BRIDGELESS POWER FACTOR CORRECTION CIRCUIT

摘要

A bridgeless PFC circuit is provided. A low-frequency bridge leg includes a first diode and a second diode connected in series; a three-port network includes a switch tube and an inductor; a lightning and surge protection bridge leg includes a third diode and a fourth diode connected in series; a capacitor is connected between terminals of the low-frequency bridge leg, and between terminals of the lightning and surge protection bridge leg; a common terminal of the first and second diodes is connected to a terminal of an AC power, and a common terminal of the third and fourth diodes is connected to the other terminal; and the three-port network has two ports with the capacitor connected therebetween, and another port connected to the common terminal of the third and fourth diodes. Thus, EMI performance and efficiency can be improved and costs of the whole circuit can be lowered.