Patents by Inventor Nadimpally Raju

Nadimpally 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).

  • Publication number: 20130343089
    Abstract: An electronics power system includes a plurality of substantially identical power electronic modules. Each power electronic module includes a single-phase DC/AC inverter having an output side. Each power electronic module further includes a medium/high-frequency-isolated DC/DC current-to-voltage converter having an input side. The medium/high-frequency-isolated DC/DC current-to-voltage converter drives the single-phase DC/AC inverter. Each DC/DC converter and its corresponding DC/AC inverter are connected back-to-back sharing a common DC-link. The plurality of power electronics modules is stacked together in series at the input side and in parallel or series/parallel at the output side.
    Type: Application
    Filed: June 25, 2012
    Publication date: December 26, 2013
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Ranjan Kumar Gupta, Ravisekhar Nadimpalli Raju, Rajib Datta, Mohammed Agamy
  • Publication number: 20130322142
    Abstract: An AC-DC power converter is provided. The power converter includes an electrical terminal including a positive node and a negative node. The power converter also includes a first switch coupled across the positive node and the negative node and a second switch coupled in a reverse orientation relative to the first switch and in parallel to the first switch forming a first path and a second path. The power converter further includes a first electrical storage device situated in the first path and a second electrical storage device situated in the second path.
    Type: Application
    Filed: May 31, 2012
    Publication date: December 5, 2013
    Applicant: GENERAL ELECTRIC COMPANY
    Inventor: Ravisekhar Nadimpalli Raju
  • Publication number: 20130313906
    Abstract: A load bypass switch enables continuous power to remote loads in the event of 1) failure of one or more remote loads, or 2) faults within the remote loads, within a dc power system. The bypass switch utilizes the passive components of the dc loads or inverters and therefore reduces overall component count. A black start method for the remote dc system uses the same passives present inside the loads/inverters and simultaneously uses some of the features of the bypass switch. A bypass-module-yard uses multiple bypass switches enabling continuous power to the remote loads in the event of failure of one or more power distribution cables (in-feed to the remote loads) located remotely in the dc system.
    Type: Application
    Filed: May 23, 2012
    Publication date: November 28, 2013
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Ranjan Kumar Gupta, Christof Martin Sihler, Satish Sivarama Gunturi, Stefan Schroeder, Joseph Song Manguelle, Ravisekhar Nadimpalli Raju, Rajib Datta
  • Publication number: 20130162239
    Abstract: A multi-phase electronic power transformer includes a set of primary windings, wherein each primary winding is configured to couple with an input voltage. The transformer includes a pair of primary switching devices that includes a first primary switching device coupled to a first end of each primary winding and a second primary switching device coupled to a second end of each primary winding distinct from the first end of each primary winding. The transformer includes a set of secondary windings, wherein each secondary winding is configured to inductively couple with a respective primary winding and to output a voltage. The transformer includes a pair of secondary switching devices that includes a first secondary switching device coupled to a first end of each secondary winding and a second secondary switching device coupled to a second end of each secondary winding distinct from the first end of the each secondary winding.
    Type: Application
    Filed: December 22, 2011
    Publication date: June 27, 2013
    Applicant: General Electric Company
    Inventor: Ravisekhar Nadimpalli Raju
  • Publication number: 20130051091
    Abstract: A power conversion system includes a power transformer for receiving AC power at a first voltage from an input side and for delivering AC power at a second voltage to an output side. A power converter is also included in the power conversion system wherein the power converter includes an input side converter on the input side and an output side converter on the output side coupled through a plurality of DC links. A converter controller in the power converter provides control signals to the input side converter and the output side converter for regulating an active power and a reactive power flow through the power converter. Each of the input side converters and the output side converters includes at least two power converter transformers coupled between respective power converter bridges coupled to the plurality of DC links and the input side or to the plurality of DC links and the output side.
    Type: Application
    Filed: August 29, 2011
    Publication date: February 28, 2013
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Rajib Datta, Ravisekhar Nadimpalli Raju
  • Patent number: 8379416
    Abstract: A power conversion system includes a power transformer for receiving AC power at a first voltage from an input side and for delivering AC power at a second voltage to an output side. A power converter is also included in the power conversion system wherein the power converter includes an input side converter on the input side and an output side converter on the output side coupled through a plurality of DC links. A converter controller in the power converter provides control signals to the input side converter and the output side converter for regulating an active power and a reactive power flow through the power converter. Each of the input side converters and the output side converters includes at least two power converter transformers coupled between respective power converter bridges coupled to the plurality of DC links and the input side or to the plurality of DC links and the output side.
    Type: Grant
    Filed: August 29, 2011
    Date of Patent: February 19, 2013
    Assignee: General Electric Company
    Inventors: Rajib Datta, Ravisekhar Nadimpalli Raju
  • Patent number: 8310102
    Abstract: A multilevel inverter is provided. The multilevel inverter includes a plurality of bridges, each bridge configured to receive a respective portion of an input DC power and convert the respective portion to a respective converted AC power. The multilevel inverter also includes at least one bridge controller for operating at least one of the plurality of bridges in a square waveform mode. The multilevel inverter further includes a plurality of transformers, each transformer coupled to a respective bridge and configured to increase a voltage level of the respective portion of converted AC power. The plurality of transformers further includes secondary windings coupled in series with the other secondary windings to combine the respective increased voltage level portions of the converted AC power. The multilevel inverter also includes a grid converter configured to provide output power for a power grid.
    Type: Grant
    Filed: March 30, 2011
    Date of Patent: November 13, 2012
    Assignee: General Electric Company
    Inventor: Ravisekhar Nadimpalli Raju
  • Patent number: 8208274
    Abstract: An alternating current to direct current (AC to DC) power conversion system is provided. The system includes a rectifier configured to convert an input AC voltage to an initial pulsating DC voltage. The system also includes an inverter configured to convert the initial pulsating DC voltage to a converted AC voltage. The system further includes a plurality of transformers, each transformer including a primary winding paired to a secondary winding, wherein each of the primary windings is coupled in series with the other primary windings, wherein the series coupled primary windings are coupled to the inverter to receive respective portions of the converted AC voltage. The system also includes a plurality of bridges, each bridge coupled to a respective secondary winding configured to receive a respective portion of a transformed AC voltage from the respective secondary windings, and coupled in parallel to the other bridges to provide a combined DC output voltage.
    Type: Grant
    Filed: April 28, 2011
    Date of Patent: June 26, 2012
    Assignee: General Electric Company
    Inventors: Ravisekhar Nadimpalli Raju, Luis Jose Garces, Robert Louis Steigerwald, Michael Joseph Schutten
  • Publication number: 20120092898
    Abstract: An alternating current to direct current (AC to DC) power conversion system is provided. The system includes a rectifier configured to convert an input AC voltage to an initial pulsating DC voltage. The system also includes an inverter configured to convert the initial pulsating DC voltage to a converted AC voltage. The system further includes a plurality of transformers, each transformer including a primary winding paired to a secondary winding, wherein each of the primary windings is coupled in series with the other primary windings, wherein the series coupled primary windings are coupled to the inverter to receive respective portions of the converted AC voltage. The system also includes a plurality of bridges, each bridge coupled to a respective secondary winding configured to receive a respective portion of a transformed AC voltage from the respective secondary windings, and coupled in parallel to the other bridges to provide a combined DC output voltage.
    Type: Application
    Filed: April 28, 2011
    Publication date: April 19, 2012
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Ravisekhar Nadimpalli Raju, Luis Jose Garces, Robert Louis Steigerwald, Michael Joseph Schutten
  • Publication number: 20110221195
    Abstract: A multilevel inverter is provided. The multilevel inverter includes a plurality of bridges, each bridge configured to receive a respective portion of an input DC power and convert the respective portion to a respective converted AC power. The multilevel inverter also includes at least one bridge controller for operating at least one of the plurality of bridges in a square waveform mode. The multilevel inverter further includes a plurality of transformers, each transformer coupled to a respective bridge and configured to increase a voltage level of the respective portion of converted AC power. The plurality of transformers further includes secondary windings coupled in series with the other secondary windings to combine the respective increased voltage level portions of the converted AC power. The multilevel inverter also includes a grid converter configured to provide output power for a power grid.
    Type: Application
    Filed: March 30, 2011
    Publication date: September 15, 2011
    Applicant: GENERAL ELECTRIC COMPANY
    Inventor: Ravisekhar Nadimpalli Raju
  • Patent number: 7679941
    Abstract: A power conversion system has a three-phase AC input, where each AC input phase is linked to a string of cascaded single-phase AC-DC converters placed in series with a three-phase AC-DC converter. Each single-phase AC-DC converter in one embodiment includes a silicon carbide (SiC) pulse width modulated MOSFET H-bridge that placed in series with the three-phase AC-DC converter that includes a silicon (Si) SCR bridge. The single-phase AC-DC converters and the three-phase AC-DC converter together in one embodiment include a mixed silicon-carbide (SiC) and silicon (Si) device topology.
    Type: Grant
    Filed: June 6, 2007
    Date of Patent: March 16, 2010
    Assignee: General Electric Company
    Inventors: Ravisekhar Nadimpal Raju, Richard S. Zhang, Rajib Datta, Allen Michael Ritter, Ljubisa Dragoljub Stevanovic
  • Publication number: 20100014325
    Abstract: An AC-AC Converter for an AC source which in one embodiment has a first rectifier section rectifying the AC source into a first pulsed DC link voltage signal and a high frequency modulating section coupled to the first pulsed DC link voltage signal and producing a high frequency AC voltage signal. A high frequency transformer is coupled to the high frequency AC voltage signal producing a transformed high frequency AC signal. There is a second rectifier section coupled to the transformed high frequency AC signal and producing a second pulsed DC voltage signal and an unfolder section coupled to the second pulsed DC voltage signal and producing an output AC signal.
    Type: Application
    Filed: July 15, 2008
    Publication date: January 21, 2010
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Ravisekhar Nadimpalli Raju, Richard S. Zhang, Ljubisa Dragolijub Stevanovic, Jeffrey Neal Slotnick, Robert Louis Steigerwald, Luis Jose Garces
  • Patent number: 7576443
    Abstract: A method of generating electric power includes providing at least one open-winding generator having at least one winding, wherein the at least one winding has a first terminal and a second terminal. The method also includes electrically coupling the first terminal to a first electric power electronics apparatus via a first electric bus and electrically coupling the second electric terminal to a second electric power electronics apparatus via a second electric bus. The method further includes inducing and regulating a first voltage on the first electric bus and inducing and regulating a second voltage on the second electric bus.
    Type: Grant
    Filed: December 15, 2006
    Date of Patent: August 18, 2009
    Assignee: General Electric Company
    Inventor: Ravisekhar Nadimpalli Raju
  • Publication number: 20080304300
    Abstract: A power conversion system has a three-phase AC input, where each AC input phase is linked to a string of cascaded single-phase AC-DC converters placed in series with a three-phase AC-DC converter. Each single-phase AC-DC converter in one embodiment includes a silicon carbide (SiC) pulse width modulated MOSFET H-bridge that placed in series with the three-phase AC-DC converter that includes a silicon (Si) SCR bridge. The single-phase AC-DC converters and the three-phase AC-DC converter together in one embodiment include a mixed silicon-carbide (SiC) and silicon (Si) device topology.
    Type: Application
    Filed: June 6, 2007
    Publication date: December 11, 2008
    Inventors: Ravisekhar Nadimpalli Raju, Richard S. Zhang, Rajib Datta, Allen Michael Ritter, Ljubisa Dragoljub Stevanovic
  • Patent number: 7359223
    Abstract: A power converter system for supplying an output voltage is provided. The power converter system is adapted to operate in a normal mode and a fault mode. The system comprises a plurality of bridges and a plurality of transformers. The system further comprises a plurality of dc link capacitors, each coupled across a corresponding bridge. The system also includes a controller adapted for, during the normal mode, switching each bridge with a respective normal phase shift. During the fault mode, the controller is adapted for switching each of the remaining ones of the bridges with a respective adjusted phase shift to generate the output voltage. During the fault mode, at least one of the plurality of bridges is bypassed.
    Type: Grant
    Filed: March 30, 2005
    Date of Patent: April 15, 2008
    Assignee: General Electric Company
    Inventors: Rajib Datta, Kunlun Chen, Haiqing Weng, Ravisekhar Nadimpalli Raju
  • Patent number: 7324360
    Abstract: Methods and apparatus for converting power from a power source are described. In one example embodiment, the method includes controlling multiple transformer and switchgear units coupled to a power source, and controlling multiple converter units connected in parallel. Each converter unit is coupled to a respective one of the transformer and switchgear units to form an individual thread. The transformer and switchgear unit and power converters are controlled so that the carrier waveforms for each individual thread are interleaved between each other over a carrier cycle.
    Type: Grant
    Filed: October 17, 2005
    Date of Patent: January 29, 2008
    Assignee: General Electric Company
    Inventors: Allen Michel Ritter, Richard S. Zhang, Luis Jose Garces, Rajib Datta, Ravisekhar Nadimpalli Raju, Mark E. Shepard
  • Publication number: 20060166968
    Abstract: Crystalline form F of oxcarbazepine.
    Type: Application
    Filed: July 15, 2005
    Publication date: July 27, 2006
    Inventors: Sundaram Venkataraman, Nadimpally Raju, Koilkonda Purandhar, Bairy Reddy, Lekkala Reddy, Golla Mala Kondaiah
  • Publication number: 20050182113
    Abstract: The present invention relates to a process for preparing diaryl-substituted isoxazole using compounds of Formula (V) and Formula (VII): where Y is and to processes for preparing valdecoxib and parecoxib.
    Type: Application
    Filed: December 29, 2004
    Publication date: August 18, 2005
    Inventors: Venkataraman Sundaram, Anuradha Bhimireddy, Sajja Eswaraiah, Gilla Goverdhan, Koilkonda Purandhar, Surasani Rajendra, Nadimpally Raju, Anumula Reddy, Lekkala Reddy, Emani Reddy, Padi Reddy, Alla Sampath, Vecha Sravanthi