Patents by Inventor Donald P. Cornell

Donald P. Cornell 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).

  • Patent number: 5617308
    Abstract: A resonant link inverter control for driving a multi-phase induction motor through three feed lines each connected to opposite sides of a DC bus by a pair of switches. A resonant tank circuit connects a source of DC voltage through an inductor to the DC bus and provides a tank capacitor in parallel with the DC bus. A bipolar transistor having an anti-parallel diode, which is in series with a clamp capacitor to form a clamp circuit connected across the tank inductance, is turned off in response to the clamp current bearing a predetermined relationship to voltage across the clamp circuit as well as voltage across the DC source. The current in each feed line is sampled in response to clamp current which is just slightly less than that which causes turnoff of the clamp transistor.
    Type: Grant
    Filed: November 10, 1994
    Date of Patent: April 1, 1997
    Assignee: Otis Elevator Company
    Inventors: Andrew P. Weise, Donald P. Cornell