Patents by Inventor Yifan Tang

Yifan Tang 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: 20100187905
    Abstract: A method and apparatus for an all-electric vehicle using a primary drive system and a secondary drive system is provided. While the primary drive system utilizes a single electric motor, the secondary drive system utilizes a pair of electric motors. In one configuration, a single electrical energy storage system (ESS) is used to supply power to both drive systems. A DC/DC converter can be used so that the two drive systems can utilize different DC bus voltage ranges. In another configuration, each drive system is coupled to a different electrical ESS. A bi-directional DC/DC converter can be used to provide an electrical path between each motor's inverter and the electrical ESS of the other drive system. An energy transfer control module connected to the bi-directional DC/DC converter and one or more sensors can be used to control the use of the bi-directional DC/DC converter.
    Type: Application
    Filed: February 19, 2009
    Publication date: July 29, 2010
    Applicant: Tesla Motors, Inc.
    Inventor: Yifan Tang
  • Publication number: 20100187024
    Abstract: A method and apparatus for an all-electric vehicle using a primary drive system and a secondary drive system is provided. The primary drive system and the secondary drive system each utilize a single electric motor. In one configuration, a single electrical energy storage system (ESS) is used to supply power to both drive systems. A DC/DC converter can be used so that the two drive systems can utilize different DC bus voltage ranges. In another configuration, each drive system is coupled to a different electrical ESS. A bi-directional DC/DC converter can be used to provide an electrical path between each motor's inverter and the electrical ESS of the other drive system. An energy transfer control module connected to the bi-directional DC/DC converter and one or more sensors can be used to control the use of the bi-directional DC/DC converter.
    Type: Application
    Filed: January 29, 2009
    Publication date: July 29, 2010
    Applicant: Tesla Motors, Inc.
    Inventor: Yifan Tang
  • Patent number: 7747363
    Abstract: A method and apparatus for optimizing the torque of the electric motor of an electric vehicle is provided, the torque adjustments taking into account wheel slip as well as other vehicular operating conditions.
    Type: Grant
    Filed: March 17, 2009
    Date of Patent: June 29, 2010
    Assignee: Tesla Motors, Inc.
    Inventor: Yifan Tang
  • Patent number: 7742852
    Abstract: A method and apparatus for optimizing the torque applied to the primary and assist drive systems of an all-electric vehicle is provided, the torque adjustments taking into account wheel slip as well as other vehicular operating conditions.
    Type: Grant
    Filed: March 17, 2009
    Date of Patent: June 22, 2010
    Assignee: Tesla Motors, Inc.
    Inventor: Yifan Tang
  • Patent number: 7741750
    Abstract: An induction motor embodiment includes a stator defining a stator bore, the stator including a stator yoke having a stator yoke thickness and a plurality of stator teeth, the teeth having a common length, with each of the stator teeth including a stator tooth center portion that extends from a stator tooth bottom portion proximal the yoke to a stator tooth tip portion, with adjacent stator teeth defining a stator slot between them, each stator slot having a stator slot bottom that extends along a stator slot bottom length. In the embodiment, the center portion has a stator tooth width that is less than or equal to one half the stator slot bottom length. In the embodiment, the stator tooth width is smaller than a stator slot opening width distance. In the embodiment, a ratio of stator yoke thickness to stator tooth width is at least 5:1. A rotor is rotably mounted in the stator.
    Type: Grant
    Filed: December 29, 2008
    Date of Patent: June 22, 2010
    Assignee: Tesla Motors, Inc.
    Inventor: Yifan Tang
  • Patent number: 7739005
    Abstract: A method and apparatus for optimizing the torque applied to the primary and assist drive systems of an all-electric vehicle is provided, the torque adjustments taking into account wheel slip as well as other vehicular operating conditions.
    Type: Grant
    Filed: February 26, 2009
    Date of Patent: June 15, 2010
    Assignee: Tesla Motors, Inc.
    Inventor: Yifan Tang
  • Publication number: 20100141080
    Abstract: An induction motor embodiment includes a stator defining a stator bore, the stator including a stator yoke having a stator yoke thickness and a plurality of stator teeth, the teeth having a common length, with each of the stator teeth including a stator tooth center portion that extends from a stator tooth bottom portion proximal the yoke to a stator tooth tip portion, with adjacent stator teeth defining a stator slot between them, each stator slot having a stator slot bottom that extends along a stator slot bottom length. In the embodiment, the center portion has a stator tooth width that is less than or equal to one half the stator slot bottom length. In the embodiment, the stator tooth width is smaller than a stator slot opening width distance. In the embodiment, a ratio of stator yoke thickness to stator tooth width is at least 5:1. A rotor is rotably mounted in the stator.
    Type: Application
    Filed: December 29, 2008
    Publication date: June 10, 2010
    Applicant: Tesla Motors, Inc.
    Inventor: Yifan Tang
  • Publication number: 20100133023
    Abstract: A method and apparatus for an all-electric vehicle using a primary drive system and a secondary drive system is provided. While the primary drive system utilizes a single electric motor, the secondary drive system utilizes a pair of electric motors. A single electrical energy storage system (ESS) is used to supply power to both drive systems. A DC/DC converter can be used so that the two drive systems can utilize different DC bus voltage ranges.
    Type: Application
    Filed: September 23, 2009
    Publication date: June 3, 2010
    Applicant: Tesla Motors, Inc.
    Inventor: Yifan Tang
  • Publication number: 20100090629
    Abstract: A motor in an electric vehicle can be controlled by receiving at least one of a user input or vehicle information, selecting one of a plurality of available flux modes using at least one of the user input or the vehicle information, and calculating a control signal, using the selected flux mode, to control the motor of the electric vehicle.
    Type: Application
    Filed: October 15, 2008
    Publication date: April 15, 2010
    Applicant: Tesla Motors, Inc.
    Inventor: Yifan Tang
  • Patent number: 6798606
    Abstract: Non-linearity in a position error signal (PES) for a data storage device is precisely characterized during a calibration phase in the manufacturing process. From this characterization of the PES non-linearity, the data storage device can be programmed with the necessary data to perform accurate, real-time linearization calculations of the PES in order to compensate for non-linearity in the PES during operation. The sequence of calibration steps includes a PES gain calibration, a first servo loop gain calibration, a PES linearization calibration, and an optional second servo loop gain calibration.
    Type: Grant
    Filed: January 22, 2002
    Date of Patent: September 28, 2004
    Assignee: International Business Machines Corporation
    Inventors: Yifan Tang, Craig N. Fukushima, Isao Yoneda, Hiroshi Uchida
  • Publication number: 20030137906
    Abstract: Non-linearity in a position error signal (PES) for a data storage device is precisely characterized during a calibration phase in the manufacturing process. From this characterization of the PES non-linearity, the data storage device can be programmed with the necessary data to perform accurate, real-time linearization calculations of the PES in order to compensate for non-linearity in the PES during operation. The sequence of calibration steps includes a PES gain calibration, a first servo loop gain calibration, a PES linearization calibration, and an optional second servo loop gain calibration.
    Type: Application
    Filed: January 22, 2002
    Publication date: July 24, 2003
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yifan Tang, Craig N. Fukushima, Isao Yoneda, Hiroshi Uchida
  • Patent number: 6078122
    Abstract: A reluctance machine including a plurality of phase windings where each phase winding comprises a plurality of fractional-pitched coils. The reluctance machine may be coupled to a drive that can energize one, two or more of the phase windings to provide output torque that is derived from: (i) the self-inductances of the phase windings; (ii) a combination of the self-inductances of the phase windings and the mutual inductances between the phase windings; or (iii) the mutual inductances between the phase windings.
    Type: Grant
    Filed: March 29, 1999
    Date of Patent: June 20, 2000
    Assignee: Emerson Electric Co.
    Inventors: Yifan Tang, Yue Li
  • Patent number: 6008561
    Abstract: A reluctance machine including one or more damping windings placed within the stator or within the rotor which are used to store and provide energy so as to reduce unwanted machine vibration and noise, improve current commutation, and improve the efficiency and torque output of the machine.
    Type: Grant
    Filed: October 31, 1996
    Date of Patent: December 28, 1999
    Assignee: Emerson Electric Co.
    Inventor: Yifan Tang
  • Patent number: 5929590
    Abstract: A doubly-fed switched reluctance machine in which at least two sets of phase winding are energized to produce desired output torque is disclosed. Also disclosed are dual and single power converters for energizing the doubly-fed machine as well as exemplary excitation schemes position. Sensorless techniques and systems for controlling the doubly-fed machine, and other machines having fully-pitched or fractional-pitched windings, are also disclosed.
    Type: Grant
    Filed: January 7, 1997
    Date of Patent: July 27, 1999
    Assignee: Emerson Electric Co.
    Inventor: Yifan Tang
  • Patent number: 5889347
    Abstract: A reluctance machine including a plurality of phase windings where each phase winding comprises a plurality of fractional-pitched coils. The reluctance machine may be coupled to a drive that can energize one, two or more of the phase windings to provide output torque that is derived from: (i) the self-inductances of the phase windings; (ii) a combination of the self inductances of the phase windings and the mutual inductances between the phase windings; or (iii) the mutual inductances between the phase windings.
    Type: Grant
    Filed: July 9, 1996
    Date of Patent: March 30, 1999
    Assignee: Emerson Electric Co.
    Inventors: Yifan Tang, Yue Li
  • Patent number: 5841262
    Abstract: A universal drive for a switched reluctance machine the drive obtaining a desired speed, the drive comprising means for automatically forming a magnetization table, said table containing information relating the magnetic flux, current, and rotor angle of said switched reluctance machine; means for automatically forming a rule table, the rule table containing information relating the torque of the SRM to turn-on and turn-off angles; sensors for sensing the dc bus voltage and currents of the phases of the machine; means for estimating a reference angle using information in the magnetization table and the sensed dc bus voltage and phase currents; means for obtaining the turn-on and turn-off angles from the self-tuned table based upon the desired speed; and means for turning the phase currents of the machine on at the turn-on angle in relation to the reference angle and turning the phase current off at the turn-off angle in relation to the reference angle.
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: November 24, 1998
    Assignee: Emerson Electric Co.
    Inventor: Yifan Tang
  • Patent number: 5838087
    Abstract: A reluctance machine including a stator defining a plurality of stator poles and a plurality of stator slots, a rotor positioned to rotate with respect to the stator, and a plurality of phase windings, where each phase winding comprises a plurality of coils, where each coil is wound about more than one stator pole, where each coil comprises two coils sides, and where only one coil side is positioned in each stator slot, wherein the self-inductance of each phase winding varies as a function of the angular position of the rotor with respect to the stator. Also a reluctance machine similar to that described above where each of the phase windings is magnetic uni-polar.
    Type: Grant
    Filed: August 30, 1996
    Date of Patent: November 17, 1998
    Assignee: Emerson Electric Co.
    Inventor: Yifan Tang
  • Patent number: 5811905
    Abstract: A doubly-fed switched reluctance machine in which at least two sets of phase winding are energized to produce desired output torque is disclosed. Also disclosed are dual and single power converters for energizing the doubly-fed machine as well as exemplary excitation schemes position. Sensorless techniques and systems for controlling the doubly-fed machine, and other machines having fully-pitched or fractional-pitched windings, are also disclosed.
    Type: Grant
    Filed: January 7, 1997
    Date of Patent: September 22, 1998
    Assignee: Emerson Electric Co.
    Inventor: Yifan Tang
  • Patent number: 5717269
    Abstract: An improved reluctance machine is provided wherein auxiliary flux paths are provided such that the leakage flux of the machine is directed through the auxiliary flux paths and not through the excited stator poles to reduce the impact of stator pole saturation on the machine's performance.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: February 10, 1998
    Assignee: Emerson Electric Co.
    Inventor: Yifan Tang