Patents by Inventor Constantin C. Stancu

Constantin C. Stancu 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).

  • Patent number: 10283475
    Abstract: A power module assembly has a first substrate including a first layer, second layer and a third layer. The first layer is configured to carry a switch current flowing in a first direction. A second substrate is operatively connected to the first substrate and includes a fourth layer, fifth layer and a sixth layer. A conductive joining layer connects the third layer of the first substrate and the fourth layer of the second substrate. The conductive joining layer may be a first sintered layer. The third layer of the first substrate, the first sintered layer and the fourth layer of the second substrate are configured to function together as a unitary conducting layer carrying the switch current in a second direction substantially opposite to the first direction. The net inductance is reduced by a cancellation effect of the switch current going in opposite directions.
    Type: Grant
    Filed: December 14, 2016
    Date of Patent: May 7, 2019
    Assignee: GM Global Technology Operations LLC
    Inventors: Terence G. Ward, Constantin C. Stancu, Marko Jaksic
  • Patent number: 10171021
    Abstract: Methods may involve determining a minimum voltage for a voltage command. A maximum voltage for the voltage command may be determined. A first representation of a first performance curve corresponding to the minimum voltage may be determined. A second representation of a second performance curve corresponding to the maximum voltage may be determined. An operating point to be achieved through the voltage command may be obtained. An evaluation may be made of whether the operating point lies between the first and second representations. When the operating point lies between the first and second representations, an interpolation may be conducted between the first and second representations to determine a magnitude of the voltage command.
    Type: Grant
    Filed: April 4, 2017
    Date of Patent: January 1, 2019
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Xin Jing, Brian A. Welchko, Constantin C. Stancu
  • Patent number: 10164563
    Abstract: An electric power system for supplying power to a permanent magnet electric machine includes a high-voltage DC power source that is disposed to supply electric power to a front-end converter connected via a high-voltage DC bus to an electric inverter that is connected to the electric machine. A method for operating a control system includes monitoring the electric machine. Upon detecting a fault associated with the electric machine, a controller commands operation of the front-end converter to generate a voltage level on the high-voltage DC bus that is a maximum setpoint voltage level and monitors back-emf voltage level from the electric machine. The inverter is controlled to a three-phase open state when the back-emf voltage level is less than the maximum setpoint voltage level. The inverter is controlled to a three-phase short state when the back-emf voltage level is greater than the maximum setpoint voltage level.
    Type: Grant
    Filed: April 15, 2016
    Date of Patent: December 25, 2018
    Assignee: GM Global Technology Operations LLC
    Inventors: Xin Jing, Brian A. Welchko, Constantin C. Stancu
  • Patent number: 10116174
    Abstract: A synchronous reluctance electric machine is described, and includes a stator including a plurality of electrical windings and a rotor disposed in a cylindrically-shaped void formed within the stator. The rotor includes a plurality of steel laminations assembled onto a shaft, wherein the shaft defines a longitudinal axis. Each of the steel laminations includes a plurality of poles and each of the poles includes a plurality of slots disposed near an outer periphery. The slots of the steel laminations are longitudinally aligned. A plurality of packets assembled from anisotropic material are disposed in the slots.
    Type: Grant
    Filed: May 4, 2016
    Date of Patent: October 30, 2018
    Assignee: GM Global Technology Operations LLC
    Inventors: Constantin C. Stancu, Peter J. Savagian, Khwaja M. Rahman, Nitinkumar R. Patel, Robert T. Dawsey
  • Publication number: 20180287540
    Abstract: Methods may involve determining a minimum voltage for a voltage command. A maximum voltage for the voltage command may be determined. A first representation of a first performance curve corresponding to the minimum voltage may be determined. A second representation of a second performance curve corresponding to the maximum voltage may be determined. An operating point to be achieved through the voltage command may be obtained. An evaluation may be made of whether the operating point lies between the first and second representations. When the operating point lies between the first and second representations, an interpolation may be conducted between the first and second representations to determine a magnitude of the voltage command.
    Type: Application
    Filed: April 4, 2017
    Publication date: October 4, 2018
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: XIN JING, BRIAN A. WELCHKO, CONSTANTIN C. STANCU
  • Patent number: 10056792
    Abstract: An interior permanent magnet electric machine is described, and includes a stator including a plurality of electrical windings and a rotor disposed in a cylindrically-shaped void formed within the stator. The rotor includes a plurality of steel laminations assembled onto a shaft, wherein the shaft defines a longitudinal axis. Each of the steel laminations includes a plurality of poles and each of the poles includes a plurality of slots disposed near an outer periphery. The slots of the steel laminations are longitudinally aligned. A plurality of permanent magnets are disposed in a first subset of the slots, and plurality of packets assembled from anisotropic material are disposed in a second subset of the slots.
    Type: Grant
    Filed: May 4, 2016
    Date of Patent: August 21, 2018
    Assignee: GM Global Technology Operations LLC
    Inventors: Khwaja M. Rahman, Constantin C. Stancu, Peter J. Savagian, Nitinkumar R. Patel, Robert T. Dawsey
  • Publication number: 20180166410
    Abstract: A power module assembly has a first substrate including a first layer, second layer and a third layer. The first layer is configured to carry a switch current flowing in a first direction. A second substrate is operatively connected to the first substrate and includes a fourth layer, fifth layer and a sixth layer. A conductive joining layer connects the third layer of the first substrate and the fourth layer of the second substrate. The conductive joining layer may be a first sintered layer. The third layer of the first substrate, the first sintered layer and the fourth layer of the second substrate are configured to function together as a unitary conducting layer carrying the switch current in a second direction substantially opposite to the first direction. The net inductance is reduced by a cancellation effect of the switch current going in opposite directions.
    Type: Application
    Filed: December 14, 2016
    Publication date: June 14, 2018
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Terence G. Ward, Constantin C. Stancu, Marko Jaksic
  • Publication number: 20180076153
    Abstract: A power module assembly has a plurality of electrically conducting layers, including a first layer and a third layer. One or more electrically insulating layers are operatively connected to each of the plurality of electrically conducting layers. The electrically insulating layers include a second layer positioned between and configured to electrically isolate the first and the third layers. The first layer is configured to carry a first current flowing in a first direction. The third layer is configured to carry a second current flowing in a second direction opposite to the first direction, thereby reducing an inductance of the assembly. The electrically insulating layers may include a fourth layer positioned between and configured to electrically isolate the third layer and a fifth layer. The assembly results in a combined substrate and heat sink structure. The assembly eliminates the requirements for connections between separate substrate and heat sink structures.
    Type: Application
    Filed: September 9, 2016
    Publication date: March 15, 2018
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Terence G. Ward, Constantin C. Stancu, Marko Jaksic, Brooks S. Mann
  • Patent number: 9917065
    Abstract: A power module assembly has a plurality of electrically conducting layers, including a first layer and a third layer. One or more electrically insulating layers are operatively connected to each of the plurality of electrically conducting layers. The electrically insulating layers include a second layer positioned between and configured to electrically isolate the first and the third layers. The first layer is configured to carry a first current flowing in a first direction. The third layer is configured to carry a second current flowing in a second direction opposite to the first direction, thereby reducing an inductance of the assembly. The electrically insulating layers may include a fourth layer positioned between and configured to electrically isolate the third layer and a fifth layer. The assembly results in a combined substrate and heat sink structure. The assembly eliminates the requirements for connections between separate substrate and heat sink structures.
    Type: Grant
    Filed: September 9, 2016
    Date of Patent: March 13, 2018
    Assignee: GM Global Technology Operations LLC
    Inventors: Terence G. Ward, Constantin C. Stancu, Marko Jaksic, Brooks S. Mann
  • Patent number: 9853589
    Abstract: An electric power system including a front-end converter that is supplied electric power from a high-voltage DC power source, and an associated motor control system is described. A control method includes monitoring the electric machine and determining a reference current based upon the electric power supplied from the high-voltage DC power source. A motor current is determined based upon the monitoring of the electric machine, and a feed-forward current is determined based upon the motor current and the monitoring of the electric machine. A first duty cycle is determined based upon the reference current, the motor current and the feed-forward current, and a feed-forward duty cycle is determined based upon the monitoring of the electric machine. A second duty cycle is determined based upon the feed-forward duty cycle and the first duty cycle, and the front-end converter is controlled based upon the second duty cycle.
    Type: Grant
    Filed: March 3, 2016
    Date of Patent: December 26, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Xin Jing, Constantin C. Stancu, Brian A. Welchko
  • Patent number: 9796277
    Abstract: A number of variations may include a product comprising: an extended range battery system for an electric bicycle comprising a first battery system and a second battery system, and wherein direct current biasing is utilized between the first battery system and the second battery system to extend the range of the extended range battery system.
    Type: Grant
    Filed: February 27, 2015
    Date of Patent: October 24, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Steven L. Hayslett, Constantin C. Stancu, Jorge G. Cintron-Rivera
  • Publication number: 20170302215
    Abstract: An electric power system for supplying power to a permanent magnet electric machine includes a high-voltage DC power source that is disposed to supply electric power to a front-end converter connected via a high-voltage DC bus to an electric inverter that is connected to the electric machine. A method for operating a control system includes monitoring the electric machine. Upon detecting a fault associated with the electric machine, a controller commands operation of the front-end converter to generate a voltage level on the high-voltage DC bus that is a maximum setpoint voltage level and monitors back-emf voltage level from the electric machine. The inverter is controlled to a three-phase open state when the back-emf voltage level is less than the maximum setpoint voltage level. The inverter is controlled to a three-phase short state when the back-emf voltage level is greater than the maximum setpoint voltage level.
    Type: Application
    Filed: April 15, 2016
    Publication date: October 19, 2017
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Xin Jing, Brian A. Welchko, Constantin C. Stancu
  • Patent number: 9780665
    Abstract: Methods and systems are provided for control operation of a boost converter. The boost converter includes an input, an output, and a plurality of paths electrically connecting the input to the output. The boost converter also includes a plurality of switches disposed along the paths to control current flow between the input and the output. The system includes a controller. The controller receives a desired current to be supplied at the output. The controller determines which of the paths to utilize based at least in part on the desired current. The controller controls the switches based at least in part on the determination of which of the paths to utilize.
    Type: Grant
    Filed: March 15, 2012
    Date of Patent: October 3, 2017
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Lihua Li, Seok-Joo Jang, Ray M Ransom, Constantin C. Stancu
  • Patent number: 9774288
    Abstract: An electric machine assembly includes an electric machine, an inverter configured to provide pulse-width modulation characterized by a switching frequency and a controller. The controller has a processor and tangible, non-transitory memory on which is recorded instructions for executing a method of controlling the switching frequency to minimize a beat frequency phenomenon. Execution of the instructions by the processor causes the controller to obtain a first function (G1) and a second function (G2) based at least partially on the original pulse ratio (PR0). The original pulse ratio (PR0) is a ratio of the switching frequency and a predefined fundamental frequency. If each of a plurality of conditions are met, a new pulse ratio (PRN) is determined based at least partially on the original pulse ratio (PR0), the first function (G1) and the second function (G2).
    Type: Grant
    Filed: August 2, 2016
    Date of Patent: September 26, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Xin Jing, Brian A. Welchko, Constantin C. Stancu
  • Publication number: 20170257049
    Abstract: An electric power system including a front-end converter that is supplied electric power from a high-voltage DC power source, and an associated motor control system is described. A control method includes monitoring the electric machine and determining a reference current based upon the electric power supplied from the high-voltage DC power source. A motor current is determined based upon the monitoring of the electric machine, and a feed-forward current is determined based upon the motor current and the monitoring of the electric machine. A first duty cycle is determined based upon the reference current, the motor current and the feed-forward current, and a feed-forward duty cycle is determined based upon the monitoring of the electric machine. A second duty cycle is determined based upon the feed-forward duty cycle and the first duty cycle, and the front-end converter is controlled based upon the second duty cycle.
    Type: Application
    Filed: March 3, 2016
    Publication date: September 7, 2017
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Xin Jing, Constantin C. Stancu, Brian A. Welchko
  • Publication number: 20170229934
    Abstract: An interior permanent magnet electric machine is described, and includes a stator including a plurality of electrical windings and a rotor disposed in a cylindrically-shaped void formed within the stator. The rotor includes a plurality of steel laminations assembled onto a shaft, wherein the shaft defines a longitudinal axis. Each of the steel laminations includes a plurality of poles and each of the poles includes a plurality of slots disposed near an outer periphery. The slots of the steel laminations are longitudinally aligned. A plurality of permanent magnets are disposed in a first subset of the slots, and plurality of packets assembled from anisotropic material are disposed in a second subset of the slots.
    Type: Application
    Filed: May 4, 2016
    Publication date: August 10, 2017
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Khwaja M. Rahman, Constantin C. Stancu, Peter J. Savagian, Nitinkumar R. Patel, Robert T. Dawsey
  • Publication number: 20170229928
    Abstract: A synchronous reluctance electric machine is described, and includes a stator including a plurality of electrical windings and a rotor disposed in a cylindrically-shaped void formed within the stator. The rotor includes a plurality of steel laminations assembled onto a shaft, wherein the shaft defines a longitudinal axis. Each of the steel laminations includes a plurality of poles and each of the poles includes a plurality of slots disposed near an outer periphery. The slots of the steel laminations are longitudinally aligned. A plurality of packets assembled from anisotropic material are disposed in the slots.
    Type: Application
    Filed: May 4, 2016
    Publication date: August 10, 2017
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Constantin C. Stancu, Peter J. Savagian, Khwaja M. Rahman, Nitinkumar R. Patel, Robert T. Dawsey
  • Publication number: 20160250937
    Abstract: A number of variations may include a product comprising: an extended range battery system for an electric bicycle comprising a first battery system and a second battery system, and wherein direct current biasing is utilized between the first battery system and the second battery system to extend the range of the extended range battery system.
    Type: Application
    Filed: February 27, 2015
    Publication date: September 1, 2016
    Inventors: Steven L. Hayslett, Constantin C. Stancu, Jorge G. Cintron-Rivera
  • Publication number: 20160056676
    Abstract: A partially segmented rotor assembly for an electric motor and a method for the same is provided. The partially segmented rotor assembly includes a first rotor segment and a plurality of second rotor segments. The first rotor segment has a plurality of first poles wound with a wire and defines a first circumferential gap between the wire of each adjacent pair of the first poles. Each second rotor segment has a second pole wound with the wire and is rigidly attached to the first rotor segment in a respective one of the first circumferential gaps to form a plurality of second circumferential gaps between the wire of each first pole and the wire of the adjacent second poles. The first and second rotor segments are configured to cooperate with one another to minimize the second circumferential gaps.
    Type: Application
    Filed: August 25, 2014
    Publication date: February 25, 2016
    Inventors: Terence G. Ward, Constantin C. Stancu, Khwaja M. Rahman, Srihari Gangaraj, Brooks S. Mann
  • Patent number: 9064630
    Abstract: An integrated rotary transformer and resolver and a motor including an integrated rotary transformer and resolver is provided. The integrated rotary transformer and resolver may include, but is not limited to, a stator having an outer surface and a plurality of slots disposed along the outer surface, a plurality of sensing coils, the plurality of sensing coils disposed in at least some of the plurality of slots, a rotor having a surface varying from a first predetermined thickness to a second predetermined thickness, and a controller electrically coupled to the plurality of sensing coils and configured to determine a position of the rotor based upon a voltage induced in each of the coils due to a relative thickness of the rotor opposed to the respective sensing coil.
    Type: Grant
    Filed: October 17, 2011
    Date of Patent: June 23, 2015
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Seok-Joo Jang, Peter J. Savagian, Constantin C. Stancu