Patents by Inventor Srikanth Narasimalu

Srikanth Narasimalu 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: 20120061047
    Abstract: The present invention relates to a wind turbine nacelle having a top face with a longitudinal extension in a wind direction. The nacelle comprises a cooling device having a cooling area and extending from the first face of the nacelle, and a cover having at least one inner face and at least a front edge facing the wind direction. The cooling device is enclosed by the first face of the nacelle and the inner face of the cover and is arranged in a front distance of at least 440 mm from the front edge of the cover.
    Type: Application
    Filed: January 29, 2010
    Publication date: March 15, 2012
    Applicant: VESTAS WIND SYSTEMS A/S
    Inventors: Krishnamoorthi Sivalingam, Anand Bahuguni, Ravi Kandasamy, Srikanth Narasimalu, John K. Grevsen, Jesper Nyvad, Paul T. Tietze
  • Publication number: 20120025537
    Abstract: The present invention relates to a wind turbine nacelle comprising a front end facing a wind flow and a rear end arranged downwind from the front end; a first face with a longitudinal extension between the front end and the rear end of the nacelle, the longitudinal extension of the nacelle having a total length; a velocity boundary layer, which is created by the wind flow along the first face from the front end to the rear end, the velocity boundary layer increasing in thickness along the first face and the thickness being lowest at the front end; and a free flow cooling device extending from the first face of the nacelle, the free flow cooling device comprising a cooling area. Furthermore, the cooling area is arranged in relation to the thickness of the velocity boundary layer.
    Type: Application
    Filed: January 29, 2010
    Publication date: February 2, 2012
    Applicant: VESTAS WIND SYSTEMS A/S
    Inventors: Krishnamoorthi Sivalingam, Anand Bahuguni, Ravi Kandasamy, Srikanth Narasimalu, John K. Grevsen, Jesper Nyvad, Paul T. Tietze
  • Patent number: 8104660
    Abstract: A transducer is provided that comprises a horn having a longitudinal axis, a bonding tool attached to the horn, and an ultrasonic generator attached to the horn and spaced from the bonding tool along the longitudinal axis of the horn. A flexure is attached to the horn between the bonding tool and the ultrasonic generator for supporting the horn whereby to increase its dynamic rigidity in directions transverse to the longitudinal axis.
    Type: Grant
    Filed: May 3, 2006
    Date of Patent: January 31, 2012
    Assignee: ASM Technology Singapore Pte Ltd
    Inventors: Srikanth Narasimalu, Chee Tiong Lim, Sathish Kumar Balakrishnan
  • Publication number: 20110285129
    Abstract: According to the inventive concept, there is provided a wind turbine with at least one blade. The wind turbine comprises a first accelerometer mounted at a first radial position of the blade and being adapted to determine a first acceleration value, and a second accelerometer mounted at a second radial position of the blade different from the first radial position, and the accelerometer being adapted to determine a second acceleration value. The wind turbine further comprises a controller adapted to generate a signal based on said first and second acceleration values. There is also provided a method for monitoring a blade of a wind turbine.
    Type: Application
    Filed: October 21, 2009
    Publication date: November 24, 2011
    Applicant: VESTAS WIND SYSTEMS A/S
    Inventors: Xiao Qian Li, Ingemann Hvas Sandvad, Srikanth Narasimalu
  • Patent number: 7967550
    Abstract: The invention provides a wind turbine wind turbine with two vessels, each being interchangeably in thermal communication with a heating medium which transfers heat from a heat generating structure to the vessel, and with a cooling medium which transfers heat from the vessel to an ambient space. The vessels form a compression structure which form part of a refrigerating circuit which can circulate a working fluid between the compression structure, a condenser and an evaporator. At the evaporator, cooling effect is obtained based on evaporation of a working fluid, and the cooling can be utilized for cooling a heat generating component in the wind turbine.
    Type: Grant
    Filed: November 18, 2009
    Date of Patent: June 28, 2011
    Assignee: Vestas Wind Systems A/S
    Inventors: John K. Grevsen, Srikanth Narasimalu, Jesper Nyvad, Poul Torben Tietze, Anand Bahuguni, Krishnamoorthi Sivalingam
  • Publication number: 20110148113
    Abstract: A damper which effectively dampens vibrations experienced by a shaft in a drive train of a wind turbine generator, such as a main shaft of the WTG, is disclosed. The damper includes a vibration sensor adapted to provide a vibration signal in response to the vibrations of the shaft, an electromagnet adapted to provide an electromagnetic force to the shaft, and a controller operably coupled to the vibration sensor and the electromagnet. The controller is adapted to generate command signals to provide a suitable drive current to the electromagnet in response to the vibration signal, and the electromagnet is adapted to provide an electromagnetic force to the shaft and thereby actively dampen the vibrations of the shaft.
    Type: Application
    Filed: December 17, 2010
    Publication date: June 23, 2011
    Applicant: VESTAS WIND SYSTEMS A/S
    Inventors: Huaizhong Li, Saravana Ranganathan Damodaran, Srikanth Narasimalu
  • Patent number: 7945351
    Abstract: A method for controlling the operation of a wind turbine includes determining a first measure of a mechanical input of a component of the wind turbine, and concurrently, determining a second measure of a mechanical output of the component, determining an operating frequency response function of the component from an analysis of the relation between the first measure and the second measure, comparing the operating frequency response function with a predetermined operating frequency response function and determining a possible deviation between the two, and controlling the operation of the wind turbine so as to alter the mechanical input to the component in response to the deviation. A wind turbine that implements such a method is also disclosed.
    Type: Grant
    Filed: December 11, 2009
    Date of Patent: May 17, 2011
    Assignee: Vestas Wind Systems A/S
    Inventors: Khoon Peng Lim, Tie Ling Zhang, Pey Yen Siew, Srikanth Narasimalu
  • Patent number: 7922450
    Abstract: A wind turbine blade comprises a main blade body and trailing edge section movably connected to the main blade body, and an actuator structure internally within the blade. The actuator interconnects the trailing edge section and the main blade body, and it comprises a stack of a plurality of piezoelectric elements, so that the stack of piezoelectric elements is capable of operating as a linear actuator. The actuator structure is arranged such that it is capable of causing the trailing edge section to move or deform relative to the main blade body in response to aerodynamic loads on the blade. The actuator structure is controllable by a control system applying a voltage to the stack of piezoelectric elements in response to, e.g., detected wind or load characteristics.
    Type: Grant
    Filed: March 24, 2010
    Date of Patent: April 12, 2011
    Assignee: Vestas Wind Systems A/S
    Inventor: Srikanth Narasimalu
  • Patent number: 7901196
    Abstract: A molding apparatus comprises first and second mold chases that are configured to clamp an electronic device therebetween, and a driving mechanism which drives the first and second mold chases to apply a clamping force onto the electronic device. A pressure adjustment mechanism communicates with at least one of the mold chases and applies an additional clamping pressure onto one or more portions of the mold chase. The pressure adjustment mechanism comprises movable supports that are displaceable in directions which are substantially perpendicular to the direction of the clamping force so as to transmit and apply the said additional clamping pressure onto the mold chase, and also a plurality of piezoelectric actuators which are operative to apply displacement forces to the movable supports in their displacement directions.
    Type: Grant
    Filed: March 3, 2008
    Date of Patent: March 8, 2011
    Assignee: ASM Technology Singapore Pte Ltd
    Inventors: Srikanth Narasimalu, Sathish Kumar Balakrishnan, Ning Ying, Shu Chuen Ho
  • Publication number: 20100310372
    Abstract: A rotor blade for a wind turbine comprises a rotor blade body with a root for connecting the rotor blade to a hub of a wind turbine, a tip, a leading edge and a trailing edge. The blade has a movable part, and motion transmitting means for connecting to an actuator being placed preferably outside the blade body, and transmitting motion from the actuator to the movable part. The motion transmitting means is electrically non-conductive, whereby the risk of lightning stroke accidents is reduced.
    Type: Application
    Filed: June 8, 2010
    Publication date: December 9, 2010
    Applicant: VESTAS WIND SYSTEMS A/S
    Inventor: Srikanth Narasimalu
  • Publication number: 20100247314
    Abstract: A wind turbine blade comprises a main blade body and trailing edge section movably connected to the main blade body, and an actuator structure internally within the blade. The actuator interconnects the trailing edge section and the main blade body, and it comprises a stack of a plurality of piezoelectric elements, so that the stack of piezoelectric elements is capable of operating as a linear actuator. The actuator structure is arranged such that it is capable of causing the trailing edge section to move or deform relative to the main blade body in response to aerodynamic loads on the blade. The actuator structure is controllable by a control system applying a voltage to the stack of piezoelectric elements in response to, e.g., detected wind or load characteristics.
    Type: Application
    Filed: March 24, 2010
    Publication date: September 30, 2010
    Applicant: Vestas Wind Systems A/S
    Inventor: Srikanth Narasimalu
  • Publication number: 20100148507
    Abstract: A method for controlling the operation of a wind turbine includes determining a first measure of a mechanical input of a component of the wind turbine, and concurrently, determining a second measure of a mechanical output of the component, determining an operating frequency response function of the component from an analysis of the relation between the first measure and the second measure, comparing the operating frequency response function with a predetermined operating frequency response function and determining a possible deviation between the two, and controlling the operation of the wind turbine so as to alter the mechanical input to the component in response to the deviation. A wind turbine that implements such a method is also disclosed.
    Type: Application
    Filed: December 11, 2009
    Publication date: June 17, 2010
    Applicant: VESTAS WIND SYSTEMS A/S
    Inventors: Khoon Peng Lim, Tie Ling Zhang, Pey Yen Siew, Srikanth Narasimalu
  • Publication number: 20100150704
    Abstract: The invention provides a wind turbine wind turbine with two vessels, each being interchangeably in thermal communication with a heating medium which transfers heat from a heat generating structure to the vessel, and with a cooling medium which transfers heat from the vessel to an ambient space. The vessels form a compression structure which form part of a refrigerating circuit which can circulate a working fluid between the compression structure, a condenser and an evaporator. At the evaporator, cooling effect is obtained based on evaporation of a working fluid, and the cooling can be utilized for cooling a heat generating component in the wind turbine.
    Type: Application
    Filed: November 18, 2009
    Publication date: June 17, 2010
    Applicant: VESTAS WIND SYSTEMS A/S
    Inventors: John K. Grevsen, Srikanth Narasimalu, Jesper Nyvad, Poul Torben Tietze, Anand Bahuguni, Krishnamoorthi Sivalingam
  • Publication number: 20100143124
    Abstract: In order to prevent minor deviations from expected operation in a yawing system before they lead to larger deviations, there is in accordance with a method aspect of the invention disclosed monitoring and determining deviation from an expected operation in a yawing system of a wind turbine. The method includes inputting a rotation angle input to at least one of a plurality of yaw motors, sensing an angular output of at least one of the plurality of yaw motors, receiving the rotation angle input to the at least one of the plurality of yaw motors in a signal processor, receiving the angular output of the at least one of the plurality of yaw motors, comparing at least two of the received signals, and/or comparing a mathematical relation of two of the received signals with a reference, and hereby determining whether there is any deviation from the expected operation.
    Type: Application
    Filed: November 20, 2009
    Publication date: June 10, 2010
    Applicant: VESTAS WIND SYSTEMS A/S
    Inventors: Li Xiao Qian, Srikanth Narasimalu, Ingemann Hvas Sandvad
  • Publication number: 20100134946
    Abstract: A system, method and software for protecting wind turbines from lightning strikes, as well as a wind turbine comprising the system for lightning protection, wherein at least one lightning strike protection element of said LSP system is ionized prior to a lightning strike, thus reducing the chance of damaging unprotected part(s) of the blade(s) of the wind turbine.
    Type: Application
    Filed: November 19, 2009
    Publication date: June 3, 2010
    Applicant: VESTAS WIND SYSTEMS A/S
    Inventors: Srikanth Narasimalu, Yoshiki Haraguchi, Erwin Merijn Wouterson
  • Publication number: 20090220629
    Abstract: A molding apparatus comprises first and second mold chases that are configured to clamp an electronic device therebetween, and a driving mechanism which drives the first and second mold chases to apply a clamping force onto the electronic device. A pressure adjustment mechanism communicates with at least one of the mold chases and applies an additional clamping pressure onto one or more portions of the mold chase. The pressure adjustment mechanism comprises movable supports that are displaceable in directions which are substantially perpendicular to the direction of the clamping force so as to transmit and apply the said additional clamping pressure onto the mold chase, and also a plurality of piezoelectric actuators which are operative to apply displacement forces to the movable supports in their displacement directions.
    Type: Application
    Filed: March 3, 2008
    Publication date: September 3, 2009
    Inventors: Srikanth NARASIMALU, Sathish Kumar BALAKRISHNAN, Ning YING, Shu Chuen HO
  • Patent number: 7572675
    Abstract: A method is provided for removing excess encapsulation material from unmolded surfaces of a molded substrate including semiconductor packages by utilizing an acid solution. The method comprises the steps of mounting the substrate to a holding device with the unmolded surfaces facing an acid source for supplying an acid solution, contacting the unmolded surfaces with the acid solution for a sufficient time to remove the excess encapsulation material from the unmolded surfaces while substantially avoiding contact with molded surfaces thereof, and thereafter removing the substrate from contact with the acid solution.
    Type: Grant
    Filed: January 24, 2006
    Date of Patent: August 11, 2009
    Assignee: ASM Technology Singapore Pte Ltd.
    Inventors: Srikanth Narasimalu, Premkumar Jeromerajan
  • Patent number: 7544539
    Abstract: An apparatus and method are provided for effectively heating a first die stacked above a second die attached onto a substrate during wire bonding conducted on the first die. A gas outlet positionable adjacent to the first die is configured to project a hot gas onto bond pads of the first die for bringing the bond pads to a desired bonding temperature, thereby rapidly heating the first die for effective wire bonding.
    Type: Grant
    Filed: December 29, 2005
    Date of Patent: June 9, 2009
    Assignee: ASM Technology Singapore Pte Ltd.
    Inventors: Srikanth Narasimalu, Sathish Kumar Balakrishnan, Lin Ji
  • Patent number: 7537148
    Abstract: A bonding apparatus such as an ultrasonic transducer is provided that comprises an oscillation amplification device having a longitudinal axis and a substantially triangular cross-sectional area on a plane that is orthogonal to the longitudinal axis. An ultrasonic driver is coupled to the oscillation amplification device at a first position along the longitudinal axis and a bonding tool is mounted to the oscillation amplification device at a second position along the longitudinal axis spaced from the first position.
    Type: Grant
    Filed: October 14, 2005
    Date of Patent: May 26, 2009
    Assignee: ASM Technology Singapore Pte Ltd.
    Inventors: Srikanth Narasimalu, Sathish Kumar Balakrishnan, Chee Tiong Lim
  • Patent number: 7402778
    Abstract: An oven is provided for curing or reflowing compounds on objects, such as lead frames or other substrates. The oven comprises a heating chamber, a heating assembly mounted in thermal communication with the heating chamber to provide heat thereto, and a support assembly for supporting the object in the heating chamber for heating. The heating assembly and support assembly are configured to be movable relative to one another for controllably positioning the object at variable distances with respect to the heating assembly. Heating of the object according to a heating profile can thus be achieved by controlled heating of the object at different temperatures by positioning the object at different distances with respect to the heating assembly during the heating process although there is a single heating zone.
    Type: Grant
    Filed: April 29, 2005
    Date of Patent: July 22, 2008
    Assignee: ASM Assembly Automation Ltd.
    Inventors: Kin Yik Hung, Srikanth Narasimalu, Wei Ling Chan, Man Wai Chan, Cheuk Wah Tang, Kai Chiu Wu