Quasi resonant push-pull converter and control method thereof

摘要

The invention relates to a quasi-resonant push-pull converter and the method for controlling the same, said push-pull converter comprising: a direct current (DC) input power supply configured to supply DC input for the converter; a first power input unit and a second power input unit, connected to said DC input power supply, respectively and configured to supply input for the converter in different periods, comprising a first power switching tube and a second power switching tube, a first primary winding and a second primary winding; a power output circuit, configured to supply output of the converter, comprising secondary windings and full-bridge rectification circuits; a first output capacitor and a second output capacitor connected to said power output circuit and configured to store DC electric energy output by the power output circuit in which a resonant element is arranged to achieve a quasi-resonant switching circuit through voltage feedback; and a switching circuit being controlled through voltage feedback, whereby turns ratio of the primary windings and the secondary windings of the push-pull converter is controlled.

主权项

1. A quasi-resonant push-pull converter comprising:
a transformer having a primary winding and a secondary winding; an input circuit configured to apply a DC power source to the primary winding of the transformer; a resonant circuit; a rectifier circuit having an input coupled to the secondary winding and an output coupled to the resonant circuit; and a switching circuit configured to modify a coupling of the secondary winding to the resonant circuit via the rectifier circuit responsive to a voltage of the DC power source.