Patents by Inventor Brian A Welchko

Brian A Welchko 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: 20080116840
    Abstract: A method for controlling an inverter uses sequences of predetermined states where each state uniquely corresponding to a set of control signals provided to the inverter that is coupled to a motor. The method includes repeatedly applying a first center null timing sequence of the states while monitoring a zero crossing condition and then changing the repeated application of the first center null timing sequence of the states into a repeated application of a second center null timing sequence of states when the monitoring detects a zero crossing condition. The repeated application of the first center null timing sequence sequentially provides the inverter with a first predetermined sequence of sets of control signals. The monitoring of a zero crossing condition monitors for a zero crossing condition in an electrical current flowing between the inverter and a terminal of the motor. The second center null timing sequence defines a second predetermined sequence of sets of control signals.
    Type: Application
    Filed: November 20, 2006
    Publication date: May 22, 2008
    Inventors: Brian Welchko, Steven E. Schulz, Silva Hiti, Stephen T. West
  • Publication number: 20080094023
    Abstract: A method for controlling an alternating current (AC) motor includes choosing a pulse sequence based on a ripple current in the AC motor at a sampling instant; and providing a voltage to the AC motor based on the pulse sequence.
    Type: Application
    Filed: August 4, 2006
    Publication date: April 24, 2008
    Inventors: Stephen T. West, Brian Welchko, Steven E. Schulz, Silva Hiti
  • Publication number: 20080074088
    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: Application
    Filed: September 13, 2006
    Publication date: March 27, 2008
    Inventors: Brian Welchko, Gregory S. Smith, James M. Nagashima
  • Patent number: 7307401
    Abstract: PWM methods and apparatus are provided for loss minimized control of AC motors taking into consideration inverter non-linear limitations. The method comprises providing a voltage to the AC motor based on a switching cycle, adding a duty cycle of a zero vector to each phase leg of the switching cycle when a duty cycle of a first phase leg of the switching cycle is less than a minimum duty cycle, and subtracting the duty cycle of the zero vector from each phase leg of the switching cycle when a second duty cycle of a second phase leg is greater than a maximum duty cycle. The minimum duty cycle and maximum duty cycle indicate distortion regions.
    Type: Grant
    Filed: March 16, 2006
    Date of Patent: December 11, 2007
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Slobodan Gataric, Brian Welchko, Steven E. Schulz, Silva Hiti, Steve T. West
  • Publication number: 20070273223
    Abstract: Alternating current motors used to drive wheels of hybrid or fuel cell vehicles have capacitors which are mounted diametrically on the motors, i.e., mounted around the diameter of the motors. The capacitors may be annular or arcuate in shape. By so configuring the power capacitors, axial space adjacent to the motors is reduced, providing enhanced design flexibility for automotive vehicles.
    Type: Application
    Filed: May 25, 2006
    Publication date: November 29, 2007
    Inventors: Terence G. Ward, Alex Thompson, Brian Welchko
  • Patent number: 7286375
    Abstract: Methods and apparatus are provided for compensating for a deviation in voltage output of a phase leg inverter when dead-time periods are inserted to prevent shoot-through failures. The method includes determining a pulse width for an input signal to the inverter such that the inverter voltage output is a desired amount. The pulse width is based on the non-inverted or inverted pulse sequences of two carrier signals and the polarity of current through the inverter. An amount of pulse width is added to the input signal when the current is positive, and an amount of pulse width is subtracted from the input signal when the current is negative. An additional amount of pulse width is added to or subtracted from the input signal depending on whether the carrier signal sequence changes from a non-inverted signal to an inverted signal or changes from an inverted signal to a non-inverted signal, respectively.
    Type: Grant
    Filed: January 23, 2007
    Date of Patent: October 23, 2007
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Brian A Welchko, Silva Hiti, Steven E. Schulz
  • Patent number: 7279862
    Abstract: An apparatus includes a multi-phase inverter, a fault detector to indicate a detection of a fault, a sensor to provide a speed signal indicative of whether a speed of a PM motor is greater than a transition speed, and a controller. The controller is operable to apply either an open-circuit response or a short-circuit response to the multi-phase inverter. The open-circuit response is applied when the speed of the PM motor is greater than the transition speed and a fault is detected. The short-circuit response is applied when the speed of the PM motor is less than the transition speed and the fault is detected. The transition speed is either a fixed predetermined speed or an adjusted predetermined speed.
    Type: Grant
    Filed: August 4, 2006
    Date of Patent: October 9, 2007
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Brian Welchko, Jonathan B Huse, Silva Hiti, Brendan M. Conlon, Constantin C. Stancu, Khwaja M. Rahman, David Tang, William R. Cawthorne
  • Publication number: 20070228862
    Abstract: An armature for use in an electric traction motor comprises a rotor having a central portion and a peripheral portion with the peripheral portion having a plurality of cavities. Permanent magnets solidified from liquid magnetic material are disposed in the cavities to form poles of the rotor with at least a portion of the cavities having directly abutting permanent magnets comprised of at least first and second magnetic materials of different properties injected in liquid or mobile form into single cavities. In interface regions between the at least first and second magnetic materials the first and second magnetic materials are intermingled to form a transition zone. A method of making the armature includes injecting the magnetic materials simultaneously as well as injecting a subsequent magnetic material when the initial magnetic material is still fluidly mobile.
    Type: Application
    Filed: March 29, 2006
    Publication date: October 4, 2007
    Inventors: Brian Welchko, Constantin Stancu, Gregory Smith
  • Publication number: 20070216341
    Abstract: PWM methods and apparatus are provided for loss minimized control of AC motors taking into consideration inverter non-linear limitations. The method comprises providing a voltage to the AC motor based on a switching cycle, adding a duty cycle of a zero vector to each phase leg of the switching cycle when a duty cycle of a first phase leg of the switching cycle is less than a minimum duty cycle, and subtracting the duty cycle of the zero vector from each phase leg of the switching cycle when a second duty cycle of a second phase leg is greater than a maximum duty cycle. The minimum duty cycle and maximum duty cycle indicate distortion regions.
    Type: Application
    Filed: March 16, 2006
    Publication date: September 20, 2007
    Inventors: Slobodan Gataric, Brian Welchko, Steven Schulz, Silva Hiti, Steve West
  • Publication number: 20070216344
    Abstract: A dynamic pulse width modulation (PWM) selection device automatically switches between discontinuous PWM (DPWM) control methods. The PWM selection device comprises a PWM control module. The PWM control module determines a desired pulse width of a switching control signal according to a desired output signal. The PWM control module controls an actual pulse width of the switching control signal according to the desired pulse width and a first PWM control method. A selection module determines whether the desired pulse width exceeds a pulse width threshold. The selection module selects a second PWM control method when the desired pulse width exceeds the pulse width threshold.
    Type: Application
    Filed: March 16, 2006
    Publication date: September 20, 2007
    Inventors: Brian Welchko, Steven Schulz, Silva Hiti
  • Publication number: 20070133242
    Abstract: Methods and apparatus are provided for modifying a pulse width modulation signal controlling a voltage source inverter. The method comprises the steps of determining a duty cycle of the signal, clipping the duty cycle when a modulation index is greater than a minimum modulation index and less than a maximum modulation index, clipping the duty cycle when the modulation index is greater than or equal to the maximum modulation index, and transmitting the duty cycle to the voltage source inverter. The minimum modulation index indicates a distortion range.
    Type: Application
    Filed: December 14, 2005
    Publication date: June 14, 2007
    Inventors: Brian Welchko, Steven Schulz, Silva Hiti
  • Patent number: 7218071
    Abstract: Methods and apparatus are provided for controlling AC motor torque output. The method comprises the steps of producing a current based on a first comparison of a fundamental output frequency of the AC motor with a predetermined frequency and a second comparison of a magnitude of a commanded current with a predetermined DC current, and supplying the current to the AC motor.
    Type: Grant
    Filed: March 14, 2006
    Date of Patent: May 15, 2007
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Brian Welchko, Steven E. Schulz, Silva Hiti
  • Patent number: 7199535
    Abstract: A double-ended inverter system for a vehicle having a load, a first energy source, and a first inverter system coupled to the first energy source and adapted to drive the load. The double-ended inverter system further having a secondary energy source, a second capacitor coupled in parallel to the secondary energy source, and a second inverter system coupled to the secondary energy source and adapted to drive the load. A controller includes an output coupled to the first inverter system and the second inverter system for providing at least one pulse width modulated signal to the first inverter system and the second inverter system.
    Type: Grant
    Filed: January 26, 2005
    Date of Patent: April 3, 2007
    Assignee: General Motors Corporation
    Inventors: Brian Welchko, James M. Nagashima
  • Patent number: 7193378
    Abstract: A circuit for controlling a multi-phase machine having a stator with stator windings includes a controller, primary commutation switch pairs, a neutral terminal, and commutation control switches. Each switch pair includes first and second primary commutation switches connected at a node. Each commutation control switch is coupled to a winding so that a stator winding circuit is formed between the neural terminal and a respective one of the nodes. Each commutation control switch includes a first diode connected in parallel with a series switch circuit. Each series switch circuit includes a second diode and a series connected switch element. The controller is coupled to the switch elements and the primary commutation switch pairs to control an on time and an off time of the primary commutation switches relative to a point where a supply voltage is equal to the back emf.
    Type: Grant
    Filed: March 14, 2006
    Date of Patent: March 20, 2007
    Assignee: GM Global Technology Operations, Inc.
    Inventor: Brian Welchko
  • Patent number: 7154237
    Abstract: A method of providing a unified power control of a motor including providing a first inverter system, a second inverter system, and a motor coupled therebetween; coupling the first inverter system coupled to a first energy source; coupling the second inverter system coupled to a secondary energy source; generating a first pulse width modulated signal; and generating a second pulse width modulated signal. The first inverter system and the second inverter system are driven with the first pulse width modulated signal and the second pulse width modulated signal respectively in order to control a fundamental component of an output voltage of the first inverter system and the second inverter system to control the motor.
    Type: Grant
    Filed: January 26, 2005
    Date of Patent: December 26, 2006
    Assignee: General Motors Corporation
    Inventors: Brian Welchko, James M. Nagashima
  • Publication number: 20060164027
    Abstract: A method of providing a unified power control of a motor including providing a first inverter system, a second inverter system, and a motor coupled therebetween; coupling the first inverter system coupled to a first energy source; coupling the second inverter system coupled to a secondary energy source; generating a first pulse width modulated signal; and generating a second pulse width modulated signal. The first inverter system and the second inverter system are driven with the first pulse width modulated signal and the second pulse width modulated signal respectively in order to control a fundamental component of an output voltage of the first inverter system and the second inverter system to control the motor.
    Type: Application
    Filed: January 26, 2005
    Publication date: July 27, 2006
    Inventors: Brian Welchko, James Nagashima
  • Publication number: 20060164028
    Abstract: A double-ended inverter system for a vehicle having a load, a first energy source, and a first inverter system coupled to the first energy source and adapted to drive the load. The double-ended inverter system further having a secondary energy source, a second capacitor coupled in parallel to the secondary energy source, and a second inverter system coupled to the secondary energy source and adapted to drive the load. A controller includes an output coupled to the first inverter system and the second inverter system for providing at least one pulse width modulated signal to the first inverter system and the second inverter system.
    Type: Application
    Filed: January 26, 2005
    Publication date: July 27, 2006
    Inventors: Brian Welchko, James Nagashima
  • Patent number: 7057371
    Abstract: A hybrid/electric vehicle including a battery system connected to a DC charger, an inverter coupled to the battery system, and an electric AC motor coupled to the inverter. The motor has first, second and third stator windings corresponding to first, second and third phases of the motor. Each stator winding has first and second leads, and the inverter has a plurality of switches that are connected to provide current to the stator windings at the first and second leads.
    Type: Grant
    Filed: April 19, 2004
    Date of Patent: June 6, 2006
    Assignee: General Motors Corporation
    Inventors: Brian Welchko, James M. Nagashima, Khwaja M. Rahman
  • Publication number: 20050231152
    Abstract: A hybrid/electric vehicle including a battery system connected to a DC charger, an inverter coupled to the battery system, and an electric AC motor coupled to the inverter. The motor has first, second and third stator windings corresponding to first, second and third phases of the motor. Each stator winding has first and second leads, and the inverter has a plurality of switches that are connected to provide current to the stator windings at the first and second leads.
    Type: Application
    Filed: April 19, 2004
    Publication date: October 20, 2005
    Inventors: Brian Welchko, James Nagashima, Khwaja Rahman
  • Patent number: 6864646
    Abstract: A multiple inverter system is powered from a common energy source such as a battery. First and second inverters are coupled to the common energy source and drive corresponding motors. First and second controllers provide pulse width modulated signals, modulated with respect to first and second clock signals, respectively, to the respective first and second inverters. A capacitor coupled between a power bus and a ground bus smoothes power bus ripples caused by simultaneous switching. To reduce the size needed for the capacitor, different modulation schemes, such as center based interleaved, and leading and lagging edge coincident, are used when both motors are in the motoring mode or both motors are in the regeneration mode. However, the same modulation scheme is used when one motor is in the motoring mode and the other motor is in the regeneration mode.
    Type: Grant
    Filed: February 14, 2003
    Date of Patent: March 8, 2005
    Assignee: General Motors Corporation
    Inventors: Khwaja M. Rahman, Silva Hiti, Scott D. Downer, Brian Welchko