the resonant tank parameters are designed for the circuit under power balance conditions.