Patents by Inventor Steffen Doenitz

Steffen Doenitz 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 exhaust system
    Patent number: 7878298
    Abstract: One embodiment of the invention includes a product including a fuel-cell exhaust diffuser; an air funnel; and at least two exhaust tubes attached to the diffuser.
    Type: Grant
    Filed: December 18, 2006
    Date of Patent: February 1, 2011
    Assignee: GM Global Technology Operations LLC
    Inventors: Franz Winter, Wolfgang Heil, Steffen Doenitz, Michael J. Gorman
  • Method for detection and diagnosis of isolation faults in fuel cell hybrid vehicles
    Patent number: 7862944
    Abstract: An isolation fault detection system for detecting isolation faults in a fuel cell system associated with a fuel cell hybrid vehicle. The isolation fault detection system measures a stack voltage potential, a positive fuel cell voltage potential, a negative fuel cell voltage potential, a positive battery voltage potential, and an overall battery voltage potential. The isolation fault detection system then uses these voltage potentials in mesh equations to compare the measured voltage potentials to voltage potentials that would occur during a loss of isolation. In one embodiment, the isolation fault detection system uses these five measured voltage potentials to determine whether an isolation fault has occurred at four separate locations in the fuel cell hybrid vehicle. The system also can detect the location of the isolation fault.
    Type: Grant
    Filed: July 13, 2005
    Date of Patent: January 4, 2011
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Hartmut Hinz, Steffen Doenitz
  • FUEL-CELL EXHAUST SYSTEM
    Publication number: 20080141667
    Abstract: One embodiment of the invention includes a product including a fuel-cell exhaust diffuser; an air funnel; and at least two exhaust tubes attached to the diffuser.
    Type: Application
    Filed: December 18, 2006
    Publication date: June 19, 2008
    Applicant: GM Global Technology Operations, Inc.
    Inventors: Franz Winter, Wolfgang Heil, Steffen Doenitz, Michael J. Gorman
  • Method for detection and diagnosis of isolation faults in fuel cell hybrid vehicles
    Publication number: 20070013382
    Abstract: An isolation fault detection system for detecting isolation faults in a fuel cell system associated with a fuel cell hybrid vehicle. The isolation fault detection system measures a stack voltage potential, a positive fuel cell voltage potential, a negative fuel cell voltage potential, a positive battery voltage potential, and an overall battery voltage potential. The isolation fault detection system then uses these voltage potentials in mesh equations to compare the measured voltage potentials to voltage potentials that would occur during a loss of isolation. In one embodiment, the isolation fault detection system uses these five measured voltage potentials to determine whether an isolation fault has occurred at four separate locations in the fuel cell hybrid vehicle. The system also can detect the location of the isolation fault.
    Type: Application
    Filed: July 13, 2005
    Publication date: January 18, 2007
    Inventors: Hartmut Hinz, Steffen Doenitz