Now showing items 1-6 of 6

    • Multi-loop control for quasi-resonant converters 

      Virginia Tech Intellectual Properties, Inc.; Lee, Fred C.; Ridley, Raymond B. (United States Patent and Trademark Office, 1989-09-12)
      A multi-loop controller for controlling a quasi-resonant converter having a power switch, a filter inductor and an output voltage. The controller includes a sensor circuit for sensing the output voltage of the converter. ...
    • Quasi-parallel voltage regulator 

      Virginia Tech Intellectual Properties, Inc.; Lee, Fred C.; Xu, Ming Gang; Liu, Ya; Sun, Ju-Lu (United States Patent and Trademark Office, 2011-01-18)
      Improved regulation and transient response are provided by a power supply architecture providing both unregulated and regulated voltage converters in parallel but deriving input power from separate power supplies connected ...
    • Quasi-resonant DC-DC converters with reduced body diode loss 

      Virginia Tech Intellectual Properties, Inc.; Lee, Fred C.; Xu, Ming Gang (United States Patent and Trademark Office, 2006-01-24)
      Buck converters having a resonant inductor Lr, resonant capacitor Cr, and synchronous switch Q3 that together provide reduced switching loss and soft switching. In operation, the resonant inductor Lr is charged during a ...
    • Soft-switching PWM converters 

      Center for Innovative Technology; Virginia Polytechnic Institute and State University; Virginia Tech Intellectual Properties, Inc.; Lee, Fred C.; Hua, Guichao C. (United States Patent and Trademark Office, 1995-08-15)
      A full-bridge zero-voltage-switching pulse-width-modulated converter employs a saturable reactor in place of the linear inductor in order to reduce current stress on the active switches, reduce voltage stress on the rectifier ...
    • Two-stage single phase bi-directional PWM power converter with DC link capacitor reduction 

      Virginia Tech Intellectual Properties, Inc.; Wang, Ruxi; Wang, Fred; Boroyevich, Dushan; Dong, Dong (United States Patent and Trademark Office, 2015-06-30)
      DC link capacitance in a bi-directional AC/DC power converter using a full-bridge or H-bridge switching circuit can be greatly reduced and the power density of the power converter correspondingly increased by inclusion of ...
    • Zero-current transition PWM converters 

      Center for Innovative Technology; Intellectual Properties | Kft; Virginia Polytechnic Institute and State University; Lee, Fred C.; Hua, Guichao C. (United States Patent and Trademark Office, 1996-01-23)
      A zero-current transition pulse-width modulated (ZCT-PWM) d.c.-d.c. converter allows minority-carrier semiconductor devices such as, for example, bipolar junction transistors (BJTs), insulated gate bipolar transistors ...