Including Start Up, Shut Down, Cleaning, Protective Or Maintenance Procedure Patents (Class 60/646)
  • Patent number: 4474012
    Abstract: A steam pressure rate limiter for a steam turbine system reduces the setting of a steam control valve when a rate of decrease in steam pressure is detected which exceeds a threshold value of rate of decrease. A floor on control of the steam control valve is enforced in order to maintain a predetermined amount of steam flow to the turbine thereby to provide for cooling of the turbine.
    Type: Grant
    Filed: July 13, 1983
    Date of Patent: October 2, 1984
    Assignee: General Electric Company
    Inventor: Harvey H. Chamberlain
  • Patent number: 4471618
    Abstract: Nuclear power plant, including a steam generator having a secondary circuit including a steam-energy converter with a first return line for condensate of relatively lower temperature and a second return line for condensate of relatively higher temperature, a mechanically acting filter disposed in the first return line, an electro-magnetically acting filter disposed in the second return line, and a by-pass line having a cut off element disposed therein and originating from the second return line and discharging at a location in the first return line upstream of the mechanically acting filter, and a method for the operation of the power plant.
    Type: Grant
    Filed: June 18, 1982
    Date of Patent: September 18, 1984
    Assignee: Kraftwerk Union Aktiengesellschaft
    Inventors: Herbert Tratz, Hans-Joachim Berger, Manfred Mischker
  • Patent number: 4452048
    Abstract: The load on the starting steam turbine or motor which drives the power recovery string of an FCC process is reduced on the order of 15% by increasing the specific volume of the air compressed by a fixed volume compressor in the string. The specific volume of the ambient air is increased by returning a portion of the compressed and thereby heated air to the inlet of the compressor in amounts sufficient to raise the temperature of the inlet air about 75.degree. F., or more.
    Type: Grant
    Filed: May 4, 1983
    Date of Patent: June 5, 1984
    Assignee: Elliott Turbomachinery Company, Inc.
    Inventors: Carl H. Geary, Jr., Norman A. Samurin
  • Patent number: 4448024
    Abstract: Enthalpy is recovered from hot industrial effluents by converting a working fluid into a foam in a flashing unit and using the foam to propel a turbine located within or at the output of the flashing unit. For liquid effluents the effluent itself serves as the working fluid. For gaseous effluents a liquid is heated by the gas and then the liquid is used as the working fluid. If the effluents contain undesirable levels of pollutants working fluid is cleaned before it is flashed. The specification discloses both impulse and reactive turbines which the foam can propel.
    Type: Grant
    Filed: September 18, 1981
    Date of Patent: May 15, 1984
    Inventors: Alberto E. Molini, Clarence Zener
  • Patent number: 4445180
    Abstract: An electric power plant, including a fossil fired boiler and a steam turbine, is operated by a control system including a plant unit master. The control system includes a boiler control for determining the inputs of fuel, air and water, and a turbine control for determining the position of the throttle valves introducing steam from the boiler to the turbine. The plant unit master provides a load demand reference in parallel to the boiler control and to the turbine control, whereby the turbine and the boiler are operated in a coordinated manner. Measuring means provide indications of throttle pressure, power generated by the system and turbine rotor speed. Distinct controllers, each including a controller and responsive to one of the aforementioned indications and its corresponding reference, modify the load demand reference before it is applied to the turbine control or to the boiler control.
    Type: Grant
    Filed: November 6, 1973
    Date of Patent: April 24, 1984
    Assignee: Westinghouse Electric Corp.
    Inventors: Guy E. Davis, Jack R. Smith
  • Patent number: 4437313
    Abstract: A method of and apparatus for controlling a steam turbine system for a combined cycle power plant using measured parameters to control the position of dampers regulating heat flow to steam generating equipment so as to limit thermal stresses, drum level surge and to provide load-following capabilities.
    Type: Grant
    Filed: November 9, 1981
    Date of Patent: March 20, 1984
    Assignee: General Electric Company
    Inventors: Bruce D. Taber, James B. Wagner
  • Patent number: 4437809
    Abstract: Rotor turning gears for turbines selectively engage with and disengage from rotor ring gears to provide for rotation of the turbine rotor when it would otherwise cease rotation. This is to equalize the effect of thermal stresses on the rotor as it cools down from operating temperatures. The turning gear is positioned by a movable carriage and interlock. The interlock prevents inadvertent engagement of the turning gear and rotor; inadvertent steam admission to the turbine when the turning gear is engaged and assures gear mesh oil to the turning gear during turning gear engagement.
    Type: Grant
    Filed: December 31, 1981
    Date of Patent: March 20, 1984
    Assignee: General Electric Company
    Inventor: Norman E. Nutter
  • Patent number: 4425762
    Abstract: A method and system for the temperature control of superheated steam in a power plant having a boiler coupled to a turbine, and a turbine bypass valve, wherein temperature control is achieved by regulating opening of the turbine bypass valve. To this end, process quantities indicative of the superheated steam temperature at the boiler outlet, the superheated steam pressure, the turbine inlet temperature, the turbine inner wall metal temperature, and the degree of opening of the turbine bypass valve are fed into a control system in which a mismatch temperature capable of leading steam into the turbine is calculated on the basis of such received process quantities. Then the control system outputs opening or closing operation command signals to the turbine bypass valve. The method is suitable to be carried out by means of a microprocesser.
    Type: Grant
    Filed: April 27, 1982
    Date of Patent: January 17, 1984
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Hidekazu Wakamatsu, Yoichiro Kogure
  • Patent number: 4418538
    Abstract: A self-starting, fuel fired, air heating system including a fuel burner fired vapor generator, a turbine, and a condenser connected in a closed circuit such that the vapor output from the vapor generator is conducted to the turbine and then to the condenser where it is condensed for return to the vapor generator. The turbine drives an air blower which passes air over the condenser for cooling the condenser and heating the air. Also, a condensate pump is driven by the turbine. The disclosure is particularly concerned with a method and apparatus which on start-up prevents the vapor generator's vapor output from being conducted to the turbine until a predetermined pressure differential has been achieved. However, after the vapor flow is once permitted, it cannot again be prevented until after the fuel burner has been shut off and restarted.
    Type: Grant
    Filed: December 11, 1980
    Date of Patent: December 6, 1983
    Assignee: TRD Inc.
    Inventor: Charles E. Heinrich
  • Patent number: 4418539
    Abstract: A method of controlling the start of a thermal power plant having a turbine, a boiler for generating superheated steam to drive the turbine, a fuel source for supplying fuel to the boiler, fuel supply controller for controlling the fuel supply from the fuel source to the boiler, and the like. The method includes a step for calculating a desired temperature of combustion gas in the boiler and, in addition, a step of feeding a process factor indicative of the start mode of the turbine. Hence the temperature of combustion gas in the boiler is controlled according not only to the start condition of the boiler but also to the start condition of the turbine, thus reducing the time necessary to start the thermal power plant.
    Type: Grant
    Filed: January 4, 1982
    Date of Patent: December 6, 1983
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Hidekazu Wakamatsu, Yoichiro Kogure
  • Patent number: 4391101
    Abstract: A power plant may include a steam generator and a steam turbine wherein the steam generator provides steam to the turbine for driving the turbine and exhausted steam from the turbine is condensed in the turbine condenser to be pumped back to the steam generator as feedwater. In order to maintain minimum feedwater pump flows and to provide an alternative flow path should the steam generator require less than the available feedwater flow, a recirculation loop is provided for returning a portion of the feedwater to the turbine condenser. According to the present invention, this return flow to the condenser may be used for deaeration of condensate and for the attemperation of bypass steam.
    Type: Grant
    Filed: April 1, 1981
    Date of Patent: July 5, 1983
    Assignee: General Electric Company
    Inventors: Donald E. Labbe, Mayo E. Brown, Jr.
  • Patent number: 4386498
    Abstract: A turbine system which includes a reheater upstream from a low pressure turbine which is subject to corrosive salt depositions from the steam. Conductance probes are inserted at predetermined positions within the low pressure turbine and based on the conductance signals the reheat temperature or load is varied so as to move the corrosive salt deposition zone away from a rotating blade stage of the low pressure turbine.
    Type: Grant
    Filed: October 15, 1980
    Date of Patent: June 7, 1983
    Assignee: Westinghouse Electric Corp.
    Inventors: Pang-Kai Lee, William M. Hickam, William G. Steltz
  • Patent number: 4375154
    Abstract: A self-starting, fuel-fired, air heating system including a vapor generator, a turbine, and a condenser connected in a closed circuit such that the vapor output from the vapor generator is conducted to the turbine and then to the condenser where it is condensed for return to the vapor generator. The turbine drives an air blower which passes air over the condenser for cooling the condenser. Also, a condensate pump is driven by the turbine. The disclosure is particularly concerned with the provision of heat exchanger and circuitry for cooling the condensed fluid output from the pump prior to its return to the vapor generator.
    Type: Grant
    Filed: December 11, 1980
    Date of Patent: March 1, 1983
    Inventor: John J. Primeau
  • Patent number: 4367628
    Abstract: A steam cycle for a nuclear power plant having two optional modes of operation. A once-through mode of operation uses direct feed of coolant water to an evaporator avoiding excessive chemical concentration buildup.A recirculation mode of operation uses a recirculation loop to direct a portion of flow from the evaporator back through the evaporator to effectively increase evaporator flow.
    Type: Grant
    Filed: February 27, 1981
    Date of Patent: January 11, 1983
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: James D. Mangus
  • Patent number: 4368520
    Abstract: A turbine control system which includes dual controllers having microcomputer processing circuits and capable of transmitting and receiving digital information to and from a plurality of valve position control circuits, also including their own microcomputer circuitry for controlling turbine steam admission valves. An operator's panel provides for two levels of automatic control as well as a manual backup which is communicative directly with all of the valve position control circuits. Overspeed protection control as well as fast valving is provided by redundant speed control circuits.
    Type: Grant
    Filed: September 29, 1980
    Date of Patent: January 11, 1983
    Assignee: Westinghouse Electric Corp.
    Inventors: Eddie Y. Hwang, Andras I. Szabo, Louis G. Ottobre
  • Patent number: 4363216
    Abstract: The condensate of a closed cycle power plant that uses an organic working fluid for lubricating the bearings of the turbine is cooled to a temperature below the condenser temperature by an auxiliary cooler before being supplied to the bearings. This subcooling of the lubricating liquid increases its viscosity to a value which causes the minimum thickness of the lubricating film in the bearings to be increased significantly. By increasing the minimum film thickness, the filtering demands on the lubricating condensate are reduced and the surface finish of the journals and bearings is less critical permitting the journals and bearing to be finished by standard precision grinding techniques. In a specific embodiment of the invention, a cannister housing the turbine/generator is provided with a sump for collecting liquid working fluid which is delivered to the bearings through a cooler.
    Type: Grant
    Filed: October 23, 1980
    Date of Patent: December 14, 1982
    Inventor: Lucien Bronicki
  • Patent number: 4362020
    Abstract: A Rankine cycle turbine drives an electric generator and a feed pump, all on a single shaft, and all enclosed within a hermetically sealed case. The shaft is vertically oriented with the turbine exhaust directed downward and the shaft is supported on hydrodynamic fluid film bearings using the process fluid as lubricant and coolant. The selection of process fluid, type of turbine, operating speed, system power rating, and cycle state points are uniquely coordinated to achieve high turbine efficiency at the temperature levels imposed by the recovery of waste heat from the more prevalent industrial processes.
    Type: Grant
    Filed: February 11, 1981
    Date of Patent: December 7, 1982
    Assignee: Mechanical Technology Incorporated
    Inventors: John S. Meacher, David E. Ruscitto
  • Patent number: 4357801
    Abstract: A process for removing carbon dioxide in geothermal power generating processes employing a geothermal fluid such as geothermal brine containing carbon dioxide, to improve the efficiency of geothermal power generation, comprises introducing an aqueous alkaline solution, preferably an aqueous calcium hydroxide solution, into a vapor stream obtained from the brine during power generation, to remove carbon dioxide from the stream. In the case, for example, of power generation by direct contact heat exchange between geothermal brine and a working fluid such as isobutane, where the working fluid is expanded to generate power, aqueous calcium hydroxide can be introduced into a direct contact condenser into contact with the working fluid therein to remove CO.sub.2 present in the working fluid, thereby aiding in reducing loss of working fluid from the system and aiding in reducing pump power. The aqueous alkaline, e.g.
    Type: Grant
    Filed: January 22, 1980
    Date of Patent: November 9, 1982
    Assignee: Occidental Research Corporation
    Inventor: Edward F. Wahl, III
  • Patent number: 4355515
    Abstract: A crossover conduit structure for transmitting steam from a first to a second turbine section having a conduit disposed between an exhaust portion of the first turbine section and an inlet portion of the second turbine section and a moisture removal structure situated downstream from the inlet portion axially along the conduit. The conduit's longitudinal axis is arranged generally perpendicular to the inlet portion's longitudinal axis with the moisture removal structure being disposed axially downstream from the inlet portion in the direction of the steam flow through the crossover conduit. The moisture removal structure includes a tapered transition section having first and second ends which are respectively disposed relatively adjacent and remote from the inlet portion, a pipe attached to the second end of the tapered portion, and an orifice or other means for regulating water and steam flow through the condensate pipe.
    Type: Grant
    Filed: September 3, 1980
    Date of Patent: October 26, 1982
    Assignee: Westinghouse Electric Corp.
    Inventors: Albert Cohen, Ralph D. Brown, William D. Scott
  • Patent number: 4353213
    Abstract: A side stream type condenser which has a first hot well for condensing steam exhausted from a turbine and storing the condensed water and a second hot well for storing the purified condensed water to prepare for water feed to a main system includes a partition plate for defining the two hot wells. The partition plate is formed with a weir portion so that part of the condensed water in the second hot well may overflow to keep a fixed water level. The weir portion is constructed in the shape of a labyrinth and is formed with a passage normally filled up with the condensed water, and a space in the upper part of the second hot well communicates with the upper space of the first hot well through this passage only. The condensed water in the first hot well is fed to a purifying system disposed outside, and is purified therein.
    Type: Grant
    Filed: August 11, 1980
    Date of Patent: October 12, 1982
    Assignee: Hitachi, Ltd.
    Inventors: Toyohiko Masuda, Takeshi Ueno, Yoji Nagai, Hiroshi Tsunematsu, Shozo Nakamura
  • Patent number: 4353216
    Abstract: A solution to the problem of excessive rotation loss heating in a bypass steam turbine has been provided by the introduction of a reverse flow of steam to the high-pressure section of the turbine during those operating periods in which such heating is of concern. The present invention is directed to a control system for automatically selecting either the forward or reverse steam flow regime as is most appropriate, depending on turbine and other related operating conditions. In a preferred embodiment, the control system includes means for selecting either a forward or reverse flow control signal to govern the steam admission control valves; means for controlling the reverse flow valve and having decisional logic for determining whether the reverse flow valve shall be open or closed; and means for controlling the ventilator valve and having decisional logic for determining whether the ventilator valve shall be open or closed.
    Type: Grant
    Filed: September 29, 1980
    Date of Patent: October 12, 1982
    Assignee: General Electric Company
    Inventor: Royston J. Dickenson
  • Patent number: 4320625
    Abstract: Improved method and apparatus for controlling thermal stress on component parts of a steam turbine while providing maximum loading and unloading rates during startup, shutdown, and other periods of load change. From monitored and derived quantities, a loading rate is calculated for each of a plurality of preselected turbine component parts and the lowest rate is selected for control. Simultaneously, and in concert with load change calculation and execution, the steam admission mode of the turbine is automatically directed to either the partial arc mode or the full arc mode as necessary to reduce stress as compared with a preselected and adaptive stress reference value.
    Type: Grant
    Filed: April 30, 1980
    Date of Patent: March 23, 1982
    Assignee: General Electric Company
    Inventors: Bernd A. K. Westphal, James H. Moore, Jr., Richard G. Livingston
  • Patent number: 4316362
    Abstract: A cross compound turbine apparatus and method of operating the same wherein the apparatus includes a first turbine generator having a high pressure turbine and a first low pressure turbine connected to a first generator driving shaft, with the second turbine generator having an intermediate pressure turbine connected to a second generator driving shaft. Driving steam is supplied to the high pressure turbine and a primary steam line communicates exhaust steam from the high pressure turbine to drive the intermediate pressure turbine during a steady state operation of the first and second turbine generator sections. A bypass steam line communicates steam from the system supplying driving steam to the high pressure turbine to the intermediate pressure turbine in a bypassing relationship to the high pressure turbine.
    Type: Grant
    Filed: November 26, 1979
    Date of Patent: February 23, 1982
    Assignee: Hitachi, Ltd.
    Inventors: Satoshi Ninomiya, Yasuhiro Yamachi, Katsukuni Hisano, Ryosuke Arie, Katsuto Kashiwahara, Hidesumi Kuwashima
  • Patent number: 4311013
    Abstract: In starting a steam turbine plant of a combined plant including a gas turbine plant in addition to the steam turbine plant, a condensation system is controlled in such a manner that water retained in a deaerated water tank used in the steam turbine plant is fed to a gas turbine waste heat recovery boiler at steam turbine plant start-up, and the condensate recovered from the boiler is stored in a condenser and a condensate tank. Feeding of water from the condenser to a deaerator is initiated when the deaerator functions satisfactorily by using as a heat source the water at the outlet of a fuel economizer of the boiler.
    Type: Grant
    Filed: February 26, 1980
    Date of Patent: January 19, 1982
    Assignee: Hitachi, Ltd.
    Inventors: Tetsuzo Kuribayashi, Hiroshi Tsunematsu
  • Patent number: 4309873
    Abstract: Method and apparatus to limit and control rotational loss heating such as occurs in a large steam turbine in the bypass mode of operation under no-load and low-load operating conditions. According to the invention, a portion of the high pressure bypass steam is admitted to the lower pressure sections of the turbine to provide motive fluid for driving the turbine while, simultaneously, a second portion of the high-pressure bypass steam is admitted to the high-pressure section of the turbine in a reverse-flow direction to pass backwards therethrough and limit the rotational loss heating. The two flows may be proportioned to control rotational loss heating in both the high-pressure and lower pressure sections of the turbine. A reverse-flow valve and a ventilator valve are provided for routing the reverse-flow of steam.
    Type: Grant
    Filed: December 19, 1979
    Date of Patent: January 12, 1982
    Assignee: General Electric Company
    Inventors: Kenneth W. Koran, William T. Parry
  • Patent number: 4308722
    Abstract: Pollutants are removed from a hot industrial effluent after which enthalpy is recovered from the hot effluent by converting a working fluid into a foam in a flashing unit and using the foam to propel a turbine. For liquid effluents the effluent itself serves as the working fluid. For gaseous effluents the scrubbing fluid used to remove pollutants is used as the working fluid.
    Type: Grant
    Filed: June 8, 1979
    Date of Patent: January 5, 1982
    Inventors: Alberto E. Molini, Clarence Zener
  • Patent number: 4302682
    Abstract: A power generation system and method of operation for generating electricity by utilizing temperature differences inherently present in the ocean between water near the surface and water from the ocean's depths. A pump provides relatively warm, surface ocean water to a flash evaporator where a portion of the water is flashed into steam. The steam is expanded through a subatmospheric pressure range turbine which exhausts into a condensing enclosure. The steam exhausting into the enclosure is condensed by relatively cold ocean water pumped thereinto. The turbine drives a generator and thus produces the electricity. The turbine speed and generator output are controlled by selectively introducing atmospheric air and relatively warm water into the exhausted motive steam flow. Such selective introduction into the exhausted steam flow of air and/or relatively warm water increases the absolute pressure at the turbine's exhaust end and thus reduces steam flow through the turbine.
    Type: Grant
    Filed: August 10, 1979
    Date of Patent: November 24, 1981
    Assignee: Westinghouse Electric Corp.
    Inventor: Bernard L. LaCoste
  • Patent number: 4288989
    Abstract: It is possible to extract mechanical energy from lower temperature heat sources than the flames of burning fuel by substituting driving fluids having lower boiling points than water and using an abentropic engine of the type described in my U.S. Pat. No. 4,109,470, both to condense the fluid for recycling and to obtain mechanical energy from the latent heat of the vapor. Thus, valuable energy sources now going to waste such as geothermal heat, solar heat, factory and power house smoke stack heat, and nuclear-waste heat are made to produce electricity via mechanical energy, virtually a reversal of the second law of thermodynamics, by use of an abentropic engine whose operational principle is that the latent heat of vapor is in fact potential energy which can be converted to mechanical energy during its condensation.
    Type: Grant
    Filed: March 19, 1979
    Date of Patent: September 15, 1981
    Inventor: James L. Cassidy
  • Patent number: 4287430
    Abstract: The operation of an electric power plant is controlled by generating a control signal in response to the pressure at the throttle valves, the load demand signal and the megawatt output of the power plant. During the start-up, before the pressure ramp ends, the control signal varies in accordance with the difference between the pressure at the throttle valves and the pressure required at the throttle valves to produce the load represented by the load demand signal and, after the pressure ramp ends, the control signal is varied in accordance with the difference between the load represented by the load demand signal and the megawatt output of the power plant. Integral separators are employed during start-up to separate the water from the steam and a bypass system is provided to collect the water from the separators and recirculate it. The firing rate of the furnace is controlled in accordance with the control signal.
    Type: Grant
    Filed: January 18, 1980
    Date of Patent: September 1, 1981
    Assignee: Foster Wheeler Energy Corporation
    Inventor: Paul V. Guido
  • Patent number: 4282715
    Abstract: A steam power plant includes a nuclear reactor for generating a supply of steam. The steam is conducted to a first turbine which forms a high pressure stage of the steam power plant. A second turbine which is located downstream of the first turbine forms an intermediate pressure stage. Additional turbines may be arranged so as to provide still lower pressure stages for the power plant. To prevent corrosion, hydrogen peroxide is added to the steam immediately upstream of the first turbine. Additional hydrogen peroxide may be added immediately upstream of subsequent turbines. The hydrogen peroxide is added by spraying and is preferably supplied in a concentration of 25 to 50 parts per billion of steam. Preferably, the hydrogen peroxide is in a concentration of 1% to 5% prior to spraying.
    Type: Grant
    Filed: November 13, 1978
    Date of Patent: August 11, 1981
    Inventors: Bengt Edwall, Anders Kullendorff
  • Patent number: 4282708
    Abstract: In shutting down a combined power plant, a steam turbine is first shutdown while operation of a gas turbine at high load is being continued, and the steam generated in a waste heat recovery boiler is passed on to a condenser through a bypass system bypassing the steam turbine. The gas turbine is then shutdown when this condition prevails, and gland sections of the steam turbine receive a supply of gland sealing steam which has been heated by a heater to a temperature level close to that of the steam attained while the steam turbine is in operation, thereby to maintain the temperature of the metal of the steam turbine gland sections at a desired level during the time the steam and gas turbines are shutdown. In restarting the combined plant, the gas turbine is first started and then the steam turbine is started.
    Type: Grant
    Filed: August 22, 1979
    Date of Patent: August 11, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Tetsuzo Kuribayashi, Tsuguo Hashimoto
  • Patent number: 4280060
    Abstract: A dedicated supervisory control system for a steam turbine-generator comprising a hierarchy of microcomputer subsystems interactive with a conventional analog electrohydraulic control system to provide control and monitoring capabilities during all operating phases of the turbine-generator. The separate microcomputer subsystems are programmed for coordinated interaction and communication through shared, dual-port read/write memory units and each microcomputer subsystem is programmed and configured to handle a separate group of control responsibilities in a distributed control system.
    Type: Grant
    Filed: June 9, 1980
    Date of Patent: July 21, 1981
    Assignee: General Electric Company
    Inventors: Jens Kure-Jensen, Richard S. Gordon, Charles L. Devlin, Frederick C. Krings
  • Patent number: 4277943
    Abstract: A method and apparatus for supplying superheated steam at desired temperatures and pressures to a steam turbine. First source steam from a boiler steam drum passes through a control valve to form regulated steam which is conducted through a heat exchanger where a portion of it is condensed. The partially condensed regulated steam exhausted from the heat exchanger is throttled by a throttling valve to a lower pressure to form control steam and the vapor therein is separated from the liquid. The vapor is transmitted through the heat exchanger and absorbs heat from the regulated steam also passing therethrough. Cooperative adjustment of the control valve and throttling valve permits gradual adjustment of the control steam's temperature and pressure leaving the heat exchanger. When the control valve is completely open, the temperature of the control steam leaving the heat exchanger is a maximum which cannot be increased by further manipulation of the control and throttle valves.
    Type: Grant
    Filed: October 10, 1979
    Date of Patent: July 14, 1981
    Assignee: Westinghouse Electric Corp.
    Inventors: George J. Silvestri, Jr., Krishnamurthy Kesavan
  • Patent number: 4275447
    Abstract: Method of regulation of the water level in boilers or steam generators, in which the inlet flow of feedwater is regulated in response to a deviation signal proportional to the difference between the real measured water level and a reference level, the proportionality factor being a linear function of the power level of the boiler with respect to the nominal power, modified by a non-linear function of .xi. which preserves very low values for .xi. close to zero and increases very rapidly for higher values of .xi. so that the total gain is increased for low power levels and high values of .xi. within a restricted range.
    Type: Grant
    Filed: May 11, 1979
    Date of Patent: June 23, 1981
    Assignee: Framatome
    Inventor: Pierre Ruiz
  • Patent number: 4269030
    Abstract: Fouling which occurs in the heat exchangers of a thermal energy conversion power plant causes the heat transfer between the circulating fluid and working fluid to be degraded, diminishing the efficiency of the plant. The invention provides for optimizing the net power level of the plant by perturbing the flow of circulating fluid individually to the heat exchangers to identify the direction of flow change which results in an increase in generated net power level and adjusting the flow of circulating fluid to each heat exchanger. This optimization may be carried out periodically. In another case, when temperature differential of the circulating fluid across at least one of the heat exchangers falls below a predetermined level, only the circulating fluid of the related heat exchangers need be altered to optimize the net power level generated by the plant.
    Type: Grant
    Filed: August 6, 1979
    Date of Patent: May 26, 1981
    Assignee: Westinghouse Electric Corp.
    Inventor: Robert L. Osborne
  • Patent number: 4267458
    Abstract: Steam flow and pressure conditions needed in a turbine to satisfy the speed and load demand of an electric power generating system are controlled by a programmed digital computer system during start-up, synchronization and load operation. Manual backup control is provided for the computer control. Throttle valve tests are provided under digital control and transfers are made to manual backup control if predetermined task errors occur.
    Type: Grant
    Filed: October 23, 1973
    Date of Patent: May 12, 1981
    Assignee: Westinghouse Electric Corp.
    Inventors: Robert Uram, Theodore C. Giras
  • Patent number: 4254627
    Abstract: A steam turbine plant is disclosed having at least one intermediate superheater which is connected to an outlet side of a high-pressure turbine by way of a check valve. A discharge pipe line is connected at one end through a flow-regulating unit to an outlet side of the high-pressure turbine upstream of the check valve and at the other end to a condenser of the plant. The flow-regulating unit is controlled in response to various pressure parameters sensed within the system. The discharge pipe line both improves the idling capability of the plant and reduces the time required to reach operating temperatures from a cold start.
    Type: Grant
    Filed: July 9, 1979
    Date of Patent: March 10, 1981
    Assignee: BBC Brown Boveri & Company Limited
    Inventors: Helmut Gruber, Kurt Reinhard
  • Patent number: 4241585
    Abstract: A method of operating a vapor generating system for use in a power plant having a turbine control valve means, steam turbine and condenser connected in a main flow circuit in a series flow relationship, in which fluid is passed through a vapor generator furnace section at a predetermined flow rate and a firing rate is established in the furnace section to apply heat to the fluid while controlling the pressure of the fluid as it exits from the furnace section. The turbine control valve means are fixed at a predetermined percent open. The firing rate is increased to a predetermined percent of full load firing rate until the firing rate approximately corresponds to the percentage of full load flow rate of the fluid. The fluid flow rate is then increased together with the firing rate in a manner to increase the throttle pressure of the fluid to the turbine in proportion to load demand on the turbine until the load on the turbine reaches a predetermined percentage of full load.
    Type: Grant
    Filed: April 14, 1978
    Date of Patent: December 30, 1980
    Assignee: Foster Wheeler Energy Corporation
    Inventor: Walter P. Gorzegno
  • Patent number: 4237691
    Abstract: A process of removing water-soluble impurities from the working medium of a steam power plant is disclosed. Steam is bled from a high-pressure turbine downstream of the Wilson Line region. The steam is partially condensed, so that impurities in the steam are carried by the condensate. Moisture separators are disposed in the feed lines connecting the bleed lines with various heaters and the like. The bleed steam is supplied to the various heaters to heat the boiler feedwater and the working fluid of the turbine. The drains of the moisture separator are connected to a purification tank to remove the impurities from the condensate.
    Type: Grant
    Filed: September 22, 1978
    Date of Patent: December 9, 1980
    Assignee: BBC Brown, Boveri & Company, Limited
    Inventor: Maurice Bodmer
  • Patent number: 4228359
    Abstract: The present stress in the turbine rotor is estimated at each control period, from the steam temperature and pressure at the turbine inlet. In addition, the future turbine inlet steam temperature or pressure is preestimated once every n.sub.T control cycles, for a given speed or load changing rate, making use of data concerning the changing rate of the turbine steam inlet temperature or pressure in relation with the change of the speed or load, which has been obtained by a learning of the past turbine operating condition. This future steam temperature or pressure at the turbine inlet is used as a factor for preestimating the future stress expected to be caused in the turbine rotor. The preestimation of the rotor stress is performed for a plurality of assumed speed or load changing rates. The turbine is controlled at the maximum speed increase-rate or load changing rate which would not cause the future stress preestimated over a given preestimation time to exceed a limit stress.
    Type: Grant
    Filed: July 28, 1978
    Date of Patent: October 14, 1980
    Assignee: Hitachi, Ltd.
    Inventors: Hiroshi Matsumoto, Yoshio Sato, Shigeyoshi Kawano, Yoshiyuki Nakano, Fumio Kato, Katsukuni Hisano, Katsuto Kashiwahara, Yasuhiko Otawara, Toshihiko Higashi, Yasuhiro Tennichi, Jube Matsumura, Koichiro Fukushima
  • Patent number: 4226086
    Abstract: An automatic control is provided for fast restarts of a hot power plant. Boiler fuel demand is increased to reach a target load based on measured turbine metal temperature and throttle pressure. Fine tuning of the fuel demand is performed to achieve an actual match between the turbine and steam temperatures. Turbine bypass valves are operated during boiler firing the control steam pressure to a programmed pressure setpoint. Boiler firing rate is high limited by total boiler outlet steam to avoid flow overheating and bypass valve position is low limited in accordance with steam flow and throttle pressure to avoid excessively low steam flow. Reheater controls are operated to match intermediate turbine temperature and reheat steam temperature.
    Type: Grant
    Filed: May 21, 1979
    Date of Patent: October 7, 1980
    Assignee: Westinghouse Electric Corp.
    Inventors: Morton H. Binstock, Robert C. Lehmer, Steven J. Johnson, John J. Topolosky, Thomas E. Smith
  • Patent number: 4215552
    Abstract: The invention provides a method for operating a power generating assembly which assembly comprises a steam generator and a turbine, and said method comprises controlling the quantity of heat released by the steam generator by a signal which is representative of the difference between the predicted stresses which will exist at the instant to+T on that part of the turbine which undergoes the greatest thermal stress and the maximum permissible stress on this same part at the same instant, to being the present instant and T being a period of time close to the time constant of the power production assembly.
    Type: Grant
    Filed: February 1, 1978
    Date of Patent: August 5, 1980
    Assignee: Alsthom-Atlantique
    Inventors: Gilbert Riollet, Jacques Bruneau
  • Patent number: 4204258
    Abstract: A turbine speed control system comprising a pair of concurrently operable electronic microprocessor-based controllers which are coupled together by a data link to functionally cooperate in controlling turbine acceleration primarily during start-up operations in accordance with a set of predetermined measured and calculated turbine conditions. One controller is operative to control the speed of the turbine at selected accelerations from turning gear to a predetermined speed value. This same controller monitors a plurality of temperature differences from preselected regions of the turbine and inhibits turbine acceleration in accordance with an out-of-limit temperature condition associated therewith. In addition, the one controller is further operative to selectively override the turbine speed hold initiated by an out-of-limit temperature condition, the override permitting the one controller to proceed with controlling the speed of the turbine at a desired acceleration.
    Type: Grant
    Filed: October 3, 1978
    Date of Patent: May 20, 1980
    Assignee: Westinghouse Electric Corp.
    Inventors: William E. Zitelli, Alan T. Heltsley
  • Patent number: 4191021
    Abstract: A small power plant utilizing waste heat wherein:an intermediate heat transfer medium being thermally stable and capable of lubricating bearings is interposed between a heat source and a turbine operating medium;heat of said intermediate heat transfer medium is taken off through a direct contact heat exchanger to change said turbine operating medium in phase from a liquid state to a gaseous state; anda portion of said intermediate heat transfer medium is supplied as the lubricant for the bearings of the turbine and generator.
    Type: Grant
    Filed: July 15, 1977
    Date of Patent: March 4, 1980
    Assignee: Hitachi, Ltd.
    Inventors: Shozo Nakamura, Michio Kuroda, Ryoichiro Oshima
  • Patent number: 4189924
    Abstract: A power generation system and method of operation for generating electricity by utilizing temperature differences inherently present in the ocean between water near the surface and water from the ocean's depths. A pump provides relatively warm, surface ocean water to a flash evaporator where a portion of the water is flashed into steam. The steam is expanded through a subatmospheric pressure range turbine which exhausts into a condensing enclosure. The steam exhausting into the enclosure is condensed by relatively cold ocean water pumped thereinto. The turbine drives a generator and thus produces the electricity. The turbine speed and generator output are controlled by selectively introducing atmospheric air and relatively warm water into the exhausted motive steam flow. Such selective introduction into the exhausted steam flow of air and/or relatively warm water increases the absolute pressure at the turbine's exhaust end and thus reduces steam flow through the turbine.
    Type: Grant
    Filed: June 22, 1978
    Date of Patent: February 26, 1980
    Assignee: Westinghouse Electric Corp.
    Inventor: Bernard L. LaCoste
  • Patent number: 4187146
    Abstract: Radioactive emissions by reason of primary-liquid-to-secondary-liquid leakage in the steam generator of pressurized water reactor power plants are reduced by a demineralizer in the discharge from the blowdown tank and also by transmitting blowdown venting vapor to the condenser. For major failures resulting in power blackout an auxiliary turbine is provided. This turbine is connected to be energized by vapor (steam) by-passed from the main steam line. The auxiliary turbine drives the pumps which pump the cooling water for the condenser. The steam which drives the auxiliary turbine is also discharged to the condenser. The condensed water flows back into the steam generators where it is discharged through the blowdown tank.
    Type: Grant
    Filed: October 13, 1977
    Date of Patent: February 5, 1980
    Assignee: Westinghouse Electric Corp.
    Inventors: Ti-Ke Shen, John R. Coombe
  • Patent number: 4184322
    Abstract: Sensible heat in the hot effluent gas stream leaving a partial oxidation gas generator for the production of gaseous mixtures comprising H.sub.2 +CO i.e. synthesis gas, reducing gas, or fuel gas, is used at maximum temperature to heat a stream of gaseous heat transfer fluid comprising a portion of the product gas circulating in the substantially closed loop. The heat transfer fluid serves as the working fluid in a turbine that produces mechanical work, electrical energy, or both. Further, the heat transfer fluid leaving the turbine may be used to preheat hydrocarbonaceous feed and free-oxygen containing gas which is then introduced into the gas generator. Optionally, by-product superheated steam may be produced at high temperature levels for use in the gas generator and as the working fluid in an expansion turbine. The high steam superheat temperatures result in higher conversion efficiencies.
    Type: Grant
    Filed: November 29, 1977
    Date of Patent: January 22, 1980
    Assignee: Texaco Inc.
    Inventors: Peter L. Paull, Rodney McGann
  • Patent number: 4181840
    Abstract: Present speed and present steam temperature are utilized in accordance with a mathematical model to evaluate present steam to turbine heat transfer and turbine heat propagation quantities, and present turbine rotor and casing surface and volume average temperatures. The model is corrected for inaccuracy based on comparison of calculated rotor to casing differential expansion with measured values, and is exercised once more with anticipated speed and steam temperature quantities to develop anticipated rotor to casing differential expansion and anticipated rotor stress. These quantities are compared with various predetermined limits to determine whether the present and anticipated speed and acceleration are within allowable limits.
    Type: Grant
    Filed: February 13, 1975
    Date of Patent: January 1, 1980
    Assignee: Westinghouse Electric Corp.
    Inventor: Robert L. Osborne
  • Patent number: 4173869
    Abstract: Apparatus and method for automatically determining and indicating that the rotor of a steam turbine has attained a predetermined minimal temperature. Means are utilized for measuring axial dimensional changes of the steam turbine cylinder and rotor due to an increased temperature and summing pertinent axial dimensional changes thereby determining the axial expansion of the rotor which in turn, through known physical properties of the rotor material, corresponds to a temperature increase. This increase of the temperature added to the initial temperature of the rotor provides the total temperature, and upon the total temperature reaching a predetermined value, the steam turbine is available to be brought up to speed and loaded.
    Type: Grant
    Filed: February 9, 1978
    Date of Patent: November 13, 1979
    Assignee: Westinghouse Electric Corp.
    Inventors: James A. Martin, Jr., Harry F. Martin, William R. Berry
  • Patent number: 4173124
    Abstract: The boiler feed water system is provided with a motor driven feed water pump and a steam turbine driven feed water pump. The control system comprises a digital computer including a flow quantity control system responsive to the degree of opening of a flow control valve and the discharge quantity of the motor driven feed water pump for controlling the flow quantity thereof, and a speed control system responsive to the speed and discharge flow quantity of the steam turbine driven feed water pump, head pressure of the feed water system and the operation of a control motor for a steam control valve of a pump driving turbine. The control is switched between the flow quantity control system and the speed control system in accordance the load of the plant.
    Type: Grant
    Filed: February 7, 1978
    Date of Patent: November 6, 1979
    Assignee: Tokyo Shibaura Kenki Kabushiki Kaisha
    Inventors: Katsumasa Fujii, Naoshi Takeda