Patents by Inventor Jackson Wai

Jackson Wai 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).

  • Publication number: 20220231626
    Abstract: Power based self-sensing of a rotor position of an SR motor at mid to high speeds and low torque is achieved by an SR motor control system by comparing the motor power to an injection maximum power. A position current pulse is injected to a stator pole in response to the motor power being less than the injection maximum power. An actual stator current created by the position current pulse is compared to an estimated stator current, and a stored estimated rotor position in a memory is updated to a new estimated rotor position if the actual stator current is not equal to the estimated stator current.
    Type: Application
    Filed: January 21, 2021
    Publication date: July 21, 2022
    Applicant: Caterpillar Inc.
    Inventors: Jesse Ray Gerdes, James Michael Thorne, Ahmed Khalil, Jackson Wai, Sajan Abdul, Amara Ashfaq
  • Publication number: 20220200502
    Abstract: A system and method for torque compensation in a switched reluctance (SR) machine disposed on a machine is disclosed. The system may comprise a SR machine, an inverter and a controller. The controller is in operable communication with the inverter and is configured to determine a commanded main current associated with energization by a main current of a first portion of the plurality of windings for a controlling phase, and determine a commanded parasitic current associated with energization by a parasitic current of a second portion of the windings in a non-controlling phase. The controller is further configured to determine an offset current based on the commanded parasitic current, and determine a target current based on a first sum of the commanded main current and the offset current, and command the inverter to actuate the target current in the first portion of the windings during the controlling phase.
    Type: Application
    Filed: December 21, 2020
    Publication date: June 23, 2022
    Applicant: Caterpillar Inc.
    Inventors: Jesse R. Gerdes, Jackson Wai, Ahmed Khalil, James Michael Thorne, Sajan Abdul, Amara Ashfaq
  • Publication number: 20220200501
    Abstract: A work machine includes a frame, a traction system supporting the frame, a power source mounted on the frame, a switched reluctance motor, an inverter configured to control power to the motor from a power source, and a controller. The controller is configured to receive a signal indicating a desired torque and determine if the desired torque is between an upper threshold and a lower threshold. If the desired torque is between the upper threshold and the lower threshold, pulse width modulation is used to produce a PWM adjusted torque command, and the motor is commanded based on the PWM adjusted torque command. The PWM adjusted torque command is configured to cycle between the upper threshold and the lower threshold to produce the desired torque.
    Type: Application
    Filed: December 23, 2020
    Publication date: June 23, 2022
    Applicant: Caterpillar Inc.
    Inventors: Jesse R. Gerdes, Thomas M. Sopko, Carlos E. Nino Baron, Jackson Wai, Ahmed Khalil, Sajan Abdul, Amara Ashfaq, James Michael Thorne
  • Patent number: 10938332
    Abstract: A control system that includes a converter circuit and a control device is disclosed. The converter circuit may be configured to control a phase current of a switched reluctance machine. The control device may be configured to determine an estimated flux based on a bus voltage, a phase voltage, and a mutual voltage. The control device may be configured to determine a flux threshold based on the phase current, and determine a first limit and a second limit relative to the flux threshold. The first limit and the second limit may be scaled relative to the flux threshold based on one or more of the target speed, the load demand, or the bus voltage. The control device may be configured to compare the estimated flux with the first limit, and reset the estimated flux to the second limit based on determining that the estimated flux satisfies the first limit.
    Type: Grant
    Filed: October 7, 2019
    Date of Patent: March 2, 2021
    Assignee: Caterpillar Inc.
    Inventors: Ahmed Khalil, James Thorne, Jackson Wai, Amara Ashfaq, Jesse Gerdes
  • Patent number: 10897217
    Abstract: A device may receive a current measurement of a motor identifying a plurality of component currents associated with a plurality of phases. The device may determine a position estimate for the motor based on the plurality of component currents associated with the plurality of phases. The device may control the motor based on the plurality of component currents.
    Type: Grant
    Filed: August 21, 2018
    Date of Patent: January 19, 2021
    Assignee: Caterpillar Inc.
    Inventors: Ahmed Khalil, Sam Han, James Thorne, Jesse Gerdes, Jackson Wai, Carlos Nino Baron, Sajan Abdul
  • Patent number: 10715052
    Abstract: An electrical inverter may include a plurality of phase modules to provide a plurality of phase outputs. Two or more of the plurality of phase modules may share a common insulated-gate bipolar transistor.
    Type: Grant
    Filed: August 22, 2018
    Date of Patent: July 14, 2020
    Assignee: Caterpillar Inc.
    Inventors: Ahmed Khalil, Jackson Wai, Jesse Gerdes, James Thorne, Amir Saad
  • Patent number: 10666182
    Abstract: A control system for a rotary electric machine includes a controller configured to generate dynamic input current data based upon a dynamic analysis of self flux data, mutual flux data, and saturation scaling factor data. Upon generating a torque request, the controller is configured to determine a desired electrical input based upon the dynamic input current data to generate the desired output torque. The desired electrical input includes a magnitude and duration of an electrical pulse and a desired angular position of the rotor of the rotary electric machine relative to the stator of the machine. The controller determines an angular position of the rotor and generates an operating command to generate the desired electrical input at the desired angular position of the rotor to propel the rotary electric machine and generate the desired output torque. A rotary electric machine and method of operating same are provided.
    Type: Grant
    Filed: April 6, 2018
    Date of Patent: May 26, 2020
    Assignee: Caterpillar Inc.
    Inventors: Carlos E. Nino Baron, Ahmed Khalil, Jackson Wai, Jesse R. Gerdes, Sangameshwar Sonth, Amir Saad
  • Publication number: 20200067422
    Abstract: An electrical inverter may include a plurality of phase modules to provide a plurality of phase outputs. Two or more of the plurality of phase modules may share a common insulated-gate bipolar transistor.
    Type: Application
    Filed: August 22, 2018
    Publication date: February 27, 2020
    Applicant: Caterpillar Inc.
    Inventors: Ahmed Khalil, Jackson Wai, Jesse Gerdes, James Thorne, Amir Saad
  • Publication number: 20200067433
    Abstract: A device may receive a current measurement of a motor identifying a plurality of component currents associated with a plurality of phases. The device may determine a position estimate for the motor based on the plurality of component currents associated with the plurality of phases. The device may control the motor based on the plurality of component currents.
    Type: Application
    Filed: August 21, 2018
    Publication date: February 27, 2020
    Applicant: Caterpillar Inc.
    Inventors: Ahmed KHALIL, Sam HAN, James THORNE, Jesse GERDES, Jackson WAI, Carlos NINO BARON, Sajan ABDUL
  • Patent number: 10476421
    Abstract: A device may select an operation mode based on at least one of a motor speed, a motor transient speed, or a motor power command value. The operation mode may be selected from a group of operation modes including a single pulse mode, a continuous conduction mode, and a variable dwell continuous conduction mode. The device may control a switched reluctance motor using the operation mode.
    Type: Grant
    Filed: August 28, 2018
    Date of Patent: November 12, 2019
    Assignee: Caterpillar Inc.
    Inventors: Ahmed Khalil, Carlos Nino Baron, Chad Brewer, Jackson Wai, Yash Bhatia
  • Patent number: 10193475
    Abstract: A method for determining rotor position of a switched reluctance (SR) machine having a rotor and a stator is provided. The method may include injecting a test pulse into one or more idle phases of the SR machine, determining a decoupled flux value based at least partially on a total flux value corresponding to the test pulse and a mutual flux value, and determining the rotor position based at least partially on the decoupled flux value.
    Type: Grant
    Filed: May 18, 2015
    Date of Patent: January 29, 2019
    Assignee: Caterpillar Inc.
    Inventors: Seok-hee Han, Carlos Nino Baron, Jackson Wai, Ahmed Khalil, Ernesto Inoa, Jesse Gerdes, James Michael Thorne
  • Patent number: 10097117
    Abstract: A control system is provided for an electric machine having a rotor and a stator. The control system has a converter circuit in electrical communication with the stator and a controller in electrical communication with the converter circuit. The controller is configured to receive a first signal indicating a torque applied to or output by the rotor and receive a second signal indicating a rotational speed of the rotor. The controller is also configured to determine at least one characteristic of a pulse signal based on at least one of the first or second signal. The controller is also configured to inject the pulse signal into one or more phases of the stator via the converter circuit according to the determined at least one characteristic. The controller is also configured to determine a position of the rotor based on the injected pulse signal.
    Type: Grant
    Filed: December 15, 2016
    Date of Patent: October 9, 2018
    Assignee: Caterpillar Inc.
    Inventors: Ahmed Khalil, Seok-Hee Han, Jackson Wai, Sangameshwar Sonth, Jesse Gerdes, James M. Thorne
  • Patent number: 10079566
    Abstract: A system and method for estimating a position and a speed of a rotor of a Switched Reluctance (SR) machine is provided. The SR machine comprises the rotor, a stator and at least one winding. The method includes generating a diagnostic pulse having a trapezoidal shape. The method further includes injecting a diagnostic pulse into the at least one winding of the SR machine. The method further includes measuring an actual stator current flowing through the at least one winding of the SR machine. The method further includes computing an estimated stator current flowing through the at least one winding using observer-based estimation technique. The estimated stator current is compared with the actual stator current to compute an error signal. At least one of the position and the speed of the rotor is estimated based on the error signal.
    Type: Grant
    Filed: July 14, 2017
    Date of Patent: September 18, 2018
    Assignee: Caterpillar Inc.
    Inventors: Ahmed Khalil, Seok-Hee Han, Jackson Wai, James Michael Thorne, Jesse Gerdes, Sangameshwar Sonth
  • Publication number: 20180175754
    Abstract: A control system is provided for an electric machine having a rotor and a stator. The control system has a converter circuit in electrical communication with the stator and a controller in electrical communication with the converter circuit. The controller is configured to receive a first signal indicating a torque applied to or output by the rotor and receive a second signal indicating a rotational speed of the rotor. The controller is also configured to determine at least one characteristic of a pulse signal based on at least one of the first or second signal. The controller is also configured to inject the pulse signal into one or more phases of the stator via the converter circuit according to the determined at least one characteristic. The controller is also configured to determine a position of the rotor based on the injected pulse signal.
    Type: Application
    Filed: December 15, 2016
    Publication date: June 21, 2018
    Applicant: Caterpillar Inc.
    Inventors: Ahmed KHALIL, Seok-Hee HAN, Jackson WAI, Sangameshwar SONTH, Jesse GERDES, James M. THORNE
  • Patent number: 9941831
    Abstract: A control system for a switched reluctance (SR) motor includes a Direct Current (DC) power source, and an inverter. The control system includes a user interface configured to enable an operator to specify a desired torque output. The control system further includes a controller which converts a DC current from the Alternating Current (AC) supplied to the SR motor by the inverter. The controller estimates an actual power output generated by the SR motor based on a DC voltage supplied by the DC power source to the inverter, and the converted DC current. The controller estimates an actual torque output based on the actual power output and a rotational speed of the SR motor. The controller compares the actual torque output and a desired torque output to calculate a torque error. The controller adjusts a torque output limit and the rotational speed of the SR motor.
    Type: Grant
    Filed: June 9, 2017
    Date of Patent: April 10, 2018
    Assignee: Caterpillar Inc.
    Inventors: Jason L. Miller, Ernesto Inoa, Jesse Gerdes, Alexander C. Crosman, III, Carlos E. Nino-Baron, Thomas Michael Sopko, Jr., Jackson Wai, Ahmed Khalil
  • Patent number: 9899946
    Abstract: A control system for a switched reluctance (SR) machine having a rotor and a stator is provided. The control system may include a converter circuit in electrical communication between the stator and a common bus, and a controller configured to monitor a bus voltage of the converter circuit and a phase current of the SR machine. The controller may be configured to determine a phase voltage based on one or more of main pulses and any diagnostic pulses, determine an estimated flux based on the phase voltage and an associated mutual voltage, determine a rotor position based at least partially on the estimated flux, and control the SR machine based on the rotor position and a desired torque.
    Type: Grant
    Filed: February 10, 2016
    Date of Patent: February 20, 2018
    Assignee: Caterpillar Inc.
    Inventors: Seok-hee Han, Jackson Wai, Ahmed Khalil, Ernesto Inoa, Sangameshwar Sonth, Jesse Gerdes, James Michael Thorne
  • Patent number: 9800192
    Abstract: A control system for a multi-phase switched reluctance (SR) machine, having at least two phases, is disclosed. The control system may include a converter circuit and a controller. The controller may include a phase voltage estimator module configured to determine a first phase voltage and a second phase voltage associated with a second phase second phase for the SR machine. The controller may further include a flux estimator module configured to determine first and second estimated fluxes, the first estimated flux associated with the first phase and based on the first phase voltage and an associated first mutual voltage and the second estimated flux the second estimated flux associated with the second phase and based on the second phase voltage and an associated second mutual voltage, and a position observer module configured to determine a rotor position based at least partially on the first estimated flux, the second mutual flux.
    Type: Grant
    Filed: April 7, 2016
    Date of Patent: October 24, 2017
    Assignee: Caterpillar Inc.
    Inventors: Seok-hee Han, Jackson Wai, Ahmed Khalil, Jesse Gerdes, James Michael Thorne, Sangameshwar Sonth
  • Publication number: 20170294858
    Abstract: A control system for a multi-phase switched reluctance (SR) machine, having at least two phases, is disclosed. The control system may include a converter circuit and a controller. The controller may include a phase voltage estimator module configured to determine a first phase voltage and a second phase voltage associated with a second phase second phase for the SR machine. The controller may further include a flux estimator module configured to determine first and second estimated fluxes, the first estimated flux associated with the first phase and based on the first phase voltage and an associated first mutual voltage and the second estimated flux the second estimated flux associated with the second phase and based on the second phase voltage and an associated second mutual voltage, and a position observer module configured to determine a rotor position based at least partially on the first estimated flux, the second mutual flux.
    Type: Application
    Filed: April 7, 2016
    Publication date: October 12, 2017
    Applicant: Caterpillar Inc.
    Inventors: Seok-hee Han, Jackson Wai, Ahmed Khalil, Jesse Gerdes, James Michael Thorne, Sangameshwar Sonth
  • Patent number: 9738163
    Abstract: The present disclosure is directed to an electric drive. The electric drive may include a first power inverter, a second power inverter, and a positive DC bus connecting the first power inverter and the second power inverter. The electric drive may also include a first switch connected to the positive DC bus between the first power inverter and the second power inverter. The electric drive may include a second switch connected to the positive DC bus between the first power inverter and the second power inverter. The electric drive may further include a control unit connected to the first switch and to the second switch. The control unit may be configured to selectively allow current to pass through the first switch and the second switch.
    Type: Grant
    Filed: December 2, 2014
    Date of Patent: August 22, 2017
    Assignee: Caterpillar Inc.
    Inventors: Rodwan Tarek Adra, Thomas Michael Sopko, Jr., Jackson Wai, Carlos Eduardo Nino Baron
  • Publication number: 20170229992
    Abstract: A control system for a switched reluctance (SR) machine having a rotor and a stator is provided. The control system may include a converter circuit in electrical communication between the stator and a common bus, and a controller configured to monitor a bus voltage of the converter circuit and a phase current of the SR machine. The controller may be configured to determine a phase voltage based on one or more of main pulses and any diagnostic pulses, determine an estimated flux based on the phase voltage and an associated mutual voltage, determine a rotor position based at least partially on the estimated flux, and control the SR machine based on the rotor position and a desired torque.
    Type: Application
    Filed: February 10, 2016
    Publication date: August 10, 2017
    Applicant: Caterpillar Inc.
    Inventors: Seok-hee Han, Jackson Wai, Ahmed Khalil, Ernesto Inoa, Sangameshwar Sonth, Jesse Gerdes, James Michael Thorne