Patents by Inventor David S. Wardrop

David S. Wardrop 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).

  • Fuel cell system shunt regulator method and apparatus
    Patent number: 7132185
    Abstract: A fuel cell system for powering a work load includes a fuel cell stack and a shunt regulator having a threshold detection; transistorized power switching element, and a dump load. The threshold detection element identifies when an abnormally high voltage rises. The power switching element routes power from the high voltage buss to the dump load. The dump load acts as an electrical energy sink, and may provide dissipated energy to the fuel cell stack in the form of heat. The switching element can also shunt power to the dump load when a digital control signal is set, for example at startup or during cold start conditions.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: November 7, 2006
    Assignee: Ballard Power Systems Inc.
    Inventors: David S. Wardrop, Michael Sexsmith, Russell H. Barton
  • Fuel cell system shunt regulator method and apparatus
    Publication number: 20030113600
    Abstract: A fuel cell system for powering a work load includes a fuel cell stack and a shunt regulator having a threshold detection; transistorized power switching element, and a dump load. The threshold detection element identifies when an abnormally high voltage rises. The power switching element routes power from the high voltage buss to the dump load. The dump load acts as an electrical energy sink, and may provide dissipated energy to the fuel cell stack in the form of heat. The switching element can also shunt power to the dump load when a digital control signal is set, for example at startup or during cold start conditions.
    Type: Application
    Filed: December 14, 2001
    Publication date: June 19, 2003
    Applicant: Ballard Power Systems Inc.
    Inventors: David S. Wardrop, Michael Sexsmith, Russell H. Barton