Patents by Inventor Jatila Ranasinghe

Jatila Ranasinghe 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: 20090090111
    Abstract: A supercritical steam combined cycle system including a gas turbine; a supercritical steam turbine system including a supercritical section, a high pressure section, an intermediate pressure section and at least one low pressure section; and a supercritical steam heat recovery steam generator (HRSG) for receiving exhaust gas from the gas turbine for heating fluid from the steam turbine system. The HRSG includes a supercritical evaporator arranged to supply steam to a superheater between the supercritical evaporator and the inlet of the HRSG and a reheater receiving cold reheat steam from and returning reheated steam to the steam turbine system. The reheater includes a first section disposed downstream of and a second section disposed upstream of the supercritical evaporator along the exhaust gas flow path.
    Type: Application
    Filed: October 4, 2007
    Publication date: April 9, 2009
    Applicant: General Electric Company
    Inventors: Leroy Omar Tomlinson, Raub Warfield Smith, Jatila Ranasinghe, Seyfettin Can Gulen, Diego Fernando Rancruel
  • Publication number: 20070017207
    Abstract: A combined cycle power plant including a gas turbine, a steam turbine, and a heat recovery steam generator. The power plant also includes a feedwater heater positioned downstream of the steam turbine and a fuel moisturization system in communication with the heat recovery steam generator.
    Type: Application
    Filed: July 25, 2005
    Publication date: January 25, 2007
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Raub Smith, Jatila Ranasinghe, Can Gulen
  • Patent number: 6978620
    Abstract: A variable loading rate method of starting a plurality of gas turbines (GT1, GT2) used in a combined cycle power plant for generating electricity. A first gas turbine is started and allowed to operate at a minimum load condition. The turbine is maintained at this load level while a second gas turbine is started brought up to its minimum load condition. Start-up of a steam turbine (ST) to which the gas turbines are operationally coupled is initiated while both gas turbines are maintained at their minimum load conditions. The load on both gas turbines is then increased to a predetermined level, which is greater than their minimum load levels, once operating temperatures within the steam turbine reach predetermined levels. Subsequently, both gas turbines are loaded as function of the load on the a steam turbine at to which the gas turbines are coupled.
    Type: Grant
    Filed: February 9, 2004
    Date of Patent: December 27, 2005
    Assignee: General Electric Company
    Inventors: Gregory E. Cooper, James H. Moore, Jatila Ranasinghe
  • Publication number: 20050172633
    Abstract: A variable loading rate method of starting a plurality of gas turbines (GT1, GT2) used in a combined cycle power plant for generating electricity. A first gas turbine is started and allowed to operate at a minimum load condition. The turbine is maintained at this load level while a second gas turbine is started brought up to its minimum load condition. Start-up of a steam turbine (ST) to which the gas turbines are operationally coupled is initiated while both gas turbines are maintained at their minimum load conditions. The load on both gas turbines is then increased to a predetermined level, which is greater than their minimum load levels, once operating temperatures within the steam turbine reach predetermined levels. Subsequently, both gas turbines are loaded as function of the load on the a steam turbine at to which the gas turbines are coupled.
    Type: Application
    Filed: February 9, 2004
    Publication date: August 11, 2005
    Inventors: Gregory Cooper, James Moore, Jatila Ranasinghe
  • Patent number: 6526758
    Abstract: A land based gas turbine plant includes a turbine compressor, a turbine section, and a combustor between the compressor and the turbine section. A heat recovery boiler incorporating at least one heat exchange section is arranged to receive exhaust gas from the turbine section, the heat recovery boiler receiving water passed in heat exchange relationship with the exhaust gas to produce steam. An external compressor supplies augmenting combustion air that is mixed with the steam produced in the heat recovery boiler to produce a mixture of steam and air that is injected into the combustor.
    Type: Grant
    Filed: April 17, 2001
    Date of Patent: March 4, 2003
    Assignee: General Electric Company
    Inventors: Jatila Ranasinghe, Robert Russell Priestley
  • Patent number: 6502402
    Abstract: A combined cycle system includes gas and steam turbines, a saturator and a fuel gas superheater for supplying moisturized heated fuel gas to the gas turbine, a gas turbine exhaust heat recovery system for generating steam and heating water for the superheater and a saturator heater for a recycle water conduit. A constant ratio of water supplied to the fuel gas saturator to dry fuel gas supplied to the fuel gas saturator and Wobbe number is maintained by adjusting the flow of the recycle water stream. Additional properties of the moisturized fuel gas, such as temperature, moisture content, composition, and heating value, are also used to control the water recycle stream to supply consistent moisturized fuel gas to the gas turbine system.
    Type: Grant
    Filed: November 9, 2000
    Date of Patent: January 7, 2003
    Assignee: General Electric Company
    Inventors: Raub Warfield Smith, Jatila Ranasinghe, Barrett David Gardiner
  • Publication number: 20030000218
    Abstract: A combined cycle power plant system, comprising a compressor; a combustor receiving air provided by the compressor; a gas turbine for expanding gas provided by the compressor; a heat recovery steam generator (HRSG) for receiving exhaust gases from the gas turbine. The heat recovery steam generator (HRSG) receives exhaust gases from the gas turbine. The HRSG includes a low pressure (LP) section; a high pressure (HP) section for receiving exhaust gases from the gas turbine and located upstream of the LP section, each of the LP and HP sections include an evaporator section. An intermediate pressure (IP) section is located between the HP and the LP sections, the IP section includes an economizer, first and second evaporators, and a water heater disposed between the first and second evaporators. A fuel gas heater is provided for receiving heated water from the water heater.
    Type: Application
    Filed: June 29, 2001
    Publication date: January 2, 2003
    Inventor: Jatila Ranasinghe
  • Patent number: 6499303
    Abstract: A method and apparatus for power augmentation in gas turbine cycles is provided that efficiently provides at least air and preferably both steam and air injection. In an embodiment of the invention, an air injection compressor is driven with steam used for gas turbine injection prior to its injection into the gas turbine. In addition to power output, the thermodynamic efficiency is improved in simple cycle turbine power plants with the disclosed method and apparatus.
    Type: Grant
    Filed: April 18, 2001
    Date of Patent: December 31, 2002
    Assignee: General Electric Company
    Inventors: Peter Paul Polukort, Jatila Ranasinghe, Charles Michael Jones
  • Patent number: 6499302
    Abstract: A combined cycle power plant system, comprising a compressor; a combustor receiving air provided by the compressor; a gas turbine for expanding gas provided by the compressor; a heat recovery steam generator (HRSG) for receiving exhaust gases from the gas turbine. The heat recovery steam generator (HRSG) receives exhaust gases from the gas turbine. The HRSG includes a low pressure (LP) section; a high pressure (HP) section for receiving exhaust gases from the gas turbine and located upstream of the LP section, each of the LP and HP sections include an evaporator section. An intermediate pressure (IP) section is located between the HP and the LP sections, the IP section includes an economizer, first and second evaporators, and a water heater (34) disposed between the first and second evaporators. A fuel gas heater is provided for receiving heated water from the water heater.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: December 31, 2002
    Assignee: General Electric Company
    Inventor: Jatila Ranasinghe
  • Patent number: 6446440
    Abstract: A steam injection and inlet fogging system is provided for a gas turbine power plant that includes a gas turbine having a compressor, a combustor and a turbine for driving a generator. A waste heat recovery unit is arranged to receive exhaust gas from the turbine, the former having a plurality of heat exchange sections for heating water with the exhaust gas. A flash tank is arranged to receive heated water from the waste heat recovery unit for producing steam. A first stream of makeup water from a first of the plurality of heat exchange sections is flashed to the flash tank to also produce saturated steam and water at a first location in the flash tank. A second stream of water from a second of the plurality of heat exchange sections is also flashed to the flash tank to produce saturated steam and water at a second location in the flash tank.
    Type: Grant
    Filed: September 15, 2000
    Date of Patent: September 10, 2002
    Assignee: General Electric Company
    Inventors: Jatila Ranasinghe, Charles Michael Jones, Robert Russell Priestley
  • Patent number: 6412285
    Abstract: A cooled cooling air (CCA) system is provided for application with gas turbine cycles. In an embodiment of the invention, the CCA system includes a shell and tube heat exchanger in which water flow is provided inside the tube(s) and air flow is provided on the shell side. Water exiting the heat exchanger is partially evaporated. Accordingly, the resulting two phase water/steam flow is admitted to a separator where the steam and water are separated. The saturated steam is flowed to the HRSG whereas the separator water is recycled to the heat exchanger.
    Type: Grant
    Filed: June 20, 2001
    Date of Patent: July 2, 2002
    Assignee: General Electric Company
    Inventors: Jatila Ranasinghe, William George Carberg
  • Patent number: 6405521
    Abstract: A method of augmenting power in a gas turbine plant that includes a compressor, at least one combustor, a turbine component and an output shaft, comprising a) supplying air and water to a heat recovery boiler; b) providing a turbine controller that controls supply of air, steam or a mixture of air and steam to the combustor; c) storing data in the turbine controller including properties of air, steam and equations for determining properties of any mixture of air and steam; d) measuring a differential pressure of the air, steam or mixture of air and steam across a metering tube located upstream of the combustor; e) determining instantaneously the mass flow rate of the air, steam or mixture of air and steam as a function of said differential pressure and desired power output; and f) supplying the air, steam or mixture of air and steam to the combustor at the flow rate determined in step e); wherein step f) is carried out with a control valve downstream of the metering tube, the control valve operatively connect
    Type: Grant
    Filed: May 23, 2001
    Date of Patent: June 18, 2002
    Assignee: General Electric Company
    Inventors: Jatila Ranasinghe, Walter Phillip Jones
  • Patent number: 6389794
    Abstract: Fuel gas is saturated with water heated with a heat recovery steam generator heat source. The heat source is preferably a water heating section downstream of the lower pressure evaporator to provide better temperature matching between the hot and cold heat exchange streams in that portion of the heat recovery steam generator. The increased gas mass flow due to the addition of moisture results in increased power output from the gas and steam turbines. Fuel gas saturation is followed by superheating the fuel, preferably with bottom cycle heat sources, resulting in a larger thermal efficiency gain compared to current fuel heating methods. There is a gain in power output compared to no fuel heating, even when heating the fuel to above the LP steam temperature.
    Type: Grant
    Filed: April 10, 2001
    Date of Patent: May 21, 2002
    Assignee: General Electric Company
    Inventors: Jatila Ranasinghe, Raub Warfield Smith
  • Patent number: 6370880
    Abstract: Transient conditions, such as startup, shutdown, and contingencies, in gas turbine power plants are difficult to manage; oftentimes in designs employing a fuel moisturization system, such conditions require the use of backup fuel or a temporary fuel stream flare. The present invention enables the use of cold, dry fuel during startup and smoothly transitions to the use of moisturized, superheated fuel at high load without using a backup fuel. A bypass line allows fuel to enter a fuel superheater without passing through a fuel saturator. This enables the independent operation of the fuel superheater from the fuel saturator. Additionally, dry fuel is heated in the fuel superheater before moisturized fuel enters the fuel superheater. Gradually, a transition from dry fuel to moisturized fuel occurs before the gas turbine system operates at premixed combustion mode of operation.
    Type: Grant
    Filed: November 9, 2000
    Date of Patent: April 16, 2002
    Assignee: General Electric Company
    Inventors: Raub Warfield Smith, Jatila Ranasinghe, William George Carberg
  • Patent number: 6357218
    Abstract: A heat rejection system is provided in a recirculating flow line, so that the steam production rate can be controlled from no steam production to maximum steam production for the gas turbine operating condition. For maximum steam production, the heat exchanger of the heat rejection system is bypassed so all the water is directed to the heat recovery unit (HRU). When no steam production is desired, all or a majority of the water is directed to the heat exchanger such that the heat absorbed in the HRU evaporator is equal to the heat rejected by the air cooled heat exchanger. Adjusting the flow split between these two limits allows the steam production rate to vary from no production to the maximum steam production capability corresponding to the gas turbine operating point.
    Type: Grant
    Filed: June 20, 2001
    Date of Patent: March 19, 2002
    Assignee: General Electric Company
    Inventors: Jatila Ranasinghe, Charles Michael Jones, Robert Russell Priestley
  • Patent number: 6347520
    Abstract: A method is provided for implementing a thermodynamic cycle with district water heating capabilities that combines a simplified Kalina bottoming cycle with a district water heating plant. The preferred method includes pressurizing, vaporizing and superheating a mixture working fluid (e.g., H2O/NH3) using gas turbine exhaust energy in a heat recovery vapor generator, expanding the working fluid in a turbine to produce power, and then transferring the working fluid thermal energy to the district water by condensing the working fluid in a single stage condenser. The method can also include systems that efficiently use excess thermal energy only when the district water heating demand is low, e.g., during summer months.
    Type: Grant
    Filed: February 6, 2001
    Date of Patent: February 19, 2002
    Assignee: General Electric Company
    Inventors: Jatila Ranasinghe, Raub Warfield Smith, Robert William Bjorge
  • Publication number: 20010049934
    Abstract: Fuel gas is saturated with water heated with a heat recovery steam generator heat source. The heat source is preferably a water heating section downstream of the lower pressure evaporator to provide better temperature matching between the hot and cold heat exchange streams in that portion of the heat recovery steam generator. The increased gas mass flow due to the addition of moisture results in increased power output from the gas and steam turbines. Fuel gas saturation is followed by superheating the fuel, preferably with bottom cycle heat sources, resulting in a larger thermal efficiency gain compared to current fuel heating methods. There is a gain in power output compared to no fuel heating, even when heating the fuel to above the LP steam temperature.
    Type: Application
    Filed: April 10, 2001
    Publication date: December 13, 2001
    Inventors: Jatila Ranasinghe, Raub Warfield Smith
  • Publication number: 20010047649
    Abstract: A land based gas turbine plant includes a turbine compressor, a turbine section, and a combustor between the compressor and the turbine section. A heat recovery boiler incorporating at least one heat exchange section is arranged to receive exhaust gas from the turbine section, the heat recovery boiler receiving water passed in heat exchange relationship with the exhaust gas to produce steam. An external compressor supplies augmenting combustion air that is mixed with the steam produced in the heat recovery boiler to produce a mixture of steam and air that is injected into the combustor.
    Type: Application
    Filed: April 17, 2001
    Publication date: December 6, 2001
    Inventors: Jatila Ranasinghe, Robert Russell . Priestley
  • Patent number: 6216436
    Abstract: An integrated gasification combined cycle plant is combined with a Kalina bottoming cycle. High thermal energy streams 31, 69, 169 from the gasification system are provided in heat exchange relation with the two component working fluid mixture at appropriate locations along the Kalina bottoming cycle units to supplement the thermal energy from the gas turbine exhaust 28 which heats the working fluid supplied to the vapor turbines. Particularly, low temperature heat recovery fluid from the low temperature cooling section 50b of the gasification system lies in heat exchange relation 27 with the condensed working fluid from the distillation/condensation sub-system of the Kalina cycle to preheat the working fluid prior to entry into the heat recovery vapor generator 12. Heat recovery fluid from the high temperature gas cooling section 50a of the gasification system is placed in heat exchange relation 23 and 65 with the working fluid at an intermediate location along the heat recovery vapor generator 12.
    Type: Grant
    Filed: October 15, 1998
    Date of Patent: April 17, 2001
    Assignee: General Electric Co.
    Inventors: Jatila Ranasinghe, Ashok Kumar Anand, Raub Warfield Smith
  • Patent number: 6173563
    Abstract: A method for improving the overall power rating and thermodynamic efficiency of a steam and gas turbine combined cycle plant having a conventional heat recovery steam generator (“HRSG”) as part of the bottoming cycle by cooling the inlet air to the gas turbine (particularly under circumstances when the ambient inlet air temperature to the gas turbine exceeds about 60° F.) using an external chiller subsystem.
    Type: Grant
    Filed: July 13, 1998
    Date of Patent: January 16, 2001
    Assignee: General Electric Company
    Inventors: Himanshu Bachubhai Vakil, Anthony John Dean, Jatila Ranasinghe