Patents by Inventor Youdong He

Youdong He 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).

  • Variable frequency drive circuit with overvoltage protection
    Patent number: 10355585
    Abstract: A variable frequency drive (VFD) circuit includes an input connectable to an AC source, a rectifier to convert an AC power input to a DC power, a DC link to receive DC power from the rectifier and having a DC link voltage thereon, a DC link capacitor bank with one or more capacitors connected to the DC link, and a pre-charge circuit coupled to the DC link capacitor. The pre-charge circuit further includes one or more resistors, one or more pre-charge relays each operable in on and off states to selectively control a current flow through the resistor(s) so as to control an initial pre-charge of the DC link capacitor, and an overvoltage relay operable in on and off states to selectively cut-off a current flow to the DC link capacitor bank, so as to prevent an overvoltage condition in the DC link capacitor bank.
    Type: Grant
    Filed: March 12, 2015
    Date of Patent: July 16, 2019
    Assignee: Eaton Intelligent Power Limited
    Inventors: Huaqiang Li, Youdong He, Xiaoling Li
  • VARIABLE FREQUENCY DRIVE CIRCUIT WITH OVERVOLTAGE PROTECTION
    Publication number: 20160268797
    Abstract: A variable frequency drive (VFD) circuit includes an input connectable to an AC source, a rectifier to convert an AC power input to a DC power, a DC link to receive DC power from the rectifier and having a DC link voltage thereon, a DC link capacitor bank with one or more capacitors connected to the DC link, and a pre-charge circuit coupled to the DC link capacitor. The pre-charge circuit further includes one or more resistors, one or more pre-charge relays each operable in on and off states to selectively control a current flow through the resistor(s) so as to control an initial pre-charge of the DC link capacitor, and an overvoltage relay operable in on and off states to selectively cut-off a current flow to the DC link capacitor bank, so as to prevent an overvoltage condition in the DC link capacitor bank.
    Type: Application
    Filed: March 12, 2015
    Publication date: September 15, 2016
    Inventors: Huaqiang Li, Youdong He, Xiaoling Li