Patents by Inventor Chandana GAJANAYAKE

Chandana GAJANAYAKE 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: 10725107
    Abstract: A method of classifying a stator winding fault in a brushless synchronous generator includes measuring an electrical parameter of the stator winding and classifying the fault by calculating positive or negative sequence harmonics of the parameter and comparing one or more harmonic component to a threshold.
    Type: Grant
    Filed: September 12, 2017
    Date of Patent: July 28, 2020
    Assignee: ROLLS-ROYCE plc
    Inventors: Sivakumar Nadarajan, Amit Gupta, Vaiyapuri Viswanathan, Chandana Gajanayake
  • Publication number: 20180095134
    Abstract: A method of classifying a stator winding fault in a brushless synchronous generator includes measuring an electrical parameter of the stator winding and classifying the fault by calculating positive or negative sequence harmonics of the parameter and comparing one or more harmonic component to a threshold.
    Type: Application
    Filed: September 12, 2017
    Publication date: April 5, 2018
    Applicant: ROLLS-ROYCE plc
    Inventors: Sivakumar NADARAJAN, Amit GUPTA, Vaiyapuri VISWANATHAN, Chandana GAJANAYAKE
  • Publication number: 20170170715
    Abstract: A method of controlling an inverter, in which the inverter includes a single-phase inverter arrangement having a complementary pair of power switches, including the steps of: controlling the complementary pair of power switches with a modulating signal to output an AC signal; monitoring a collector-emitter voltage of each of the pair of power switches; if the collector-emitter voltage exceeds a predetermined value, the corresponding one of the pair of power switches is judged to be in a short circuit condition; and if either one of the pair of power switches is judged to be in a short circuit condition, executing a shutdown operation to switch off the corresponding one of the pair of power switches.
    Type: Application
    Filed: November 10, 2016
    Publication date: June 15, 2017
    Applicant: ROLLS-ROYCE plc
    Inventors: Mohamed HM SATHIK, Chandana GAJANAYAKE, Sivakumar NADARAJAN, Bikramjit S. BHANGU, Amit K. GUPTA
  • Patent number: 9459320
    Abstract: A method for detecting a fault in an exciter circuit, suitable for use in a brushless generator, the exciter circuit including (a) an exciter armature winding, having a plurality of armatures, arranged to generate a multiphase AC signal, each armature of the plurality of armatures providing a respective sub-signal component of the multiphase AC signal, and (b) a rectifier circuit for receiving the sub-signals via the respective armatures, the rectifier circuit comprising a plurality of components arranged to rectify the sub-signals to provide a rectified output signal, wherein the method includes the steps of: acquiring a respective operational sub-value for a first characteristic of each of at least two of the respective sub-signals; deriving an operational value indicative of a relationship between the acquired respective operational sub-values; determining whether a fault has occurred in the exciter circuit on the basis of the derived operational value.
    Type: Grant
    Filed: December 17, 2014
    Date of Patent: October 4, 2016
    Assignee: ROLLS-ROYCE plc
    Inventors: Vaiyapuri Viswanathan, Chandana Gajanayake, Amit Gupta, Sivakumar Nadarajan
  • Publication number: 20150198668
    Abstract: A method for detecting a fault in an exciter circuit, suitable for use in a brushless generator, the exciter circuit including (a) an exciter armature winding, having a plurality of armatures, arranged to generate a multiphase AC signal, each armature of the plurality of armatures providing a respective sub-signal component of the multiphase AC signal, and (b) a rectifier circuit for receiving the sub-signals via the respective armatures, the rectifier circuit comprising a plurality of components arranged to rectify the sub-signals to provide a rectified output signal, wherein the method includes the steps of: acquiring a respective operational sub-value for a first characteristic of each of at least two of the respective sub-signals; deriving an operational value indicative of a relationship between the acquired respective operational sub-values; determining whether a fault has occurred in the exciter circuit on the basis of the derived operational value.
    Type: Application
    Filed: December 17, 2014
    Publication date: July 16, 2015
    Inventors: Vaiyapuri VISWANATHAN, Chandana GAJANAYAKE, Amit GUPTA, Sivakumar NADARAJAN