Abstract: A power generation apparatus including a boiler feedwater pump turbine control system is disclosed. In one embodiment, a power generation apparatus is disclosed, including: a boiler feedwater pump turbine having a low pressure steam inlet and a high pressure steam inlet; a high pressure control valve for controlling admission of high pressure steam to the high pressure steam inlet; a low pressure control valve for controlling admission of low pressure steam to the low pressure steam inlet; and a control system operably coupled to the high pressure control valve and the low pressure control valve, the control system configured to close the low pressure control valve and prevent flow of the low pressure steam to the boiler feedwater pump turbine in response to a request for increased power output from a power grid.

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 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 for controlled recovery of thermal energy and conversion to mechanical energy. The system collects thermal energy from a reciprocating engine, specifically from engine jacket fluid and/or engine exhaust and uses this thermal energy to generate a secondary power source by evaporating an organic propellant and using the gaseous propellant to drive an expander in production of mechanical energy. A monitoring module senses ambient and system conditions such as temperature, pressure, and flow of organic propellant at one or more locations; and a control module regulates system parameters based on monitored information to optimize secondary power output. A tertiary, or back-up power source may also be present. The system may be used to meet on-site power demands using primary, secondary, and tertiary power.

Abstract: An exemplary steam plant having a steam circuit which includes a superheater defining a boundary between a superheated steam region and an unsuperheated steam region. The steam circuit includes a branch, from a superheated steam region of the steam circuit, with a branch valve and a steam desuperheater upstream of the branch valve. The desuperheater provides cooling to the branch during flow mode operation of the branch. During a no flow mode, a first preheat line and a second preheat line provide the cooling by supplying unsuperheated steam to the branch and directing this flow through to a lower pressure region of the steam circuit.

Abstract: A waste heat regeneration system includes a pump, a coolant boiler, an exhaust gas boiler, an expander, a condenser, a gas-liquid separator and a supercooler. A flow control valve maintains a temperature difference (T1-T2) at a predetermined value or less by adjusting the amount of an operating fluid which flows in a bypass flow path through the control of an opening degree based on a pressure difference (P1-P2) corresponding to the temperature difference (T1-T2) between the temperature (T1) of the operating fluid on the upstream side of the supercooler and the temperature (T2) of the operating fluid on the downstream side thereof. Accordingly, the degree of supercooling is prevented from becoming excessive and the waste heat regeneration efficiency of a Rankine cycle device can be maintained.

Abstract: The air cooling system and method for a heat recovery steam generator (HRSG) inlet provides a combined cycle power plant utilizing a powerful fan coupled to ductwork connected to pipes that enter the HRSG inlet duct coupled to an exhaust duct of a Combustion Turbine (CT) for lowering the temperature of the CT exhaust gas provided to the heat recovery steam generator by the CT. The cool air injection system is utilized during low load operation or startup of the CT to ensure that spray water from an inter-stage desuperheater in an HRSG is fully evaporated prior to entering the downstream superheater or reheater. A feedback system includes temperature elements measuring the mix temperature that regulates the cooling air injection rate into the HRSG inlet.

Abstract: A method and apparatus are disclosed for alleviating the problem of windage heating when flow, in a turbine running at full speed, no load, decreases greatly at the exhaust of the high pressure sections of the turbine. Valves connecting the different pressure levels of a heat recovery steam generator to the input of the turbine are adjusted to mix steam coming from the different pressure levels to create desired steam conditions at the inlet and the exhaust output of the turbine that allow the use of existing steam path hardware and thereby reduce the cost of such piping. In an alternative embodiment for a single pressure HRSG, high pressure saturated steam is extracted from the HSRG evaporator and then flashed into superheated steam when passing thru a control valve, that is then used to create the desired steam conditions at the inlet and the exhaust output of the turbine.

Abstract: Control means (32) that controls the actuation of Rankine cycle (8) is provided. An evaporator (10) is capable of absorbing heat from the waste heat of the internal combustion engine (4) with an upper limit of preset maximum heat absorption amount and transferring the heat to working fluid. The control means (32) controls the flow rate of the working fluid so that the working fluid evaporated by the evaporator (10) comes into a superheated state in a heater (18), when the working fluid enters the evaporator (10) at a flow rate equal to or lower than preset flow rate at which the working fluid can absorb the preset maximum heat absorption amount of heat, and controls the flow rate of the working fluid so that the working fluid that overflows the evaporator (10) is evaporated by the heater (18) and then comes into the superheat state, when the working fluid enters the evaporator (10) at a flow rate higher than the preset flow rate.

Abstract: A system for the control of an indirectly heated gas turbine comprising a primary system of controlling the temperature of heated compressed gas entering the expander, and an independent secondary system which includes a safety valve for instantaneous release of heated compressed gas to the atmosphere. The primary system controls system gas temperature and power output by modulating a flow of unheated compressed gas which bypasses the heat exchanger and mixes with the heated gas leaving the heat exchanger to produce a lower temperature gas entering the expander. The secondary system provides a backup means of overspeed prevention, and includes a safety valve to instantly discharge to the atmosphere hot compressed gas upstream of the expander by being responsive to the speed of the turbine. The safety valve includes a frangible membrane clamped between parallel flanges within the ducting, and further includes a dagger assembly for rupturing the membrane.

Abstract: In a method of operating a steam turbine which consists of at least two separate turbine sections (11, 15), working at different pressures from one another, and works with at least one reheat, in which arrangement the steam is directed to at least one reheater (13) after flowing through the separate turbine section of higher pressure (11), is heated in said reheater (13) and is then fed to the separate turbine section of lower pressure (15), the separate turbine section of lower pressure (15) is fed with cooler steam during the starting and run-up phase than during full-load/continuous operation.

Abstract: A boiler starting system for starting a boiler which has a superheater and at least two reheaters. The boiler starting system has a steam extracting line for extracting the steam from the steam inlet side or an intermediate portion of the superheater, and a steam supply valve by which the extracted steam is supplied to the reheaters. The flow rates of steam through the superheater and each reheater are controlled independently to realize optimum steam temperature rising characteristics, without requiring increase in the capacities of valves and other elements of the starting system.

Abstract: A steam turbine system which includes a steam generator and a steam bypass path for bypassing steam around the turbine. The outlet throttle pressure of the steam generator is controlled by controlling admission of steam into the bypass path by means of a bypass valve. A desired throttle pressure set point is generated which is independent of steam flow and this set point is compared with the actual throttle pressure for governing the bypass valve during turbine start-up. When the turbine is fully operational the bypass valve control is effected by a comparison of the actual throttle pressure with the desired throttle pressure set point plus some bias.