Patents by Inventor Lei Hao

Lei Hao 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: 20170334422
    Abstract: A vehicle propulsion system includes an engine and a first electric machine each configured to selectively provide torque to propel the vehicle. The propulsion system also includes a second electric machine coupled to the engine and configured to start the engine from an inactive state. A high-voltage battery powers both of the first electric machine and the second electric machine over a high-voltage bus. The vehicle further includes a controller programmed to issue a command to start the engine using the second electric machine in response to a threshold acceleration demand following a period of reduced acceleration demand.
    Type: Application
    Filed: May 19, 2016
    Publication date: November 23, 2017
    Inventors: Chandra S. Namuduri, Lei Hao, Suresh Gopalakrishnan, Thomas W. Nehl
  • Publication number: 20170335816
    Abstract: A vehicle propulsion system includes an engine and a first electric machine each configured to selectively provide torque to propel the vehicle. The propulsion system also includes a second electric machine coupled to the engine and configured to start the engine from an inactive state. A controller is programmed to execute a first control algorithm while output speed of the second electric machine is less than a first speed threshold. The controller is also programmed to execute a second control algorithm while output speed of the second electric machine is greater than the first speed threshold and less than a second speed threshold.
    Type: Application
    Filed: May 19, 2016
    Publication date: November 23, 2017
    Inventors: Lei Hao, Chandra S. Namuduri, Thomas W. Nehl
  • Publication number: 20170334297
    Abstract: An interior permanent magnet electric machine includes a stator having a plurality of teeth disposed around a circumference oriented radially towards a center defining slots interposed between each of the teeth, and a conductive winding wrapped around each of the teeth of the stator to receive an electrical current. The electric machine also includes a rotor which is rotatable relative to the stator. The rotor defines a plurality of openings to receive permanent magnets near an outer portion of the rotor and a number of spokes interposed between mass reduction cutouts located closer to the center relative to the permanent magnets. Each of the permanent magnets defines a magnetic pole and each of the spokes is circumferentially aligned with one of the magnetic poles.
    Type: Application
    Filed: May 19, 2016
    Publication date: November 23, 2017
    Inventors: Lei Hao, Chandra S. Namuduri, Murali Pandi, Thomas W. Nehl
  • Publication number: 20170310263
    Abstract: An electric drive system for a three-phase PM electric machine. The drive system includes a split stator winding for each phase of the machine including a first winding section and a second winding section, and an inverter circuit including a pair of inverter switches for each phase, where the pair of inverter switches for each phase is electrically coupled to the first and second winding sections for that phase in the stator. The drive system also includes a switching system including a switch circuit, where the switch circuit includes a plurality of switch assemblies for switching between a full winding control mode and a half winding control mode, where each switch assembly includes a first AC switching device and a second AC switching device, and where each switch assembly is electrically coupled to the pair of inverter switches and the first and second winding sections for a particular phase.
    Type: Application
    Filed: April 22, 2016
    Publication date: October 26, 2017
    Inventors: CHANDRA S. NAMUDURI, LEI HAO
  • Patent number: 9780606
    Abstract: The disclosure may generally relate to a motor which may include a rotor core which may include a first rotor lamination portion and a second rotor lamination portion. At least one magnet may be operably coupled to the first rotor lamination. The first rotor lamination may be in contact with the at least one magnet and the second rotor lamination may not be in contact with the at least one magnet. Additionally, the first rotor lamination and the second rotor lamination may be comprised of different materials.
    Type: Grant
    Filed: February 18, 2015
    Date of Patent: October 3, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Murali Pandi, Lei Hao
  • Patent number: 9732736
    Abstract: A system for controlling an active material actuator includes an active material actuator configured to actuate when energized, a power supply configured to supply electrical power, and a control circuitry including a plurality of circuits and configured to selectively establish an electrical connection between the active material actuator and the power supply upon receipt of an activation signal. The control circuitry is configured to de-energize at least one of the circuits when no activation signal is received by the control circuitry in order to minimize parasitic current drawn from the power supply.
    Type: Grant
    Filed: March 27, 2014
    Date of Patent: August 15, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Chandra S. Namuduri, Lei Hao, Paul W. Alexander, Xiujie Gao
  • Patent number: 9735634
    Abstract: A rotor for a permanent magnet synchronous machine that includes a rotor core structure. A first set of permanent magnets forms poles within the rotor core structure. Each pole includes a pair of permanent magnets from the first set of permanent magnets. A first set of apertures is formed in a first radial layer of the rotor core structure. Each pole includes a pair of apertures from the first set of apertures. The first set of permanent magnets is inserted within the first set of apertures. Each pair of permanent magnets within a pole cooperatively generates a magnetic field in a same direction within the pole. The magnetic field generated by a respective pair of magnets in a respective pole is opposite to a magnetic field generated by a pair of permanent magnets in an adjacent pole.
    Type: Grant
    Filed: July 22, 2014
    Date of Patent: August 15, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Lei Hao, Thomas W. Nehl, Chandra S. Namuduri, Michael G. Reynolds, Alexandru Rajala
  • Patent number: 9692266
    Abstract: A rotor of a permanent magnet synchronous machine includes a rotor core structure. A first set of apertures are formed in a first radial layer of the rotor core structure having a first set of permanent magnets disposed therein forming respective poles. A second set of apertures formed in a second radial layer of the rotor core structure of each pole. A third set of apertures is formed in a third radial layer of the rotor core structure. A second set of permanent magnets is inserted within the third set of apertures. A plurality of bridges each extends across a respective side of each of the third set of apertures in the third radial layer. The plurality of bridges provides structural support of the rotor core structure when operating. The plurality of bridges are integrally formed as single-piece laminations.
    Type: Grant
    Filed: July 22, 2014
    Date of Patent: June 27, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Thomas W. Nehl, Lei Hao, Rajeev Vyas, Chandra S. Namuduri, Michael G. Reynolds
  • Publication number: 20170102425
    Abstract: A method and system are disclosed for detecting turn-to-turn and phase-to-phase winding short circuits in an electric motor. The motor is tested at a standstill condition by injecting a current signal into the virtual d-axis of the motor while controlling q-axis current to zero. Steady state feedback current from the motor is measured, and current harmonics are calculated using FFT or peak-to-peak techniques. It is determined that a short circuit is present in the winding if feedback current harmonics higher than a nominal level are detected, where the increased feedback current is an indication that winding inductance has decreased due to a short circuit. Testing at standstill using a small current advantageously prevents the possibility of damaging the motor and avoids inductance variation due to changing rotor position.
    Type: Application
    Filed: October 13, 2015
    Publication date: April 13, 2017
    Inventors: Lei HAO, Cristian A. LOPEZ-MARTINEZ, Chad A. FREITAS
  • Patent number: 9621099
    Abstract: A method for controlling switching between a full winding control mode and a half winding control mode for a multi-phase electric machine. The machine includes a stator and a rotor, split stator windings for each phase of the machine, where each stator winding includes a first winding section and a second winding section, an inverter circuit including a pair of inverter switches for each phase of the machine, where the pair of inverter switches for each phase is electrically coupled to the first and second winding sections for that phase, and a plurality of switch assemblies for switching between the full winding mode and the half winding mode, where each switch assembly is electrically coupled to the pair of inverter switches and the first and second winding sections for a particular phase, and where each switch assembly includes a first AC switching device and a second AC switching device.
    Type: Grant
    Filed: April 22, 2016
    Date of Patent: April 11, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Chandra S. Namuduri, Lei Hao
  • Patent number: 9597979
    Abstract: A method of controlling a powertrain of a hybrid vehicle includes comparing an operating efficiency of a motor-generator-inverter to an upper MGI efficiency threshold when a boost operating mode is selected. When the operating efficiency of the motor-generator-inverter is equal to or greater than the upper MGI efficiency threshold, the motor-generator-inverter is controlled to operate in the boost operating mode. The operating efficiency of the motor-generator-inverter is compared to a lower MGI efficiency threshold when a regenerative operating mode is selected. When the operating efficiency of the motor-generator-inverter is equal to or greater than the lower MGI efficiency threshold, the motor-generator-inverter is controlled to operate in the regenerative operating mode.
    Type: Grant
    Filed: April 13, 2016
    Date of Patent: March 21, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Lei Hao, Venkata Prasad Atluri, Suresh Gopalakrishnan, Chandra S. Namuduri, Avoki M. Omekanda
  • Publication number: 20170077848
    Abstract: A transmission assembly has an integrated torque machine including a torque machine stator and a torque machine rotor. The torque machine rotor includes at least one set of rotor magnets. An integrated rotational position sensor is configured to monitor rotational position of the torque machine rotor in relation to the torque machine stator. The integrated rotational position sensor includes a sensor rotor element and a sensor stator element. The sensor rotor element includes at least one set of sensor rotor magnets. The sensor rotor element is positioned such that the at least one set of sensor rotor magnets are aligned with respect to a rotor pole of the at least one set of rotor magnets of the torque machine rotor. The sensor stator element is positioned such that the sensor stator element is aligned with a magnetic axis of the torque machine stator.
    Type: Application
    Filed: September 15, 2015
    Publication date: March 16, 2017
    Inventors: SURESH GOPALAKRISHNAN, CHANDRA S. NAMUDURI, LEI HAO, ALEXANDRU RAJALA
  • Publication number: 20170057373
    Abstract: An electric machine is provided for a dual voltage power system having a first energy storage system (HV-ESS) with a first nominal voltage and second energy storage system (LV-ESS with a second nominal voltage). The electric machine includes a rotor assembly having a rotor core configured to support permanent magnets spaced around the rotor core to define a number of rotor poles. The rotor core has multiple rotor slots arranged as at least one barrier layer at each of the rotor poles. Permanent magnets are disposed in the at least one barrier layer. A stator assembly surrounds the rotor assembly. The electric machine is configured to be operatively connected with the HV-ESS. The electric machines has at least one of a predetermined efficiency at rated power, a predetermined power density, a predetermined torque density, a predetermined peak power range, or a predetermined maximum speed of the electric machine.
    Type: Application
    Filed: June 28, 2016
    Publication date: March 2, 2017
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Lei Hao, Chandra S. Namuduri, Thomas W. Nehl
  • Publication number: 20170063187
    Abstract: An electric machine is provided that has a rotor assembly having a rotor core configured to support permanent magnets spaced around the rotor core to define a number of rotor poles. The rotor core has multiple rotor slots arranged as multiple barrier layers at each of the rotor poles. The multiple barrier layers are positioned adjacent one another between an inner periphery of the rotor core and an outer periphery of the rotor core and include a first barrier layer nearest the inner periphery. Permanent magnets are disposed in at least the first barrier layer. A stator assembly surrounds the rotor assembly. The electric machine is configured to function as a motor in a motoring mode and as a generator in a generating mode. The electric machine is configured with predetermined operating parameters selected for optimizing operation in the motoring mode and/or the generating mode.
    Type: Application
    Filed: June 28, 2016
    Publication date: March 2, 2017
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Lei Hao, Chandra S. Namuduri, Thomas W. Nehl
  • Patent number: 9479017
    Abstract: A rotor for a permanent magnet synchronous machine. A first layer of cavities formed circumferentially within the rotor core structure. Pairs of the cavities in the first layer form V-shaped configurations and are spaced circumferentially about the rotor core structure in the first layer. A second layer of cavities is formed circumferentially within the rotor core structure. Pairs of the cavities in the second layer form V-shaped configurations and are spaced circumferentially about the rotor core structure in the second layer. A first set of permanent magnets is inserted within each cavity in the first layer and a second set of permanent magnets inserted within each cavity in the second layer. Each respective V-shaped configuration of the second layer having permanent magnets disposed therein extend greater than half a radial distance from the outer cylindrical wall to the inner cylindrical wall.
    Type: Grant
    Filed: July 22, 2014
    Date of Patent: October 25, 2016
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Lei Hao, Thomas W. Nehl
  • Publication number: 20160241089
    Abstract: The disclosure may generally relate to a motor which may include a rotor core which may include a first rotor lamination portion and a second rotor lamination portion. At least one magnet may be operably coupled to the first rotor lamination. The first rotor lamination may be in contact with the at least one magnet and the second rotor lamination may not be in contact with the at least one magnet. Additionally, the first rotor lamination and the second rotor lamination may be comprised of different materials.
    Type: Application
    Filed: February 18, 2015
    Publication date: August 18, 2016
    Inventors: MURALI PANDI, LEI HAO
  • Patent number: 9387766
    Abstract: A vehicle includes a transmission, energy storage system (ESS), power inverter module (PIM), and controller. The PIM includes a boost converter having a bypass switch and a first plurality of switches, and also a power inverter having a second plurality of switches. The controller is programmed to execute a method that enables a DC boost converter of the PIM by opening the bypass switch when a speed and a torque of the electric machine are within a predetermined boost range. The controller bypasses the boost converter by transmitting a second switching signal closing the bypass switch when the speed and torque are not within the predetermined boost range. A voltage input to the power inverter is equal to the DC battery voltage whenever the boost converter is bypassed and exceeds the DC battery voltage whenever the boost converter is enabled.
    Type: Grant
    Filed: September 11, 2014
    Date of Patent: July 12, 2016
    Assignee: GM Global Technology Operations LLC
    Inventors: Lei Hao, Chandra S. Namuduri, Thomas Wolfgang Nehl, Suresh Gopalakrishnan
  • Patent number: 9346345
    Abstract: A vent assembly is disposed within an interior space of a vehicle for opening and closing fluid communication between the interior space and an exterior of the vehicle. The vent assembly includes a housing defining a plurality of openings and a plurality of vanes disposed in the openings. An actuator mechanism moves the vanes between an open position and a closed position, and includes a shaped memory alloy (SMA) member for actuating the vanes between the open and closed positions. The SMA member is activated when a hatch of the vehicle is opened to move the vanes into the open position and thereby open fluid communication between the interior space and the exterior to alleviate excessive air pressure buildup during closure of the hatch.
    Type: Grant
    Filed: July 10, 2014
    Date of Patent: May 24, 2016
    Assignee: GM Global Technology Operations LLC
    Inventors: Paul W. Alexander, Xiujie Gao, Alan L. Browne, Mark A. Voss, Derek L. Patterson, Lei Hao, Chandra S. Namuduri, James Holbrook Brown, Aragorn Zolno, John N. Owens, Alexander Millerman, Kevin B. Rober, Suresh Gopalakrishnan, Sanjeev M. Naik
  • Publication number: 20160075241
    Abstract: A vehicle includes a transmission, energy storage system (ESS), power inverter module (PIM), and controller. The PIM includes a boost converter having a bypass switch and a first plurality of switches, and also a power inverter having a second plurality of switches. The controller is programmed to execute a method that enables a DC boost converter of the PIM by opening the bypass switch when a speed and a torque of the electric machine are within a predetermined boost range. The controller bypasses the boost converter by transmitting a second switching signal closing the bypass switch when the speed and torque are not within the predetermined boost range. A voltage input to the power inverter is equal to the DC battery voltage whenever the boost converter is bypassed and exceeds the DC battery voltage whenever the boost converter is enabled.
    Type: Application
    Filed: September 11, 2014
    Publication date: March 17, 2016
    Inventors: Lei Hao, Chandra S. Namuduri, Thomas Wolfgang Nehl, Suresh Gopalakrishnan
  • Publication number: 20160028280
    Abstract: A rotor of a permanent magnet synchronous machine includes a rotor core structure. A first set of apertures are formed in a first radial layer of the rotor core structure having a first set of permanent magnets disposed therein forming respective poles. A second set of apertures formed in a second radial layer of the rotor core structure of each pole. A third set of apertures is formed in a third radial layer of the rotor core structure. A second set of permanent magnets is inserted within the third set of apertures. A plurality of bridges each extends across a respective side of each of the third set of apertures in the third radial layer. The plurality of bridges provides structural support of the rotor core structure when operating. The plurality of bridges are integrally formed as single-piece laminations.
    Type: Application
    Filed: July 22, 2014
    Publication date: January 28, 2016
    Inventors: THOMAS W. NEHL, LEI HAO, RAJEEV VYAS, CHANDRA S. NAMUDURI, MICHAEL G. REYNOLDS