Patents by Inventor Subbarao Varigonda

Subbarao Varigonda 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: 20250192601
    Abstract: A mild-hybrid energy storage system architecture is provided, comprising: a battery; an ultracapacitor connected in parallel with the battery; a passive battery pre-charge circuit connected between a terminal of the battery and a DC bus; a battery main contactor connected in parallel with the battery pre-charge circuit between the terminal of the battery and the DC bus; a passive ultracapacitor pre-charge circuit connected between a terminal of the ultracapacitor and the DC bus; an ultracapacitor main contactor connected in parallel with the ultracapacitor pre-charge circuit between the terminal of the ultracapacitor and the DC bus; and a control module configured to independently control operation of the battery pre-charge circuit, the battery main contactor, the ultracapacitor pre-charge circuit and the ultracapacitor main contactor.
    Type: Application
    Filed: January 28, 2025
    Publication date: June 12, 2025
    Inventors: Subbarao Varigonda, Jaroslaw Leonarski, Harsha R. Ademane
  • Publication number: 20250162420
    Abstract: A system for managing power supplied to a Transportation Refrigeration Unit (TRU), includes a power supply system, at least one electric power converter, and control circuitry coupled to the power supply system and the TRU. The power supply system includes a battery unit and a fuel cell connected in parallel. The control circuitry is configured to receive information associated with an operational characteristic of a subcomponent of the TRU and predict an increase or a decrease in a load associated with the subcomponent of the TRU based on the received information. Consequently, the control circuitry broadcasts a control signal to the fuel cell at a predefined time duration before the predicted increase or decrease in the load such that the control signal regulates the power supply from the fuel cell to the subcomponent.
    Type: Application
    Filed: November 10, 2024
    Publication date: May 22, 2025
    Inventors: Vaibhav Shah, Satyanjay Sahoo, Venkata Satya Sai Ramesh Kumar Junnuri, Liujia Dong, Subbarao Varigonda
  • Publication number: 20250112491
    Abstract: A power system for a vehicle having a Transportation Refrigeration Unit (TRU) is disclosed. The power system comprises an energy storage unit adapted to supply power to the TRU. Further, the power system comprises an axle generator in communication with the energy storage unit and is adapted to supply power to the energy storage unit and the TRU. The power system comprises a charging system in communication with the energy storage unit, the axle generator, and the TRU. The charging system is configured to monitor a State of Charge (SoC) of the energy storage unit, and is configured to determine at least one operational characteristic associated with the vehicle. The operational characteristic is indicative of at least a speeding condition of the vehicle. The charging system is configured to control, based on the SoC and the operational characteristics, a power supply from the axle generator to the energy storage unit.
    Type: Application
    Filed: September 24, 2024
    Publication date: April 3, 2025
    Inventors: Lucas Chapeau, Bart Van Hassel, Liujia Dong, Subbarao Varigonda, Morteza Haji Bagheri
  • Patent number: 12244171
    Abstract: A mild-hybrid energy storage system architecture is provided, comprising: a battery; an ultracapacitor connected in parallel with the battery; a passive battery pre-charge circuit connected between a terminal of the battery and a DC bus; a battery main contactor connected in parallel with the battery pre-charge circuit between the terminal of the battery and the DC bus; a passive ultracapacitor pre-charge circuit connected between a terminal of the ultracapacitor and the DC bus; an ultracapacitor main contactor connected in parallel with the ultracapacitor pre-charge circuit between the terminal of the ultracapacitor and the DC bus; and a control module configured to independently control operation of the battery pre-charge circuit, the battery main contactor, the ultracapacitor pre-charge circuit and the ultracapacitor main contactor.
    Type: Grant
    Filed: February 27, 2024
    Date of Patent: March 4, 2025
    Assignee: Cummins Inc.
    Inventors: Subbarao Varigonda, Jaroslaw Leonarski, Harsha R. Ademane
  • Publication number: 20240283280
    Abstract: A mild-hybrid energy storage system architecture is provided, comprising: a battery; an ultracapacitor connected in parallel with the battery; a passive battery pre-charge circuit connected between a terminal of the battery and a DC bus; a battery main contactor connected in parallel with the battery pre-charge circuit between the terminal of the battery and the DC bus; a passive ultracapacitor pre-charge circuit connected between a terminal of the ultracapacitor and the DC bus; an ultracapacitor main contactor connected in parallel with the ultracapacitor pre-charge circuit between the terminal of the ultracapacitor and the DC bus; and a control module configured to independently control operation of the battery pre-charge circuit, the battery main contactor, the ultracapacitor pre-charge circuit and the ultracapacitor main contactor.
    Type: Application
    Filed: February 27, 2024
    Publication date: August 22, 2024
    Inventors: Subbarao Varigonda, Jaroslaw Leonarski, Harsha R. Ademane
  • Patent number: 12040460
    Abstract: The present disclosure provides a method of selectively charging or discharging a system with multiple battery packs connected in parallel when at least one of the battery packs has a significantly different voltage or states of charge (SOCs) than the other battery packs. The method includes charging or discharging the battery pack(s) with a voltage or state of charge (SOC) farthest from a target value until the voltage(s) or SOC(s) is within a range of another battery pack at which point the battery packs may be connected and charging or discharging can resume for the set of connected packs. This process is repeated until all the battery packs are at a predetermined minimum or maximum voltage or SOC threshold. The present disclosure also provides a method for selectively operating and charging at least one of a plurality of battery packs depending on the respective states of the battery packs.
    Type: Grant
    Filed: October 25, 2019
    Date of Patent: July 16, 2024
    Assignee: CUMMINS INC.
    Inventors: Martin T. Books, Pramod Suresh Magadi, Erik L. Piper, John P. O'Brien, Duane J. Szymanski, Bradford K. O. Palmer, Subbarao Varigonda, Jaroslaw Leonarski, Joseph E. Paquette, Carl A. Jones
  • Patent number: 11967854
    Abstract: A mild-hybrid energy storage system architecture is provided, comprising: a battery; an ultracapacitor connected in parallel with the battery; a passive battery pre-charge circuit connected between a terminal of the battery and a DC bus; a battery main contactor connected in parallel with the battery pre-charge circuit between the terminal of the battery and the DC bus; a passive ultracapacitor pre-charge circuit connected between a terminal of the ultracapacitor and the DC bus; an ultracapacitor main contactor connected in parallel with the ultracapacitor pre-charge circuit between the terminal of the ultracapacitor and the DC bus; and a control module configured to independently control operation of the battery pre-charge circuit, the battery main contactor, the ultracapacitor pre-charge circuit and the ultracapacitor main contactor.
    Type: Grant
    Filed: January 23, 2020
    Date of Patent: April 23, 2024
    Assignee: CUMMINS INC.
    Inventors: Subbarao Varigonda, Jaroslaw Leonarski, Harsha R. Ademane
  • Patent number: 11577581
    Abstract: A climate control system for vehicles includes an internal combustion engine that may be coupled to selectively power a first motor generator, and an air conditioning compressor that may be selectively powered by one or both of the first motor generator and a second motor generator, or by the internal combustion engine. The system may include a rechargeable battery, and a vehicle controller having a vehicle state circuit structured to determine a vehicle operating condition value and a state-of-charge value of the rechargeable battery, and a coupling determination circuit structured to provide an internal combustion engine-first motor generator coupling command in response to the vehicle operating condition value and the state-of-charge value. In response to the internal combustion engine-first motor generator coupling command being provided as coupled, the internal combustion engine may power the first motor generator.
    Type: Grant
    Filed: June 26, 2017
    Date of Patent: February 14, 2023
    Assignee: Cummins Inc.
    Inventors: Mahesh Madurai Kumar, Gary L. Parker, Subbarao Varigonda, Joseph E. Paquette, Benjamin David Padgett, William Brent Fields, Praveen Chitradurga Muralidhar, Vivek Anand Sujan, Dean Deter, David E. Smith
  • Publication number: 20220190629
    Abstract: A mild-hybrid energy storage system architecture is provided, comprising: a battery; an ultracapacitor connected in parallel with the battery; a passive battery pre-charge circuit connected between a terminal of the battery and a DC bus; a battery main contactor connected in parallel with the battery pre-charge circuit between the terminal of the battery and the DC bus; a passive ultracapacitor pre-charge circuit connected between a terminal of the ultracapacitor and the DC bus; an ultracapacitor main contactor connected in parallel with the ultracapacitor pre-charge circuit between the terminal of the ultracapacitor and the DC bus; and a control module configured to independently control operation of the battery pre-charge circuit, the battery main contactor, the ultracapacitor pre-charge circuit and the ultracapacitor main contactor.
    Type: Application
    Filed: January 23, 2020
    Publication date: June 16, 2022
    Inventors: Subbarao Varigonda, Jaroslaw Leonarski, Harsha R. Ademane
  • Publication number: 20210226267
    Abstract: The present disclosure provides a method of selectively charging or discharging a system with multiple battery packs connected in parallel when at least one of the battery packs has a significantly different voltage or states of charge (SOCs) than the other battery packs. The method includes charging or discharging the battery pack(s) with a voltage or state of charge (SOC) farthest from a target value until the voltage(s) or SOC(s) is within a range of another battery pack at which point the battery packs may be connected and charging or discharging can resume for the set of connected packs. This process is repeated until all the battery packs are at a predetermined minimum or maximum voltage or SOC threshold. The present disclosure also provides a method for selectively operating and charging at least one of a plurality of battery packs depending on the respective states of the battery packs.
    Type: Application
    Filed: October 25, 2019
    Publication date: July 22, 2021
    Inventors: Martin T. Books, Pramod Suresh Magadi, Erik. L. Piper, John P. O'Brien, Duane J. Szymanski, Bradford K.O. Palmer, Subbarao Varigonda, Jaroslaw Leonarski, Joseph E. Paquette, Carl A. Jones
  • Publication number: 20200358150
    Abstract: A system for controlling external thermal loads on at least one battery for a vehicle includes a battery enclosure configured to support the at least one battery external to the vehicle. The enclosure includes a thermally-reactive portion.
    Type: Application
    Filed: February 1, 2019
    Publication date: November 12, 2020
    Inventors: William B. Fields, Patrick Sill, Subbarao Varigonda
  • Publication number: 20200198472
    Abstract: A system and method to schedule a state of charge target of an electric vehicle includes a motor, a battery, and a controller communicatively coupled to the motor and the battery. The controller is structured to receive one or more parameters comprising a state of charge of the battery, and adjust the state of charge target based on the one or more parameters.
    Type: Application
    Filed: May 2, 2018
    Publication date: June 25, 2020
    Applicant: Cummins Inc.
    Inventors: Richard A. Booth, Subbarao Varigonda, Erik L. Piper
  • Patent number: 10300831
    Abstract: Hybrid power systems include an internal combustion engine and a motor/generator connectable with the engine. A reefer unit is configured to receive power from the motor/generator via a reefer power system that includes an export power inverter and an energy storage device.
    Type: Grant
    Filed: June 1, 2017
    Date of Patent: May 28, 2019
    Assignee: Cummins Inc.
    Inventors: Robert Dziuba, Nazar Al-Khayat, Mahesh Madurai Kumar, Gary L. Parker, Subbarao Varigonda, Jaroslaw Leonarski, Vivek A. Sujan, Bradford K. Palmer, William Brent Fields, John P. O'Brien
  • Patent number: 10000197
    Abstract: Mild hybrid powertrain controls and apparatuses, methods and systems including the same are disclosed. One exemplary embodiment is a mild-hybrid system comprising an engine, an electrical machine, power electronics, an energy storage system, and an electrical load. The system includes a controller structured to receive an electrical machine power command based upon a power allocation to the electrical machine, process the electrical machine power command with feedforward controls structured to compensate for an inaccuracy associated with the power electronics, process the electrical machine power command with proportional integral (PI) controls structured to compensate for a power loss associated with one or more electrical loads, provide a compensated machine power command based upon the processing with the feedforward controls and the processing with the PI controls, and output the compensated machine power command to control the electrical machine.
    Type: Grant
    Filed: August 10, 2016
    Date of Patent: June 19, 2018
    Assignee: Cummins Inc.
    Inventors: Vivek A. Sujan, Arun Prakash Thunga Gopal, Subbarao Varigonda, Jaroslaw Leonarski, Praveen Chitradurga Muralidhar
  • Publication number: 20170368913
    Abstract: The disclosure relates to a climate control system for use in on-highway semi-trucks and includes a rechargeable battery, an internal combustion engine which can be coupled or decoupled to a motor generator (MG), and an air conditioning compressor which can be coupled or decoupled to the MG or a second MG.
    Type: Application
    Filed: June 26, 2017
    Publication date: December 28, 2017
    Applicants: Cummins Inc., UT-BATTELLE, LLC
    Inventors: Mahesh Madurai Kumar, Gary L. Parker, Subbarao Varigonda, Joseph E. Paquette, Benjamin David Padgett, William Brent Fields, Praveen Chitradurga Muralidhar, Vivek Anand Sujan, Dean Deter, David E. Smith
  • Publication number: 20170349078
    Abstract: Hybrid power systems include an internal combustion engine and a motor/generator connectable with the engine. A reefer unit is configured to receive power from the motor/generator via a reefer power system that includes an export power inverter and an energy storage device.
    Type: Application
    Filed: June 1, 2017
    Publication date: December 7, 2017
    Inventors: Robert Dziuba, Nazar Al-Khayat, Mahesh Madurai Kumar, Gary L. Parker, Subbarao Varigonda, Jaroslaw Leonarski, Vivek A. Sujan, Bradford K. Palmer, William Brent Fields, John P. O'Brien
  • Patent number: 9680366
    Abstract: A controller (11a) of a DC/DC converter (10a) responsive to power output of a fuel cell power plant (13) operates under a control strategy which determines if fuel cell voltage exceeds a limit, and if so, provided neither fuel cell output current nor DC/DC converter output current is excessive, causes an increase in DC/DC converter duty cycle to thereby increase power demanded from the fuel cell stack. This eliminates the need for conventional voltage limiting to protect fuel cells from corrosion. Digital control loops and state machines are illustrated.
    Type: Grant
    Filed: May 21, 2012
    Date of Patent: June 13, 2017
    Assignee: Audi AG
    Inventors: Subbarao Varigonda, Daniel F. Orlowski
  • Publication number: 20170043757
    Abstract: Mild hybrid powertrain controls and apparatuses, methods and systems including the same are disclosed. One exemplary embodiment is a mild-hybrid system comprising an engine, an electrical machine, power electronics, an energy storage system, and an electrical load. The system includes a controller structured to receive an electrical machine power command based upon a power allocation to the electrical machine, process the electrical machine power command with feedforward controls structured to compensate for an inaccuracy associated with the power electronics, process the electrical machine power command with proportional integral (PI) controls structured to compensate for a power loss associated with one or more electrical loads, provide a compensated machine power command based upon the processing with the feedforward controls and the processing with the PI controls, and output the compensated machine power command to control the electrical machine.
    Type: Application
    Filed: August 10, 2016
    Publication date: February 16, 2017
    Inventors: Vivek A. Sujan, Arun Prakash Thunga Gopal, Subbarao Varigonda, Jaroslaw Leonarski, Praveen Chitradurga Muralidhar
  • Patent number: 9263979
    Abstract: A method of conducting smooth motor startup is provided and includes operating a motor in an open loop control scheme at startup, operating the motor in a closed loop sensorless control scheme at a time after startup and transitioning between the open loop control scheme and the closed loop control scheme by reducing a difference between an estimated rotor angle of the motor and a commanded ramping angle of the motor.
    Type: Grant
    Filed: July 26, 2012
    Date of Patent: February 16, 2016
    Assignee: CARRIER CORPORATION
    Inventors: Da Zhang, Thomas Gietzold, Subbarao Varigonda, Salih Baris Ozturk
  • Publication number: 20150229202
    Abstract: A controller (11a) of a DC/DC converter (10a) responsive to power output of a fuel cell power plant (13) operates under a control strategy which determines if fuel cell voltage exceeds a limit, and if so, provided neither fuel cell output current nor DC/DC converter output current is excessive, causes an increase in DC/DC converter duty cycle to thereby increase power demanded from the fuel cell stack. This eliminates the need for conventional voltage limiting to protect fuel cells from corrosion. Digital control loops and state machines are illustrated.
    Type: Application
    Filed: May 21, 2012
    Publication date: August 13, 2015
    Applicant: Ballard Power Systems, Inc.
    Inventors: Subbarao Varigonda, Daniel F. Orlowski