US 11,750,101 B2
Resonant converter
Weiyin Duan, Guangdong (CN)
Assigned to SHENZHEN HUNTKEY ELECTRIC CO., LTD., Shenzhen (CN)
Appl. No. 17/298,535
Filed by SHENZHEN HUNTKEY ELECTRIC CO., LTD., Guangdong (CN)
PCT Filed Apr. 3, 2020, PCT No. PCT/CN2020/083338
§ 371(c)(1), (2) Date May 28, 2021,
PCT Pub. No. WO2020/207358, PCT Pub. Date Oct. 15, 2020.
Claims priority of application No. 201910276351.8 (CN), filed on Apr. 8, 2019.
Prior Publication US 2022/0029542 A1, Jan. 27, 2022
Int. Cl. H02M 3/335 (2006.01); H02M 1/00 (2006.01)
CPC H02M 3/33507 (2013.01) [H02M 1/0006 (2021.05); H02M 1/0054 (2021.05); H02M 3/33571 (2021.05); H02M 3/33576 (2013.01); H02M 3/33592 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A resonant converter comprising an input terminal, an output terminal, a first switch, a second switch, a third switch, a fourth switch, a frequency controller, a resonant capacitor, a first transformer, a second transformer, a feedback circuit and a synchronous rectification controller; wherein:
the input terminal is connected to an external power supply and the output terminal is connected to an external load;
the first switch and the second switch are connected in series between the input terminal and a ground, and a control terminal of the first switch and a control terminal of the second switch are both connected to the frequency controller; a common terminal connected to the first switch and the second switch is connected to one terminal of resonant capacitor;
a second terminal of the primary side of the first transformer is connected to a first terminal of primary side of the second transformer, and a first terminal of the primary side of the first transformer is connected to the other terminal of the resonant capacitor, a second terminal of the primary side of the second transformer is connected to the ground;
a second terminal of the secondary side of the first transformer is connected in series with the secondary side of the second transformer, and a first terminal of the secondary side of the first transformer is connected to the ground through the third switch; a second terminal of the secondary side of the second transformer is connected to the ground through the fourth switch; a common terminal connected to the secondary side of the first transformer and the secondary side of the second transformer is connected to the output terminal;
the feedback circuit is connected between the output terminal and the frequency controller;
the frequency controller is configured to output a first control signal to control the first switch and a second control signal to control the second switch, based on a feedback signal output by the feedback circuit, so that the first transformer and the second transformer alternately output currents to the secondary side;
a first input terminal of the synchronous rectification controller is connected to the first terminal of the secondary side of the first transformer, and a second input terminal of the synchronous rectification controller is connected to the second terminal of the secondary side of the second transformer;
the synchronous rectification controller is configured to output a fourth control signal to control the fourth switch based on a voltage of the first terminal of the secondary side of the first transformer, and output a third control signal to control the third switch based on a voltage of the second terminal of the secondary side of the second transformer.