| CPC H02M 1/4233 (2013.01) [H02M 1/0012 (2021.05); H02M 1/081 (2013.01)] | 8 Claims |

|
1. A totem-pole PFC (power factor correction) circuit, comprising:
an AC power source;
a first bridge arm, comprising a first switch and a second switch electrically connected in series, wherein a connection node between the first switch and the second switch is electrically connected to a first terminal of the AC power source;
a second bridge arm, comprising a third switch and a fourth switch electrically connected in series, wherein a connection node between the third switch and the fourth switch is electrically connected to a second terminal of the AC power source; and
a controller, configured to control operation of the first to fourth switches,
wherein the controller detects a first voltage of the first terminal of the AC power source, when a potential at the first terminal is higher than a potential at the second terminal, the controller turns off the fourth switch if the first voltage is lower than a first threshold voltage, and when the potential at the first terminal is lower than the potential at the second terminal, the controller turns off the third switch if the first voltage is higher than a second threshold voltage,
wherein when the potential at the first terminal is higher than the potential at the second terminal, the controller turns on the fourth switch if the first voltage is higher than the first threshold voltage, and when the potential at the first terminal is lower than the potential at the second terminal, the controller turns on the third switch if the first voltage is lower than the second threshold voltage.
|