Patents by Inventor Chandra S. Namuduri

Chandra S. Namuduri 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: 20240380334
    Abstract: A multilevel inverter includes a set of inverter switches arranged in a multilevel inverter topology. The multilevel inverter topology has a high voltage (V) input, a low voltage input and an intermediate voltage input. A first voltage source connects the high voltage input to the intermediate voltage input and a second voltage source connects the intermediate voltage input to the low voltage source.
    Type: Application
    Filed: May 10, 2023
    Publication date: November 14, 2024
    Inventors: Muhammad Hussain Alvi, Renato Amorim Torres, Chandra S. Namuduri, Rashmi Prasad
  • Patent number: 12142960
    Abstract: A method and apparatus for electrical energy transfer between a pair of series connected batteries coupled between positive and negative DC rails of a power inverter operatively connected to a plurality of stator phase windings of a stator winding of a motor may include coupling a midpoint of the pair of series connected batteries to the stator winding of the motor, and controlling the power inverter to operate the power inverter and the stator winding as a switched-mode power converter to charge at least one of the stator phase windings from one of the pair of series connected batteries and to discharge the at least one of the stator phase windings to the other of the pair of series connected batteries.
    Type: Grant
    Filed: June 14, 2022
    Date of Patent: November 12, 2024
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Mohamed Kamel, Muhammad Hussain Alvi, Alireza Fatemi, Chandra S. Namuduri, Rashmi Prasad
  • Patent number: 12139040
    Abstract: An electric drive system for an electric vehicle is provided. The electric drive system includes a first electric drive, a second electric drive, and a switchable battery including at least two battery packs that are selectively arranged in one of a series configuration and a parallel configuration. The electric drive system also includes a first half-bridge buck converter connecting the first electric drive to a first battery back of the at least two battery packs of the switchable battery and a second half-bridge buck converter connecting the second electric drive to a second battery back of the at least two battery packs of the switchable battery. The electric drive system further includes a controller configured to control the configuration of the switchable battery, an operation of the first half-bridge buck converter, and the second half-bridge buck converter.
    Type: Grant
    Filed: December 7, 2022
    Date of Patent: November 12, 2024
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Muhammad Hussain Alvi, Suresh Gopalakrishnan, Chandra S. Namuduri
  • Publication number: 20240367552
    Abstract: A method and apparatus for heating a battery pack in an electrified vehicle provides a zero d-axis current command and a zero q-axis current command to a field-oriented controller for an alternating current (AC) motor coupled to the battery pack through a power inverter module controlled by the field-oriented controller. An AC signal is injected onto the d-axis of the field-oriented controller resulting in an AC current through the battery pack effecting AC resistance heating.
    Type: Application
    Filed: May 3, 2023
    Publication date: November 7, 2024
    Inventors: Renato Amorim Torres, Lei Hao, Suresh Gopalakrishnan, Chandra S. Namuduri, Dongxu Li
  • Publication number: 20240367549
    Abstract: An energy transfer system includes a conversion device configured for partial power processing and configured to regulate current from a first battery system, and a controller configured to control the conversion device to adjust a first voltage of the first battery system to conform the first voltage to a second voltage of a second battery system, the second battery system connected in parallel with the first battery system by a bus. The conversion device is configured to receive power from the first battery system, cause a selected portion of the power to flow through a conversion stage to adjust the first voltage, the selected portion corresponding to a difference between the first voltage and the second voltage, cause a remaining portion of the power to flow directly to the bus and bypass the conversion stage, and output a current from the conversion device at the second voltage.
    Type: Application
    Filed: May 2, 2023
    Publication date: November 7, 2024
    Inventors: Mohamed Ahmed Kamel Ahmed, Lei Hao, Chandra S. Namuduri
  • Patent number: 12136846
    Abstract: Electrical energy is transferred between an on-vehicle DC power source and an off-vehicle DC power source by controlling conduction of the phase legs of a power inverter to operatively configure the power inverter and the stator phase windings of a traction motor as a switched-mode power converter including the at least one phase winding and at least one switch of one of the phase legs.
    Type: Grant
    Filed: May 13, 2022
    Date of Patent: November 5, 2024
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Rashmi Prasad, Chandra S. Namuduri, Avoki M. Omekanda
  • Patent number: 12136805
    Abstract: A vehicle, arc fault protection device of the vehicle and a method for mitigating an arc fault in an electrical system of the vehicle. The arc fault protection device includes a sensor, a switch, and a processor. The sensor is used for measuring a current in an electrical system. The processor is configured to determine a precursor phase of an arc fault from the current, wherein the precursor phase indicates an onset of an arc flash phase of the arc fault. The processor opens the switch to mitigate the arc fault during the arc flash phase.
    Type: Grant
    Filed: August 16, 2022
    Date of Patent: November 5, 2024
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Suresh Gopalakrishnan, Muhammad Hussain Alvi, Chandra S. Namuduri, Lyall Kenneth Winger, James Morrison, Xinyu Du
  • Publication number: 20240363288
    Abstract: Aspects of the disclosure include a symmetric direct current (DC) link capacitor having a low parasitic equivalent series L-inductance (ESL). An exemplary capacitor can include one or more positive-dielectric-negative (PDN) stacks having a positive layer, a negative layer, and a dielectric layer between the positive layer and the negative layer. A first contact layer is electrically coupled to the positive layer on a sidewall of the one or more PDN stacks and a second contact layer is electrically coupled to the negative layer on the sidewall of the one or more PDN stacks. A positive terminal is electrically coupled to the first contact layer and a negative terminal is electrically coupled to the second contact layer.
    Type: Application
    Filed: April 27, 2023
    Publication date: October 31, 2024
    Inventors: Junghoon Kim, Muhammad Hussain Alvi, Rashmi Prasad, Chandra S. Namuduri, Yilun Luo
  • Publication number: 20240359596
    Abstract: A vehicle having an ambient temperature sensor, a low voltage lithium-ion battery and a controller is provided. The controller is configured to monitor the ambient temperature sensor and based on a determination that an ambient temperature is below a threshold value, provide an alternating current power to the low voltage lithium-ion battery. The alternating current power causes the low voltage lithium-ion battery to heat.
    Type: Application
    Filed: April 26, 2023
    Publication date: October 31, 2024
    Inventors: Suresh Gopalakrishnan, Neeraj S. Shidore, Chandra S. Namuduri, Lei Hao, Satish P. Ketkar, Christian Fau, Lyall Kenneth Winger
  • Publication number: 20240351473
    Abstract: An electric vehicle, system and method of charge transfer at the electric vehicle. The vehicle includes a charging circuit and a processor. The charging circuit includes a first battery, a second battery and a motor winding. The processor determines a desired reference current of the motor winding, a first voltage of the first battery and a second voltage of the second battery, calculates a power loss for each of a plurality of conduction modes based on the desired reference current, the first voltage and the second voltage, wherein each of the plurality of conduction modes transfers charge between the first battery and the second battery, selects a conduction mode from the plurality of conduction modes that has a least power loss, establishes a duty cycle parameter for the selected mode, and applies the conduction mode and the duty cycle parameter to the charging circuit to transfer the charge.
    Type: Application
    Filed: April 20, 2023
    Publication date: October 24, 2024
    Inventors: Mohamed Ahmed Kamel Ahmed, Chandra S. Namuduri
  • Publication number: 20240356361
    Abstract: An electric vehicle includes a system performing a method of charging a battery of the electric vehicle. The system includes an electrical motor having a rotor and a plurality of windings. The vehicle is turned off to allow the rotor to come to rest at an initial rotor position. The processor controls a current through the motor to rotate the rotor to locate a boundary of an electrical lash region associated with the rotor, determines a selected winding of the plurality of windings having a phase vector located close to the electrical lash region, deactivates the selected winding, controls flow of a first current through the motor with the selected winding deactivated to rotate the rotor towards a direction of the selected winding, and controls flow of a second current from a charging station to the battery through the electric motor with the rotor rotated towards the selected winding.
    Type: Application
    Filed: April 20, 2023
    Publication date: October 24, 2024
    Inventors: Dongxu Li, Minh-Khai Nguyen, Avoki M. Omekanda, Chandra S. Namuduri, Rashmi Prasad, Lei Hao
  • Publication number: 20240356362
    Abstract: A charging system of a vehicle includes a charging device configured to transfer an electric charge between a battery system of the vehicle and a recipient energy storage system, the charging device including a plurality of conversion stages. The charging system also includes a switching system configured to selectively bypass one or more conversion stages during a charging process, the charging process including transferring electric charge from the battery system to the recipient energy storage system, and a first controller configured to operate the switching system based on a voltage range of a recipient charge port of the recipient energy storage system.
    Type: Application
    Filed: April 19, 2023
    Publication date: October 24, 2024
    Inventors: Chandra S. Namuduri, Rashmi Prasad
  • Publication number: 20240348113
    Abstract: An electric propulsion motor system includes a cylindrical stator and rotor, a fluid circulation system providing pressurized fluid, and conductors within winding slots. The stator has a yoke and a plurality of teeth extending radially inward from the yoke, with winding slots defined between adjacent teeth. Respective tooth tips extend circumferentially into adjacent winding slots and are radially adjacent to a first conductor within the winding slot, with a first channel through which pressurized fluid flows.
    Type: Application
    Filed: April 14, 2023
    Publication date: October 17, 2024
    Inventors: Alireza Fatemi, Farzad Samie, Thomas W. Nehl, Chandra S. Namuduri, Gokhan Cakal
  • Publication number: 20240339990
    Abstract: Power converters on a vehicle may provide electrical power to propulsion and non-propulsion vehicle systems from a battery source. Power converters may include DC link capacitors. An electronically resettable fuse may pass electric current between the battery source and the power converters through a switch module. The switch module may be controlled in a pre-charge mode and a circuit protection mode, wherein the pre-charge mode limits a rate of charging of the DC link capacitor by controlling the electric current with the switch module.
    Type: Application
    Filed: April 6, 2023
    Publication date: October 10, 2024
    Inventors: Chandra S. Namuduri, Rashmi Prasad, Muhammad Hussain Alvi
  • Patent number: 12113468
    Abstract: A system for controlling an electric motor includes a voltage regulation device connected to the electric motor, the electric motor connected to an inverter by a power cable including at least one electrical conductor. The voltage regulation device includes a diode bridge circuit configured to mitigate overvoltage transients at the electric motor. The diode bridge circuit includes an alternating current (AC) input and a direct current (DC) output, the AC input connected to a terminal of the electric motor.
    Type: Grant
    Filed: November 14, 2022
    Date of Patent: October 8, 2024
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Chandra S. Namuduri, Suresh Gopalakrishnan
  • Patent number: 12107454
    Abstract: A charging system of a vehicle includes a charging device configured to transfer an electric charge between a battery system of the vehicle and a recipient energy storage system, the charging device including a plurality of conversion stages. The charging system also includes a switching system configured to selectively bypass one or more conversion stages during a charging process, the charging process including transferring electric charge from the battery system to the recipient energy storage system, and a first controller configured to operate the switching system based on a voltage range of a recipient charge port of the recipient energy storage system.
    Type: Grant
    Filed: April 19, 2023
    Date of Patent: October 1, 2024
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Chandra S. Namuduri, Rashmi Prasad
  • Patent number: 12097784
    Abstract: Fuse configurations for a distributed power architecture of a vehicle is provided. The distributed power architecture includes a high-voltage battery pack having a plurality of batteries and a plurality of converters, each of the plurality of converters being configured to receive high-voltage power from one of the plurality of batteries and to provide low-voltage power to a low-voltage bus. The distributed power architecture also includes a plurality of fuses disposed on one or more of an input side and an output side of each of the plurality of converters and a vehicle controller with at least one communication link to each of the plurality of power converters. Each of the plurality of fuses are configured to selectively prevent current flow through one of the plurality of converters.
    Type: Grant
    Filed: February 9, 2023
    Date of Patent: September 24, 2024
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Mohamed Kamel, Chandra S. Namuduri, Rashmi Prasad, Jun-mo Kang, Muhammad Hussain Alvi
  • Publication number: 20240308379
    Abstract: A vehicle, system and method of charging the vehicle. The vehicle includes a battery, a first electric motor coupled to the battery, a second electric motor coupled to the battery, and a switch for forming a circuit between a charging station and the battery through the first electric motor and the second electric motor. A processor controls a configuration of the switch and commences charging of the battery from the charging station through the first electric motor and the second electric motor.
    Type: Application
    Filed: March 16, 2023
    Publication date: September 19, 2024
    Inventors: Rashmi Prasad, Minh-Khai Nguyen, Chandra S. Namuduri
  • Patent number: 12095352
    Abstract: A power control system for an electric vehicle comprises N power inverters configured to connect to a battery system of the electric vehicle. Each of the N power inverters includes a plurality of power switches, where N is an integer greater than one. The N power inverters are configured to connect to stator phase windings of N electric machines, respectively. A controller is configured to determine a switching frequency for the N electric machines and (N?1) phase offsets for (N?1) ones of the N electric machines, generate a set of pulse width modulation (PWM) switching signals at the switching frequency for a first one of the N power inverters, and output (N?1) sets of PWM switching signals to the (N?1) ones of the N electric machines based on the set of PWM switching signals and the (N?1) phase offsets.
    Type: Grant
    Filed: May 27, 2022
    Date of Patent: September 17, 2024
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Chandra S. Namuduri, Suresh Gopalakrishnan, Lei Hao
  • Publication number: 20240297516
    Abstract: A system for supplying power to one or more electrical loads in a vehicle includes a conversion system connected to a battery system, the battery system configured to provide a voltage to a propulsion system of the vehicle via a propulsion bus, the conversion system including a conversion device and a pre-charge circuit selectively connected to the propulsion bus by a first switch, the conversion system selectively connected to the one or more electrical loads. The system also includes a controller configured to operate the conversion system to electrically connect the conversion device and the pre-charge circuit to the battery system and the one or more electrical loads, the controller configured to adjust a battery system voltage from the battery system to a load voltage of the one or more electrical loads based on a mismatch between the battery system voltage and the load voltage.
    Type: Application
    Filed: March 2, 2023
    Publication date: September 5, 2024
    Inventors: Chunhao J. Lee, Dongxu Li, Suresh Gopalakrishnan, Lei Hao, Chandra S. Namuduri