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: 20030107352
    Abstract: A power control system for an electric traction motor in a vehicle comprising at least one inverter for providing conditioned electrical power to the electric traction motor, a plurality of power stages for providing DC power to the at least one inverter, each stage including a battery and boost/buck DC-DC converter, the power stages wired in parallel, and where the power stages are controlled to maintain an output voltage to the at least one inverter.
    Type: Application
    Filed: December 6, 2001
    Publication date: June 12, 2003
    Inventors: Scott D. Downer, James F. Lazar, James M. Nagashima
  • Publication number: 20030048089
    Abstract: A method of generating low voltage auxiliary power forms for electric or hybrid vehicle use by tapping power from the traction motor primary winding with a secondary winding and rectifier.
    Type: Application
    Filed: September 7, 2001
    Publication date: March 13, 2003
    Inventors: Douglas S. Carlson, Constantin C. Stancu, James M. Nagashima, Silva Hiti, Khwaja M. Rahman
  • Patent number: 6504329
    Abstract: A control scheme for an surface-mounted permanent-magnet synchronous (SMPMS) drive uses a combination of an open-loop magnetizing current reference calculation and a stabilizing feedback term, which speeds-up the torque transient response. The feedback term increases the stability margin during torque transients by increasing the available voltage margin for current control. The magnetizing current reference calculation takes into account the saturation effects in the SMPMS drive, which occur at peak torque points, and compensates for them. By taking into account saturation effects, stable operation at high speed is achieved, thereby increasing the speed range of the SMPMS drive.
    Type: Grant
    Filed: April 9, 2001
    Date of Patent: January 7, 2003
    Assignee: General Motors Corporation
    Inventors: Constantin C. Stancu, Silva Hiti, James M. Nagashima
  • Publication number: 20020171387
    Abstract: A control scheme for an surface-mounted permanent-magnet synchronous (SMPMS) drive uses a combination of an open-loop magnetizing current reference calculation and a stabilizing feedback term, which speeds-up the torque transient response. The feedback term increases the stability margin during torque transients by increasing the available voltage margin for current control. The magnetizing current reference calculation takes into account the saturation effects in the SMPMS drive, which occur at peak torque points, and compensates for them. By taking into account saturation effects, stable operation at high speed is achieved, thereby increasing the speed range of the SMPMS drive.
    Type: Application
    Filed: April 9, 2001
    Publication date: November 21, 2002
    Applicant: General Motors Corporation
    Inventors: Constantin C. Stancu, Silva Hiti, James M. Nagashima
  • Patent number: 6404628
    Abstract: A power electronics cooling housing for use in a power electronics system. The power electronics cooling housing has a body with a coolant cavity formed in one surface and a capacitor bus assembly potting cavity formed in an opposite surface. A bus bar passthrough opening is formed through the body. The bus bar passthrough opening provides an opening from the coolant cavity and the capacitor bus assembly potting cavity. A coolant inlet manifold having a coolant cavity inlet and a coolant outlet manifold having a coolant cavity outlet are formed in the body that are coupled to respective ends of the coolant cavity. An environmental sealing gasket surrounds the coolant cavity.
    Type: Grant
    Filed: July 21, 2000
    Date of Patent: June 11, 2002
    Assignee: General Motors Corporation
    Inventors: James M. Nagashima, Terence G. Ward, Scott D. Downer
  • Patent number: 6313991
    Abstract: A thermally cooled power electronics system. A cooling housing has a body with a coolant cavity formed in one surface and a capacitor bus assembly potting cavity formed in an opposite surface. A bus bar passthrough opening is formed through the body, along with a coolant inlet and outlet manifolds having a coolant cavity inlet outlet that are coupled to respective ends of the coolant cavity. An environmental sealing gasket surrounds the coolant cavity. A plurality of laminated copper bus bars are disposed through the bus bar passthrough opening. A laminated horizontal bus bar assembly extends along the length of the housing above the coolant cavity and has horizontal bus bars that are coupled to the laminated copper bus bars. A battery input connector is coupled by way of a vertical bus bar assembly to the horizontal bus bar assembly. A plurality of power switching devices are coupled to the laminated horizontal bus bar assembly.
    Type: Grant
    Filed: July 24, 2000
    Date of Patent: November 6, 2001
    Assignee: General Motors Corporation
    Inventors: James M. Nagashima, Terence G. Ward, Scott D. Downer