Pulse width modulation soft-switching control
AssigneeGeneral Motors Corporation
InventorsKeming A. Chen, James F. Lazar, Lateef A. Kajouke
Life of this patent
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Abstract
A DC/DC converter includes a first leg and a second leg. A controller employs hard switching in the first leg to reduce the conduction loss. The controller employs zero voltage in the second leg to reduce the switching loss.
Claims20
A DC/DC converter that converts an input voltage to an output voltage and includes a transformer having a primary side and a secondary side, comprising:
- a primary side bridge rectifier that communicates with the primary side and includes a first leg that is connected across said input voltage and includes a first switching circuit and a second switching circuit, and a second leg that is connected across said input voltage and that includes a third switching circuit and a fourth switching circuit;
- a switch controller that employs zero voltage switching (ZVS) to control said third and fourth switching devices and hard switching to control said first and second switching devices.
A method for operating a DC/DC converter including a primary side bridge rectifier with a first leg that is connected across said input voltage and includes a first switching circuit and a second switching circuit, and a second leg that is connected across said input voltage and that includes a third switching circuit and a fourth switching circuit, comprising:
- during an first half cycle:
- turning on said first switching circuit on with hard switching;
- turning off said fourth switching device with zero voltage switching (ZVS);
- turning said third switching circuit on with said ZVS;
- and
- turning said first switching circuit off with hard switching.
A DC/DC converter comprising:
- a first leg;
- a second leg;
- and
- a controller that employs hard switching in the first leg to reduce conduction loss and zero voltage in the second leg to reduce switching loss.
Dependencies are inferred from the claim text.