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).

  • Patent number: 11658474
    Abstract: Examples described herein provide a computer-implemented method that includes monitoring, using a microcontroller, an electric circuit of a vehicle, the electric comprising a battery source and a load. The battery source supplies electric power to the load. The method further includes detecting, using the microcontroller, a high current event in the electric circuit by comparing a current level of a current flowing through the electric circuit to a time-based current threshold. The method further includes responsive to detecting the high current event, controlling a gate driver to cause a switch of an electronically resettable fuse to open the electric circuit to stop the flow of the current through the electric circuit.
    Type: Grant
    Filed: September 7, 2021
    Date of Patent: May 23, 2023
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Chandra S. Namuduri, Muhammad Hussain Alvi, Rashmi Prasad
  • Patent number: 11607967
    Abstract: An example of a vehicle electrical system includes a rechargeable energy storage system (RESS) having a first voltage and a power inverter selectively connected to the RESS. The system further includes an electric motor having a plurality of machine windings with each of the machine windings including a polyphase terminal electrically connected to the power inverter. The machine windings further include a neutral terminal separate from the polyphase terminals and configured to electrically connect to an off-board power source having a second voltage that is below the first voltage of the RESS. The power inverter is configured to cycle between first and second operational states, such that the power inverter and the electric motor steps up the first voltage to the second voltage.
    Type: Grant
    Filed: March 22, 2021
    Date of Patent: March 21, 2023
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Rashmi Prasad, Chandra S. Namuduri
  • Publication number: 20230073390
    Abstract: Examples described herein provide a computer-implemented method that includes monitoring, using a microcontroller, an electric circuit of a vehicle, the electric comprising a battery source and a load. The battery source supplies electric power to the load. The method further includes detecting, using the microcontroller, a high current event in the electric circuit by comparing a current level of a current flowing through the electric circuit to a time-based current threshold. The method further includes responsive to detecting the high current event, controlling a gate driver to cause a switch of an electronically resettable fuse to open the electric circuit to stop the flow of the current through the electric circuit.
    Type: Application
    Filed: September 7, 2021
    Publication date: March 9, 2023
    Inventors: Chandra S. Namuduri, Muhammad Hussain Alvi, Rashmi Prasad
  • Publication number: 20230068153
    Abstract: A rechargeable energy storage system (RESS) includes a battery controller and battery modules, each respective module having battery cells, a cell sense board, and a semiconductor switch. The switch is connected in parallel with the cells within the respective module, and configured to conduct an electrical current during a thermal runaway propagation (TRP) event in which one or more cells is in an open-circuit state. This action bypasses the module and enables electrical components to be powered by the RESS during the TRP event. A battery electric system includes a direct current (“DC”) voltage bus, an electrical component connected thereto, the battery controller, and the RESS. A method for constructing the RESS includes connecting a respective semiconductor switch in parallel with the at least one battery cell of each respective one of the multiple battery modules, and electrically connecting the multiple battery modules together to construct the RESS.
    Type: Application
    Filed: September 1, 2021
    Publication date: March 2, 2023
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Rashmi Prasad, Chandra S. Namuduri, Robert J. Heydel, Russell K. Steele
  • Patent number: 11581841
    Abstract: An electrical system can include a rechargeable energy storage system (RESS) and a power inverter connected to the RESS. The power inverter can be configured to provide electrical power to a traction motor. The electrical system includes a plurality of machine windings connected between a plurality of first switches and the traction motor. Each switch of the plurality of first switches is configured to transition between a closed state to allow current flow between the power inverter and the traction motor. The electrical system includes a plurality of inductor windings connected between a plurality of second switches and an off-board power source. Each switch of the plurality of second switches is configured to transition between a closed state to allow current flow between the off-board power source and the power inverter to charge the RESS.
    Type: Grant
    Filed: March 22, 2021
    Date of Patent: February 14, 2023
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Rashmi Prasad, Chandra S. Namuduri
  • Patent number: 11569745
    Abstract: An example electrical system is disclosed. The electrical system can include a rechargeable energy storage system (RESS) and a power inverter connected to the RESS. The power inverter can be configured to provide electrical power to a traction motor. The electrical system can include a plurality of machine windings connected between the power inverter and a switch. The switch can be configured to transition between a closed state to allow current flow from an off-board power source through the plurality of machine windings to the RESS and an open state to prevent current flow between the off-board power source and the plurality of machine windings.
    Type: Grant
    Filed: March 22, 2021
    Date of Patent: January 31, 2023
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Rashmi Prasad, Chandra S. Namuduri
  • Publication number: 20220402395
    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: Application
    Filed: June 17, 2021
    Publication date: December 22, 2022
    Inventors: Rashmi PRASAD, Chandra S. NAMUDURI, Suresh GOPALAKRISHNAN, Thomas W. NEHL, David J. BROOKS
  • Publication number: 20220355703
    Abstract: An electric propulsion system includes a rotary electric machine having an output member, a rechargeable energy storage system (“RESS”) connected to the electric machine, a user interface device, and a controller. The RESS includes multiple battery modules and a switching circuit, the latter being configured, in response to electronic switching control signals, to connect the battery modules in a parallel-connected (“P-connected”) configuration or a series-connected (“S-connected”) configuration, as a selected battery configuration. The user interface device receives an operator-requested drive mode signal indicative of a desired drive mode of the electric propulsion system.
    Type: Application
    Filed: May 6, 2021
    Publication date: November 10, 2022
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Alireza Fatemi, Thomas W. Nehl, Chandra S. Namuduri, Lei Hao, Norman K. Bucknor, Rashmi Prasad
  • Publication number: 20220340026
    Abstract: A battery charging system includes: an electric motor including stator coils; a battery; a charge port configured to receive power from charging stations by wire; first and second electrical conductors connected between the battery and the charge port; an inverter module including (a) inputs connected to receive power from the battery and (b) outputs connected to the electric motor; a third electrical conductor; and a switch configured to electrically connect and disconnect a first end of the third electrical conductor to and from the first electrical conductor, where the third electrical conductor includes a second end that is connected to at least one of the stator coils via one of the outputs of the inverter module.
    Type: Application
    Filed: April 23, 2021
    Publication date: October 27, 2022
    Inventors: Rashmi Prasad, Chandra S. Namuduri
  • Patent number: 11476507
    Abstract: A solid-state switch assembly includes a base plate and an electrically insulating layer affixed to the base plate. First, second, third, and fourth power traces are affixed to the electrically insulating layer. First semiconductor devices are arranged on the first power trace to control power flow between the first power trace and the second power trace, second semiconductor devices are arranged on the second power trace to control power flow between the second power trace and the third power trace, and third semiconductor devices are arranged on the third power trace to control power flow between the third and fourth power traces. A first signal conductor communicates with the first semiconductor devices. A second signal conductor communicates with the second semiconductor devices. A third signal conductor communicates with the third semiconductor devices.
    Type: Grant
    Filed: March 16, 2020
    Date of Patent: October 18, 2022
    Assignee: GM Global Technology Operations LLC
    Inventors: Chandra S. Namuduri, Rashmi Prasad
  • Publication number: 20220328270
    Abstract: A solid-state fuse device includes a switch a gate driver connected to the switch and configured to transition the switch from a closed state to an open state when at least one of an overcurrent measurement exceeds a predetermined overcurrent threshold or a voltage drop across the switch exceeds a predetermined saturation voltage threshold.
    Type: Application
    Filed: April 7, 2021
    Publication date: October 13, 2022
    Inventors: Chandra S. Namuduri, Muhammad H. Alvi, Rashmi Prasad
  • Publication number: 20220310481
    Abstract: A power module is provided and includes first stack, second stack, and third stacks of layers, a heat pipe, and at least one cold plate or heat sink. The third stack of layers is disposed between the first stack of layers and the second stack of layers and includes a first semiconductor die, a second semiconductor die and a center spacer layer disposed between the first semiconductor die and the second semiconductor die. The heat pipe extends at least partially into the center spacer layer. The at least one cold plate or heat sink receives thermal energy from the first stack of layers and the second stack of layers. The second stack of layers, the third stack of layers, the heat pipe and the at least one cold plate or heat sink facilitate dual sided cooling of each of the first semiconductor die and the second semiconductor die.
    Type: Application
    Filed: March 29, 2021
    Publication date: September 29, 2022
    Inventors: Muhammad H. ALVI, Ming LIU, Rashmi PRASAD, Anthony M. COPPOLA
  • Publication number: 20220297557
    Abstract: An example of a vehicle electrical system includes a rechargeable energy storage system (RESS) having a first voltage and a power inverter selectively connected to the RESS. The system further includes an electric motor having a plurality of machine windings with each of the machine windings including a polyphase terminal electrically connected to the power inverter. The machine windings further include a neutral terminal separate from the polyphase terminals and configured to electrically connect to an off-board power source having a second voltage that is below the first voltage of the RESS. The power inverter is configured to cycle between first and second operational states, such that the power inverter and the electric motor steps up the first voltage to the second voltage.
    Type: Application
    Filed: March 22, 2021
    Publication date: September 22, 2022
    Inventors: Rashmi Prasad, Chandra S. Namuduri
  • Publication number: 20220302835
    Abstract: An example electrical system is disclosed. The electrical system can include a rechargeable energy storage system (RESS) and a power inverter connected to the RESS. The power inverter can be configured to provide electrical power to an electric machine. A switch can be disposed between the plurality of machine windings and an output load. The switch is configured to transition between a closed state to allow current flow from the RESS through the inverter and the plurality of machine windings to the output load and an open state to prevent current flow to the output load.
    Type: Application
    Filed: March 22, 2021
    Publication date: September 22, 2022
    Inventors: Rashmi Prasad, Chandra S. Namuduri
  • Publication number: 20220304180
    Abstract: A busbar assembly includes a base having a width and a length. The base has a first surface and a second surface and has a first side and a second side. A distance between the first side and the second side comprises the width, and the base defines a slot centered between approximately 75% and approximately 79% of the width.
    Type: Application
    Filed: June 13, 2022
    Publication date: September 22, 2022
    Inventors: Muhammad H. Alvi, Rashmi Prasad, Chandra S. Namuduri
  • Publication number: 20220297555
    Abstract: An example of a vehicle electrical system includes a rechargeable energy storage system (RESS) having a first voltage and a power inverter electrically connected to the RESS. The system further includes an electric motor having a plurality of machine windings with each of the machine windings including a polyphase terminal electrically connected to the power inverter. The electric motor further includes a neutral terminal separate from the polyphase terminals. The system further includes an accessory load electrically connected to the power inverter and the neutral terminal of the electric motor, with the accessory load requiring a second voltage that is below the first voltage. A current flows through the machine windings to step down the first voltage to the second voltage. The power inverter is configured to cycle between first and second operational states, such that the power inverter steps down the first voltage to the second voltage.
    Type: Application
    Filed: March 22, 2021
    Publication date: September 22, 2022
    Inventors: Rashmi Prasad, Chandra S. Namuduri
  • Publication number: 20220302867
    Abstract: An electrical system can include a rechargeable energy storage system (RESS) and a power inverter connected to the RESS. The power inverter can be configured to provide electrical power to a traction motor. The electrical system includes a plurality of machine windings connected between a plurality of first switches and the traction motor. Each switch of the plurality of first switches is configured to transition between a closed state to allow current flow between the power inverter and the traction motor. The electrical system includes a plurality of inductor windings connected between a plurality of second switches and an off-board power source. Each switch of the plurality of second switches is configured to transition between a closed state to allow current flow between the off-board power source and the power inverter to charge the RESS.
    Type: Application
    Filed: March 22, 2021
    Publication date: September 22, 2022
    Inventors: Rashmi Prasad, Chandra S. Namuduri
  • Publication number: 20220302836
    Abstract: An example electrical system is disclosed. The electrical system can include a rechargeable energy storage system (RESS) and a power inverter connected to the RESS. The power inverter can be configured to provide electrical power to a traction motor. The electrical system can include a plurality of machine windings connected between the power inverter and a switch. The switch can be configured to transition between a closed state to allow current flow from an off-board power source through the plurality of machine windings to the RESS and an open state to prevent current flow between the off-board power source and the plurality of machine windings.
    Type: Application
    Filed: March 22, 2021
    Publication date: September 22, 2022
    Inventors: Rashmi Prasad, Chandra S. Namuduri
  • Patent number: 11444474
    Abstract: A mobile power source apparatus includes a mobile unit having a platform structure, a frame connected to the platform structure and multiple wheels rotatably connected to the platform structure to promote moving the mobile unit. An electronics power module is connected to a DC power source defining a high voltage DC battery. The electronics power module converts DC energy of the DC battery to at least one of an alternating current (AC) power and a direct current (DC) power. A wireless communication device promotes wireless communication of a battery state-of-charge (SOC) of the high voltage DC battery. A liquid cooling thermal system provides positive cooling of the electronics power module.
    Type: Grant
    Filed: March 8, 2021
    Date of Patent: September 13, 2022
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Chandra S. Namuduri, Benjamin Christian, Thomas W. Nehl, Rashmi Prasad
  • Publication number: 20220285959
    Abstract: A mobile power source apparatus includes a mobile unit having a platform structure, a frame connected to the platform structure and multiple wheels rotatably connected to the platform structure to promote moving the mobile unit. An electronics power module is connected to a DC power source defining a high voltage DC battery. The electronics power module converts DC energy of the DC battery to at least one of an alternating current (AC) power and a direct current (DC) power. A wireless communication device promotes wireless communication of a battery state-of-charge (SOC) of the high voltage DC battery. A liquid cooling thermal system provides positive cooling of the electronics power module.
    Type: Application
    Filed: March 8, 2021
    Publication date: September 8, 2022
    Inventors: Chandra S. Namuduri, Benjamin Christian, Thomas W. Nehl, Rashmi Prasad