BRIDGELESS BUCK ACTIVE POWER FACTOR CORRECTION (APFC) CIRCUIT

摘要

A bridgeless voltage step-down Active Power Factor Correction (APFC) circuit comprises a controller, a first switch (T1), a second switch (T2), a first diode (D1), a second diode (D2), a first inductor (L1), a second inductor (L2), a capacitor (C) and a load (R). A first BUCK circuit consists of the first switch, the first diode and the first inductor. A second BUCK circuit consists of the second switch, the second diode and the second inductor. By adopting the double BUCK circuit with step-down voltage, single-stage Power Factor Correction (PFC) and a voltage step-down function are achieved and the low voltage direct-current power supply is output. The bridgeless voltage step-down APFC is applied to an Alternating Current-Direct Current (AC-DC) conversion low-voltage direct-current power supply, the stage number of the circuit can be simplified, and the cost and the volume can be reduced.