Analysis and improvement on input current of one-cycle controlled PFC converter

The influence on input current harmonics by single-edge modulation of conventional one-cycle control (OCC) in single-phase PFC converters is analyzed. The relation between low-frequency odd harmonics of the inductor current and modulation scheme is revealed. Based on the analysis, bi-edge modulation with triangular-wave as carrier is proposed. The inductor current is modulated both at leading- and trailing-edge in a switching cycle. Consequently, the low-frequency odd harmonics of inductor current is reduced, and the quality of the input current is improved. The validity of the theoretical analysis and feasibility of the bi-edge modulation OCC scheme are verified by simulation and experiment results.