Of Means Controlling Boiler Or Its Feed Patents (Class 60/667)
  • Patent number: 7200996
    Abstract: The invention is a system and method for smoothly starting and controlling an ORC power plant. The system comprises a cascaded closed loop control that accounts for the lack of relationship between pump speed and pressure at startup so as to control pump speed and pressure, and that smoothly transitions into a steady state regime as a stable operating condition of the system is attained. The cascaded loop receives signals corresponding to a superheat setpoint, a pressure at an evaporator exit, and a temperature at an evaporator exit, and controls the pump speed and pressure upon startup to provide smooth operation. The system and method can further comprise a feed-forward control loop to deal with conditions at start-up and when external disturbances are applied to the ORC power plant.
    Type: Grant
    Filed: May 6, 2004
    Date of Patent: April 10, 2007
    Assignee: United Technologies Corporation
    Inventors: Frederick James Cogswell, Pengju Kang
  • Patent number: 7165404
    Abstract: The invention relates to a method for optimizing a large-scale industrial facility, especially a power plant, consisting of m subassemblies (BGj), wherein j=1(1)m) and wherein the following steps are successively carried out: comparing the parameters (KGj) of all subassemblies (BG1 to BGj) with predetermined reference values (RWj); detecting the subassemblies (Bgi) with i=1(1)m, whose parameters (KG1) are worse than the reference values (RWi) and optimizing the subassemblies (BG1) whose parameters (KGi) are worse than the reference values (RW1).
    Type: Grant
    Filed: September 12, 2002
    Date of Patent: January 23, 2007
    Assignee: Alstom Technology Ltd
    Inventors: Alan Bird, Volker Schule, Manfred Gietz, Ewald Kitzmann
  • Patent number: 7159400
    Abstract: When a flow of a working medium stagnates in an expander or evaporator of a Rankine cycle apparatus including a closed working medium circulation circuit, a high pressure exceeding an allowable maximum pressure level of the expander or evaporator is produced within the closed working medium circulation circuit. In such a case, the water-phase working medium is first discharged via relief valves out of the circulation circuit, so that the pressure within the circulation circuit can be lowered. Then, once vapor within the evaporator, having been lowered in temperature and pressure, flows backward within the closed working medium circulation circuit, the vapor is also discharged via the relief valves out of the circulation circuit. In this way, the pressure within the expander or evaporator can be reliably prevented from exceeding the allowable maximum pressure level.
    Type: Grant
    Filed: September 30, 2004
    Date of Patent: January 9, 2007
    Assignee: Honda Motor Co., Ltd.
    Inventors: Toshihiro Tsutsui, Syogo Kawajiri, Makoto Uda, Hiroyoshi Taniguchi
  • Publication number: 20020116925
    Abstract: An auxiliary energy management system includes a power assist device connected to a turbocharger of a mobile power plant and operable in either electric motor or alternator modes to supply or receive rotary drive motion to or from the turbocharger, an energy storage device connected between the assist device and a main alternator of the plant and operable in either energy capture or supply modes to store electrical power or provide it to auxiliary power loads, and a control mechanism connected to the assist and storage devices and operable to convert the assist device between motor and alternator modes in response to sensing performance of the turbocharger and a diesel engine of the plant and operate the storage device in supply or capture modes.
    Type: Application
    Filed: February 28, 2001
    Publication date: August 29, 2002
    Inventors: Gregory James Hampson, Robert Dean King, Jochen Erich Kindling
  • Patent number: 5847266
    Abstract: An improvement is disclosed for a boiler leak system that (a) measures fluid input into the recovery boiler system, (b) measures fluid output from the recovery boiler system, and (c) calculates fluid leakage loss based on an average difference between the measured fluid input and output values. The improvement increases the accuracy and responsiveness of calculating and interpreting the difference between the input and output fluid flow of the boiler. One aspect of the invention is an improved method which includes (1) compensating for the effects of boiler drum swelling and shrinking; (2) using multiple time frames to calculate the average differences between input and output such that a balance is struck between a highly responsive leak indication (short time frame) and a highly accurate leak indication (longer time frame); and/or (3) indicating a leak only after a predetermined certain sequence of significant differences between input and output is reached.
    Type: Grant
    Filed: September 13, 1996
    Date of Patent: December 8, 1998
    Assignee: Union Camp Patent Holding, Inc.
    Inventor: Albert A. Nevruz
  • Patent number: 5732664
    Abstract: Apparati and methods for controlling the distribution of steam to a number of boilers, and for optimizing the performance of a steam boiler. The distribution of steam to the boilers is controlled by a master control system in communication with the boilers, steam subheaders, steam-flow sensors, a comparator module, a summer module, a main steam-supply header, and a pressure sensor in the main steam-supply header. The performance of an individual boiler is optimized by (a) maintaining a constant steam pressure in the boiler, (b) measuring the relative humidity of the air supply for fuel combustion, and (c) supplying and controlling the amount of steam to be mixed with the air supply to optimize the combustion process.
    Type: Grant
    Filed: August 30, 1996
    Date of Patent: March 31, 1998
    Inventor: Joseph W. Badeaux, Jr.
  • Patent number: 5559293
    Abstract: In a steam generator or boiler of the type having a pressure vessel having a zone in which heated water and steam can be separated, an outlet for the flow of pressurized steam and an outlet for the flow of liquid, a riser section in which fluid passes for heating therein and flow into the vessel zone, and a downcomer to receive the recirculated liquid from the vessel zone and feedwater for flow to the inlet of the riser section, the system includes feedwater control apparatus for sensing the mass flow of liquid in the downcomer, determining the liquid mass in the vessel zone, downcomer and riser section and controlling the feedwater rate in relation to such mass and the respective power conditions of the system, thereby providing better stability in the system operation. Trips and other problems caused by shrink and swell are thereby avoided and other benefits achieved.
    Type: Grant
    Filed: February 8, 1995
    Date of Patent: September 24, 1996
    Inventor: William J. Kirkpatrick
  • Patent number: 5435138
    Abstract: A method of reducing turbine inlet temperature excursions during sudden load demand reductions on a steam turbine, the turbine being coupled to a controllable source of high pressure, high temperature steam, incorporates throttling of steam within the steam source in conjunction with steam throttling at the turbine so as to apportion temperature drops between the source and turbine. In one form, the method includes the steps of sensing a sudden drop in load demand on the steam turbine, operating the steam source to reduce exit pressure of the steam at the steam source and bypassing sufficient steam around the steam turbine to reduce steam flow through the turbine by an amount commensurate with the drop in load demand.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: July 25, 1995
    Assignee: Westinghouse Electric Corp.
    Inventor: George J. Silvestri, Jr.
  • Patent number: 5419135
    Abstract: A power generation system for use in outer space includes a radiation receiver disposed for receiving energy from solar, stellar or planetary heat radiation. The radiation receiver includes at least two evaporator cells. Each of the evaporator cells has an inlet, an outlet, a passageway for a refrigerant, and is constructed of a heat absorptive and conductive material. Energy from the solar, stellar or planetary radiation is absorbed by the radiation received and transferred to the refrigerant for changing the refrigerant from a liquid to a gas. The refrigerant gas is directed to a turbine or other engine wherein the gas is expanded and energy is released in the form of rotation of a shaft. The turbine shaft may be coupled to a generator for converting the mechanical rotational energy to electrical power, or to a hydraulic or pneumatic pressure device arranged to store power by compression of a fluid or a gas.
    Type: Grant
    Filed: February 21, 1992
    Date of Patent: May 30, 1995
    Inventor: B. Ryland Wiggs
  • Patent number: 5410883
    Abstract: In a plant for which process control is made, a margin of an operation allowable limit for a process variable is variably established according to situations for each apparatus constituting the plant. In addition, allowable upper limits of operation considering a life consumption state and an operation schedule of each apparatus are established for respective apparatus on the basis of a life of the whole plant. The life of each apparatus and the life of the whole plant are controlled with a goal to expire all equipment substantially at the same time by reflecting the allowable operating conditions of the apparatus constituting the plant on the plant control. Therefore, it is possible to realize rational and useful plant operation.
    Type: Grant
    Filed: September 8, 1992
    Date of Patent: May 2, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Seiitsu Nigawara, Shigeaki Namba, Hiroshi Kohmoto
  • Patent number: 5347466
    Abstract: A system for simulating and optimizing a powerhouse, designed to furnish electrical power to a process plant, incorporates a plurality of units for simulating operation of the individual components of the powerhouse, and for calculating the cost of operation of the system as a whole, including the cost of fuel for the powerhouse components and the cost of purchased power needed to satisfy the power demand of the process plant beyond the capacity of the powerhouse. An adaptive search routine varies all of the operative parameters of the powerhouse, on a random basis, and repeats the simulation, in order to identify a combination of parameters which represents a lower cost solution. The range of random variation is reduced, as lower cost solutions are not found within a given number of repetitions, in order to identify a precise convergence on the optimum solution.
    Type: Grant
    Filed: July 15, 1991
    Date of Patent: September 13, 1994
    Assignee: The Board of Trustees of the University of Arkansas
    Inventors: Randall K. Nichols, Charles M. Thatcher
  • Patent number: 5329771
    Abstract: The present invention is directed to a method for operating a hermetic, small-size power plant in which a primary circulation is conducted in a main line connecting a high-speed machine including at least a turbine and a generator installed on a joint rotor, a vaporizer and a condenser. Fluid lubrication of bearings of the rotor during the continuing operation is effected by fluid medium passing through the condenser and along the main line of the primary circulation. The vaporizer is connected to the high-speed machine through medium flow paths defining a circulating medium circuit bypassing the condenser and at least partly bypassing the main line of the primary circulation to secure passage of circulating medium accumulated in the vaporizer for lubrication of the bearings of the rotor during stopping of the primary circulation.
    Type: Grant
    Filed: July 24, 1992
    Date of Patent: July 19, 1994
    Assignee: Oy High Speed Tech Ltd.
    Inventors: Timo Kytomaki, Olli Lindgren, Jarmo Alamaki, Jaakko Larjola
  • Patent number: 5237816
    Abstract: Control systems (or controllers) for once through, unfired steam generators (or boilers) which control a single parameter--the feedwater flow to the boiler--in accord with an energy or enthalpy balance between the hot gases supplied to the boiler and the steam generated in it. These control systems have a predictive mode of feedwater control and, optionally, an operator selectable, feedback mode to compensate for drifts in the predictive mode. Other corrections may also be made, and predictive and corrective flow splits can be provided to obtain maximum efficiency when the control system is utilized to regulate the operation of a dual pressure boiler.
    Type: Grant
    Filed: December 31, 1984
    Date of Patent: August 24, 1993
    Assignee: Solar Turbines Incorporated
    Inventors: Thomas E. Duffy, Alan H. Campbell, O. Leon Lindsey
  • Patent number: 5201180
    Abstract: A method for monitoring the operating condition of a steam turbine, to which an adjustable inlet steam quantity can be supplied and from which a variable, partially expanded steam quantity can be extracted, includes initially ascertaining a relative inlet steam quantity for an adjustable inlet steam quantity as a percentage value, and ascertaining a relative turbine power from the relative inlet steam quantity as a percentage value; and determining an applicable operating point from the relative inlet steam quantity and the relative turbine power, and subsequently displaying the applicable operating point inside a performance graph for various extraction steam quantities.
    Type: Grant
    Filed: April 15, 1992
    Date of Patent: April 13, 1993
    Inventor: Paul Girbig
  • Patent number: 5172654
    Abstract: A microprocessor-based sequencer for a multiple boiler heating system which allows the plural boilers to operate in a base load mode whereby one or more boilers can be made to operate at their optimum operating points and as the heating demand changes, a swing boiler accommodates the change, leaving the other(s) at their Preferred Load value until the swing boiler can no longer satisfy the demand change. At this point, the sequencer adjusts the base load level away from the preferred load set-point.
    Type: Grant
    Filed: February 10, 1992
    Date of Patent: December 22, 1992
    Assignee: Century Controls, Inc.
    Inventor: Leo P. Christiansen
  • Patent number: 4976108
    Abstract: A method and apparatus for controlling the operation of a steam turbine system, which system includes a source of steam under a controllable pressure, a plurality of governor valves connected between the source and the turbine first stage, each governor valve being movable between two selected positions each creating minimum steam flow throttling losses, a system control device (2) for producing a system control signal representative of the desired power level to be supplied by the turbine system, and a governor valve control (8) connected for producing a valve control signal in response to an input signal and for positioning each governor valve in accordance with the value of the valve control signal. During operation, the input signal to the governor valve control (8) is given a value which is based on the system control signal and which causes the valve control signal to have a value which will place each governor valve at least approximately at a selected position.
    Type: Grant
    Filed: May 11, 1990
    Date of Patent: December 11, 1990
    Assignee: Westinghouse Electric Corp.
    Inventors: Morton H. Binstock, Walter B. Shaltes
  • Patent number: 4969084
    Abstract: A superheater spray water control system for variable pressure applications produces an output signal representative of expected superheater absorption as a function of measured steam flow, compensates the signal for temperature variations within the superheater and adjusts it for over/under fire transients. An output signal representative of required superheater absorption from the drum to the superheater outlet, together with a spray water enthalpy signal obtained as a function of measured stem flow, is used with the compensated and adjusted actual superheater absorption and measured steam flow signals to produce a spray quantity demand signal.
    Type: Grant
    Filed: December 22, 1988
    Date of Patent: November 6, 1990
    Assignee: The Babcock & Wilcox Company
    Inventor: John W. Smith
  • Patent number: 4955200
    Abstract: A method and apparatus for improving a steam-to-steam reheat system employing the drain cooler concept in a steam turbine is disclosed. The large and complicated drain receiver of the prior art is eliminated, thereby removing a source of unreliable performance and internal flooding of MSR bundle drains. A drain cooler is utilized and its utility enhanced by installing a condensate bypass line with control valve which is used to adjust the condensing capability of the drain cooler in order to optimize the amount of scavenging steam for varying load conditions, thereby achieving an improvement in heat rate reduction.
    Type: Grant
    Filed: May 17, 1989
    Date of Patent: September 11, 1990
    Assignee: Westinghouse Electric Corp.
    Inventors: Paul W. Viscovich, George J. Silvestri, Jr.
  • Patent number: 4909037
    Abstract: A control for the fuel input to a once-through boiler connected to supply steam through a throttle valve to a turbine-generator so that the rate of energy delivery to the boiler matches the rate of energy demand on the boiler as represented by demand signal. The fuel control involves comparing a demand signal indicative of the desired energy output rate for boiler with a signal indicative of the heat released to the furnace of the boiler and controlling the fuel input rate with a proportional and integral controller so that the fuel feed rate, such as coal feeder speed, is controlled so as to bring the signals into equality. The heat release signal is obtained by first calculating a lagged value of a quantity which corresponds to boiler output, such as steam flow or turbine first stage pressure, divided by fuel feed rate, such as feeder speed. That lagged quantity is then multiplied by a quantity corresponding to the value of the fuel feed rate.
    Type: Grant
    Filed: August 31, 1989
    Date of Patent: March 20, 1990
    Assignee: General Signal Corporation
    Inventor: Robert N. Hubby
  • Patent number: 4887431
    Abstract: A method and apparatus for controlling superheater outlet temperature of a steam generator utilizes a feed-forward control signal to control a spray attemperator. The feed-forward control signal is developed as a difference between a selected flow rate for steam required by a turbine operated by the steam generator, and a measured flow rate of steam from a steam drum above the steam generator.
    Type: Grant
    Filed: April 5, 1989
    Date of Patent: December 19, 1989
    Assignee: The Babcock & Wilcox Company
    Inventor: William J. Peet
  • Patent number: 4884408
    Abstract: The production of water vapor is controlled in a plant for combusting fine-grained and dustlike solid fuels together with air in a combustion zone of a heat exchanger in the upper region of the combustion zone, a water vapor accumulator, which communicates with the heat exchanger, and a water vapor feed line leading from the water vapor accumulator to a turbine. The rate at which water vapor is produced is continually calculated and is compared with the desired value which is required by the turbine and the rates at which fuel and combustion air are supplied to the combustion zone are adjusted in accordance therewith. The combustion plant may comprise a fluidized bed cooler for cooling a part of the part of the combustion residue. That cooler may comprise a plurality of chambers provided with heat exchangers for an evaporation of feed water or for a super heating of water vapor.
    Type: Grant
    Filed: January 9, 1989
    Date of Patent: December 5, 1989
    Assignee: Metallgesellschaft Aktiengesellschaft
    Inventors: Alfred Karbach, Georg Schaub, Rolf Peters
  • Patent number: 4870823
    Abstract: In the operation of a turbine system composed of apparatus (6,12,14,16) for generating steam and a turbine first stage (4) having inlet nozzles connected to be supplied with steam from the steam generating apparatus (6,12,14,16), the steam generating apparatus (6,12,14,16) being composed of a cascade arrangement of a boiler (6) producing steam at a selected pressure which has an assigned lower limit value, a primary superheater section (12), one or more division valves (14) presenting a steam flow passage having a controllable cross-sectional area, and a secondary superheater section (16) connected between the division valves (14) and the inlet nozzles, a method for reducing the output of the system at low load levels comprising: reducing the cross-sectional area of the steam flow passage presented by the division valves (14); and increasing the rate at which heat is supplied to the steam in the secondary superheater section (16) by an amount coordinated with the reduction imparted to the cross-sectional area
    Type: Grant
    Filed: November 30, 1988
    Date of Patent: October 3, 1989
    Assignee: Westinghouse Electric Corp.
    Inventor: George J. Silvestri, Jr.
  • Patent number: 4862692
    Abstract: In order to obviate a short life and an expensive maintenance cost of boiler throttle valves as well as plant loss caused by pressure reduction at the boiler throttle valves in a supercritical pressure once-through boiler a supercritical pressure once-through boiler, in which boiler water transformed into steam in boiler furnace wall tubes is further heated in a superheater and is then fed to a main turbine, is improved in that boiler throttle valves and a heat recovery apparatus are provided on the downstream side of the boiler furnace wall tubes.
    Type: Grant
    Filed: February 26, 1988
    Date of Patent: September 5, 1989
    Assignee: Mitsubishi Jukogyo Kabushiki Kaisha
    Inventors: Seiji Fukuda, Kaneko Shozou, Takuji Fujikawa, Hiroshi Oda, Tadashi Gengo, Kazushi Fukui
  • Patent number: 4860696
    Abstract: The output vapor pressure of a boiler system is controlled by selectively starting or stopping a plurality of boiler units (#1 to #4) shiftable between a high combustion state to a low combustion state in accordance with the output vapor pressure of the entire system or by shifting the boiler units between the high and low combustion states. At least two boiler units among the plurality of boiler units are selected as adjustment units in accordance with the output vapor pressure of the entire system. Each of the adjustment units is forced to shift alternately between the high and low combustion states in accordance with the output vapor pressure while continuously holding the adjustment units in the operating state.
    Type: Grant
    Filed: October 3, 1988
    Date of Patent: August 29, 1989
    Assignee: Ebara Corporation
    Inventor: Tadao Fujita
  • Patent number: 4843824
    Abstract: A system for converting heat to kinetic energy, the system characterized by a fluid driven motor responsive to an introduction of high pressure fluid for driving a selected power train, and a pressure generator for introducing the high pressure fluid to the motor. The pressure generator includes a plurality of boiler tubes for receiving low pressure fluid, a fire box for successively transferring heat to the boiler tubes, and a pressure equalizer for incrementally equalizing pressures within the boiler tubes, whereby an introduction of low pressure fluid, followed by an efficient conversion to a high pressure fluid, is facilitated within the system.
    Type: Grant
    Filed: March 10, 1986
    Date of Patent: July 4, 1989
    Assignees: Dorothy P. Mushines, Sandra E. Banker, Gerald M. Mushines
    Inventor: Anthony Mushines
  • Patent number: 4825654
    Abstract: The steam plant is operated so that the temperature of the steam entering the water separator is compared with the saturation temperature of the steam in the separator in order to produce a temperature difference signal for control of a changeover element. When the temperature difference is less than or equal to zero, the changeover element is activated to deliver a signal corresponding to the level of water in the separator for the control of the plant. When the temperature difference signal is greater than a critical value, the changeover element is actuated to deliver a signal corresponding to the temperature of the steam downstream of the separator for the control of the plant. When the temperature difference is greater than zero and less than the critical value, the changeover element is retained in the previously activated state.
    Type: Grant
    Filed: August 11, 1988
    Date of Patent: May 2, 1989
    Assignee: Sulzer Brothers Limited
    Inventor: Cenek Svoboda
  • Patent number: 4827429
    Abstract: A method and apparatus for determining the steam temperature in the impulse chamber at the first stage exit of a multistage high pressure steam turbine utilizes measurement of steam pressure in the impulse chamber and steam pressure and temperature at the exhaust as inputs to a digital computer. The functional relationships among steam pressure, temperature, specific volume, enthalpy and entropy are stored in the computer memory, and used with these measured quantities to iteratively calculate the steam temperature at the impulse chamber.
    Type: Grant
    Filed: June 16, 1987
    Date of Patent: May 2, 1989
    Assignee: Westinghouse Electric Corp.
    Inventor: George J. Silvestri, Jr.
  • Patent number: 4747748
    Abstract: An air turbine is provided and includes a stator having a guide wheel for moist air with guide passages placed between guide blade, a rotor having a runner and inner blade passages placed between the runner blades, and an annular intermediate space between the guide blades of the stator and the runner blades of the rotor. A control unit is provided for controlling the temperature of air to be supplied to the guide wheel. Wet or moist air may expand or cool down to temperatures that are considerbly below the freezing point of water without disturbance or prevention of the operation of the turbine by formation of ice on the faces of such turbine parts as are in contact with the air flow passing through the turbine.
    Type: Grant
    Filed: February 6, 1987
    Date of Patent: May 31, 1988
    Assignee: Imatran Voima Oy
    Inventor: Per-Holger Sahlberg
  • Patent number: 4745758
    Abstract: In a plant including a multiplicity of energy conversion units which together supply load upon demand to a given process through a common junction, a system is included to economically optimize the load distribution among the multiple units dynamically during the transition of process load demand from one state to another such that when the process load supply reaches the other process demand state, the energy conversion units are substantially in their economically optimum individual load generating states.
    Type: Grant
    Filed: December 15, 1986
    Date of Patent: May 24, 1988
    Assignee: Westinghouse Electric Corp.
    Inventors: Richard E. Putman, Katherine A. Gundersen
  • Patent number: 4745757
    Abstract: A cogeneration plant is disclosed in which the feedwater from the deaerator heater is placed in heat exchange relation with the makeup water before the makeup water is delivered to the deaerator heater. The amount of heat transferred from the feedwater to the makeup water is controlled in response to the stack gas temperature. The feedwater from the heat exchanger is then placed in heat exchange relation with the stack gas, either in the economizer or through a separate coil, to take advantage of waste heat that would otherwise be lost.
    Type: Grant
    Filed: February 24, 1987
    Date of Patent: May 24, 1988
    Assignee: Energy Services Inc.
    Inventor: Soo Y. Kim
  • Patent number: 4738818
    Abstract: Excessive primary cooldown and start up of the auxiliary feedwater system in a pressurized water reactor (PWR) following a reactor trip are avoided by switching to primary coolant T.sub.avg programmed, main feedwater flow control in place of normal level programmed control. The Low T.sub.avg set point at which the main feedwater isolation valves are closed is lowered below the no load T.sub.avg temperature set point and the flow rate is decreased gradually to zero at a T.sub.avg between these two set points. In addition, the low-low level set point at which the auxiliary feedwater system is started is lowered if possible, and/or the level signal is filtered, or the start signal delayed, to increase the margin to the low-low set point.
    Type: Grant
    Filed: September 29, 1986
    Date of Patent: April 19, 1988
    Assignee: Westinghouse Electric Corp.
    Inventor: Bertrand J. Cantineau
  • Patent number: 4655691
    Abstract: A temperature-difference-actuated pump is disclosed which does not require the use of electrically operated solenoid valves or the like, making the inventive pump especially useful in locations where electricity is not readily available. Either one or two pump chambers is provided, in which is disposed a pumping element such as a flexible bag or piston. One side of each chamber is connected selectively to a boiler or condenser through a mechanically operated switch deriving its working power from the pumping element. The other side of the chamber is utilized to provide the pumping action, either directly or via a noncondensable fluid.
    Type: Grant
    Filed: August 12, 1986
    Date of Patent: April 7, 1987
    Assignee: Nippon Mining Co., Ltd.
    Inventor: Noriaki Wakao
  • Patent number: 4651530
    Abstract: A method and an apparatus for feed-water control in a steam generating plant such as a boiling water nuclear reactor having motor-driven feed-water pumps and turbine-driven feed-water pumps for supplying feed-water to a steam generator, in which the feed-water flow through the turbine-driven feed-water pumps is controlled to be maintained constant, while reducing the recirculation flow discharged from the turbine-driven feed-water pumps and fed back to the inlet thereof, so as to reduce the amount of feed-water supplied to the steam generator by the motor-driven feed-water pumps, whereby variation of water level in the steam generator during switching between the two kinds of feed-water pumps is suppressed.
    Type: Grant
    Filed: March 26, 1982
    Date of Patent: March 24, 1987
    Assignee: Hitachi, Ltd.
    Inventor: Takashi Omori
  • Patent number: 4622472
    Abstract: A hybrid power system comprises a first energy converter operating on a closed Rankine cycle and including a vapor generator for vaporizing an organic working fluid in response to heat furnished from a heat source associated with a vapor generator, a turbo-generator responsive to vaporized working fluid for generating electrical power, and a condenser responsive to vapor exhausted from the turbo-generator for converting said vapor to a condensed liquid which is returned to the vapor generator. The system also includes a second energy converter including a thermo-electric generator having a junction, a heat source for heating said junction whereby said thermo-electric generator generates electrical power, and a heat pipe for conveying heat from said last mentioned heat source to the vapor generator of the first energy converter and to the junction.
    Type: Grant
    Filed: July 16, 1984
    Date of Patent: November 11, 1986
    Assignee: Ormat Turbines Ltd.
    Inventor: Lucien Y. Bronicki
  • Patent number: 4612621
    Abstract: A system for optimizing the performance of a plurality of energy conversion devices is disclosed. Measurements of fluid flow into and out of the energy conversion devices, the efficiencies of the conversion devices and the power produced by the conversion devices are used as inputs to function blocks in a logic arrangements. The function blocks cause a decrease in load demand to be applied to the energy conversion device having the lowest efficiency and an increase in load demand to be applied to the energy conversion device having the highest efficiency.
    Type: Grant
    Filed: March 17, 1983
    Date of Patent: September 16, 1986
    Assignee: The Babcock & Wilcox Company
    Inventors: Azmi Kaya, Marion A. Keyes, IV
  • Patent number: 4601173
    Abstract: A boiler for a heat sensitive working fluid in which there are three systems, first, a stream of hot combustion gas system, second, a heat transfer fluid system and lastly, a heat sensitive working fluid system. The heat transfer fluid is at the interface between the hot combustion gas and the working fluid so as to prevent the formation of hot spots.
    Type: Grant
    Filed: April 22, 1985
    Date of Patent: July 22, 1986
    Inventor: George M. Anthony
  • Patent number: 4593528
    Abstract: A chemical energy power plant includes control of steam temperature to prevent turbine damage while allowing throttling of the power output level and rapid response to commands for changed power output level.
    Type: Grant
    Filed: September 24, 1985
    Date of Patent: June 10, 1986
    Assignee: The Garrett Corporation
    Inventor: David A. Bailey
  • Patent number: 4593527
    Abstract: In a power plant comprising an evaporator for transferring heat to the working fluid from a heat source whose temperature is subject to variation, thereby evaporating a working fluid, and a turbine driven by the evaporated working fluid, the temperature of the heat source is detected, an optimum physical value relating to the evaporation at the evaporator is caluculated in accordance with the detected temperature, and evaporation of the working fluid at the evaporator is controlled in accordance with the calculated optimum value.
    Type: Grant
    Filed: July 11, 1984
    Date of Patent: June 10, 1986
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasunobu Nakamoto, Toshiro Terayama, Mikio Takayanagi
  • Patent number: 4589255
    Abstract: The invention relates to a combined heat recovery steam generator and steam turbine. An adaptive temperature controller establishes a target temperature for controlling the boiler temperature so that the steam admitted on the boiler follows a constant enthalpy when trying to match temperature of steam and rotor temperature.
    Type: Grant
    Filed: October 25, 1984
    Date of Patent: May 20, 1986
    Assignee: Westinghouse Electric Corp.
    Inventors: Alan Martens, Gerry A. Myers
  • Patent number: 4582026
    Abstract: Disclosed is an automatic anticipatory control system for controlling, by one common control quantity, a plurality of points of operation that can be changed over individually and arbitrarily between start and stop operations and between an automatic operation mode and a manual operation mode.
    Type: Grant
    Filed: April 2, 1985
    Date of Patent: April 15, 1986
    Assignees: Hitachi, Ltd., Hitachi Engineering Co., Ltd.
    Inventors: Atsushi Takita, Akira Sugano, Masayuki Kumazaki
  • Patent number: 4576007
    Abstract: An apparatus for controlling an operation of a turbine plant on a reduction of the load on a turbine operates to compute a saturation pressure corresponding to the temperature in the downcomer pipe by using the detected values representing the conditions of the plant, and to control the reduction of the turbine to maintain the pressure in the downcomer pipe higher than the computed saturation pressure so as to prevent an occurrence of flashing.
    Type: Grant
    Filed: March 26, 1985
    Date of Patent: March 18, 1986
    Assignees: Hitachi, Ltd., Hitachi Engineering Co., Ltd.
    Inventors: Tadao Arakawa, Takeshi Ueno, Hiroshi Tsunematsu, Keiichi Toyoda, Tsuguo Hashimoto
  • Patent number: 4573323
    Abstract: Steam generating apparatus and methods wherein a liquid is recirculated within a boiler by use of a constant speed dynamic feed water pump acting both to feed the boiler and to effect recirculating therein by a jet pump with its jet nozzle in liquid flow series with the dynamic pump. The jet pump also receives water from a steam drum for recirculation through the boiler. In the event of excess feed water supply to the boiler a step-function level control for the steam drum bypasses liquid to a condenser. A second jet pump acts to utilize excess feed water to supply cool water from the condenser well under pressure to the dynamic pump so that no water is bypassed to the condenser under on-design operating conditions. For waste heat recovery to provide shaft power automatically with simplified controls.
    Type: Grant
    Filed: July 13, 1982
    Date of Patent: March 4, 1986
    Assignee: The Garrett Corporation
    Inventor: Edward A. Mock
  • Patent number: 4549503
    Abstract: A system is disclosed for increasing the main steam temperature in a boiler/turbine installation to the maximum level consistent with safe operation of the installation. The difference between the main steam temperature and a system parameter is determined and used as an index to adjust the main steam temperature set point upward or downward. The system parameter selected for comparison with the main steam temperature may be the allowable variance between the main steam temperature and the main steam temperature set point or may be a "safety margin" temperature selected so as to be below the maximum allowable temperature for the installation.
    Type: Grant
    Filed: May 14, 1984
    Date of Patent: October 29, 1985
    Assignee: The Babcock & Wilcox Company
    Inventors: Marion A. Keyes, IV, Michael P. Lukas, William H. Moss
  • Patent number: 4526006
    Abstract: A boiler for a heat sensitive working fluid in which there are three systems, first, a stream of hot combustion gas system, second, a heat transfer fluid system and lastly, a heat sensitive working fluid system. The heat transfer fluid is at the interface between the hot combustion gas and the working fluid so as to prevent the formation of hot spots.
    Type: Grant
    Filed: November 23, 1979
    Date of Patent: July 2, 1985
    Inventor: George M. Anthony
  • Patent number: 4516403
    Abstract: A feed water supply pump and a second control valve are provided in a water supply line system and a first control valve is provided at a second steam line. Further, a third control valve is provided at a hot water supply line. In this manner, the terminal temperature difference between the circulating water and the exhaust gas at the inlet and outlet of a preheating portion of an exhaust gas economizer are so controlled as to become equal. In addition, steam discharged from an exhaust outlet of a multi-pressure steam turbine is turned to water by means of a condenser and then, the condensed water is returned to a drain tank while withdrawing and collecting heat energy respectively in a lubricating oil cooler, a fresh water cooler and an air cooler of an internal combustion engine.
    Type: Grant
    Filed: April 20, 1984
    Date of Patent: May 14, 1985
    Assignee: Mitsui Engineering & Shipbuilding Co., Ltd.
    Inventor: Yoshiharu Tanaka
  • Patent number: 4510757
    Abstract: An engine which can operate satisfactorily on sources of relatively low heat, such as waste heat given off by steam generating plants, includes a heating tank operably positioned with respect to a source of heat so that fluid within the tank is heated. The fluid in the tank is selected so that its boiling point is below the temperature of the heating tank. In this way the fluid is pressurized in the tank. The pressurized fluid flows to a turbine having a hollow central shaft with hollow vanes extending radially therefrom. The pressurized fluid flowing from the ends of the vanes cause the turbine to rotate. A housing about the turbine collects the fluid expelled from the vanes. The fluid then flows through a conditioning means into a storage tank where it is then introduced back into the heating tank to be recirculated. Electronic circuitry is provided to monitor and control operation of the engine.
    Type: Grant
    Filed: January 3, 1984
    Date of Patent: April 16, 1985
    Inventor: Merrill E. Graham, Jr.
  • Patent number: 4489562
    Abstract: Fuel and oxidant feed rates into a gasifier 202 are regulated by monitoring overall output 14 and comparing with a pre-selected setpoint valve 10. An overall load demand signal 50, responsive to this comparision is generated and used as an input to control 102 oxidant feed rate. The heating value of the product gas is measured 76 and used to control 64 overall fuel feed rate to the gasifier 202. For a two stage slagging gasifier, the present invention controls 114 fuel feed rate to the slagging stage 210 responsive to the measured slagging stage reaction temperature 128.
    Type: Grant
    Filed: November 8, 1982
    Date of Patent: December 25, 1984
    Assignee: Combustion Engineering, Inc.
    Inventors: Troxell K. Snyder, Paul H. Chase
  • Patent number: 4478783
    Abstract: A system for controlling the feedwater system in a nuclear power plant is disclosed. The system utilizes a logic calculations subsystem (50) which selects the operational mode of the system to be monitored from a plurality of operational modes. A disturbance estimate calculations subsystem (52) contains a dynamic mathematic model of the feedwater system and compares measured system variables with corresponding dynamic model variables contained therein to produce signals representative of deviations therebetween. A modified feedforward calculations subsystem (54) utilizes these signals and other system parameters as inputs to a steady-state mathematical model to produce control signals to determine valve positions and pump speeds so that the control valve flows, minimum control valve pressure drop, and feedwater pump flows are at their respective demanded values.
    Type: Grant
    Filed: December 7, 1981
    Date of Patent: October 23, 1984
    Assignee: The Babcock & Wilcox Company
    Inventor: Robert P. Broadwater
  • Patent number: 4471622
    Abstract: A Rankine cycle apparatus comprises a circulating pump for circulating a working medium through the apparatus, a gas generator having a tube connected with the outlet side of the circulating pump wherein the working medium flowing in the tube is evaporated, an expander connected with the outlet side of the tube of the gas generator, a condenser having a tube connected between the outlet side of the expander and the inlet side of the circulating pump wherein the working medium flowing the tube is condensed, pressure and temperature sensors for sensing the pressure and temperature of the working medium at the outlet side of the gas generator, and a flow control valve for controlling the rate of flow of the working medium to the gas generator on the basis of the pressure and temperature sensed by the sensors.
    Type: Grant
    Filed: July 13, 1982
    Date of Patent: September 18, 1984
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventor: Eiji Kuwahara
  • Patent number: 4439687
    Abstract: There is disclosed a method and a control system for synchronizing the frequency of electrical current produced by a generator with the frequency of electrical current in an electric power grid so that the output of the generator can be provided to the grid. The generator is driven by an expansion turbine which utilizes hot pressurized gas from a process in which the pressure must be maintained constant.
    Type: Grant
    Filed: July 9, 1982
    Date of Patent: March 27, 1984
    Assignee: UOP Inc.
    Inventors: Charles E. Wood, Ronald J. Vangelisti