DC/DC converter, power converter and control method thereof

摘要

A DC/DC converter, a power converter and a control method thereof are disclosed, where the DC/DC converter includes an output circuit having a load, a rectangular wave generator having a bridge arm, a resonant tank, a detection unit and a control unit. The bridge arm includes a first and a second switches connected each other. The detection unit detects a signal related to a state of the load. When the state of the load is a light-load or a no-load, the control unit controls ON/OFF state of the first and second switches by pulse width modulation mode to convert an input voltage into at least one rectangular wave for the resonant tank. A duty ratio of the first switch is within a first or second predetermined range, and a duty ratio of the second switch is complementary to the duty ratio of the first switch, whereby a voltage gain of the DC/DC converter is greater than 1.

主权项

1. A DC/DC converter comprising:
an output circuit having a load; a resonant tank electrically coupled with the output circuit; a rectangular wave generator electrically coupled with the resonant tank, the rectangular wave generator having at least one bridge arm including a first switch and a second switch coupled to each other; a detection unit for detecting a signal related to a state of the load; and a control unit for controlling a ON/OFF state of the first and second switches by a pulse width modulation mode to convert an input voltage into at least one rectangular wave for the resonant tank when the state of the load is a light-load or a no-load, wherein when the state of the load is a light-load or a no-load, the control unit controls a duty ratio of the first switch to be within a first or second predetermined range and a duty ratio of the second switch to be complementary to the duty ratio of the first switch, wherein the first or second predetermined range is configured to set a voltage gain of the DC/DC converter to be greater than 1.