Patents by Inventor Fani S. Gunawan

Fani S. Gunawan 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: 7242163
    Abstract: A device to regulate current produced by a permanent magnet machine responsive to a plurality of phase current signals. The motor produces torque for application on a shaft. A processing and drive circuit responsive to a direct current command signal and a quadrature current command signal produces phase current signals for input to the motor. A command circuit responsive to the phase current signals, an angular position of said shaft, and a voltage input command signal to produce a direct current error signal and a quadrature current error signal. A control circuit responsive to the direct and quadrature current error signals produces the direct voltage signal command and the quadrature voltage signal command. The control circuit has a direct and quadrature proportional gain, integrator and clamp circuits. An algorithm produces limited or clamped voltage modulation index signals to obtain maximum efficiency and maximum torque per ampere in the speed range.
    Type: Grant
    Filed: August 26, 2003
    Date of Patent: July 10, 2007
    Assignee: Delphi Technologies, Inc.
    Inventors: Gabriel Gallegos-Lopez, Fani S. Gunawan, James E. Walters
  • Patent number: 6876169
    Abstract: Method for providing current regulation and a current controller (10) for an electric machine (30) are provided. The method includes receiving a state vector time signal (36) indicative of a time interval when a switching state vector is activated and comparing the received state vector time signal to a commanded state vector time signal (38). The method further includes using the result of the comparison to regulate a direct axis current signal (42, 44) input to an electric machine controller. The current controller (10) includes a state vector error comparator for comparing a received state vector time signal to a commanded state vector time signal and generating a state vector time error. This error is processed by a PI controller, coupled to the state vector error comparator, for providing a direct axis current signal output responsive to the state vector time error to an electric machine.
    Type: Grant
    Filed: January 14, 2003
    Date of Patent: April 5, 2005
    Assignee: Delphi Technologies, Inc.
    Inventors: Gabriel Gallegos-Lopez, James E. Walters, Fani S. Gunawan
  • Patent number: 6850033
    Abstract: A device to regulate current produced by an induction machine responsive to a plurality of phase current signals. The motor produces torque for application on a shaft. A processing and drive circuit responsive to a direct current command signal and a quadrature current command signal produces phase current signals for input to the motor. A command circuit responsive to the phase current signals, an angular position of said shaft, and a voltage input command signal to produce a direct current error signal and a quadrature current error signal. A control circuit responsive to the direct and quadrature current error signals produces the direct voltage signal command and the quadrature signal command. The control circuit has a direct and quadrature proportional gain, integrator and clamp circuits. An algorithm produces limited or clamped voltage modulation index signals to obtain maximum efficiency and maximum torque per ampere in the speed range.
    Type: Grant
    Filed: August 26, 2003
    Date of Patent: February 1, 2005
    Assignee: Delphi Technologies, Inc.
    Inventors: Gabriel Gallegos-Lopez, Fani S. Gunawan, James E. Walters
  • Publication number: 20040135538
    Abstract: Method for providing current regulation and a current controller (10) for an electric machine (30) are provided. The method includes receiving a state vector time signal (36) indicative of a time interval when a switching state vector is activated and comparing the received state vector time signal to a commanded state vector time signal (38). The method further includes using the result of the comparison to regulate a direct axis current signal (42, 44) input to an electric machine controller. The current controller (10) includes a state vector error comparator for comparing a received state vector time signal to a commanded state vector time signal and generating a state vector time error. This error is processed by a PI controller, coupled to the state vector error comparator, for providing a direct axis current signal output responsive to the state vector time error to an electric machine.
    Type: Application
    Filed: January 14, 2003
    Publication date: July 15, 2004
    Inventors: Gabriel Gallegos-Lopez, James E. Walters, Fani S. Gunawan
  • Patent number: 6741060
    Abstract: Method and system for controlling a permanent magnet machine driven by an inverter is provided. The method allows for monitoring a signal indicative of a fault condition. The method further allows for generating during the fault condition a respective signal configured to maintain a field weakening current even though electrical power from an energy source is absent during said fault condition. The level of the maintained field-weakening current enables the machine to operate in a safe mode so that the inverter is protected from excess voltage.
    Type: Grant
    Filed: April 5, 2001
    Date of Patent: May 25, 2004
    Assignee: Delphi Technologies, Inc.
    Inventors: Ronald John Krefta, James E. Walters, Fani S. Gunawan
  • Patent number: 6590361
    Abstract: Method and system for controlling an induction machine are provided. The method allows to sense rotor position of the induction machine using a relatively low-resolution rotor position sensor configured to supply a stream of pulses indicative of angular increments as the rotor position changes. A memory device is used for storing a synchronous angle boost function. The method further allows to retrieve from the memory device at least one function parameter for providing a synchronous angle boost during a start up mode of operation of the induction machine. Upon sensing a predetermined number of pulses from the rotor position sensor, the method allows to switch from the start up mode of operation to a normal mode of operation, wherein the boost provided to the synchronous angle is discontinued upon switching to the normal mode of operation.
    Type: Grant
    Filed: July 19, 2001
    Date of Patent: July 8, 2003
    Assignee: Delphi Technologies, Inc.
    Inventors: James E. Walters, Fani S. Gunawan, Gerald Thomas Fattic
  • Publication number: 20030015989
    Abstract: Method and system for controlling an induction machine are provided. The method allows to sense rotor position of the induction machine using a relatively low-resolution rotor position sensor configured to supply a stream of pulses indicative of angular increments as the rotor position changes. A memory device is used for storing a synchronous angle boost function. The method further allows to retrieve from the memory device at least one function parameter for providing a synchronous angle boost during a start up mode of operation of the induction machine. Upon sensing a predetermined number of pulses from the rotor position sensor, the method allows to switch from the start up mode of operation to a normal mode of operation, wherein the boost provided to the synchronous angle is discontinued upon switching to the normal mode of operation.
    Type: Application
    Filed: July 19, 2001
    Publication date: January 23, 2003
    Inventors: James E. Walters, Fani S. Gunawan, Gerald Thomas Fattic
  • Publication number: 20020145837
    Abstract: Method and system for controlling a permanent magnet machine driven by an inverter is provided. The method allows for monitoring a signal indicative of a fault condition. The method further allows for generating during the fault condition a respective signal configured to maintain a field weakening current even though electrical power from an energy source is absent during said fault condition. The level of the maintained field-weakening current enables the machine to operate in a safe mode so that the inverter is protected from excess voltage.
    Type: Application
    Filed: April 5, 2001
    Publication date: October 10, 2002
    Inventors: Ronald John Krefta, James E. Walters, Fani S. Gunawan
  • Patent number: 6407531
    Abstract: System and method for controlling a synchronous machine are provided. The method allows for calculating a stator voltage index. The method further allows for relating the magnitude of the stator voltage index against a threshold voltage value. An offset signal is generated based on the results of the relating step. A respective state of operation of the machine is determined. The offset signal is processed based on the respective state of the machine.
    Type: Grant
    Filed: January 9, 2001
    Date of Patent: June 18, 2002
    Assignee: Delphi Technologies, Inc.
    Inventors: James E. Walters, Fani S. Gunawan, Yanhong Xue