Patents by Inventor Liang-Jun Ji

Liang-Jun Ji 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).

  • Uninterruptible power supplies
    Patent number: 7307360
    Abstract: Uninterruptible power supplies (UPSs) are generally discussed herein with particular discussions extended to fuel-cell-based UPSs used in conjunction with DC power supplies for improved operating efficiencies. With a wide voltage DC power supply, a DC-AC inverter may be omitted from the UPS and power from a back up power source, such as a battery or a fuel cell, may be applied directly to the DC power supply without performing two power conversions. The end result is a more efficient system capable of longer operating time.
    Type: Grant
    Filed: January 31, 2005
    Date of Patent: December 11, 2007
    Assignee: Arizona Board of Regents
    Inventors: James Gonzales, Govindasamy Tamizhmani, Bradley Rogers, Liang-Jun Ji
  • Uninterruptible power supplies
    Publication number: 20060006739
    Abstract: Uninterruptible power supplies (UPSs) are generally discussed herein with particular discussions extended to fuel-cell-based UPSs used in conjunction with DC power supplies for improved operating efficiencies. With a wide voltage DC power supply, a DC-AC inverter may be omitted from the UPS and power from a back up power source, such as a battery or a fuel cell, may be applied directly to the DC power supply without performing two power conversions. The end result is a more efficient system capable of longer operating time.
    Type: Application
    Filed: January 31, 2005
    Publication date: January 12, 2006
    Inventors: James Gonzales, Govindasamy Tamizhmani, Bradley Rogers, Liang-Jun Ji