Patents by Inventor Muchao XIANG

Muchao XIANG 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).

  • Operating method of full-bridge modular multilevel converter boosting AC voltages for high voltage direct current transmission
    Patent number: 9735702
    Abstract: Provided is an operating method of a full-bridge sub-module (FBSM)-based modular multilevel converter for HVDC transmission with AC-side voltage boosting. The peak value of the AC-side voltage is increased under a constant DC-link voltage by using FBSM's negative output voltage under steady state, wherein keeping the semiconductor's current rating constant during AC-side voltage boosting is in favor of reducing converter cost by decreasing energy interaction between the upper and lower arms in a leg, and further capacitance value of FBSM's capacitor under a constant capacitor voltage ripple, keeping the RMS value of AC-side current constant during AC-side voltage boosting can effectively improve transmission capacity of the converter while reducing converter cost, and keeping converter transmission capacity constant during AC-side voltage boosting can reduce RMS value of arm currents while reducing converter cost, thereby reducing power loss of FBSMs and improving converter efficiency.
    Type: Grant
    Filed: March 8, 2016
    Date of Patent: August 15, 2017
    Assignee: Huazhong University of Science and Technology
    Inventors: Jiabing Hu, Maozeng Lu, Muchao Xiang, Lei Lin
  • OPERATING METHOD OF FULL-BRIDGE MODULAR MULTILEVEL CONVERTER BOOSTING AC VOLTAGES
    Publication number: 20170170660
    Abstract: Provided is an operating method of a full-bridge sub-module (FBSM)-based modular multilevel converter for HVDC transmission with AC-side voltage boosting. The peak value of the AC-side voltage is increased under a constant DC-link voltage by using FBSM's negative output voltage under steady state, wherein keeping the semiconductor's current rating constant during AC-side voltage boosting is in favor of reducing converter cost by decreasing energy interaction between the upper and lower arms in a leg, and further capacitance value of FBSM's capacitor under a constant capacitor voltage ripple, keeping the RMS value of AC-side current constant during AC-side voltage boosting can effectively improve transmission capacity of the converter while reducing converter cost, and keeping converter transmission capacity constant during AC-side voltage boosting can reduce RMS value of arm currents while reducing converter cost, thereby reducing power loss of FBSMs and improving converter efficiency.
    Type: Application
    Filed: March 8, 2016
    Publication date: June 15, 2017
    Inventors: Jiabing HU, Maozeng LU, Muchao XIANG, Lei LIN