Design Optimization of a Phase Shedding Two-phase Interleaved Transition Mode PFC Converter Compliant to Class A EMI Limits

This study covers the design, construction and testing of a 350W two-phase interleaved PFC converter compliant to Class A EMI limits. The used of FAN9611 ASIC allows the cross-coupled master-slave control of the two parallel-connected, interleaved boost converters operating in transition mode for lower current ripple and more manageable stress on the components at higher power applications due to load sharing, and maintains high efficiency and power factor at light load condition due to phase shedding. Tests done with the prototype have shown regulation, efficiency, power factor, and stability that are within the set requirements. Furthermore, the converter has been confirmed to be compliant to Class A limit of EN61000-3-2 for Harmonic Current Emission, and Class A limit of EN55032 for Conducted EMI and Radiated EMI emission standard.