Patent ID: 9660543
Date: 2017-05-23
CPC Classifications: H02M,Y02B

Claim:
1. An electric power conversion circuit system comprising: a primary side conversion circuit comprising a left arm and a right arm between a primary side positive bus and a primary side negative bus, wherein said left arm and said right arm are respectively composed of two switching transistors connected in series, and a primary side winding of a transformer is connected to between a connecting point of the two switching transistors of said left arm and a connecting point of the two switching transistors of said right arm; a secondary side conversion circuit comprising a left arm and a right arm between a secondary side positive bus and a secondary side negative bus, wherein said left arm and said right arm are respectively composed of two switching transistors connected in series, and a secondary side winding of said transformer is connected to between a connecting point of the two switching transistors of said left arm and a connecting point of the two switching transistors of said right arm; and a control circuit for controlling switching of said switching transistors of said primary side conversion circuit and said secondary side conversion circuit; wherein said control circuit controls, when an output voltage is at a relatively light loading, changing of a duty of a transmitting side among said primary side conversion circuit and said secondary side conversion circuit, and changing of a half-bridge phase difference of said left arm and said right arm of said primary side conversion circuit and said secondary side conversion circuit.