Patents by Inventor James Douglas Alexander Chambers

James Douglas Alexander Chambers 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).

  • Deriving values of parameters in electrical machines
    Patent number: 8121819
    Abstract: An electrical drive system includes an electrical machine controlled by an electronic controller and requires control signals representing quantities associated with the operation of the electrical machine. These signals may represent, for example, rotor position and flux or current. A controller includes an estimation routine to use the known magnetic characteristics of the machine and a rotor position signal to provide an estimate of current or of supply voltage.
    Type: Grant
    Filed: November 13, 2008
    Date of Patent: February 21, 2012
    Assignee: Nidec SR Drives Ltd.
    Inventors: Michael Paul Tankard, James Douglas Alexander Chambers
  • Deriving Values of Parameters in Electrical Machines
    Publication number: 20090134831
    Abstract: An electrical drive system includes an electrical machine controlled by an electronic controller and requires control signals representing quantities associated with the operation of the electrical machine. These signals may represent, for example, rotor position and flux or current. A controller includes an estimation routine to use the known magnetic characteristics of the machine and a rotor position signal to provide an estimate of current or of supply voltage.
    Type: Application
    Filed: November 13, 2008
    Publication date: May 28, 2009
    Applicant: SWITCHED RELUCTANCE DRIVES LIMITED
    Inventors: Michael Paul Tankard, James Douglas Alexander Chambers
  • Rotor position determination in a switched reluctance machine
    Patent number: 6979974
    Abstract: A switched reluctance drive is controlled without using a physical rotor position detector. The control method causes current to flow continuously in a single winding when the rotor is turning and detects position by finding either the peak of the current waveform or some other feature which can be uniquely related to the position of the rotor.
    Type: Grant
    Filed: April 23, 2004
    Date of Patent: December 27, 2005
    Assignee: Switched Reluctance Drives Limited
    Inventors: Howard James Slater, James Douglas Alexander Chambers
  • Rotor position determination in a switched reluctance machine
    Publication number: 20040212359
    Abstract: A switched reluctance drive is controlled without using a physical rotor position detector. The control method causes current to flow continuously in a single winding when the rotor is turning and detects position by finding either the peak of the current waveform or some other feature which can be uniquely related to the position of the rotor.
    Type: Application
    Filed: April 23, 2004
    Publication date: October 28, 2004
    Applicant: SWITCHED RELUCTANCE DRIVES LIMITED
    Inventors: Howard James Slater, James Douglas Alexander Chambers