Patents by Inventor Caleb W. Secrest

Caleb W. Secrest 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: 11927662
    Abstract: A method of evaluating current sensor measurements of an electric machine system includes acquiring a first current signal corresponding to a first measurement of a first phase current of a three phase electric current supply to an electric machine, and acquiring a second current signal corresponding to a second measurement of a second phase current of the three phase electric current supply. The method also includes determining a machine velocity, shifting the first current signal by a signal processing component to generate a shifted first current signal having a shifted phase, the signal processing component including a tuning parameter that is a function of the machine velocity, calculating an amplitude difference between the shifted first current signal and the second current signal, and determining a plausibility of the first measurement and the second measurement based on the difference.
    Type: Grant
    Filed: May 12, 2022
    Date of Patent: March 12, 2024
    Assignee: BORGWARNER INC.
    Inventors: Caleb W. Secrest, James R. Smith
  • Publication number: 20230366968
    Abstract: A method of evaluating current sensor measurements of an electric machine system includes acquiring a first current signal corresponding to a first measurement of a first phase current of a three phase electric current supply to an electric machine, and acquiring a second current signal corresponding to a second measurement of a second phase current of the three phase electric current supply. The method also includes determining a machine velocity, shifting the first current signal by a signal processing component to generate a shifted first current signal having a shifted phase, the signal processing component including a tuning parameter that is a function of the machine velocity, calculating an amplitude difference between the shifted first current signal and the second current signal, and determining a plausibility of the first measurement and the second measurement based on the difference.
    Type: Application
    Filed: May 12, 2022
    Publication date: November 16, 2023
    Inventors: Caleb W. Secrest, James R. Smith
  • Publication number: 20230106892
    Abstract: A method of controlling a motor controlled by a motor controller that includes a complex vector flux regulator (CV?R). The method includes: receiving at a field weakening regulator of the motor controller a modulation index that is a scaled version of an available voltage available to be provided to the motor by a voltage source; comparing the modulation index to a feedback modulation index to produce an error scalar that has a magnitude in a flux domain; determining a final direction (?final) of the error scalar in the flux domain; and providing the CV?R with flux commands in the d and q domain based on the error scalar and the direction.
    Type: Application
    Filed: October 4, 2021
    Publication date: April 6, 2023
    Inventors: Dwarakanath V. Simili, Caleb W. Secrest
  • Patent number: 11239787
    Abstract: A control system and method of controlling a multi-phase electric machine for controlling the flow of electrical current between a voltage source and the multi-phase electric machine or other application/load. The control system includes, between each phase of the multi-phase electric machine and the voltage source: a high side diode and a high side switch positioned in parallel between a positive terminal of the voltage source and the electric machine with the high side diode being reverse biased with regard to the positive terminal; and a low side diode and a low side switch positioned in parallel between a negative terminal of the voltage source and the electric machine with the low side diode being reverse biased with regard to the electric machine. The control system operates the high side and low side switches to provide efficient operation of the electric machine.
    Type: Grant
    Filed: September 3, 2020
    Date of Patent: February 1, 2022
    Assignee: BorgWarner Inc.
    Inventor: Caleb W. Secrest
  • Publication number: 20210104971
    Abstract: A control system and method of controlling a multi-phase electric machine for controlling the flow of electrical current between a voltage source and the multi-phase electric machine or other application/load. The control system includes, between each phase of the multi-phase electric machine and the voltage source: a high side diode and a high side switch positioned in parallel between a positive terminal of the voltage source and the electric machine with the high side diode being reverse biased with regard to the positive terminal; and a low side diode and a low side switch positioned in parallel between a negative terminal of the voltage source and the electric machine with the low side diode being reverse biased with regard to the electric machine. The control system operates the high side and low side switches to provide efficient operation of the electric machine.
    Type: Application
    Filed: September 3, 2020
    Publication date: April 8, 2021
    Inventor: Caleb W. Secrest
  • Patent number: 10889285
    Abstract: A method for controlling an electric machine in a powertrain system in which a driven load is connected to a rotor of the electric machine includes measuring phase currents at a starting point of a sample period using current sensors connected to phase windings of the electric machine. The individual phase currents also are determined at a midpoint of the previous sample period. An angular position of the rotor is determined at the starting point and previous midpoint before calculating synchronous reference frame currents of the electric machine at the starting and previous midpoint using the phase currents and angular position. The method includes calculating average synchronous reference frame currents over the sample period and regulating operation of the electric machine using the average. An electrical system includes the electric machine, a power inverter module, and a controller that executes the method.
    Type: Grant
    Filed: February 4, 2019
    Date of Patent: January 12, 2021
    Assignee: GM Global Technology Operations LLC
    Inventor: Caleb W. Secrest
  • Publication number: 20200247389
    Abstract: A method for controlling an electric machine in a powertrain system in which a driven load is connected to a rotor of the electric machine includes measuring phase currents at a starting point of a sample period using current sensors connected to phase windings of the electric machine. The individual phase currents also are determined at a midpoint of the previous sample period. An angular position of the rotor is determined at the starting point and previous midpoint before calculating synchronous reference frame currents of the electric machine at the starting and previous midpoint using the phase currents and angular position. The method includes calculating average synchronous reference frame currents over the sample period and regulating operation of the electric machine using the average. An electrical system includes the electric machine, a power inverter module, and a controller that executes the method.
    Type: Application
    Filed: February 4, 2019
    Publication date: August 6, 2020
    Applicant: GM Global Technology Operations LLC
    Inventor: Caleb W. Secrest
  • Patent number: 10668822
    Abstract: A rotary system includes a rotor, a vector-based position sensor, and a controller executing a method to eliminate fundamental harmonic position measurement error. The sensor measures angular position of the rotor and outputs raw sine and cosine signals representative of the angular position. The raw signals have a fundamental harmonic position measurement error at the frequency of the sensor signals. The controller receives the raw signals, adaptively adds or subtracts sensor signal offsets to or from the raw signals to generate offset sine and cosine signals, calculates a corrected position of the rotor using the offset sine and cosine signals eliminating the fundamental error, and controls an action or state of the rotary system using the corrected position. The rotor may be part of an electric machine, such as in a vehicle.
    Type: Grant
    Filed: July 25, 2017
    Date of Patent: June 2, 2020
    Assignee: GM Global Technology Operations LLC
    Inventors: Caleb W. Secrest, David S. Ochs
  • Publication number: 20200127588
    Abstract: A control system for controlling operation of an asymmetric motor to operate as a symmetric motor is provided and includes first and second summers, a proportional flux error-to-voltage converter, a complex integration module, and a control module. The first summer determines a flux error for d and q axes of the asymmetric motor based on a commanded flux value and a feedback flux value. The proportional flux error-to-voltage converter converts the flux error to a proportional voltage term. The complex integration module, based on a time constant, a synchronous angular velocity, and a sampling period, calculates an integral voltage term. The second summer sums the proportional voltage term, the integral voltage term, and a damping resistance voltage to generate a voltage command signal. The damping resistance voltage is based on first and second damping resistances. The control module controls operation of the asymmetric motor based on the voltage command signal.
    Type: Application
    Filed: October 19, 2018
    Publication date: April 23, 2020
    Applicant: GM Global Technology Operations LLC
    Inventors: Caleb W. SECREST, Dwarakanath V . SIMILI, Yo Chan SON
  • Patent number: 10396696
    Abstract: A current regulator is provided for an electric machine drive system for driving an electric machine. The current regulator includes an adjustable damping module that has a value of virtual damping resistance that is applied at the current regulator. The value of virtual damping resistance is adjustable as a function of sampling frequency. A controller can control the current regulator by determining whether the sampling frequency has changed since a previous execution cycle of the current regulator, and when the sampling frequency has changed since the previous execution cycle, the controller can modify the damping value as a function of the sampling frequency to allow the damping value to change with the sampling frequency. The damping value has a new value of virtual damping resistance that is applied at the current regulator after modifying the damping value. The controller can then execute the current regulator in accordance with the modified damping value to generate the voltage commands.
    Type: Grant
    Filed: February 21, 2018
    Date of Patent: August 27, 2019
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Brent S. Gagas, Dwarakanath V. Simili, Caleb W. Secrest
  • Publication number: 20190260319
    Abstract: A current regulator is provided for an electric machine drive system for driving an electric machine. The current regulator includes an adjustable damping module that has a value of virtual damping resistance that is applied at the current regulator. The value of virtual damping resistance is adjustable as a function of sampling frequency. A controller can control the current regulator by determining whether the sampling frequency has changed since a previous execution cycle of the current regulator, and when the sampling frequency has changed since the previous execution cycle, the controller can modify the damping value as a function of the sampling frequency to allow the damping value to change with the sampling frequency. The damping value has a new value of virtual damping resistance that is applied at the current regulator after modifying the damping value. The controller can then execute the current regulator in accordance with the modified damping value to generate the voltage commands.
    Type: Application
    Filed: February 21, 2018
    Publication date: August 22, 2019
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Brent S. Gagas, Dwarakanath V. Simili, Caleb W. Secrest
  • Patent number: 10355631
    Abstract: A current regulator is provided for an electric machine drive system for driving an electric machine. The current regulator is configurable to operate in a first configuration or a second configuration depending on a synchronous speed of the electric machine. A controller can configure an operational mode of the current regulator by selecting, based on the synchronous speed of the electric machine, either the first configuration of the current regulator or the second configuration of the current regulator as a currently active configuration, and can then execute the current regulator in accordance with the currently active configuration. The first configuration of the current regulator comprises a first set of elements and cross-coupling gain blocks, whereas the second configuration of the current regulator can include the first set of elements without the cross-coupling gain blocks.
    Type: Grant
    Filed: February 21, 2018
    Date of Patent: July 16, 2019
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Caleb W. Secrest, Brent S. Gagas, Dwarakanath V. Simili
  • Patent number: 10326390
    Abstract: Systems and method for operating motors are provided. In an exemplary embodiment, a method for operating a motor includes receiving a first output corresponding to a motor angular position. The method further includes synthesizing a synthesized second output from the first output and from an estimated motor angular velocity. The method also includes calculating the motor angular position from the first output and the synthesized second output. The method includes estimating the motor angular velocity from the motor angular position. Further, the method includes operating the motor to produce torque based on the motor angular position and the motor angular velocity.
    Type: Grant
    Filed: July 24, 2017
    Date of Patent: June 18, 2019
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: David S. Ochs, Yo Chan Son, Caleb W. Secrest
  • Patent number: 10319360
    Abstract: In various embodiments, methods, systems, and vehicles are provided for masking a tonal noise of a motor. In certain embodiments, a vehicle includes a drive system and an active masking acoustic signal generator (AMAG). The drive system includes a motor generating a tonal noise. The AMAG is configured to at least facilitate masking the tonal noise, by introducing a complementary harmonic tone, injecting dithering into the motor, or both.
    Type: Grant
    Filed: March 6, 2018
    Date of Patent: June 11, 2019
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Song He, Yo Chan Son, Gilsu Choi, Caleb W. Secrest, Aja Anjilivelil, Scott M. Reilly, John P. Miller
  • Publication number: 20190031046
    Abstract: A rotary system includes a rotor, a vector-based position sensor, and a controller executing a method to eliminate fundamental harmonic position measurement error. The sensor measures angular position of the rotor and outputs raw sine and cosine signals representative of the angular position. The raw signals have a fundamental harmonic position measurement error at the frequency of the sensor signals. The controller receives the raw signals, adaptively adds or subtracts sensor signal offsets to or from the raw signals to generate offset sine and cosine signals, calculates a corrected position of the rotor using the offset sine and cosine signals eliminating the fundamental error, and controls an action or state of the rotary system using the corrected position. The rotor may be part of an electric machine, such as in a vehicle.
    Type: Application
    Filed: July 25, 2017
    Publication date: January 31, 2019
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Caleb W. Secrest, David S. Ochs
  • Publication number: 20190028044
    Abstract: Systems and method for operating motors are provided. In an exemplary embodiment, a method for operating a motor includes receiving a first output corresponding to a motor angular position. The method further includes synthesizing a synthesized second output from the first output and from an estimated motor angular velocity. The method also includes calculating the motor angular position from the first output and the synthesized second output. The method includes estimating the motor angular velocity from the motor angular position. Further, the method includes operating the motor to produce torque based on the motor angular position and the motor angular velocity.
    Type: Application
    Filed: July 24, 2017
    Publication date: January 24, 2019
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: David S. Ochs, Yo Chan Son, Caleb W. Secrest
  • Patent number: 10156462
    Abstract: A system includes a rotary device, a vector-based position sensor outputting raw sine and cosine signals indicative of an angular position of the rotary device, and a controller. The controller executes a method by receiving the raw sine and cosine signals from the sensor, generating corrected sine and cosine signals by applying an amplitude error input signal to a first integrator block using a first predetermined trigonometric relationship, and executing a control action for the rotary device via output signals using the corrected signals. The first predetermined trigonometric relationship is SC2?CC2, with SC and CC being the respective corrected sine and cosine signals. The controller may use a second predetermined trigonometric relationship, SC·CC, to apply an orthogonality error input signal to a second integrator block.
    Type: Grant
    Filed: November 7, 2016
    Date of Patent: December 18, 2018
    Assignee: GM Global Technology Operations LLC
    Inventors: David S. Ochs, Caleb W. Secrest, Yo Chan Son
  • Publication number: 20180128658
    Abstract: A system includes a rotary device, a vector-based position sensor outputting raw sine and cosine signals indicative of an angular position of the rotary device, and a controller. The controller executes a method by receiving the raw sine and cosine signals from the sensor, generating corrected sine and cosine signals by applying an amplitude error input signal to a first integrator block using a first predetermined trigonometric relationship, and executing a control action for the rotary device via output signals using the corrected signals. The first predetermined trigonometric relationship is SC2-CC2, with SC and CC being the respective corrected sine and cosine signals. The controller may use a second predetermined trigonometric relationship, SC·CC, to apply an orthogonality error input signal to a second integrator block.
    Type: Application
    Filed: November 7, 2016
    Publication date: May 10, 2018
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: David S. Ochs, Caleb W. Secrest, Yo Chan Son