Patent ID: 11870342
Assignee: DELTA ELECTRONICS (SHANGHAI) CO., LTD.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 27:
28. A resonant converter, comprising:
a primary circuit coupled to an input power supply, and the primary circuit comprising a plurality of primary switches;
a transformer having a primary winding and a secondary winding;
a resonant network coupled between the primary circuit and the primary winding;
a secondary circuit coupled to the secondary winding, and the secondary circuit comprising a plurality of secondary switches; and
a control circuit coupled to the primary circuit and the secondary circuit, and configured to control the plurality of primary switches operating with a switching frequency, wherein at least one of the plurality of primary switches is configured to be turned on from a first switching moment until a second switching moment,
wherein when the switching frequency is greater than a preset switching frequency, the control circuit is configured to control the plurality of secondary switches operating in a normal state, and
when the switching frequency is lesser than or equal to the preset switching frequency, the control circuit is configured to control at least one of the plurality of secondary switches to be turned on during a first time interval, such that the secondary winding being clamped by a preset voltage, a current of the resonant network is increased in a first flowing direction, and an output current is increased in a second flowing direction or equal to zero, wherein the first time interval is between the first switching moment and the second switching moment,
wherein the first time interval is determined by a third switching moment and the second switching moment,
the at least one of the plurality of primary switches is turned on from the third switching moment until the second switching moment and is turned off at the second switching moment, and
the at least one of the plurality of secondary switches is turned on from the third switching moment until the second switching moment.