Patents by Inventor Mohammad N. Anwar

Mohammad N. Anwar 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: 20110109155
    Abstract: A method for avoiding electrical resonance in a vehicle having a high-voltage (HV) direct current (DC) bus shared by a first and a second power electronic converter device, such as an air conditioning compressor module (ACCM) and a traction power inverter (TPIM), includes determining an impedance characteristic of the bus, defining resonance points for the bus, selecting lower and upper switching frequency boundaries for the TPIM, and preventing the TPIM from operating within a range defined by these boundaries. A vehicle includes the first and second power electronic converter device, e.g., the APPM and the TPIM, the shared HV DC, and a controller having the algorithm set forth above, wherein the controller is adapted for avoiding electrical resonance in the HV DC bus by executing the algorithm.
    Type: Application
    Filed: November 9, 2009
    Publication date: May 12, 2011
    Applicant: GM GLOBAL TECHNOLGY OPERATIONS, INC.
    Inventors: Mohammad N. Anwar, Steven E. Schulz, Stephan N. Green, James E. Tarchinski
  • Publication number: 20110089883
    Abstract: A method of detecting a phase winding fault in a multi-phase electric machine is executable via a motor controller, and includes measuring feedback signals of the machine, including each phase current, and generating reference phase voltages for each phase. The method includes calculating a predetermined voltage value using the feedback signals and reference phase voltages, and comparing the voltage value to a corresponding threshold to determine the fault. A control action is executed when the voltage value exceeds the corresponding threshold. The voltage value is one or more of: a ratio of a normalized zero sequence voltage to a modulation index, an RMS voltage for each phase, and total harmonic distortion of each phase current. An apparatus detects the fault, and includes a motor controller and an algorithm as set forth above. The apparatus may include a voltage inverter for generating a multi-phase alternating current output for powering the machine.
    Type: Application
    Filed: October 21, 2009
    Publication date: April 21, 2011
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Mohammad N. Anwar, S.M. N. Hasan, Khwaja M. Rahman, Silva Hiti, Steven E. Schulz, Sean E. Gleason
  • Publication number: 20100320953
    Abstract: Systems and methods are provided for diagnosing stator windings in an electric motor operating under control of a current-regulating control loop. The current-regulating control loop is configured to provide a command voltage to the electric motor. The command voltage comprises a current-regulated voltage based on a difference between a commanded current and a measured current through the stator windings. The method comprises determining a negative sequence component of the command voltage, and identifying a fault condition when a characteristic of the negative sequence component is greater than a threshold value.
    Type: Application
    Filed: June 18, 2009
    Publication date: December 23, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: CHIA-CHOU YEH, STEVEN E. SCHULZ, MOHAMMAD N. ANWAR
  • Publication number: 20100244760
    Abstract: Methods and systems are provided for detecting loss of isolation of a motor, connections, or phase cables while an AC motor is operating. The system includes a power supply that is substantially isolated from the ground or chassis having a power supply voltage, and a power inverter electrically coupled to the power supply. The power inverter is configured to provide AC current from the power supply in an AC phase at an AC terminal, with the phase having current at a fundamental frequency that controls the motor speed. An electric motor is electrically coupled to the AC terminal of the power inverter and has a chassis that is substantially electrically isolated from the AC terminal of the power inverter under normal operating conditions. A processor is configured to control the AC current provided by the power inverter. The processor is configured to receive a first voltage signal related to current flowing through a motor chassis.
    Type: Application
    Filed: March 26, 2009
    Publication date: September 30, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Mohammad N. Anwar, Bryan M. Ludwig, S.M. N. Hasan, Sean E. Gleason, Bon Ho Bae
  • Publication number: 20100013438
    Abstract: Embodiments include a power processing system and methods of its operation in a plug-in electric vehicle. The power processing system includes at least one AC electric motor, a bi-directional inverter system, and an electronic control system. The electronic control system provides a drive function by providing first control signals to the bi-directional inverter system which, in response, draws DC electrical power from a DC energy source, converts the DC power to AC power, and provides the AC power to windings of the at least one AC electric motor. The electronic control system also provides a charging function by providing second control signals to the bi-directional inverter system which, in response, draws AC power from the windings of the at least one AC electric motor, converts the AC power to DC power, and provides the DC power to the DC energy source in order to recharge the DC energy source.
    Type: Application
    Filed: July 21, 2008
    Publication date: January 21, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Mohammad N. ANWAR, Erkan MESE
  • Patent number: 7576500
    Abstract: Methods and systems for operating a motor coupled to an electrical bus in a vehicle are provided. Selected resonant frequencies of the electrical bus are determined. The selected resonant frequencies include a low resonant frequency and a high resonant frequency. Power is provided to the motor through at least one switch operating at a switching frequency. The switching frequency is controlled as a function of a rate of operation of the motor. The function is characterized by one of a first substantially linear portion having a first slope when the switching frequency is less than or equal to a selected switching frequency and a second substantially linear portion having a second slope if the switching frequency is greater than the selected frequency, the selected switching frequency being greater than the low resonant frequency and a substantially linear portion having a y-intercept being greater than the low resonant frequency.
    Type: Grant
    Filed: May 31, 2007
    Date of Patent: August 18, 2009
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Nitinkumar R. Patel, Mohammad N. Anwar, Silva Hiti, Brian A Welchko, Steven E. Schulz, Lisa M. Talarico
  • Publication number: 20090115491
    Abstract: A hybrid powertrain system includes an engine, an electric machine, a power electronics device including a plurality of electric circuit layers, and a cooling system. A method for managing thermal energy in the power electronics device includes monitoring a plurality of temperature sensors in the power electronics device, monitoring electric power into and out of the power electronics device, predicting temperatures for the plurality of electric circuit layers, and controlling the hybrid powertrain system based upon the predicted temperatures for the plurality of electric circuit layers.
    Type: Application
    Filed: October 22, 2008
    Publication date: May 7, 2009
    Applicants: GM GLOBAL TECHNOLOGY OPERATIONS, INC., Daimler AG, Chrysler LLC, Byerishe Motoren Werke Aktiengesellschaft
    Inventors: Mohammad N. Anwar, Prakash Haribhai Desai, Sean E. Gleason, Brian A. Welchko
  • Publication number: 20080298785
    Abstract: Methods and systems for operating a motor coupled to an electrical bus in a vehicle are provided. Selected resonant frequencies of the electrical bus are determined. The selected resonant frequencies include a low resonant frequency and a high resonant frequency. Power is provided to the motor through at least one switch operating at a switching frequency. The switching frequency is controlled as a function of a rate of operation of the motor. The function is characterized by one of a first substantially linear portion having a first slope when the switching frequency is less than or equal to a selected switching frequency and a second substantially linear portion having a second slope if the switching frequency is greater than the selected frequency, the selected switching frequency being greater than the low resonant frequency and a substantially linear portion having a y-intercept being greater than the low resonant frequency.
    Type: Application
    Filed: May 31, 2007
    Publication date: December 4, 2008
    Inventors: Nitinkumar R. Patel, Mohammad N. Anwar, Silva Hiti, Brian A. Welchko, Steven E. Schulz, Lisa M. Talarico
  • Patent number: 7180212
    Abstract: An electric machine including multiple windings, a switch circuit connected to each of the windings, a positive bus bar, and a negative bus bar. The switch circuits are in communication with the windings to selectively energize each of the windings. The positive bus bar is a conductive plate connected to the switch circuits and the negative bus bar is a conductive plate positioned substantially parallel to the positive bus bar and connected electrically to the switch circuits.
    Type: Grant
    Filed: July 2, 2004
    Date of Patent: February 20, 2007
    Assignee: Visteon Global Technologies, Inc.
    Inventors: Mohammad N. Anwar, Mehrdad Teimor, Richard E. Luken, Jeffrey J. Brautigan
  • Patent number: 7030587
    Abstract: A system for controlling a switch reluctance machine is provided. The system includes multiple phases located in the switch reluctance machine, each phase having multiple machine coils. Each machine coil is independently connected to a positive side switch circuit and a negative side switch circuit. Each positive side switch circuit is in electrical parallel connection with the other positive side switch circuits, and configured to control the flow of current through the machine coil to which it is connected. Similarly, the negative side switch circuits are connected in electrical parallel and configured to control the flow of current through the machine coil to which they are connected. The positive side and negative side switch circuits may be provided in a buck boost configuration or two half bridge configurations.
    Type: Grant
    Filed: April 9, 2004
    Date of Patent: April 18, 2006
    Assignee: Visteon Global Technologies, Inc.
    Inventors: Mohammad N. Anwar, Mehrdad Teimor, Daryl A. Wilson, Paul F. Turnbull, William Turnbull