Patents by Inventor Changrong Liu

Changrong Liu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Multiphase soft switched DC/DC converter and active control technique for fuel cell ripple current elimination
    Patent number: 7518886
    Abstract: DC/DC converter has a transformer having primary coils connected to an input side and secondary coils connected to an output side. Each primary coil connects a full-bridge circuit comprising two switches on two legs, the primary coil being connected between the switches on each leg, each full-bridge circuit being connected in parallel wherein each leg is disposed parallel to one another, and the secondary coils connected to a rectifying circuit. An outer loop control circuit that reduces ripple in a voltage reference has a first resistor connected in series with a second resistor connected in series with a first capacitor which are connected in parallel with a second capacitor. An inner loop control circuit that reduces ripple in a current reference has a third resistor connected in series with a fourth resistor connected in series with a third capacitor which are connected in parallel with a fourth capacitor.
    Type: Grant
    Filed: October 13, 2005
    Date of Patent: April 14, 2009
    Assignee: Virginia Tech Intellectual Properties, Inc.
    Inventors: Jih-Sheng Lai, Changrong Liu, Amy Ridenour