Patents by Inventor Ravisekhar Nadimpalli Raju

Ravisekhar Nadimpalli Raju 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: 10256732
    Abstract: A medium voltage direct current (MVDC) collector system for renewable power generation facilities includes at least one renewable energy generation device. The MVDC collector system also includes at least one direct current (DC)-to-DC (DC/DC) power converter coupled to the at least one renewable energy generation device. The at least one DC/DC power converter is configured to shift a switching operation of the DC/DC power converter between full-wave conversion and half-wave conversion. The MVDC collector system further includes at least one controller coupled to the at least one DC/DC power converter. The at least one controller is configured to regulate shifting the switching operation of the at least one DC/DC power converter between full-wave conversion and half-wave conversion.
    Type: Grant
    Filed: October 16, 2015
    Date of Patent: April 9, 2019
    Assignee: General Electric Company
    Inventors: Rui Zhou, Luis Jose Garces, Ravisekhar Nadimpalli Raju, Ashraf Said Atalla
  • Patent number: 10205399
    Abstract: Systems and methods for operating a power converter are provided. A DC to AC converter can include an inner converter and an outer converter. The inner converter can include an isolation transformer a first plurality of switching devices. The outer converter can include a second plurality of switching devices. A control method can include determining an output voltage of the outer converter. The control method can further include controlling operation of the inner converter based at least in part on the output voltage of the outer converter.
    Type: Grant
    Filed: January 13, 2017
    Date of Patent: February 12, 2019
    Assignee: GENERAL ELECTRIC COMPANY
    Inventors: Dong Dong, Robert Gregory Wagoner, Govardhan Ganireddy, Ravisekhar Nadimpalli Raju
  • Patent number: 10186995
    Abstract: Systems and methods for operating a power converter with a plurality of inverter blocks with silicon carbide MOSFETs are provided. A DC to AC converter can include a plurality of inverter blocks. Each inverter block can include a plurality of switching devices. A control method can include identifying one of a plurality of switching patterns for operation of the inverter block for each inverter block. Each switching pattern can include a plurality of switching commands. The control method can further include controlling each inverter block based on the identified switching pattern for the inverter block. The control method can further include rotating the switching patterns among the plurality of inverter blocks.
    Type: Grant
    Filed: January 13, 2017
    Date of Patent: January 22, 2019
    Assignee: GENERAL ELECTRIC COMPANY
    Inventors: Dong Dong, Robert Gregory Wagoner, Govardhan Ganireddy, Ravisekhar Nadimpalli Raju, Rui Zhou
  • Publication number: 20190006831
    Abstract: An electrical system includes a power electronics system and a bus bar coupled to the power electronic system. The power electronics system includes a switching device configured to selectively connect and disconnect. The bus bar includes a first conductive layer and a second conductive layer. The first conductive layer is disposed directly adjacent a first insulation layer, wherein the first conductive layer is configured to conduct a first polarity of electrical power to, from, or both the power electronics system. The second conductive layer is disposed directly adjacent the first insulation layer, and is configured to conduct a second polarity of electrical power opposite the first polarity to, from, or both the power electronics system. The first conductive layer comprises a first thickness half a second thickness of the second conductive layer.
    Type: Application
    Filed: September 6, 2018
    Publication date: January 3, 2019
    Inventors: Xu She, Rajib Datta, Ravisekhar Nadimpalli Raju, Maja Harfman- Todorovic, Philip Michael Cioffi
  • Publication number: 20180366270
    Abstract: A low inductance device includes a capacitor and an enclosure configured to enclose the capacitor, wherein the enclosure comprises an insulating material. The low inductance device also includes a conductive outer layer configured to surround at least a portion of an exterior surface of the enclosure.
    Type: Application
    Filed: June 15, 2017
    Publication date: December 20, 2018
    Inventor: Ravisekhar Nadimpalli Raju
  • Patent number: 10141851
    Abstract: A direct current (DC) to DC power converter includes a first converter for converting a first DC bus voltage into a first high frequency AC voltage and a second converter for converting a second high frequency alternating current (AC) voltage into a second DC bus voltage. The DC to DC converter also includes a resonant circuit for coupling the first bus converter and the second bus converter and a controller for providing switching signals to the first converter and the second converter to operate the power converter in a soft switching mode. The resonant circuit includes a high frequency transformer coupled between the first converter and the second converter and an auxiliary converter coupled in series with a first resonant inductor and the high frequency transformer. The resonant circuit further includes second inductor coupled across a first winding of the high frequency transformer. An auxiliary voltage generated by auxiliary converter is added in series with an output voltage of the first converter.
    Type: Grant
    Filed: March 25, 2016
    Date of Patent: November 27, 2018
    Assignee: GENERAL ELECTRIC COMPANY
    Inventor: Ravisekhar Nadimpalli Raju
  • Patent number: 10110149
    Abstract: Systems and methods for grounding power generation systems with silicon carbide MOSFET power converters are provided. A power generation system can include a power generator comprising a multiphase rotor configured to generate multiphase alternating current power at a first voltage and a power converter comprising one or more silicon carbide MOSFETs and an isolation transformer. The power converter can be configured to convert the multiphase alternating current power from the power generator at the first voltage to multiphase alternating current power at a second voltage. The power generation system can be electrically grounded to shunt a leakage current associated with the isolation transformer of the power converter to a ground.
    Type: Grant
    Filed: January 6, 2017
    Date of Patent: October 23, 2018
    Assignee: General Electric Company
    Inventors: Robert Gregory Wagoner, Govardhan Ganireddy, Saurabh Shukla, Ravisekhar Nadimpalli Raju, Harold Robert Schnetzka
  • Patent number: 10103534
    Abstract: An electrical system includes a power electronics system and a bus bar coupled to the power electronic system. The power electronics system includes a switching device configured to selectively connect and disconnect. The bus bar includes a first conductive layer and a second conductive layer. The first conductive layer is disposed directly adjacent a first insulation layer, wherein the first conductive layer is configured to conduct a first polarity of electrical power to, from, or both the power electronics system. The second conductive layer is disposed directly adjacent the first insulation layer, and is configured to conduct a second polarity of electrical power opposite the first polarity to, from, or both the power electronics system. The first conductive layer comprises a first thickness half a second thickness of the second conductive layer.
    Type: Grant
    Filed: October 27, 2016
    Date of Patent: October 16, 2018
    Assignee: GENERAL ELECTRIC COMPANY
    Inventors: Xu She, Rajib Datta, Ravisekhar Nadimpalli Raju, Maja Harfman-Todorovic, Philip Michael Cioffi
  • Patent number: 10103665
    Abstract: Systems and methods for protecting the redundancy of inverter blocks are provided. In one example implementation, a system can include a plurality of inverter blocks. Each inverter block can include a first conversion entity configured to convert DC power to AC power, a second conversion entity configured to convert AC power to DC power, and a third conversion entity configured to convert DC power to AC power. An isolation transformer can be coupled between the first conversion entity and the second conversion entity. The system includes an inverter block switching element coupled to an output of each inverter block. A protection element is disposed in each inverter block. The system includes one or more control devices configured to isolate at least one of the plurality of inverter blocks based at least in part on a status of the protection element disposed in the inverter block.
    Type: Grant
    Filed: January 6, 2017
    Date of Patent: October 16, 2018
    Assignee: General Electric Company
    Inventors: Robert Gregory Wagoner, Govardhan Ganireddy, Saurabh Shukla, Ravisekhar Nadimpalli Raju, Harold Robert Schnetzka
  • Publication number: 20180212512
    Abstract: Systems and methods for providing automatic short circuit protection in an electrical system via a switching device. In some embodiments, the switching device includes a switching transistor that selectively switches between an open position and a closed position based at least in part on a switching control signal, for example, to facilitate converting electrical power with first electrical characteristics output into electrical power with the second electrical characteristics.
    Type: Application
    Filed: January 20, 2017
    Publication date: July 26, 2018
    Inventors: Ravisekhar Nadimpalli Raju, Ramanujam Ramabhadran, Ljubisa Dragoljub Stevanovic, William George Earls
  • Patent number: 10033298
    Abstract: Systems and methods for providing automatic short circuit protection in an electrical system via a switching device. In some embodiments, the switching device includes a switching transistor that selectively switches between an open position and a closed position based at least in part on a switching control signal, for example, to facilitate converting electrical power with first electrical characteristics output into electrical power with the second electrical characteristics.
    Type: Grant
    Filed: January 20, 2017
    Date of Patent: July 24, 2018
    Assignee: GENERAL ELECTRIC COMPANY
    Inventors: Ravisekhar Nadimpalli Raju, Ramanujam Ramabhadran, Ljubisa Dragoljub Stevanovic, William George Earls
  • Publication number: 20180205334
    Abstract: Systems and methods for operating a power converter with a plurality of inverter blocks with silicon carbide MOSFETs are provided. A DC to AC converter can include a plurality of inverter blocks. Each inverter block can include a plurality of switching devices. A control method can include identifying one of a plurality of switching patterns for operation of the inverter block for each inverter block. Each switching pattern can include a plurality of switching commands. The control method can further include controlling each inverter block based on the identified switching pattern for the inverter block. The control method can further include rotating the switching patterns among the plurality of inverter blocks.
    Type: Application
    Filed: January 13, 2017
    Publication date: July 19, 2018
    Inventors: Dong Dong, Robert Gregory Wagoner, Govardhan Ganireddy, Ravisekhar Nadimpalli Raju, Rui Zhou
  • Publication number: 20180205335
    Abstract: Systems and methods for operating a power converter are provided. A DC to AC converter can include an inner converter and an outer converter. The inner converter can include an isolation transformer a first plurality of switching devices. The outer converter can include a second plurality of switching devices. A control method can include determining an output voltage of the outer converter. The control method can further include controlling operation of the inner converter based at least in part on the output voltage of the outer converter.
    Type: Application
    Filed: January 13, 2017
    Publication date: July 19, 2018
    Inventors: Dong Dong, Robert Gregory Wagoner, Govardhan Ganireddy, Ravisekhar Nadimpalli Raju
  • Patent number: 10027240
    Abstract: Systems and methods for grounding power generation units with silicon carbide MOSFET power converters are provided. A power generation unit can include a power generator configured to generate multiphase alternating current power at a first voltage. The power generation unit can also include a power converter configured to convert the multiphase alternating current power from the power generator at the first voltage to multiphase alternating current power at a second voltage. The power converter can include one or more silicon carbide MOSFETs and at least one heatsink configured to remove heat from the power converter. The at least one heatsink of the power converter can be electrically connected to a local ground formed by one or more components of the power generation unit.
    Type: Grant
    Filed: January 6, 2017
    Date of Patent: July 17, 2018
    Assignee: GENERAL ELECTRIC COMPANY
    Inventors: Robert Gregory Wagoner, Govardhan Ganireddy, Saurabh Shukla, Ravisekhar Nadimpalli Raju, Harold Robert Schnetzka
  • Publication number: 20180197676
    Abstract: An electrical component includes a magnetic core, an insulator, and a first winding. The insulator includes a first aperture disposed about a first portion of the core and a first insulator passage extending through the insulator, encircling the first aperture. The first winding extends through the first insulator passage and conducts an electrical current.
    Type: Application
    Filed: January 10, 2017
    Publication date: July 12, 2018
    Inventors: Philip Michael Cioffi, Qin Chen, Wei Zhang, Ravisekhar Nadimpalli Raju
  • Publication number: 20180198376
    Abstract: Systems and methods for grounding power generation units with silicon carbide MOSFET power converters are provided. A power generation unit can include a power generator configured to generate multiphase alternating current power at a first voltage. The power generation unit can also include a power converter configured to convert the multiphase alternating current power from the power generator at the first voltage to multiphase alternating current power at a second voltage. The power converter can include one or more silicon carbide MOSFETs and at least one heatsink configured to remove heat from the power converter. The at least one heatsink of the power converter can be electrically connected to a local ground formed by one or more components of the power generation unit.
    Type: Application
    Filed: January 6, 2017
    Publication date: July 12, 2018
    Inventors: Robert Gregory Wagoner, Govardhan Ganireddy, Saurabh Shukla, Ravisekhar Nadimpalli Raju, Harold Robert Schnetzka
  • Publication number: 20180198392
    Abstract: Systems and methods for grounding power generation systems with silicon carbide MOSFET power converters are provided. A power generation system can include a power generator comprising a multiphase rotor configured to generate multiphase alternating current power at a first voltage and a power converter comprising one or more silicon carbide MOSFETs and an isolation transformer. The power converter can be configured to convert the multiphase alternating current power from the power generator at the first voltage to multiphase alternating current power at a second voltage. The power generation system can be electrically grounded to shunt a leakage current associated with the isolation transformer of the power converter to a ground.
    Type: Application
    Filed: January 6, 2017
    Publication date: July 12, 2018
    Inventors: Robert Gregory Wagoner, Govardhan Ganireddy, Saurabh Shukla, Ravisekhar Nadimpalli Raju, Harold Robert Schnetzka
  • Publication number: 20180197669
    Abstract: A transformer includes a ceramic housing, a primary winding disposed within the housing, a secondary winding disposed outside the winding, and a core extending through a first aperture in the housing. The housing includes a first portion and a second portion. Each of the first and second portions include a planar structure having a first housing aperture, and a plurality of sidewalls extending perpendicular to the planar structure along a plurality of edges of the planar structure. The first and second portions interface with one another when the ceramic housing is assembled such that the sidewalls of the first and second portions overlap with one another.
    Type: Application
    Filed: January 10, 2017
    Publication date: July 12, 2018
    Inventors: Philip Michael Cioffi, Qin Chen, Wei Zhang, Ravisekhar Nadimpalli Raju
  • Publication number: 20180198393
    Abstract: Systems and methods for protecting the redundancy of inverter blocks are provided. In one example implementation, a system can include a plurality of inverter blocks. Each inverter block can include a first conversion entity configured to convert DC power to AC power, a second conversion entity configured to convert AC power to DC power, and a third conversion entity configured to convert DC power to AC power. An isolation transformer can be coupled between the first conversion entity and the second conversion entity. The system includes an inverter block switching element coupled to an output of each inverter block. A protection element is disposed in each inverter block. The system includes one or more control devices configured to isolate at least one of the plurality of inverter blocks based at least in part on a status of the protection element disposed in the inverter block.
    Type: Application
    Filed: January 6, 2017
    Publication date: July 12, 2018
    Inventors: Robert Gregory Wagoner, Govardhan Ganireddy, Saurabh Shukla, Ravisekhar Nadimpalli Raju, Harold Robert Schnetzka
  • Publication number: 20180191166
    Abstract: Power converters for use in energy systems are included. For instance, an energy system can include an input power source configured to provide a low voltage direct current power. The energy system can include a power converter configured to convert the low voltage direct current power provided by the input power source to a medium voltage multiphase alternating current output power suitable for provision to an alternating current power system. The power converter can include a plurality conversion modules. Each conversion module includes a plurality of bridge circuits. Each bridge circuit includes a plurality of silicon carbide switching devices coupled in series. Each conversion module is configured to provide a single phase of the medium voltage multiphase alternating current output power on a line bus of the energy system.
    Type: Application
    Filed: January 5, 2017
    Publication date: July 5, 2018
    Inventors: Robert Gregory Wagoner, Govardhan Ganireddy, Saurabh Shukla, Rajni Kant Burra, Ravisekhar Nadimpalli Raju, Rui Zhou, Rajib Datta, John Leo Bollenbecker