2.1 Digitally Controlled High Efficiency and High Power Density PFC Circuits - Part 1

In recent years, more attention is focused on increasing power conversion efficiency and power density for universal input power factor correction (PFC) converters while maintaining high power factor (PF) and low input current total harmonic distortions (THD). This necessitates improved bridgeless high frequency PFC topology with zero voltage switching while operating in continuous conduction mode (CCM) or transition mode (TRM). Also the emergence of wide bandgap GaN devices makes such requirement implementable. TI C2000 MCU, with its latest DPWM module and integrated analog peripherals, are uniquely positioned to implement efficient digital control of such power converters. This presentation will introduce two bridgeless PFC designs using C2000 MCU. TI high voltage GaN is used to implement a 3.3kW interleaved CCM totem-pole PFC and a 1.6kW interleaved TRM totem-pole PFC designs. Detailed design considerations are provided to minimize switching loss, current crossover distortion, input current THD and improve efficiency and PF.