Patents by Inventor Zu-Cheng LIU

Zu-Cheng 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).

  • Uninterruptible power system with backfeed detection and method of operating the same
    Patent number: 9431853
    Abstract: An uninterruptible power system and a method of operating the same are disclosed. The uninterruptible power system includes a power conversion apparatus, a switch unit, a first voltage detection unit, a second voltage detection unit, and a comparison unit. The power conversion apparatus receives an AC power source and converts the AC power source to supply an AC load. The first voltage detection unit detects an input voltage of the power conversion apparatus and produces a first voltage signal. The second voltage detection unit detects an output voltage of the switch unit and produces a second voltage signal. Under the AC power source is disabled and the power conversion apparatus provides a backup power to supply the AC load, the switch unit is detected in a fault operation when the first voltage signal is compared by the comparison unit to equal to the second voltage signal.
    Type: Grant
    Filed: July 12, 2013
    Date of Patent: August 30, 2016
    Assignee: DELTA ELECTRONICS, INC.
    Inventors: Sung-Chieh Yeh, Wei-Guo Shen, Hui Zhou, Zu-Cheng Liu
  • UNINTERRUPTIBLE POWER SYSTEM AND METHOD OF OPERATING THE SAME
    Publication number: 20140183958
    Abstract: An uninterruptible power system and a method of operating the same are disclosed. The uninterruptible power system includes a power conversion apparatus, a switch unit, a first voltage detection unit, a second voltage detection unit, and a comparison unit. The power conversion apparatus receives an AC power source and converts the AC power source to supply an AC load. The first voltage detection unit detects an input voltage of the power conversion apparatus and produces a first voltage signal. The second voltage detection unit detects an output voltage of the switch unit and produces a second voltage signal. Under the AC power source is disabled and the power conversion apparatus provides a backup power to supply the AC load, the switch unit is detected in a fault operation when the first voltage signal is compared by the comparison unit to equal to the second voltage signal.
    Type: Application
    Filed: July 12, 2013
    Publication date: July 3, 2014
    Inventors: Sung-Chieh YEH, Wei-Guo SHEN, Hui ZHOU, Zu-Cheng LIU