Patents by Inventor Suresh Gopalakrishnan

Suresh Gopalakrishnan 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: 11133680
    Abstract: System and method of dynamically balancing a rechargeable energy storage assembly having two or more respective units, a respective switch for each of the respective units and at least one sensor. The system includes a controller configured to control operation of the respective switch. The respective switch is configured to enable a respective circuit connection to the respective units when in an ON state and disable the respective circuit connection when in an OFF state. The respective units are characterized by a respective state of charge obtained based in part on the at least one sensor. A controller is configured to selectively employ at least one of a plurality of charging modes to charge one or more of the respective units, through operation of the respective switch. The plurality of charging modes includes a rest charging mode, a rapid initial charging mode and a rapid final charging mode.
    Type: Grant
    Filed: January 8, 2019
    Date of Patent: September 28, 2021
    Assignee: GM Global Technology Operations LLC
    Inventors: Yue-Yun Wang, Lei Hao, Suresh Gopalakrishnan
  • Publication number: 20210242691
    Abstract: A system for use with a direct current fast-charging (DCFC) station includes a controller and battery system. The battery system includes first and second battery packs, and first, second, and third switches. The switches have ON/OFF conductive states commanded by the controller to connect the battery packs in a parallel-connected (P-connected) or series-connected (S-connected) configuration. An electric powertrain with one or more electric machines is powered via the battery system. First and second charge ports of the system are connectable to the station via a corresponding charging cable. The first charge port receives a low or high charging voltage from the station. The second charge port receives a low charging voltage. When the station can supply the high charging voltage to the first charge port, the controller establishes the S-connected configuration via the switches, and thereafter charges the battery system solely via the first charge port.
    Type: Application
    Filed: February 3, 2020
    Publication date: August 5, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Lei Hao, Yue-Yun Wang, Suresh Gopalakrishnan, Chandra S. Namuduri, Rashmi Prasad, Madhusudan Raghavan
  • Publication number: 20210239449
    Abstract: An electric powertrain includes a sensor-controller interface, an inverter-controller electrically connected to the battery pack, and an electric machine connected to the inverter-controller and having a rotor with an angular position. The rotor powers a driven load at a torque and/or speed level controlled by the inverter-controller in response to position signals indicative of the angular position. A rotary position sensor is operatively connected to the rotor to generate and output the position signals. The sensor derives the position signals from unmodulated sine and cosine signals, and communicates the position signals and a binary sensor state of health (SOH) to the inverter-controller over the interface. The inverter-controller also decodes the position signals and the binary sensor SOH to generate decoded control data, and controls the torque and/or speed level using the decoded control data.
    Type: Application
    Filed: January 30, 2020
    Publication date: August 5, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Suresh Gopalakrishnan, Shuqing Zeng, Chandra S. Namuduri
  • Publication number: 20210234447
    Abstract: An electric machine includes a machine rotor circumscribed by a machine stator, and having a rotor shaft, rotor stack, and end cap which rotate about an axis. The end cap includes lobes equal in number to a number of pole pairs of the machine rotor. A position sensor assembly has a predetermined alignment with the machine rotor and stator. The sensor assembly includes a sensor rotor formed by the lobes and a sensor stator having a printed circuit board with conductive sine and cosine traces. Machine rotor rotation causes the sensor assembly to output an unmodulated sine and cosine signals to a controller, which then calculates a calibrated reference angle. A magnetic axis of an electrical phase of the machine is aligned with and bisects a peak of the sine trace. A direct axis of the machine rotor aligns with an edge of a lobe.
    Type: Application
    Filed: January 28, 2020
    Publication date: July 29, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Suresh Gopalakrishnan, Chandra S. Namuduri, Alexandru Rajala, Thomas W. Nehl, Xiaohui Du, Edward L. Kaiser
  • Publication number: 20210207666
    Abstract: A controller executes a method to manage an engine connect/disconnect decision in a powertrain having an engine, transmission, electric machine, and a battery pack and power inverter module (“TPIM”). In response to vehicle ground speed being less than a calibrated maximum electric vehicle accelerator pedal signal (“EVAPS”) level, the controller calculates a delta APS (“?PS”) value by subtracting a scaled APS value from the actual APS level. The scaled APS value is a scaled variant of a maximum EVAPS value selected from a maximum EVSAPS table, the latter populated based on inverter temperature, state of charge of the battery pack, and ground speed. When the ?APS value exceeds a threshold, the controller connects the engine to the transmission via an engine disconnect clutch. The engine is disconnected based on acceleration of the vehicle and the above-noted factors.
    Type: Application
    Filed: January 6, 2020
    Publication date: July 8, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Norman K. Bucknor, Chunhao J. Lee, Neeraj S. Shidore, Dongxu Li, Suresh Gopalakrishnan
  • Publication number: 20210129686
    Abstract: An electric propulsion system includes a battery pack and a DC-DC converter. The converter has a bypass switch and semiconductor switches. A traction power inverter module (“TPIM”) rectifies a DC bus voltage on the voltage bus to produce an AC bus voltage. An electric machine is connected to the TPIM and energized via the AC bus voltage. A controller calculates required output power from the converter based on a requested operating mode, and speed and torque of the electric machine. When the output power exceeds a threshold, the bypass switch closes to bypass the converter. When the output power is less than the threshold, the controller uses a minimum loss voltage from a loss map as a target control voltage of the converter to optimize efficiency of the electric propulsion system.
    Type: Application
    Filed: November 6, 2019
    Publication date: May 6, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Lei Hao, Chandra S. Namuduri, Suresh Gopalakrishnan, Chengwu Duan, Norman K. Bucknor
  • Publication number: 20210107348
    Abstract: A vehicle powertrain includes a first power-source configured to generate a first power-source torque and a multiple speed-ratio transmission configured to transmit the first power-source torque to power the vehicle. The powertrain also includes a fluid coupling having a fluid pump shaft operatively connected to the first power-source and a turbine shaft operatively connected to the multi-speed transmission. The fluid coupling is configured to multiply the first power-source torque, and transfer the multiplied first power-source torque to the multiple speed-ratio transmission. The powertrain additionally includes a second power-source configured to generate a second power-source torque and a first torque transfer system configured to connect the second power-source to the first power-source. The powertrain further includes a second torque transfer system configured to connect the second power-source to the multi-speed transmission. A motor vehicle having such a powertrain is also envisioned.
    Type: Application
    Filed: October 9, 2019
    Publication date: April 15, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Neeraj S. Shidore, Derek F. Lahr, Lei Hao, Madhusudan Raghavan, Suresh Gopalakrishnan
  • Publication number: 20210061117
    Abstract: An automotive vehicle includes a vehicle-based charging unit including a receiving unit configured to receive power from a ground-based charging unit, the receiving unit including a multi-coil receiver, a first actuator operably coupled to the vehicle-based charging unit and configured to adjust a first position of the vehicle-based charging unit relative to the ground-based charging unit, and a controller configured to selectively actuate the first actuator.
    Type: Application
    Filed: August 28, 2019
    Publication date: March 4, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Kausalya Singuru, Suresh Gopalakrishnan, Nikolai K. Moshchuk, David Andrés Pérez Chaparro
  • Patent number: 10915423
    Abstract: A system for and method of analyzing user tools to detect and remediate those tools posing a high risk to an organization. The system and method involve calculating user tool complexity to predict potential tool failures and displaying the potential failures to a user for further analysis. Remediation tools are provided to permit the user to correct or minimize the potential failures. The user can identify high risk tools and mark potential risks in those tools as mitigated, pending mitigation, or no mitigation action required.
    Type: Grant
    Filed: January 10, 2019
    Date of Patent: February 9, 2021
    Assignee: JPMORGAN CHASE BANK, N.A.
    Inventors: Julie Cowan, Disha Dua, Liang Sun, Felix Shamis, Suresh Gopalakrishnan, Meshraj Khatiwada
  • Patent number: 10900458
    Abstract: A method of stopping an engine crankshaft includes selecting a target angular position at which the engine crankshaft is to be stopped and detecting an actual angular position of the engine crankshaft and a rotational speed of the engine crankshaft. A stopping torque in calculated based on the actual angular position of the engine crankshaft and the rotational speed of the engine crankshaft. The stopping torque is applied to the engine crankshaft via a motor/generator operably connected to the engine crankshaft. The engine crankshaft is stopped at the target angular position via the application of the stopping torque.
    Type: Grant
    Filed: May 8, 2019
    Date of Patent: January 26, 2021
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Suresh Gopalakrishnan, Paul S. Lombardo, David W. Walters, Chunhao J. Lee, Chandra S. Namuduri, Neeraj S. Shidore, Thomas W. Nehl
  • Publication number: 20200391724
    Abstract: A powertrain system configured to transfer torque to a driveline is described, and includes an internal combustion engine, a torque converter, a transmission, an electric machine, and a controller. The engine is configured to operate in one of an all-cylinder mode and a dynamic deactivation mode to generate an engine torque. The electric machine is configured to generate a motor torque. The motor torque and the engine torque combine to generate an output torque that is transferable to the driveline and is responsive to an output torque request. The controller is in communication with the engine, the torque converter, the transmission, and the electric machine. The controller includes an instruction set that is executable to operate the engine in the dynamic deactivation mode to generate engine torque, and operate the electric machine to generate motor torque to supplement the engine torque to generate the output torque.
    Type: Application
    Filed: June 12, 2019
    Publication date: December 17, 2020
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Neeraj S. Shidore, Norman K. Bucknor, Dongxu Li, Mark Tadrous, Derek F. Lahr, Suresh Gopalakrishnan, Venkatesh Gopalakrishnan
  • Patent number: 10854933
    Abstract: Presented are battery pack voltage-switching (“V-switch”) systems, methods for making/operating such systems, and multi-pack, electric-drive motor vehicles with battery pack V-switch capabilities. A method for controlling operation of a vehicle includes a vehicle controller receiving a voltage switch signal to change a voltage output of the vehicle's battery system. The vehicle controller determines if a speed of a traction motor is less than a calibrated base speed; if so, the controller transmits a pack isolation signal to a power inverter to electrically disconnect the traction battery packs from the traction motor. The vehicle controller determines if a bus current of a DC bus is less than a calibrated bus current threshold; if so, the controller transmits an open signal to open one or more pack contactor switches and a close signal to close one or more pack contactor switches thereby causing the vehicle battery system to output the second voltage.
    Type: Grant
    Filed: January 18, 2019
    Date of Patent: December 1, 2020
    Assignee: GM Global Technology Operations LLC
    Inventors: Lei Hao, Yue-Yun Wang, Chandra S. Namuduri, Suresh Gopalakrishnan, Thomas W. Nehl, Dongxu Li
  • Publication number: 20200355152
    Abstract: A method of stopping an engine crankshaft includes selecting a target angular position at which the engine crankshaft is to be stopped and detecting an actual angular position of the engine crankshaft and a rotational speed of the engine crankshaft. A stopping torque in calculated based on the actual angular position of the engine crankshaft and the rotational speed of the engine crankshaft. The stopping torque is applied to the engine crankshaft via a motor/generator operably connected to the engine crankshaft. The engine crankshaft is stopped at the target angular position via the application of the stopping torque.
    Type: Application
    Filed: May 8, 2019
    Publication date: November 12, 2020
    Inventors: Suresh Gopalakrishnan, Paul S. Lombardo, David W. Walters, Chunhao J. Lee, Chandra S. Namuduri, Neeraj S. Shidore, Thomas W. Nehl
  • Patent number: 10815954
    Abstract: An engine starter system includes a starter including a multi-phase brushless electric motor and an electronic commutator assembly. A controller includes an instruction set that is executable in response to a command to execute an engine starting event. Operation includes determining a desired starting profile, controlling the starter to engage a rotatable member of the engine, and monitoring the rotational speed of the electric motor via a rotor position sensing circuit. The starter inverter is dynamically controlled to control the electric motor to spin the rotatable member of the internal combustion engine responsive to the desired starting profile, including dynamically controlling the starter inverter to control the electric motor to control the spin of the engine responsive to the desired starting profile to prevent occurrence of an engine speed flare event during the engine starting event.
    Type: Grant
    Filed: May 1, 2018
    Date of Patent: October 27, 2020
    Assignee: GM Global Technology Operations LLC
    Inventors: Suresh Gopalakrishnan, Lei Hao, Chandra S. Namuduri, Paul S. Lombardo, Jeffrey R. Aldrich, Chunhao J. Lee, Neeraj S. Shidore
  • Publication number: 20200313586
    Abstract: A method of controlling an interior permanent magnet (IPM) motor includes receiving a motor torque command, and selecting a nominal d-axis current and a nominal q-axis current stored in a first lookup table. The nominal d-axis current and the nominal q-axis current correspond with a predetermined efficiency of the IPM motor at a nominal temperature and are based on at least the motor torque command and magnetic flux at a nominal temperature of the IPM motor. A d-axis adjustment current and a q-axis adjustment current are then selected from a stored second lookup table. The adjustment currents correspond with the predetermined efficiency of the IPM motor and are based at least on the magnetic flux and an operating temperature of the IPM motor. A corrected d-axis current and a corrected q-axis current are commanded. The corrected currents are the sum of the respective nominal current and adjustment current.
    Type: Application
    Filed: March 26, 2019
    Publication date: October 1, 2020
    Applicant: GM Global Technology Operations LLC
    Inventors: Suresh Gopalakrishnan, Anno Yoo, Wesley G. Zanardelli, Yo Chan Son
  • Publication number: 20200280197
    Abstract: A battery includes: a first terminal; a second terminal; a plurality of individually housed batteries; a plurality of switches configured to connect ones of the individually housed batteries to and from ones of the first and second terminals; and a switch control module configured to: at a frequency, vary a voltage applied to a gate of one of the switches, the one of the switches configured to connect at least one of the individually housed batteries to one of the first and second terminals; and diagnose whether a fault is present in the one of the switches based on a voltage across the one of the switches.
    Type: Application
    Filed: March 1, 2019
    Publication date: September 3, 2020
    Inventors: Lyall K. WINGER, Dave G. RICH, Suresh GOPALAKRISHNAN, Chandra S. NAMUDURI
  • Publication number: 20200278936
    Abstract: A modular dynamically allocated capacity storage system (MODACS) is provided and includes a housing and a control module. The housing includes source terminals, switches, cells, and sensing module. The source terminals supplying power at a first voltage potential to a first plurality of loads and power at a second voltage potential to a second plurality of loads. The cells are configured to supply power to each of the source terminals based on states of the switches. The sensing modules are configured to determine parameters of each of the cells and generate corresponding status signals. The control module is configured to receive a power request signal, and based on the power request signal and the parameters of each of the cells, determine a connected configuration for the cells relative to each other and the plurality of source terminals and set states of the switches according to the connected configuration.
    Type: Application
    Filed: March 1, 2019
    Publication date: September 3, 2020
    Inventors: Suresh GOPALAKRISHNAN, Chandra S. NAMUDURI, Lyall K. WINGER, Dave G. RICH
  • Patent number: 10759298
    Abstract: Presented are intelligent vehicle systems and control logic for predictive charge planning and powertrain control of electric-drive vehicles, methods for manufacturing/operating such systems, and electric-drive vehicles with smart charge planning and powertrain control capabilities. Systems and methods of AI-based predictive charge planning for smart electric vehicles use machine-learning (ML) driver models that draws on available traffic, location, and roadway map information to estimate vehicle speed and propulsion torque requirements to derive a total energy consumption for a given trip. Systems and methods of AI-based predictive powertrain control for smart hybrid vehicles use ML driver models with deep learning techniques to derive a drive cycle profile defined by a preview route with available traffic, geopositional, geospatial, and map data.
    Type: Grant
    Filed: August 29, 2018
    Date of Patent: September 1, 2020
    Assignee: GM Global Technology Operations LLC
    Inventors: Yue-Yun Wang, Junfeng Zhao, Suresh Gopalakrishnan, Yiran Hu, Norman K. Bucknor
  • Patent number: 10724491
    Abstract: An electric starter system is used with an engine. The starter system may include a solenoid device coupled to a pinion gear, a brushless starter motor connectable to the engine via the pinion gear during a requested engine start event, and a controller. In response to the start event, when the engine speed is less than a threshold speed, the controller delivers a control current to the solenoid device at a peak current level sufficient for translating the pinion gear into contact with the flywheel. The control current is reduced to a holding current level less than the peak current level after the pinion gear is engaged with the flywheel. Motor torque is commanded from the starter motor, through the pinion gear, and to the flywheel while maintaining the holding current level, and held for a duration sufficient for starting the engine.
    Type: Grant
    Filed: May 1, 2018
    Date of Patent: July 28, 2020
    Assignee: GM Global Technology Operations LLC
    Inventors: Chandra S. Namuduri, Kenneth J. Shoemaker, Chunhao J. Lee, Lei Hao, Thomas W. Nehl, Suresh Gopalakrishnan
  • Publication number: 20200235440
    Abstract: Presented are battery pack voltage-switching (“V-switch”) systems, methods for making/operating such systems, and multi-pack, electric-drive motor vehicles with battery pack V-switch capabilities. A method for controlling operation of a vehicle includes a vehicle controller receiving a voltage switch signal to change a voltage output of the vehicle's battery system. The vehicle controller determines if a speed of a traction motor is less than a calibrated base speed; if so, the controller transmits a pack isolation signal to a power inverter to electrically disconnect the traction battery packs from the traction motor. The vehicle controller determines if a bus current of a DC bus is less than a calibrated bus current threshold; if so, the controller transmits an open signal to open one or more pack contactor switches and a close signal to close one or more pack contactor switches thereby causing the vehicle battery system to output the second voltage.
    Type: Application
    Filed: January 18, 2019
    Publication date: July 23, 2020
    Applicant: GM Global Technology Operations LLC
    Inventors: Lei Hao, Yue-Yun Wang, Chandra S. Namuduri, Suresh Gopalakrishnan, Thomas W. Nehl, Dongxu Li