Patents by Inventor Tomy Sebastian

Tomy Sebastian 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: 9136785
    Abstract: A motor control system is provided. The motor control system includes a motor having plurality of motor harmonics, and a torque ripple compensation controller in communication with the motor. The torque ripple compensation controller is configured to determine a harmonic ripple current for a corresponding one of the plurality of motor harmonics. The harmonic ripple current is based on a reference q-axis current and a reference d-axis current. The torque ripple compensation controller is configured to add the harmonic ripple current for each of the plurality of motor harmonics together to determine the ripple compensating current.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: September 15, 2015
    Assignee: Steering Solutions IP Holding Corporation
    Inventors: Abraham Gebregergis, Mohammad S. Islam, Tomy Sebastian, Mazharul H. Chowdhury, Shakil Hossain, Ramakrishnan RajaVenkitasubramony, Niharika P. Popy
  • Patent number: 9054612
    Abstract: A motor control system is provided. The motor control system includes a motor having plurality of motor harmonics, and a torque ripple compensation controller in communication with the motor. The torque ripple compensation controller is configured to determine a harmonic ripple current for a corresponding one of the plurality of motor harmonics. The harmonic ripple current is based on a reference q-axis current and a reference d-axis current. The torque ripple compensation controller is configured to add the harmonic ripple current for each of the plurality of motor harmonics together to determine the ripple compensating current.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: June 9, 2015
    Assignee: Steering Solutions IP Holding Corporation
    Inventors: Abraham Gebregergis, Mohammad S. Islam, Tomy Sebastian, Mazharul H. Chowdhury, Shakil Hossain, Ramakrishnan RajaVenkitasubramony, Niharika P. Popy
  • Patent number: 8924082
    Abstract: A method for controlling operation of a torque-assist motor includes determining a rotational position of the torque-assist motor and producing a motor speed signal that is indicative of a rotational speed of the motor. One or more gain factors are produced based on the rotational speed of the torque-assist motor. An electrical current applied to the torque-assist motor is detected, and a current error is calculated based on a commanded electrical current and the electrical current applied to the torque-assist motor. A quadrature axis voltage is calculated based on the current error and the one or more gain factors. An inverter is driven with a direct voltage signal that is phased with the rotational position of the torque-assist motor so as to produce the electrical current applied to the torque-assist motor. The electrical current exhibits a characteristic that is affected by the quadrature axis voltage.
    Type: Grant
    Filed: March 30, 2012
    Date of Patent: December 30, 2014
    Assignee: Steering Solutions IP Holding Corporation
    Inventors: Abraham Gebregergis, Ramakrishnan RajaVenkitasubramony, Tomy Sebastian, Niharika P. Popy
  • Publication number: 20140265951
    Abstract: A motor control system for determining a reference d-axis current and a reference q-axis current is provided. The motor control system includes a motor, a DC power source and DC input lines, and a current command controller. The DC power source generates a bridge voltage across the DC input lines. The current command controller is configured to monitor the bridge voltage and a torque reference command. The current command controller is configured to calculate the reference q-axis current based on a torque reference command. The current command controller is configured to calculate the reference d-axis current based on a magnitude of the reference q-axis current.
    Type: Application
    Filed: March 12, 2013
    Publication date: September 18, 2014
    Applicant: Steering Solutions IP Holding Corporation
    Inventors: Abraham Gebregergis, Ramakrishnan RajaVenkitasubramony, Tomy Sebastian, Siddharth Ballal
  • Publication number: 20140265962
    Abstract: A motor control system for determining a ripple compensating current is provided. The motor control system includes a motor having a plurality of motor harmonics and a motor frequency, and a bandwidth compensation controller that is in communication with the motor. The bandwidth compensation controller is configured to determine a magnitude response compensation value and a phase compensation value for each of the plurality of motor harmonics. The magnitude response compensation value and the phase compensation value are both based on the motor frequency. The bandwidth compensation controller is configured to determine the ripple compensating current based on the magnitude response compensation value and the phase compensation value.
    Type: Application
    Filed: March 14, 2013
    Publication date: September 18, 2014
    Applicant: STEERING SOLUTIONS IP HOLDING CORPORATION
    Inventors: Abraham Gebregergis, Ramakrishnan RajaVenkitasubramony, Tomy Sebastian, Niharika P. Popy
  • Publication number: 20140265961
    Abstract: A motor control system is provided. The motor control system includes a motor having plurality of motor harmonics, and a torque ripple compensation controller in communication with the motor. The torque ripple compensation controller is configured to determine a harmonic ripple current for a corresponding one of the plurality of motor harmonics. The harmonic ripple current is based on a reference q-axis current and a reference d-axis current. The torque ripple compensation controller is configured to add the harmonic ripple current for each of the plurality of motor harmonics together to determine the ripple compensating current.
    Type: Application
    Filed: March 12, 2013
    Publication date: September 18, 2014
    Applicant: Steering Solutions IP Holding Corporation
    Inventors: Abraham Gebregergis, Mohammad S. Islam, Tomy Sebastian, Mazharul H. Chowdhury, Shakil Hossain, Ramakrishnan RajaVenkitasubramony, Niharika P. Popy
  • Publication number: 20140265986
    Abstract: A motor control system is provided, and includes a motor, at least one differential amplifier configured to monitor phase current applied to the motor, and a current compensation controller. The current compensation controller is in communication with the at least one differential amplifier, and is configured to periodically determine a common-mode voltage of the at least one differential amplifier. The current compensation controller is also configured to determine a corrected phase current value based on the common mode voltage.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Applicant: STEERING SOLUTIONS IP HOLDING CORPORATION
    Inventors: Abraham G. Gebregergis, Ramakrishnan RajaVenkitasubramony, Tomy Sebastian, Santhosh J. Veigas, Vaughn E. Lietzke
  • Publication number: 20140253000
    Abstract: A motor control system for determining a reference d-axis current is provided, and includes a motor, a DC power source and DC input lines, and a current command controller. The DC power source generates a bridge voltage across the DC input lines. The current command controller is in communication with the motor and the DC input lines. The current command controller is configured to monitor the bridge voltage and a torque reference command. The current command controller is configured to determine a peak current based on the torque reference command. The current command controller is configured to determine a current angle based on the peak current. The current command controller is configured to determine the reference d-axis current based on the current angle.
    Type: Application
    Filed: March 11, 2013
    Publication date: September 11, 2014
    Applicant: Steering Solutions IP Holding Corporation
    Inventors: Abraham G. Gebregergis, Ramakrishnan RajaVenkitasubramony, Tomy Sebastian, Siddharth Ballal
  • Publication number: 20140253004
    Abstract: A motor control system for determining an offset correction value is provided. The motor control system includes a motor, an inverter, an inverter controller, and a dynamic offset compensation control module. The inverter is configured to transmit the phase current to the motor. The inverter controller determines the phase current to the motor. The dynamic offset compensation control module is in communication with the inverter controller and the motor, and is configured to perform a method at a fixed periodic interval to determine the offset correction value.
    Type: Application
    Filed: March 5, 2013
    Publication date: September 11, 2014
    Applicant: Steering Solutions IP Holding Corporation
    Inventors: Abraham Gebregergis, Ramakrishnan RajaVenkitasubramony, Tomy Sebastian
  • Publication number: 20140222292
    Abstract: A vehicle electric power steering (EPS) control system includes a motor operatively coupled to an EPS linkage arrangement, the motor comprising a first winding and a second winding. Also included is a power source for the motor. Further included is a controller in operative communication with the motor and the power source. The controller includes a microprocessor configured to receive input from a torque sensor and a motor sensor. The EPS controller also includes a first field-effect transistor (FET) driver in operative communication with the microprocessor and a first plurality of FETs operatively connected to the first winding of the motor. The EPS controller further includes a second FET driver in operative communication with the microprocessor and a second plurality of FETs operatively connected to the second winding of the motor.
    Type: Application
    Filed: February 6, 2014
    Publication date: August 7, 2014
    Applicant: Steering Solutions IP Holding Corporation
    Inventors: Paul M. Fisher, Darryl L. Greathouse, Timothy S. Keister, Eric D. Pattok, Christian E. Ross, Patrik Ryne, Tomy Sebastian
  • Publication number: 20130261896
    Abstract: A method for controlling operation of a torque-assist motor includes determining a rotational position of the torque-assist motor and producing a motor speed signal that is indicative of a rotational speed of the motor. One or more gain factors are produced based on the rotational speed of the torque-assist motor. An electrical current applied to the torque-assist motor is detected, and a current error is calculated based on a commanded electrical current and the electrical current applied to the torque-assist motor. A quadrature axis voltage is calculated based on the current error and the one or more gain factors. An inverter is driven with a direct voltage signal that is phased with the rotational position of the torque-assist motor so as to produce the electrical current applied to the torque-assist motor. The electrical current exhibits a characteristic that is affected by the quadrature axis voltage.
    Type: Application
    Filed: March 30, 2012
    Publication date: October 3, 2013
    Applicant: STEERING SOLUTIONS IP HOLDING CORPORATION
    Inventors: Abraham Gebregergis, Ramakrishnan RajaVenkitasubramony, Tomy Sebastian, Niharika P. Popy
  • Publication number: 20130166141
    Abstract: A steering system for detecting a hand wheel position is provided and includes an input shaft connected to a hand wheel, a main gear disposed around the input shaft, a puck gear meshingly engaged with the main gear, and a control module. The control module receives an angular main position of the main gear and an angular puck position of the puck gear. The control module includes a rotational calculation module for calculating the hand wheel position based on at least the angular main position and the angular puck position.
    Type: Application
    Filed: July 20, 2012
    Publication date: June 27, 2013
    Applicant: STEERING SOLUTIONS IP HOLDING CORPORATION
    Inventors: Zaki Ryne, Keith A. Kidder, Tomy Sebastian, Carl D. Tarum, Paul M. Fisher, Christian E. Ross, Scott T. Blehm
  • Patent number: 8013696
    Abstract: The present invention provides for a magnetic apparatus and a method of manufacturing the magnetic apparatus including a magnet having an outer surface and an inner surface opposing each other with the inner surface having a first portion and a second portion integrally connected to and facing each other and utilizing a fluid and a fixture body defining a hole along a fixture axis and a deflector disposed within the hole. The method includes the steps of installing the magnet on the fixture body and securing the magnet to the fixture body. The method further includes the steps of flowing the fluid through the magnet transverse to the fixture axis to form at least one aperture and intersecting the fluid with the deflector to redirect the fluid generally along the fixture axis.
    Type: Grant
    Filed: October 14, 2008
    Date of Patent: September 6, 2011
    Inventors: Raghunath P. Khetan, Mohammad S. Islam, Matt Mielke, Brian J. Magnus, Tomy Sebastian, Charmaine Wittig, William D. Glumm, Joe Koscielecki
  • Patent number: 7898139
    Abstract: A magnetic actuator, comprising, an inner ring, an outer ring disposed around the inner ring, a first pair of inner teeth disposed on the inner ring that partially define a gap between the first pair of inner teeth having a first angular dimension, a second pair of inner teeth disposed on the inner ring that partially define a gap between the second pair of inner teeth having a second angular dimension, a first pair of outer teeth disposed on the outer ring that partially define a gap between the first pair of outer teeth having a third angular dimension and a second pair of outer teeth disposed on the outer ring that partially define a gap between the second pair of outer teeth having a fourth angular dimension.
    Type: Grant
    Filed: August 7, 2008
    Date of Patent: March 1, 2011
    Inventors: Mohammad S. Islam, Joel E. Birsching, Tomy Sebastian
  • Publication number: 20100089686
    Abstract: The present invention provides for a magnetic apparatus and a method of manufacturing the magnetic apparatus including a magnet having an outer surface and an inner surface opposing each other with the inner surface having a first portion and a second portion integrally connected to and facing each other and utilizing a fluid and a fixture body defining a hole along a fixture axis and a deflector disposed within the hole. The method includes the steps of installing the magnet on the fixture body and securing the magnet to the fixture body. The method further includes the steps of flowing the fluid through the magnet transverse to the fixture axis to form at least one aperture and intersecting the fluid with the deflector to redirect the fluid generally along the fixture axis.
    Type: Application
    Filed: October 14, 2008
    Publication date: April 15, 2010
    Applicant: DELPHI TECHNOLOGIES, INC.
    Inventors: Raghunath P. Khetan, Mohammad S. Islam, Matt Mielke, Brian J. Magnus, Tomy Sebastian, Charmaine Wittig, William D. Glumm, Joe Koscielecki
  • Patent number: 7659679
    Abstract: A system and a method for adjusting a dead-time interval between de-activating a first transistor and activating a second transistor in a motor control circuit are provided. The method includes determining a plurality of commanded torque values associated with a motor based on a received signal over time. The method further includes setting the dead-time interval value equal to a first value when one commanded torque value of the plurality of commanded torque values is within a first torque range. The method further includes decreasing the dead-time interval value as other commanded torque values of the plurality of commanded torque values increase over time within a second torque range. The second torque range is greater than the first torque range. The dead-time interval value is indicative of a desired dead-time interval.
    Type: Grant
    Filed: January 12, 2007
    Date of Patent: February 9, 2010
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Ramakrishnan Raja, Mohammad S. Islam, Paul M. Fisher, Tomy Sebastian, Lucas W. Wendling
  • Patent number: 7639004
    Abstract: An apparatus for measuring relative displacement between a first shaft and a second shaft includes first and second rotor assemblies. The first rotor assembly is coupled to the first shaft and is centered on an axis. The second rotor assembly is coupled to the second shaft. The second rotor assembly has first and second stator plates. Each of the first and second stator plates includes an upper surface and a lower surface. The first and second stator plates include a plurality of teeth extending in a direction radial of the axis. The apparatus further includes at least one magnet having a magnetic field and disposed on the first rotor assembly. The apparatus includes a flux collector arrangement having first and second collectors positioned adjacent the first and second stator plates, respectively, forming a gap. A sensing device disposed within the gap senses a magnetic flux of the magnetic field.
    Type: Grant
    Filed: July 23, 2007
    Date of Patent: December 29, 2009
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Mohammed R. Islam, Mohammad S. Islam, Matthew W Mielke, Tomy Sebastian, Sainan Feng
  • Publication number: 20090236920
    Abstract: A motor comprising, a rotor having a shaped pole operative to minimize cogging torque and electro motive Force (EMF) harmonics, a stator having teeth members, the teeth members including, end portions, wherein the end portions partially define slot openings having a first dimension, and a notch opening defined by the end portions having a second dimension.
    Type: Application
    Filed: March 18, 2008
    Publication date: September 24, 2009
    Applicant: DELPHI TECHNOLOGIES INC.
    Inventors: Mohammad Islam, Ashok Chandy, Tomy Sebastian, Mohammed R. Islam
  • Publication number: 20090050398
    Abstract: A magnetic actuator, comprising, an inner ring, an outer ring disposed around the inner ring, a first pair of inner teeth disposed on the inner ring that partially define a gap between the first pair of inner teeth having a first angular dimension, a second pair of inner teeth disposed on the inner ring that partially define a gap between the second pair of inner teeth having a second angular dimension, a first pair of outer teeth disposed on the outer ring that partially define a gap between the first pair of outer teeth having a third angular dimension and a second pair of outer teeth disposed on the outer ring that partially define a gap between the second pair of outer teeth having a fourth angular dimension.
    Type: Application
    Filed: August 7, 2008
    Publication date: February 26, 2009
    Applicant: DELPHI TECHNOLOGIES INC.
    Inventors: Mohammad S. Islam, Joel E. Birsching, Tomy Sebastian
  • Publication number: 20090027045
    Abstract: An apparatus for measuring relative displacement between a first shaft and a second shaft includes first and second rotor assemblies. The first rotor assembly is coupled to the first shaft and is centered on an axis. The second rotor assembly is coupled to the second shaft. The second rotor assembly has first and second stator plates. Each of the first and second stator plates includes an upper surface and a lower surface. The first and second stator plates include a plurality of teeth extending in a direction radial of the axis. The apparatus further includes at least one magnet having a magnetic field and disposed on the first rotor assembly. The apparatus includes a flux collector arrangement having first and second collectors positioned adjacent the first and second stator plates, respectively, forming a gap. A sensing device disposed within the gap senses a magnetic flux of the magnetic field.
    Type: Application
    Filed: July 23, 2007
    Publication date: January 29, 2009
    Inventors: Mohammed R. Islam, Mohammad S. Islam, Matthew W Mielke, Tomy Sebastian, Sainan Feng