Patents by Inventor James M. Nagashima

James M. Nagashima 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: 20100134058
    Abstract: A method and system for operating an automotive electric motor having first and second components is provided. A desired frequency of vibration for the electric motor is selected. A current is caused to flow through at least one of the first and second components such that the second component moves relative to the first component. The current is modulated such that the motor vibrates at the desired frequency.
    Type: Application
    Filed: December 2, 2008
    Publication date: June 3, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: JAMES M. NAGASHIMA, STEVEN E. SCHULZ, YO CHAN SON, JONAS BEREISA
  • Patent number: 7723874
    Abstract: Cooling systems and methods are provided for an integrated electric motor-inverter, where the integrated electric motor-inverter includes a housing, a motor, and an inverter, the motor and the inverter are disposed within the housing, and the motor includes a stator. The system includes a cooling jacket, a first coolant, a condenser, a spray head, and a second coolant. The cooling jacket is disposed concentric to the stator and includes an inner wall and an outer wall. The inner wall is in direct contact with the stator. The first coolant is disposed between the cooling jacket inner and outer walls. The condenser is disposed concentric to the cooling jacket. The spray head is disposed adjacent the inverter. The second coolant is in flow communication with the spray head.
    Type: Grant
    Filed: February 15, 2008
    Date of Patent: May 25, 2010
    Assignee: GM Global Technology Operations, Inc.
    Inventors: George R. Woody, Karl D. Conroy, James M. Nagashima, David F. Nelson, Eric R. Ostrom, Gregory S. Smith
  • Publication number: 20100090625
    Abstract: An automotive system includes an electric motor, a direct current (DC) power supply coupled to the electric motor, a power converter including at least one conversion switch coupled between the electric motor and the DC power supply and a braking circuit coupled between the electric motor and the DC power supply, the braking circuit including a braking resistor and a braking switch, and a controller in operable communication with the electric motor, the DC power supply, the at least one conversion switch, and the braking switch. The controller is configured to operate the at least one conversion switch when the electric motor is mechanically actuated such that current flows from the electric motor to the DC power supply and selectively operate the braking switch when a braking parameter of the automotive system exceeds a predetermined threshold.
    Type: Application
    Filed: October 9, 2008
    Publication date: April 15, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: JAMES M. NAGASHIMA, BRIAN A. WELCHKO
  • Patent number: 7605497
    Abstract: Systems and methods are disclosed for a two-source inverter. The systems and methods combines operation of a first voltage source powering a conventional single source inverter with second voltage source powering a novel switch configuration to power a load. The switch configuration is controlled by a plurality of control signals generated by controller based on a variety of control modes, and feedback signals.
    Type: Grant
    Filed: June 8, 2007
    Date of Patent: October 20, 2009
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Gabriel Gallegos-Lopez, James M. Nagashima, Silva Hiti
  • Publication number: 20090230900
    Abstract: Methods and systems are provided for controlling an AC motor via an inverter. The method includes determining a delay-compensated offset based on a synchronous frame current, producing a current error based on a synchronous frame current and a commanded current, producing a voltage error based on an anti-windup offset and the current error, producing a commanded voltage based on the delay-compensated offset and the voltage error, and providing the inverter with the commanded voltage.
    Type: Application
    Filed: March 13, 2008
    Publication date: September 17, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: BONHO BAE, NITINKUMAR R. PATEL, STEVEN E. SCHULZ, JAMES M. NAGASHIMA, JUNG SIK YIM, SEUNG KI SUL
  • Patent number: 7579792
    Abstract: An electrical system for a vehicle includes a power source providing electrical power to a first and a second electrical motor. Each motor has two or more windings, and each winding has a first end and a second end. A boost link such as a battery or capacitor is configured to store electrical energy for subsequent retrieval and use by either electrical motor. A first inverter circuit includes a first grouping of switches, wherein each of the first group of switches couples one of the first ends of the windings to the power source. A second inverter circuit includes a second group of switches, each coupling one of the second ends of the windings to the boost link. A controller is coupled to activate each of the first and second groups of switches to thereby allow the electrical energy to be placed on and retrieved from the boost link.
    Type: Grant
    Filed: April 23, 2007
    Date of Patent: August 25, 2009
    Assignee: GM Global Technology Operations, Inc.
    Inventors: James M. Nagashima, Brian A Welchko, Peter J. Savagian
  • Publication number: 20090206687
    Abstract: Cooling systems and methods are provided for an integrated electric motor-inverter, where the integrated electric motor-inverter includes a housing, a motor, and an inverter, the motor and the inverter are disposed within the housing, and the motor includes a stator. The system includes a cooling jacket, a first coolant, a condenser, a spray head, and a second coolant. The cooling jacket is disposed concentric to the stator and includes an inner wall and an outer wall. The inner wall is in direct contact with the stator. The first coolant is disposed between the cooling jacket inner and outer walls. The condenser is disposed concentric to the cooling jacket. The spray head is disposed adjacent the inverter. The second coolant is in flow communication with the spray head.
    Type: Application
    Filed: February 15, 2008
    Publication date: August 20, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: George R. WOODY, Karl D. CONROY, James M. NAGASHIMA, David F. NELSON, Eric R. OSTROM, Gregory S. SMITH
  • Patent number: 7525269
    Abstract: Methods and apparatus are provided for generating zero-sequence voltages based on voltage commands and a motor output signal. At least one of the methods includes, but is not limited to, receiving a torque command and generating three-phase voltage commands based on the torque command. The method also includes, but is not limited to, generating a motor output responsive to the three-phase voltage commands and generating three-phase zero-sequence voltage samples based on the three-phase voltage commands and the motor output.
    Type: Grant
    Filed: December 14, 2005
    Date of Patent: April 28, 2009
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Nitinkumar R. Patel, Bon-Ho Bae, James M. Nagashima
  • Patent number: 7521905
    Abstract: Apparatus, systems, and methods are provided for reducing a potentially damaging high voltage fault condition in an alternator system. The apparatus comprises a motor, a rectifier coupled to the motor, an output node coupled to the rectifier, and a switch coupled between the rectifier and the output node, wherein the switch is a normally “on” switch. The system includes the apparatus implemented into a vehicle comprising an engine to drive the apparatus and a battery coupled to the apparatus, wherein the apparatus provides current to the battery. The method includes the steps of providing current from a rectifier of the alternator to a battery coupled to the rectifier and ceasing to provide current to the battery if a damaging event occurs, wherein the ceasing step comprises the step of switching OFF a normally “on” switch coupled between the rectifier and the battery if a damaging event occurs.
    Type: Grant
    Filed: September 13, 2006
    Date of Patent: April 21, 2009
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Brian Welchko, Gregory S. Smith, James M. Nagashima
  • Publication number: 20090033255
    Abstract: Systems and methods are provided for charging energy sources with a rectifier using a double-ended inverter system. An apparatus is provided for an electric drive system for a vehicle. The electric drive system comprises an electric motor configured to provide traction power to the vehicle. A first inverter is coupled to the electric motor and is configured to provide alternating current to the electric motor. A first energy source is coupled to the first inverter, wherein the first inverter is configured to provide power flow between the first energy source and the electric motor. A second inverter is coupled to the electric motor and is configured to provide alternating current to the electric motor. A rectifier is coupled to the second inverter and configured to produce a direct current output. The second inverter is configured to provide power from the rectifier to the electric motor.
    Type: Application
    Filed: June 10, 2008
    Publication date: February 5, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: George JOHN, Sibaprasad CHAKRABARTI, Brian A. WELCHKO, Gregory S. SMITH, James M. NAGASHIMA, Milun PERISIC
  • Publication number: 20090033156
    Abstract: Systems and methods are provided for controlling a double-ended inverter system coupled to a first energy source and a second energy source. The method comprises determining a constant power line associated with operation of the double-ended inverter system, the constant power line representing a desired power flow to the second energy source. The method further comprises determining an operating point on the constant power line, the operating point producing a minimum power loss in the double-ended inverter system for a required output current, and modulating the double-ended inverter system using a first voltage command and a second voltage command corresponding to the operating point.
    Type: Application
    Filed: April 21, 2008
    Publication date: February 5, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Sibaprasad Chakrabarti, Gregory S. Smith, James M. Nagashima, Brian A. Welchko, Milun Perisic, George John
  • Publication number: 20090034310
    Abstract: A terminal assembly for a power converter is provided. The terminal assembly includes first and second conductive components and a current sensor. The first conductive component has first and second releasable attachment formations. The second conductive component has first and second portions with respective first and second widths. The first width is less than the second width. The first portion is releasably attached to the first conductive component with the second releasable attachment formation. The current sensor has an opening therethrough and is positioned between the first conductive component and the second portion of the second conductive component such that the first portion of the first conductive component extends through the opening. The current sensor is responsive to current flowing through the first portion of the second conductive component.
    Type: Application
    Filed: July 24, 2008
    Publication date: February 5, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Terence G. WARD, George JOHN, Edward P. YANKOSKI, Gregory S. SMITH, James M. NAGASHIMA
  • Publication number: 20090032319
    Abstract: Systems and methods are provided for a double-ended inverter drive system for a fuel cell vehicle. An electric drive system for a vehicle comprises an electric motor configured to provide traction power to the vehicle. A first inverter is coupled to the electric motor, and is configured to provide alternating current to the electric motor. A fuel cell is coupled to the first inverter to provide power flow from the fuel cell to the electric motor. A second inverter is coupled to the electric motor, and is configured to provide alternating current to the electric motor. An energy source is coupled to the second inverter to provide power flow between the energy source and the electric motor. A controller is coupled to the first inverter and the second inverter, and is configured to provide a constant power from the fuel cell during operation of the electric motor.
    Type: Application
    Filed: June 19, 2008
    Publication date: February 5, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: James M. Nagashima, Gregory S. Smith, Brian A Welchko, Sibaprasad Chakrabarti, Milun Perisic, George John
  • Publication number: 20090033253
    Abstract: An electric traction system for a vehicle having a high voltage battery and a low voltage battery is provided. The system includes an AC electric motor and a double ended inverter system coupled to the AC electric motor. The AC electric motor has a first set of windings and a second set of windings that occupy common stator slots, where the first set of windings and the second set of windings are electrically isolated from each other. The double ended inverter system drives the AC electric motor using energy obtained from the high voltage battery and energy obtained from the low voltage battery. The double ended inverter system utilizes a first inverter subsystem coupled between the first set of windings and the high voltage battery, and a second inverter subsystem coupled between the second set of windings and the low voltage battery.
    Type: Application
    Filed: May 15, 2008
    Publication date: February 5, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: James M. NAGASHIMA, Brian A. WELCHKO, George JOHN, Sibaprasad CHAKRABARTI, Milun PERISIC, Gregory S. SMITH
  • Publication number: 20090034308
    Abstract: A double ended inverter system suitable for use with an AC electric traction motor of a vehicle is provided. The double ended inverter system cooperates with a first DC energy source and a second DC energy source, which may have different nominal voltages. The double ended inverter system includes an impedance source inverter subsystem configured to drive the AC electric traction motor using the first energy source, and an inverter subsystem configured to drive the AC electric traction motor using the second energy source. The double ended inverter system also utilizes a controller coupled to the impedance source inverter subsystem and to the inverter subsystem. The controller is configured to control the impedance source inverter subsystem and the inverter subsystem in accordance with a boost operating mode, a traditional inverter operating mode, and a recharge operating mode of the double ended inverter system.
    Type: Application
    Filed: June 3, 2008
    Publication date: February 5, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Brian A. WELCHKO, James M. NAGASHIMA, Gregory S. SMITH, Sibaprasad CHAKRABARTI, Milun PERISIC, George JOHN
  • Publication number: 20090033410
    Abstract: A power switch apparatus includes a substrate; a semiconductor die mounted on the substrate and including power electronics circuitry for a high power, alternating current motor application; gate drive circuitry mounted on the substrate and electrically coupled to the power electronics circuitry on the semiconductor die; and control circuitry mounted on the substrate and electrically coupled to the gate drive circuitry.
    Type: Application
    Filed: July 23, 2008
    Publication date: February 5, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: David F. NELSON, George JOHN, Gregory S. SMITH, David TANG, James M. NAGASHIMA, Gabriel GALLEGOS-LOPEZ
  • Publication number: 20090033254
    Abstract: A double ended inverter system for an AC traction motor of a vehicle includes a fuel cell configured to provide a DC voltage, an impedance source inverter subsystem coupled to the fuel cell, a DC voltage source, and an inverter subsystem coupled to the DC voltage source. The impedance source inverter subsystem, which includes an ultracapacitor, is configured to drive the AC traction motor. The inverter subsystem is configured to drive the AC electric traction motor. The ultracapacitor is implemented in a crossed LC network coupled to the fuel cell.
    Type: Application
    Filed: June 3, 2008
    Publication date: February 5, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: James M. NAGASHIMA, Brian A. WELCHKO, Sibaprasad CHAKRABARTI, Milun PERISIC, Gregory S. SMITH, George JOHN
  • Publication number: 20090033252
    Abstract: A double ended inverter system for an AC electric traction motor of a vehicle is disclosed. The inverter system serves as an interface between two different energy sources having different operating characteristics. The inverter system includes a first energy source having first operating characteristics associated therewith, and a first inverter subsystem coupled to the first energy source and configured to drive the AC electric traction motor. The inverter system also includes a second energy source having second operating characteristics associated therewith, wherein the first operating characteristics and the second operating characteristics are different, and a second inverter subsystem coupled to the second energy source and configured to drive the AC electric traction motor. In addition, the inverter system has a controller coupled to the first inverter subsystem and to the second inverter subsystem.
    Type: Application
    Filed: April 28, 2008
    Publication date: February 5, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Gregory S. Smith, Brian A. Welchko, George John, Sibaprasad Chakrabrarti, Milun Perisic, James M. Nagashima
  • Publication number: 20090033274
    Abstract: Systems and apparatus are provided for an inverter system for use in a vehicle having a first energy source and a second energy source. The inverter system comprises an electric motor having a first set of windings and a second set of windings. The inverter system further comprises a first inverter coupled to the first energy source and adapted to drive the electric motor, wherein the first set of windings are coupled to the first inverter. The inverter system also comprises a second inverter coupled to the second energy source and adapted to drive the electric motor, wherein the second set of windings are coupled to the second inverter. A controller is coupled to the first inverter and the second inverter to achieve desired power flow between the first energy source, the second energy source, and the electric motor.
    Type: Application
    Filed: April 28, 2008
    Publication date: February 5, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Milun PERISIC, Silva HITI, Brian A. WELCHKO, Sibaprasad CHAKRABARTI, James M. NAGASHIMA, Gregory S. SMITH, George JOHN
  • Publication number: 20090032316
    Abstract: Systems and methods are provided for an inverter system for use in a vehicle having a first energy source and a second energy source. The system comprises a motor having a first set of windings and a second set of windings. The first set of windings is electrically isolated from the second set of windings. The system further comprises a first inverter coupled to the first energy source and adapted to drive the motor, wherein the first set of windings are coupled to the first inverter. The system also comprises a second inverter coupled to the second energy source and adapted to drive the motor, wherein the second set of windings are coupled to the second inverter. A controller is coupled to the first inverter and the second inverter.
    Type: Application
    Filed: April 21, 2008
    Publication date: February 5, 2009
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Sibaprasad Chakrabarti, Gregory S. Smith, James M. Nagashima, Brian A. Welchko, Milun Perisic, George John