Abstract: In a steam system having a turbine driven by steam supplied from a high-pressure header to a low-pressure header, when the pressure in the low-pressure header drops, a turbine bypass valve is opened and the high-pressure side steam is supplied to the low-pressure side header in a normal control. When the turbine is tripped, steam is rapidly flow into the low-pressure side header and its pressure temporally increases. the steam in the low-pressure header is discharged through a discharge valve. After that, if a steam supply from the low-pressure header to another process increases, the discharge valve is closed. After the discharge valve is fully closed, an after-trip control is performed in which the opening of the turbine bypass valve is increased at an earlier timing than the normal control for preventing the steam amount in the low-pressure header to be too small. The control stability of the steam system when the turbine is tripped can be enhanced.

Abstract: A water recirculation system for a steam power plant includes a tapoff line which receives water from a downcomer, and an economizer link which receives water from the tapoff line and transports the water to an economizer.

Abstract: A turbine system includes a valve coupled to a leak off line from a leak packing of a first turbine, the valve controlling a first steam flow used to maintain a constant self-sustaining sealing pressure to a second turbine across numerous loading conditions. A related method is also provided.

Abstract: A waste-heat recovery system for a waste-heat source, made up of an ORC (Organic-Rankine Cycle) postconnected thereto. The waste-heat source is connected with the heating device of the ORC as well as an expansion machine, coupled to a generator, for steam expansion in the ORC, which has magnetic bearings with an associated control device and a power supply via a direct current intermediate circuit of a generator frequency converter. The design and safe operating behavior of a waste-heat recovery system made up of an ORC post-connected to a waste-heat source are optimized. In a power supply failure, the electric energy that a down-running generator continues to generate is used to supply the magnetic bearings with the associated control device in order to ensure a safe operation in the event of a power supply failure.

Abstract: Various thermodynamic power-generating cycles are disclosed. A turbopump arranged in the cycles is started and ramped-up using a starter pump arranged in parallel with the main pump of the turbopump. Once the turbopump is able to self-sustain, a series of valves may be manipulated to deactivate the starter pump and direct additional working fluid to a power turbine for generating electrical power.

Abstract: A steam system control method applied to a steam system including: a low-pressure header storing low-pressure steam; a high-pressure header storing high-pressure header; a steam turbine connected between them; and a turbine bypass line introducing controlled amount of steam from the high-pressure header to the low-pressure header by bypassing the steam turbine. The low-pressure header has a blow-off valve for discharging excessive steam to the outside. The steam system control method includes: a normal time blow-off valve control step of PI controlling the opening of the blow-off valve; and a trip time blow-off control step of controlling the opening of the blow-off valve by changing the MV value to a predetermined trip time opening set value when the turbine is tripped.

Abstract: A system configured to decrease the emissions of a power plant system during transient state operation is disclosed. In one embodiment, a system includes: at least one computing device adapted to adjust a temperature of an operational steam in a power generation system by performing actions comprising: obtaining operational data about components of a steam turbine in the power generation system, the operational data including at least one of: a temperature of the components and a set of current ambient conditions at the power generation system; determining an allowable operational steam temperature range for the steam turbine based upon the operational data; generating emissions predictions for a set of temperatures within the allowable steam temperature range; and adjusting the temperature of the operational steam based upon the emissions predictions.

Abstract: A waste heat recovery system is provided. The waste heat recovery system includes a gas separation apparatus that includes a chamber and at least one membrane positioned within the chamber. The gas separation apparatus is configured to produce a retentate that includes at least a combustible gas and a permeate that includes at least a waste gas, wherein the waste gas includes at least a noncombustible gas. Moreover, the waste heat recovery system includes a burner that is coupled to the gas separation apparatus, wherein the burner is configured to receive the permeate and to combust the permeate such that heat is generated from the permeate. Further, a heat recovery steam generator is coupled to the burner and configured to recover heat generated by the burner.

Abstract: In a plant including a system which is provided with a steam generator 2, a turbine 3, 5, a condenser 6 and a heater 7 and in which non-deaerated water circulates, and a pipe, the steam generator 2, the heater 7 and 8 of the system which comes into contact with the non-deaerated water is deposited with a protective substance.

Abstract: An Organic Rankine Cycle (ORC) system includes a rotor volume at sub-atmospheric pressure, a working fluid sprayed into the rotor volume.

Abstract: The invention relates to a working fluid for a steam circuit process carried out in a device comprising a steam generator, an expander, a condenser, and a reservoir for the working fluid, comprising a working medium that evaporates by the addition of heat in a steam generator, performs mechanical work by expanding in the expander during the steam phase, and condenses in the condenser; an ionic fluid serving as an antifreeze component and having a melting point in the reservoir below the freezing point of the working medium, wherein the decomposition temperature of the ionic fluid is above the evaporating temperature of the working medium in the steam generator.

Abstract: A nitrogen pressure-based engine device featuring a main engine chamber with a turbine blade system; a liquid nitrogen storage tank; a heater/vaporizer chamber for converting liquid nitrogen to gas nitrogen fluidly connected to the storage tank and to the nozzle block of the main engine chamber; a pressure condenser for condensing gas nitrogen to liquid nitrogen fluidly connected to the main engine chamber and to the storage tank; wherein liquid nitrogen flows from the storage tank to heater/vaporizer chamber then gas nitrogen flows to the main engine chamber via the nozzle block, the gas nitrogen drives rotation of the turbine blade system, the gas nitrogen then flows to the pressure condenser to be condensed to liquid nitrogen, the liquid nitrogen then flows from the pressure condenser to the storage tank.

Abstract: A method for improvement of a fossil fuel energy conversion into electrical energy for the simple sub- and supercritical steam cycle is proposed through introduction of additional regenerative cycle duties to improve the evaporation rate per unit of fuel burned, thus minimizing condenser heat loss of the working media. The additional duties provide a supplemental energy credit in the form of heat input to a steam generator where a modified combustion process is realized to convert fossil fuel into carbon monoxide and hydrogen at atmospheric pressure and thus achieving an essential reduction of nitrogen oxides (NOx) formation. The additional duties also involve a direct contact heat transfer to recover latent and thermal energy, contained in the discharged combustion products to provide yet another energy credit that satisfies both conventional and/or added regenerative cycle duties.

Abstract: A method of cooling a turbine having internal moving components to a predetermined temperature is disclosed. The method comprises taking the turbine offline. While the turbine is offline, nitrogen is flowed through the turbine until the turbine reaches the predetermined temperature while controlling the flow of nitrogen from at least one injection point to prevent damage to the moving components of the turbine by achieving uniform cooling of the internal moving components. Then the flow of nitrogen is stopped. A method and assembly for cleaning a turbine having a deposit formed on an internal surface of the turbine is also disclosed.

Abstract: The invention relates to a method for increasing the steam mass flow of a high-pressure steam turbine of a steam power plant, particularly a steam power plant including reheating, during a start-up phase of the steam power plant, particularly also during an idle period of the steam power plant, wherein at least one electric consumer is connected upstream of a generator of the steam power plant before synchronization with a power supply grid. The invention further relates to a steam power plant, comprising a generator, a high-pressure steam turbine, and at least one electric consumer, which can also be connected during a start-up phase of the steam power plant, particularly also during an idle period of the steam power plant, in order to increase a steam mass flow of the high-pressure steam turbine before a synchronization process of the generator with a power supply grid.

Abstract: Disclosed herein is an approach that uses a motor protection system to assist in determining power plant metrics. In one aspect, a motor protection system obtains operational data from motor-driven sub-processes operating within a power plant. A controller receives the operational data and determines power plant metrics that may include net power plant output and costs each of the motor-driven sub-processes has on the overall operation of the power plant. In another aspect, the controller may partition the power metrics into one or more user-specified groupings for viewing thereof.

Abstract: A method for removing hot gas deposits from a system via pressure pulses is provided. The method includes regulating a flow of a mixture of detonation fluid and oxidizer into an expansion chamber; and generating a detonation within the expansion chamber by igniting the mixture of detonation fluid and oxidizer in the expansion chamber producing a high-pressure wave, the high-pressure wave propagating along a fluid path of the system in a supersonic rate removing hot gas deposits in the fluid path while the system is in fired operation, the expansion chamber directing the high-pressure wave towards the fluid path of the system.

Abstract: The present invention is directed to a turbine seal system. The turbine seal system captures working fluid which is escaping from a closed loop thermodynamic cycle system, condenses the captured working fluid, and returns the condensate back to the thermodynamic cycle system. The turbine seal system is configured to apply nitrogen, or other non-condensable, or other material, to capture or mix with the escaping working fluid. The combined mixture of working fluid which escapes the turbine and the nitrogen utilized to capture the working fluid is evacuated by an exhaust compressor which maintains a desired vacuum in a gland seal compartment of the turbine seal. The combined mixture can then be sent to a condenser to condense the working fluid vapor and evacuate the non-condensables, forming a working stream. Once the non-condensables have been evacuated, the working stream is pumped to a higher pressure, and prepared to be re-introduced into the thermodynamic cycle system.

Abstract: A method for the application and/or renewal of a protection for a thermal barrier coating system of a heat engine involves a thermal barrier coating system that includes a bond coat layer (2) and a thermal barrier coating layer (3) of porous structure (4), wherein the bond coat layer (2) is located between and in contact with a base metal (1) of a heat engine component and with the thermal barrier coating layer (3) and bonds the thermal barrier coating layer (3) to the base metal (1).

Abstract: A carbon-dioxide-capture-type steam power generation system 1 according to the present invention comprises a boiler 6 producing an exhaust gas 5 by combusting a fuel 2 and having a flue 8; an absorbing unit 40 being configured to absorb the carbon-dioxide contained in the exhaust gas 5 into an absorbing solution; and a regenerating unit 44 being configured to release the carbon dioxide gas from the absorbing solution absorbing the carbon dioxide and discharge the released carbon dioxide gas. Further, in this system, a reboiler 49 is provided for receiving a heating-medium as heat source, producing a steam 43 and supplying the produced steam 43 to the regenerating unit 44. Additionally, in the flue 8 of the boiler 6, a boiler-side heat exchanger 61 is provided for heating the heating-medium by the exhaust gas 5 passing therethrough.

Abstract: The present application provides a steam turbine system. The steam turbine system may include a high pressure section, an intermediate pressure section, a shaft packing location positioned between the high pressure section and the intermediate pressure section, a source of steam, and a cooling system. The cooling system delivers a cooling steam extraction from the source of steam to the shaft packing location so as to cool the high pressure section and the intermediate pressure section.

Abstract: The vapour power plant with hermetic turbogenerator is claimed, such plant provided with the main thermal cycle that works with the low boiling point fluid, and characterized by an additional, internal working fluid cycle that serves to lubricate the slide bearings contained in said hermetic turbogenerator, said additional working fluid cycle consisting of the slide bearings supplying piping connected to the main working fluid cycle at the main cycle pump outlet, of the slide bearings housing, of the return piping that directs the main portion of the working fluid liquid from said slide bearing housing to the working fluid buffer container, and of the emergency slide bearings supply piping that connects said working fluid buffer container, through the emergency slide bearing supply pump, with said slide bearings supply piping, whereby non-return valves are provided before connection point of said slide bearings supply piping and said emergency slide bearings supply piping.

Abstract: An apparatus and method for the regeneration of captured gas rich capture medium such as an absorption solution and the recovery of absorbed gas therefrom, an apparatus and method for the removal and recovery of a target gas from a gas stream, and the use of the same for post combustion carbon capture on a thermal power plant are described. The apparatus and method make use of a regenerative heating process. The apparatus and method are distinctly characterized by the use of a heat pump to utilize low grade heat, for example from elsewhere in the process, as a source of thermal energy for the heating process.

Abstract: A method for retrofitting a fossil-fueled power station is provided. The power station includes a multi-housing stream turbine with a carbon dioxide separation device. As per the method, a suction capability of the steam turbine is adapted for an operation of the carbon dioxide separation device to a process steam to be removed. The carbon dioxide separation device is connected via a process steam line to an intermediate superheating line. Further, an auxiliary condenser is connected to the carbon dioxide separation device. On failure or deliberate switching off of the carbon dioxide separation device surplus process steam is condensed in the auxiliary condenser.

Abstract: Embodiments of the invention can provide systems and methods for pre-warming a heat recovery steam generator and associated steam lines. According to one embodiment, a method for pre-warming a heat recovery steam generator can be provided. The method can include providing heating steam from a steam source. The heating steam is directed from the steam source to a superheater so that at least a portion of the superheater can be warmed. Once exiting the superheater, the heating steam can be further directed from the superheater to at least one bypass line and maintained in the bypass line until the bypass line attains a predefined temperature or pressure. Furthermore, the method can include directing, after the bypass line attains a predefined temperature or pressure, at least a portion of the heating steam from the bypass line to a reheater so that the reheater can be warmed.

Abstract: A power plant including a steam turbine, and a steam turbine exhaust duct configured to deliver uncontaminated fluid from the steam turbine to downstream components of the power plant. The steam turbine exhaust duct includes a steam turbine exhaust duct isolation valve selectively configured to prevent fluid communication between the steam turbine exhaust duct and the downstream components of the power plant, and a steam turbine exhaust duct vent with a steam turbine exhaust duct vent valve. The steam turbine exhaust duct vent is configured to deliver contaminated fluid from the steam turbine exhaust duct to a fluid sink upon opening of the exhaust duct vent valve.

Abstract: A waste heat recovery system is provided. The waste heat recovery system includes a gas separation apparatus that includes a chamber and at least one membrane positioned within the chamber. The gas separation apparatus is configured to produce a retentate that includes at least a combustible gas and a permeate that includes at least a waste gas, wherein the waste gas includes at least a noncombustible gas. Moreover, the waste heat recovery system includes a burner that is coupled to the gas separation apparatus, wherein the burner is configured to receive the permeate and to combust the permeate such that heat is generated from the permeate. Further, a heat recovery steam generator is coupled to the burner and configured to recover heat generated by the burner.

Abstract: The present invention provides a turbine system which can start a turbine, while controlling thermal stress generated in a turbine rotor and an expansion difference, due to thermal expansion, between a casing and the turbine rotor, to be lower than defined values, respectively. The turbine system (1) according to the present invention includes the turbine (4) having a casing (2) and the turbine rotor (3) rotatably attached to the casing (2), and a main steam pipe (5) connected to an upstream portion of the casing (2). A control valve (6) adapted for controlling a flow rate of steam discharging into the casing (2) is provided with the main steam pipe (5), and a power generator (7) is coupled with the turbine rotor (3). Additionally, a starting control system (10) is adapted for controlling the control valve (6), while obtaining an operational amount of the control valve (6).

Abstract: A start-up system mixing element including; a body defining a cavity, a first inlet port disposed in the body and configured to provide a first fluid to the cavity, a second inlet port disposed in the body and configured to provide a second fluid to the cavity, an outlet port disposed in the body and configured to remove the first and second fluids from the cavity and an internal distribution pipe disposed in the first inlet port, wherein the internal distribution pipe is configured to provide the first fluid to the cavity via a plurality of holes directed toward a center of the cavity.

Abstract: A condenser is provided and includes a body into and through which steam turbine discharge is able to flow, and first and second cooling members disposed in the body, wherein the first and second cooling members are each independently receptive of first and second coolant, respectively, the first cooling member, being receptive of the first coolant, is configured to cool the discharge during at least a first cooling operation, and the second cooling member, being receptive of the second coolant, is configured to cool the discharge during a second cooling operation.

Abstract: A power plant system and a method for operating a power plant system are provided. An overload control valve is disposed in an overload line and can be actuated by means of a pressure regulator wherein the overload control valve opens before a diverting control valve opens the valve forming a bypass between the high-pressure steam inlet and the high-pressure steam outlet as soon as a target valve is exceeded.

Abstract: A vapor power generating system for generating power by using heat from a source of heat. The system has a closed circuit for a working fluid, and includes a heat exchanger assembly (1) for heating the fluid under pressure with heat from the source, a separator (8) for separating the vapor phase of the heated fluid from the liquid phase thereof, an expander (14) for expanding the vapor to generate power, a condenser (17) for condensing the outlet fluid from the expander (14), a feed pump (F) for returning condensed fluid from the condenser (17) to the heater and a return path for returning the liquid phase from the separator to the heater. The liquid phase of the working fluid contains a lubricant which lubricant is soluble or miscible in the liquid phase and a bearing supply path (21) is arranged to deliver liquid phase pressurized by the feed pump (F) to at least one bearing for a rotary element of the expander.

Abstract: A high-temperature steam turbine plant is of the top turbine type and structured as follows. It comprises a boiler building including a vertical boiler on the top of which a VHT turbine is installed; and a turbine building installed on the ground as a base. The VHT turbine and a generator connected with it are installed on the top of the boiler. The material for the portion of the steam pipe between the boiler building and the turbine building which is exposed to highest steam pressure is austenite steel which contains 50 weight % or more of ferrite steel or Fe. The inlet temperature of the VHT turbine is 675° C. or more and its outlet temperature is 550° C. or more and 650° C. or less.

Abstract: A water circulation power generation system for energy recovery includes at least one water circulation power generation system connected to a heat exchange system to obtain required water for a heat exchange process. The water circulation power generation system includes a water tank to store cooling water, a water supply pipeline and a recovery pipeline. The water supply pipeline draws water from the water tank to supply front end water to the heat exchange system. The recovery pipeline guides operational circulation water discharged from the heat exchange system and has a hydraulic power generator installed thereon driven by the operational circulation water to convert kinetic energy thereof to electric power. Thus during the operational circulation water flows to its recovery destination, its kinetic energy drives the hydraulic power generator to produce additional electric power.

Abstract: An oxygen fueled integrated pollutant removal and combustion system includes a combustion system and an integrated pollutant removal system. The combustion system includes a furnace having at least one burner that is configured to substantially prevent the introduction of air. An oxygen supply supplies oxygen at a predetermine purity greater than 21 percent and a carbon based fuel supply supplies a carbon based fuel. Oxygen and fuel are fed into the furnace in controlled proportion to each other and combustion is controlled to produce a flame temperature in excess of 3000 degrees F. and a flue gas stream containing CO2 and other gases. The flue gas stream is substantially void of non-fuel borne nitrogen containing combustion produced gaseous compounds.

Abstract: A cleaning device includes at least: a holder, a lance having a fluid distribution device, a drive unit for a translational motion of the lance in the holder, and a fluid conducting system having a feed, a return, and flow paths starting from the feed to the return and to the fluid distribution device. At least one actuating means (or actuator) is provided in order to connect the feed to the return or to the fluid distribution device as needed. Furthermore, a method involves cleaning heating surfaces of a convection section of a thermal power plant that includes spaced heat exchanger pipes using such a cleaning device.

Abstract: The present invention provides an integrated engine generator Rankine cycle power system which increases the efficiency of the use of its power output. The system comprises a closed Rankine cycle power generating unit through which working fluid flows and an engine generator, the closed Rankine cycle power generating unit including a waste heat boiler for vaporizing said working fluid by means of exhaust gases discharged from the engine generator, an expander in which the vaporized working fluid expands and performs work to drive a shaft for producing mechanical power, or an electric generator coupled thereto and adapted to produce electrical power, from both the engine generator and the expander, and an external lubrication system in fluid communication with the expander wherein one or more closed Rankine cycle power generating unit components are operationally connected to the electric generator.

Abstract: The disclosure relates to a method and apparatus for cold starting a steam turbine by preheating a steam turbine component using eddy currents. The process includes providing an electrically conducting steam turbine component, an electro-magnetic coil, and a supply of AC to the coil. The coil is located relative to the component so that the coil is capable of forming eddy currents in the component. In this location, an AC current is passed through the coil thus heating the component.

Abstract: Power plant systems and processes are described that enable recovery of at least a portion of the fuel storage energy associated with a storage system for supplying fuel to the power plant systems. A first embodiment of an energy-recovery power plant system includes at least one fuel storage container and at least one expander that can receive fuel from the fuel storage container at a first pressure and provide the fuel to the power plant at a second pressure that is lower than the first pressure. A second embodiment of an energy-recovery power plant system includes a first conduit fluidly coupling the fuel storage container and the power plant for delivering fuel from the fuel storage container to the power plant and at least one regenerative thermodynamic cycle engine thermally coupled to the first conduit such that heat may be exchanged between the fuel and a working fluid for the regenerative thermodynamic cycle engine.

Abstract: An apparatus to facilitate a start-up operation of a combined cycle or rankine cycle power plant is provided and includes a plurality of heat pipes, each of which respectively includes a first portion in thermal communication with exhaust emitted from a heat source and a second portion in thermal communication with the first portion, a cooling unit to cool the second portions of the heat pipes, and a controller which is configured to control the cooling unit to cool the second portions of the heat pipes and to thereby remove heat from exhaust via the first portions of the heat pipes.

Abstract: A system and method for waste heat recovery in exhaust gas recirculation is disclosed. The system includes an engine having an intake manifold and an exhaust manifold, an exhaust conduit connected to the exhaust manifold, and a turbocharger having a turbine and a compressor, the turbine being connected to the exhaust conduit to receive a portion of the exhaust gas from the exhaust manifold. The system also includes an EGR system connected to the exhaust conduit to receive a portion of the exhaust gas, with the EGR system including an EGR conduit that is connected to the exhaust conduit to receive a portion of the exhaust gas, a heat exchanger connected to the EGR conduit and being configured to extract heat from the exhaust gas, and a waste heat recovery system connected to the heat exchanger and configured to capture the heat extracted by the heat exchanger.

Abstract: In a moisture separator, a manifold that communicates with a steam inlet is disposed in a shell. A plurality of blowout outlets for steam is provided on a side of the manifold. A first support plate and a lower support frame are fixed to a lower part in the shell to compart a steam drift space and a drain path. A moisture separating element is provided corresponding to the manifold, and steam from which moisture is removed by the moisture separating element is heated by a group of heating tubes to flow as high-temperature reheat steam to the steam outlet. The moisture is led from the drain opening through the drain path to the drain outlet. A blocking plate blocks a part of the drain opening.

Abstract: An oil cooler is provided for a wall of an air flow passage of a gas turbine engine. The oil cooler has a heat exchanger with an oil conduit for carrying a flow of heated oil proximal to the wall of the air flow passage. The heat exchanger is arranged to transfer heat from the heated oil to the air flowing through the passage. The oil cooler further has a system for altering the flow of air across the heat exchanger such that the heat transfer effectiveness of the heat exchanger can be adjusted.

Abstract: A steam power plant, in which steam from a steam generator is received by a steam turbine, is provided and includes a conduit, a main steam control valve (MSCV) disposed along the conduit to admit the steam to the steam turbine when a characteristic thereof satisfies a threshold, a bypass line, coupled to the conduit between a super-heater and a valve, including a bypass line valve which is opened until the threshold is satisfied such that the bypass line removes a portion of the steam, an evacuator line, coupled to the conduit between the MSCV and the steam turbine, including an evacuator valve which is opened to regulate a thermal environment within the steam turbine during a start up thereof, and a warming line originating between the valve and the MSCV on the conduit and terminating downstream of the evacuator valve disposed along the evacuator line.

Abstract: A turbine for converting thermal energy into mechanical work. The turbine includes a heating system, wherein the heating system is adapted for heating the turbine in a power off state and/or a start-up phase of the turbine. The heating system may include an electrical heating device and/or a steam heating device.

Abstract: This invention provides a small, high efficiency, oil-free turbine-driven alternator (i.e. turboalternator) suitable for conversion of stored energy in a process gas to electrical power, facilitating recapture of energy during operation that would otherwise be wasted. The turboalternator includes a turbine and a generating device operatively connected together by a rotating shaft capable of rotating at high speeds. The rotating shaft is supported by foil gas bearings.

Abstract: An interface for a pressurized fluidized bed combustion facility is disclosed that enables future addition of carbon dioxide capture technology to capture facility flue gas emissions. The interface includes a gas to water pressurized heat recovery steam generator to cool facility flue gas and provide steam to the facility steam turbine generator. A VFD motor and flue gas expander are coupled to a combustion air compressor to energize the facility. The expander is synchronized over a SSS-clutch to drive the compressor. The interface in combination with carbon capture technology and methods for conditioning flue gas are also disclosed.

Abstract: Systems and methods for controlling humidity of a working fluid used to provided climate control of a mission critical application are provided. Such control may be accomplished by using a humidification system in connection with a CAS or TACAS system. The humidification system may introduce a liquid (e.g., water) into one or more, predetermined points within the CAS or TACAS system to adjust the moisture content of a working fluid used to influence the environment of a mission critical application or enclosure.

Abstract: A control device for a quick-closing valve of a steam turbine including a relief valve for reducing a hydraulic pressure opening the quick-closing valve, and a relief valve control valve arrangement having at least three valves which are hydraulically interconnected with the relief valve in such a way that the relief valve does not close the quick-closing valve unless at least two valves of the relief valve control valve arrangement are switched to a quick-closing position. The system includes a test control valve arrangement for selectively reducing and increasing the hydraulic pressure opening the quick-closing valve when the relief valve is closed.

Abstract: An object of the present invention is to provide a turbine protection device which can interrupt backflow from a deaerator to a turbine completely even if a check valve provided between the deaerator and the turbine can not interrupt the steam flow between the deaerator and the turbine completely. In order to achieve the above object, a control unit sends commands to a shutdown valve device so as to close the shutdown valve device when a differential pressure resulted from subtracting a pressure of a extraction steam from a pressure within the deaerator becomes greater than or equal to a first predetermined value. As a result, the backflow from the deaerator to the turbine is interrupted by a stop valve of the shutdown valve device.