Performance Evaluation and Analysis of a Combined Quasi-Two-Stage Bridgeless PFC Converter

A combined quasi-two-stage bridgeless power factor correction (BPFC) converter is analyzed and evaluated in this paper. The combined converter is composed of a three-port BPFC (TP-BPFC) converter and a Buck DC-DC converter. A low voltage and high voltage DC voltage ports are provided by the TP-BPFC converter. A low voltage DC load, whose voltage is lower than the peak AC line voltage, can be directly connected to the low voltage DC port of the TP-BPFC converter. Therefore, single-stage power conversion between a low voltage DC load and an AC input can be realized. With the combined BPFC converter, power factor correction, voltage balancing between the low and high voltage ports, and load voltage regulation within a wide range can be realized, simultaneously. High conversion efficiency can be ensured by the reduced conversion stage and low conduction losses of the BPFC converter. The operation principles and characteristics of the combined BPFC converter are analyzed and evaluated with both simulation and experimental results.