Patents by Inventor Leah Dunbar

Leah Dunbar 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: 9759737
    Abstract: A first counter is incremented when a first rotational speed sensing device detects a falling edge of one of the teeth of a single multi-tooth target wheel, a second counter is incremented when a second rotational speed sensing device detects a falling edge of one of the teeth, and a third counter is incremented when either of the first and second rotational speed sensing devices detects either of a rising edge and a falling edge of one of the teeth. A direction of rotation is determined based upon the third counter and a rotational speed of the rotatable member is determined based upon one of the first and second counters. The rotatable member is indicated to be at zero speed when the rotational speed is less than a threshold speed and the direction of rotation changes between a positive direction and a negative direction.
    Type: Grant
    Filed: December 4, 2014
    Date of Patent: September 12, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Leah Dunbar, Yo Chan Son, Martin E. Rosalik, Jr., Justin O. Nielsen
  • Patent number: 9566985
    Abstract: A method for monitoring an electrically-powered torque machine configured to generate torque in a hybrid powertrain system includes monitoring signal outputs of a resolver configured to monitor rotational position of the torque machine. Upon detecting a fault warning state associated with the signal outputs of the resolver, a motor torque capacity of the torque machine is derated. Upon a clearing of the fault warning state, a torque ramp-up state to increase the motor torque capacity of the torque machine is executed. Notice of an incidence of a fault associated with the signal outputs of the resolver is provided only when the motor torque capacity fails to achieve a threshold motor torque capacity within a threshold recovery time period while executing the torque ramp-up state.
    Type: Grant
    Filed: February 8, 2011
    Date of Patent: February 14, 2017
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Wei D. Wang, Bon Ho Bae, Leah Dunbar, Kevin P. Houle, William R. Cawthorne, Andrew M. Zettel, Hanne Buur, Steven E. Schulz
  • Publication number: 20160054351
    Abstract: A first counter is incremented when a first rotational speed sensing device detects a falling edge of one of the teeth of a single multi-tooth target wheel, a second counter is incremented when a second rotational speed sensing device detects a falling edge of one of the teeth, and a third counter is incremented when either of the first and second rotational speed sensing devices detects either of a rising edge and a falling edge of one of the teeth. A direction of rotation is determined based upon the third counter and a rotational speed of the rotatable member is determined based upon one of the first and second counters. The rotatable member is indicated to be at zero speed when the rotational speed is less than a threshold speed and the direction of rotation changes between a positive direction and a negative direction.
    Type: Application
    Filed: December 4, 2014
    Publication date: February 25, 2016
    Inventors: Leah Dunbar, Yo Chan Son, Martin E. Rosalik, JR., Justin O. Nielsen
  • Patent number: 9106177
    Abstract: Methods and systems for controlling an electric motor are provided. An estimated rotor flux angular position error is generated based on estimated back electromotive force (EMF) values, and based on the estimated rotor flux angular position error, an estimated rotor flux angular position, an estimated electrical synchronous frequency and/or an estimated rotor frequency can be generated.
    Type: Grant
    Filed: January 5, 2012
    Date of Patent: August 11, 2015
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Yo Chan Son, Leah Dunbar, Silva Hiti
  • Patent number: 9093933
    Abstract: A method for monitoring an electric motor employing a pulse-type rotational position sensor includes monitoring a signal output from the pulse-type rotational position sensor and a reference signal associated with a control signal for the electric motor. A position of a rotor of the electric motor coincident with the reference signal is determined based upon a nominal rotor position, a nominal rotational speed of the rotor and a time between the reference signal and a falling edge of the signal output from the pulse-type rotational position sensor. The electric motor is controlled based upon the position of the rotor.
    Type: Grant
    Filed: August 27, 2013
    Date of Patent: July 28, 2015
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Jihoon Jang, Yo Chan Son, Steven E. Schulz, Leah Dunbar, Terry Murrell, Daniel L. Kowalewski, Silva Hiti
  • Publication number: 20150207444
    Abstract: A vehicle includes a motor having a rotor shaft, a transmission having a gear set directly or selectively connected to the motor, a resolver circuit, and a controller. The resolver circuit includes a resolver that measures an absolute position of the shaft, and a resolver-to-digital converter (RDC) which receives the absolute position and generates, via a tracking loop, a raw position signal. The controller includes recorded predetermined frequency characteristics of the RDC and method instructions which cause the controller to receive the raw position signal from the RDC and create a lookup table describing position wobble. The controller compensates for the position wobble at all rotational speeds of the rotor shaft by applying the predetermined frequency characteristics to the position wobble to derive a compensated position signal. The controller also uses the compensated position signal to control an operation of the electric motor.
    Type: Application
    Filed: January 21, 2014
    Publication date: July 23, 2015
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Yo Chan Son, Bon Ho Bae, Steven E. Schulz, Leah Dunbar
  • Publication number: 20150061563
    Abstract: A method for monitoring an electric motor employing a pulse-type rotational position sensor includes monitoring a signal output from the pulse-type rotational position sensor and a reference signal associated with a control signal for the electric motor. A position of a rotor of the electric motor coincident with the reference signal is determined based upon a nominal rotor position, a nominal rotational speed of the rotor and a time between the reference signal and a falling edge of the signal output from the pulse-type rotational position sensor. The electric motor is controlled based upon the position of the rotor.
    Type: Application
    Filed: August 27, 2013
    Publication date: March 5, 2015
    Applicant: GM Global Technology Operations LLC
    Inventors: JIHOON JANG, YO CHAN SON, STEVEN E. SCHULZ, LEAH DUNBAR, TERRY MURRELL, DANIEL L. KOWALEWSKI, SILVA HITI
  • Patent number: 8634976
    Abstract: A method for operating an electric motor is provided. The method includes receiving a torque request; determining long term torque capabilities and short term torque capabilities of the electric motor; generating a torque command based on the torque request and at least one of the long term torque capabilities or the short term torque capabilities; and controlling the electric motor in accordance with the torque command.
    Type: Grant
    Filed: March 1, 2010
    Date of Patent: January 21, 2014
    Assignee: GM Global Technology Operations LLC
    Inventors: Brian A. Welchko, Nitinkumar R. Patel, Leah Dunbar, William R. Cawthorne, Steven E. Schulz
  • Publication number: 20130175955
    Abstract: Methods and systems for controlling an electric motor are provided. An estimated rotor flux angular position error is generated based on estimated back electromotive force (EMF) values, and based on the estimated rotor flux angular position error, an estimated rotor flux angular position, an estimated electrical synchronous frequency and/or an estimated rotor frequency can be generated.
    Type: Application
    Filed: January 5, 2012
    Publication date: July 11, 2013
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: YO CHAN SON, LEAH DUNBAR, SILVA HITI
  • Patent number: 8294413
    Abstract: A control system is provided for an inverter assembly associated with an induction motor. The system includes a current determination module configured to generate q- and d-axis current commands based on a torque command. The current determination module is further configured to generate the q-axis current command based on an observed flux linkage and a flux linkage command. The system further includes a motor current control module coupled to the current determination module and configured to generate q- and d-axis voltage commands based on the q- and d-axis current commands generated by the current determination module and a PWM modulator coupled to the motor current control module configured to generate duty cycle signals for operating the inverter assembly based on the q- and d-axis voltage commands generated by the motor current control module.
    Type: Grant
    Filed: January 5, 2010
    Date of Patent: October 23, 2012
    Assignee: GM Global Technology Operations LLC
    Inventors: Min Dai, Bon Ho Bae, Leah Dunbar
  • Patent number: 8261864
    Abstract: A control system for a hybrid powertrain includes an engine start detector that detects when an engine of the hybrid powertrain is activated via an electric motor during an auto start. An electric motor speed monitor determines a first speed of the electric motor for a first time and a second speed of the electric motor for a second time after detection of the engine in an active state. A control module determines a rate of change in speed of the electric motor based on the first speed and the second speed. The control module adjusts torque output of the electric motor during startup of the engine and based on the rate of change in speed.
    Type: Grant
    Filed: May 15, 2009
    Date of Patent: September 11, 2012
    Inventors: Birendra P. Bhattarai, Bon Ho Bae, Leah Dunbar
  • Publication number: 20120203405
    Abstract: A method for monitoring an electrically-powered torque machine configured to generate torque in a hybrid powertrain system includes monitoring signal outputs of a resolver configured to monitor rotational position of the torque machine. Upon detecting a fault warning state associated with the signal outputs of the resolver, a motor torque capacity of the torque machine is derated. Upon a clearing of the fault warning state, a torque ramp-up state to increase the motor torque capacity of the torque machine is executed. Notice of an incidence of a fault associated with the signal outputs of the resolver is provided only when the motor torque capacity fails to achieve a threshold motor torque capacity within a threshold recovery time period while executing the torque ramp-up state.
    Type: Application
    Filed: February 8, 2011
    Publication date: August 9, 2012
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Wei D. Wang, Bon Ho Bae, Leah Dunbar, Kevin P. Houle, William R. Cawthorne, Andrew M. Zettel, Hanne Buur, Steven E. Schulz
  • Publication number: 20110213518
    Abstract: A method for operating an electric motor is provided. The method includes receiving a torque request; determining long term torque capabilities and short term torque capabilities of the electric motor; generating a torque command based on the torque request and at least one of the long term torque capabilities or the short term torque capabilities; and controlling the electric motor in accordance with the torque command.
    Type: Application
    Filed: March 1, 2010
    Publication date: September 1, 2011
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: BRIAN A. WELCHKO, NITINKUMAR R. PATEL, LEAH DUNBAR, WILLIAM R. CAWTHORNE, STEVEN E. SCHULZ
  • Patent number: 7977963
    Abstract: Methods and apparatus are provided for determining whether one or more inverter sub-modules of an inverter module is operating properly. Amplitude of each stator current signal is regularly measured. For each current signal, a positive counter counts a number of consecutive times the amplitude of that current signal is less than a positive current threshold, while a negative counter counts a number of consecutive times the amplitude of that current signal is greater than a negative current threshold. If the positive counter or the negative counter exceeds a maximum count, it is determined that an inverter sub-module is operating abnormally.
    Type: Grant
    Filed: July 21, 2009
    Date of Patent: July 12, 2011
    Assignee: GM Global Technology Operations LLC
    Inventors: Bon Ho Bae, Leah Dunbar
  • Publication number: 20110163709
    Abstract: A control system is provided for an inverter assembly associated with an induction motor. The system includes a current determination module configured to generate q- and d-axis current commands based on a torque command. The current determination module is further configured to generate the q-axis current command based on an observed flux linkage and a flux linkage command. The system further includes a motor current control module coupled to the current determination module and configured to generate q- and d-axis voltage commands based on the q- and d-axis current commands generated by the current determination module and a PWM modulator coupled to the motor current control module configured to generate duty cycle signals for operating the inverter assembly based on the q- and d-axis voltage commands generated by the motor current control module.
    Type: Application
    Filed: January 5, 2010
    Publication date: July 7, 2011
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: MIN DAI, BON HO BAE, LEAH DUNBAR
  • Publication number: 20110018578
    Abstract: Methods and apparatus are provided for determining whether one or more inverter sub-modules of an inverter module is operating properly. Amplitude of each stator current signal is regularly measured. For each current signal, a positive counter counts a number of consecutive times the amplitude of that current signal is less than a positive current threshold, while a negative counter counts a number of consecutive times the amplitude of that current signal is greater than a negative current threshold. If the positive counter or the negative counter exceeds a maximum count, it is determined that an inverter sub-module is operating abnormally.
    Type: Application
    Filed: July 21, 2009
    Publication date: January 27, 2011
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: BON HO BAE, LEAH DUNBAR
  • Publication number: 20090308674
    Abstract: A control system for a hybrid powertrain includes an engine start detector that detects when an engine of the hybrid powertrain is activated via an electric motor during an auto start. An electric motor speed monitor determines a first speed of the electric motor for a first time and a second speed of the electric motor for a second time after detection of the engine in an active state. A control module determines a rate of change in speed of the electric motor based on the first speed and the second speed. The control module adjusts torque output of the electric motor during startup of the engine and based on the rate of change in speed.
    Type: Application
    Filed: May 15, 2009
    Publication date: December 17, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Birendra P. Bhattarai, Bon Ho Bae, Leah Dunbar