Totem-Pole Boost Bridgeless PFC Rectifier With Simple Zero-Current Detection and Full-Range ZVS Operating at the Boundary of DCM/CCM

A totem-pole boost bridgeless power-factor-correction rectifier with simple zero-current detection and full-range zero-voltage switching (ZVS) is proposed, which operates at the boundary of discontinuous-conduction mode and continuous-conduction mode. Comparing with the boundary dual boost bridgeless rectifier, the required number of power components is reduced by one third and two current transducers can be eliminated. The zero-current detection is achieved by sampling the diode current through a single current transducer. Besides, a soft-transition method is proposed to suppress the current spike at the line-voltage zero-crossing point. Furthermore, a ZVS range extension operation is proposed to achieve ZVS in the MOSFETs within the full range of line input, which needs no additional MOSFETs. This also makes it possible to reduce MOSFET turn-OFF losses by paralleling external capacitors. Hence, a high-efficiency and low common-mode noise-interference bridgeless rectifier is achieved. This rectifier is also a candidate for interleaving operation to upgrade the power level. The experimental results show that ZVS is achieved within the full range of universal line input. The efficiency is above 96% at full load under 90 V and the maximum efficiency is above 98.4%. The ZVS range extension operation improves the efficiency by 0.5%.