Patents by Inventor Rashmi Prasad

Rashmi Prasad 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: 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
  • 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: 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: 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: 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: 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
  • Publication number: 20240270120
    Abstract: An optimal control strategy for a distributed low voltage system with bidirectional DC/DC converters is provided. A vehicle system includes DC/DC converters configured to receive electrical currents from high voltage battery modules and output regulating electrical currents to a low voltage battery. The vehicle system includes a control system coupled to the DC/DC converters, the high voltage battery modules, and the low voltage battery, where the control system is configured to control the DC/DC converters to recirculate one or more of the electrical currents back to one or more of the high voltage battery modules in order to balance states of charge in the high voltage battery modules.
    Type: Application
    Filed: February 15, 2023
    Publication date: August 15, 2024
    Inventors: Jun-mo Kang, Muhammad Hussain Alvi, Mohamed Ahmed Kamel Ahmed, Rashmi Prasad
  • Publication number: 20240270118
    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: Application
    Filed: February 9, 2023
    Publication date: August 15, 2024
    Inventors: Mohamed Kamel, Chandra S. Namuduri, Rashmi Prasad, Jun-mo Kang, Muhammad Hussain Alvi
  • Publication number: 20240243596
    Abstract: A battery system for a vehicle includes multiple battery cells each configured to store charge for powering an electric vehicle, a high voltage bus electrically coupled with the multiple battery cells to provide power to an electric motor, and multiple cell monitoring modules each coupled with a corresponding one of the multiple battery cells, each cell monitoring module including a controller configured to monitor operation parameters of the corresponding one of the multiple battery cells. The system includes multiple DC-DC converters in a converter housing, each DC-DC converter electrically coupled with a corresponding one of the multiple battery cells outside of the converter housing, and a low voltage bus electrically connected between the multiple DC-DC converters in the converter housing and at least one vehicle electrical component outside of the converter housing. The low voltage bus is configured to provide low voltage power to at least one vehicle electrical component.
    Type: Application
    Filed: January 13, 2023
    Publication date: July 18, 2024
    Inventors: Rashmi PRASAD, Mohamed Ahmed Kamel AHMED, Chandra S. NAMUDURI, Jun-mo KANG
  • Publication number: 20240243667
    Abstract: An energy storage system includes a plurality of batteries coupled in series, a plurality of first isolated DC-DC power converters each having first and second sides, a DC bus coupled to the second sides of the plurality of first isolated DC-DC power converters, and a second isolated DC-DC power converter coupled in parallel with the plurality of first isolated DC-DC power converters. Each of the first sides of the plurality of first isolated DC-DC power converters is coupled to at least one of the batteries. The second isolated DC-DC power converter includes a first side coupled to the plurality of batteries and a second side coupled to the DC bus. The second isolated DC-DC power converter is configured to mitigate a transient load condition on the DC bus.
    Type: Application
    Filed: January 16, 2023
    Publication date: July 18, 2024
    Inventors: Mohamed Ahmed Kamel AHMED, Chandra S. Namuduri, Rashmi Prasad, Suresh Gopalakrishnan, Lyall Kenneth Winger
  • Patent number: 12036884
    Abstract: A charging system includes a scalable power source for powering a motor of a vehicle and telematics and battery management modules. The scalable power source includes: N battery packs, where N is an integer greater than or equal to 3; and multiple switches connected to the N battery packs including N?1 switches for serially connecting the N battery packs between supply and return lines and a multiple of N switches for parallel connecting the N battery packs to the supply and return lines. The telematics module requests capability of a charging station and receives a response signal from a device indicating the capability of the charging station. The battery management module: based on the capability of the charging station, selects one of the available arrangements in which to connect the N battery packs, sets states of the multiple switches; and then charges the N battery packs based on the states.
    Type: Grant
    Filed: June 17, 2021
    Date of Patent: July 16, 2024
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Rashmi Prasad, Chandra S. Namuduri, Suresh Gopalakrishnan, Thomas W. Nehl, David J. Brooks
  • Publication number: 20240234238
    Abstract: Aspects of the disclosure include a power module having enhanced thermal management. An exemplary power module can include a direct bond copper (DBC) substrate having a top copper layer, a bottom copper layer, and a dielectric layer between the top copper layer and the bottom copper layer. The power module includes a thin-film thermoelectric cooler (TFTEC) having a thermoelectric film positioned between a top insulator and a bottom insulator. One or more dies are positioned over the DBC substrate and the TFTEC and a controller is configured to adjust a thermoelectric device current of the TFTEC responsive to a temperature of the one or more dies.
    Type: Application
    Filed: January 5, 2023
    Publication date: July 11, 2024
    Inventors: Chandra S. Namuduri, Rashmi Prasad
  • Patent number: 12034324
    Abstract: An electrified vehicle may include a plurality of electric drive units, a plurality of battery packs, a plurality of charge ports and a plurality of controllable switches. The switches may be controlled to flexibly configure power transfer into and out of the vehicle through one or more charge ports affecting one or more battery packs in parallel or individually passively or actively through inverter integrated converter charge transfer.
    Type: Grant
    Filed: October 28, 2022
    Date of Patent: July 9, 2024
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Chandra S. Namuduri, Rashmi Prasad, Minh-Khai Nguyen
  • Patent number: 12027900
    Abstract: A battery system for a vehicle includes multiple battery cells each configured to store charge for powering an electric vehicle, a high voltage bus electrically coupled with the multiple battery cells to provide power to an electric motor, and multiple cell monitoring modules each coupled with a corresponding one of the multiple battery cells, each cell monitoring module including a controller configured to monitor operation parameters of the corresponding one of the multiple battery cells. The system includes multiple DC-DC converters in a converter housing, each DC-DC converter electrically coupled with a corresponding one of the multiple battery cells outside of the converter housing, and a low voltage bus electrically connected between the multiple DC-DC converters in the converter housing and at least one vehicle electrical component outside of the converter housing. The low voltage bus is configured to provide low voltage power to at least one vehicle electrical component.
    Type: Grant
    Filed: January 13, 2023
    Date of Patent: July 2, 2024
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Rashmi Prasad, Mohamed Ahmed Kamel Ahmed, Chandra S. Namuduri, Jun-mo Kang
  • Patent number: 12012006
    Abstract: A battery electric system for a motor vehicle or another electrified system includes a battery pack connected to a direct current voltage bus, and having positive and negative battery terminals, a main pyrotechnic fuse (“pyro fuse”), a high-voltage (HV) component connected to the bus via an HV channel, a current sensing element connected to the HV component on the HV channel, and a control system configured to selectively disconnect the battery pack from the bus by transmitting a voltage signal to the main pyro fuse when a measured current value from the current sensor is indicative of a short-circuit fault. A channel switch may be connected to or integral with the current sensing element, and configured to disconnect the HV component from the bus by opening in response to the measured current value.
    Type: Grant
    Filed: March 11, 2022
    Date of Patent: June 18, 2024
    Assignee: GM Global Technology Operations LLC
    Inventors: Rashmi Prasad, Robert J. Heydel, Andrew K. Chandler, Shubham V. Shedge, Chandra S. Namuduri, Eleni C. Pitses
  • Patent number: 12009715
    Abstract: A method includes: selectively actuating switches of an inverter module and first, second, third, and fourth switches of a motor; and charging a battery with power from a charger using at least one of first, second, and third stator windings of the motor, the battery having a first voltage and being electrically connected in parallel with the inverter module, and the charger having a second voltage that is less than the first voltage.
    Type: Grant
    Filed: April 26, 2022
    Date of Patent: June 11, 2024
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Rashmi Prasad, Chandra S. Namuduri, Lei Hao, Suresh Gopalakrishnan