Patent ID: 11929669
Assignee: INVENTCHIP TECHNOLOGY CO., LTD.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  G  Y | IPC G  H

Claim 3:
4. The totem-pole bridgeless power factor correction device of claim 1, wherein the control module is configured to:
generate a zeroth control signal in the first time period to control the third transistor and the fourth transistor to be off;
perform a zero-crossing detection on the AC voltage in the first time period;
generate a first control signal before the AC voltage crosses zero to control a conduction state of the first transistor and the second transistor;
after the AC voltage crosses zero, generate a second control signal to control the conduction state of the first transistor and the second transistor, and wherein the first control signal and the second control signal are configured such that:
the first transistor and the second transistor are turned off before the AC voltage crosses zero; and
one of the first transistor and the second transistor is configured to be turned off after the AC voltage crosses zero, and the other of the first transistor and the second transistor is configured to be turned on and off at the targeted switching frequency, and wherein a turn-on duty cycle of the other of the first transistor and the second transistor gradually increases; and

after the first time period, generate a third control signal to control the first transistor and the second transistor to switch at a first frequency, and control the third transistor and the fourth transistor to switch at a second frequency, and wherein the targeted switching frequency is greater than the first frequency, and the first frequency is greater than the second frequency.