General Electric Company

Kabushiki Kaisha Toshiba

Jens Kure-Jensen

William I Rowen

James H Moore

Bernd Artur Westphal

Donald H Davis

Ronald John Placek

Robert A Marshall

Thane Montgomary Drummond

Patrick S Coppola

Charles L Devlin

Adrian Missana

Hideaki Miyayashiki

Markus A Eggenberger

David C Gonyea

Lloyd H Johnson

Richard S Gordon

Roger Bennett Clark

Mark A Davis

Harris S Shafer

Dominic P Timo

Solomon Jenkins, Iii

Frederick C Krings

Tomoo Ofuji

A combined control/stop valve assembly for use in steam cycle plants which include at least one steam turbine, the valve assembly including a butterfly valve having a valve plate pivotable about a first axis, and a stop valve located downstream and adjacent the butterfly valve, the stop valve having a cylindrical strainer with a longitudinal axis substantially perpendicular to the first axis, the strainer having a solid portion facing the butterfly valve.

Combined valve configuration for steam cycle units

A method of operating a combined-cycle gas and steam turbine power generating system on a single shaft 16 uses as a feedback to the speed control or governor a signal 22 representing the total power output of the generator less the total output of the steam turbine 12, which is then correlated with the error signal between the actual and reference speeds to alter the fuel flow to the gas turbine. By compensating the measured generator output by subtracting a value 24 representative of the steam turbine output so that the compensated signal 26 represents the contribution of only the gas turbine 10 to the generator output, a constant settable droop speed control system may be used in a single-shaft combined-cycle steam turbine and the gas turbine system to compensate for variable heating fuel value and/or changing combustion efficiency in dry low NO.sub.x combustion systems.

Method of operating a combined cycle steam and gas turbine power

A system and method for anticipating and controlling overspeed in a combined cycle turbine of the type having a gas turbine with a fuel flow control valve and a steam turbine with at least one steam control valve both disposed on a single shaft and having a heat recovery steam generator heated by said gas turbine and connected to supply steam to the steam control valve, the combined cycle turbine having a unified control system and driving a load. Below a preselected shaft speed the gas turbine fuel command signal controls power. Above the preselected shaft speed the steam turbine speed signal also controls power. Anticipation of overspeed under severe transient load changes, such as loss of electrical load, is provided by a power load unbalance system, wherein gas turbine power and steam turbine power responsive signals are summed after proportionately scaled power responsive signals exceed load by a preselected amount, whereby appropriate action is taken to reduce power before significant overspeed can occur.

Overspeed anticipation and control system for single shaft combined

A method for starting and loading a combined cycle turbine of the type having a gas turbine with a fuel flow control valve and a steam turbine with at least one steam control valve both disposed on a single shaft and having a heat recovery steam generator heated by said gas turbine and connected to supply steam to the steam control valve, the combined cycle turbine having a unified control system and driving a load and also having an auxiliary steam source connected to the steam control valve. The improved method comprises starting and cranking the combined unit by controlling steam from the auxiliary steam source with the steam control valve, initiating and controlling fuel flow to the gas turbine with the fuel flow control valve, initiating combustion, controlling acceleration of the combined unit with the steam control valve, transferring acceleration control of the combined unit to the gas turbine fuel flow control valve, and accelerating the combined unit to rated speed. The method further includes the steps of synchronizing the combined unit to the line, substituting steam from the heat recovery steam generator for that from the auxiliary steam source, and opening said steam control valves to a full open position.

Control system for single shaft combined cycle gas and steam turbine unit

Slotted, fluid-flow dividing therefor employed in a fluid valve not only to reduce noise but also to shift the frequency spectrum of the noise energy. The slotted therefor is formed integrally with the valve seat. Additionally, the cross-sectional shape of the slots may be varied to more precisely control the lift characteristic of the valve.

Silent valve

A thermal performance monitor informs the operator and result's engineer of the economic losses, efficiencies, deviation in heat rates and power losses of operating a steam turbine-generator system at its controllably selected pressure and temperature. Specifically temperature and pressure signals are generated at various points in the system along with the control valve position signal and the electric output signal from the electric generator. This data is processed along with the corresponding design values and the economic losses due to temperature deviation, pressure deviation and exhaust pressure deviation from design are calculated. Other calculations produce a comparison of efficiencies of the turbines in the system and consequential power losses.

Steam turbine-generator thermal performance monitor

A signal representing the electrical output power of a steam turbine-generator is fed back to a control system. A signal representing the boiler steam pressure is also fed to the control system. A control signal for controlling valves feeding steam to the steam turbine is gain controlled between one and zero in the presence of a negative rate of change of steam pressure less than a predetermined value. At other negative and all positive values of rate of change of steam pressure, the control signal is unaffected. In one embodiment, a linear relationship is employed for controlling the gain for increasingly negative values of the rate of change of steam pressure. At an extreme negative value, the gain is controlled to zero, whereby the a load reference signal remains unchanged.

Steam turbine control with megawatt feedback

A low collapse speed, self priming, lubricating oil pumping system for a turbomachine, operatively driven by the turbine main shaft, is disclosed. In a preferred form, the invention includes a permanent magnet generator operatively coupled to shaft of the turbine-generator or turbomachine being lubricated and driven thereby to produce an electrical output; an induction motor directly connected to the electrical output of the permanent magnet generator without intervening protective devices such as fuses, switches, and so forth; and a positive displacement pump located in or in proximity to an oil reservoir and driven by the induction motor to pump oil from the reservoir at a flow rate and pressure sufficient to supply oil to the turbine-generator or turbomachine during all operating phases thereof during which lubrication is required.

Low collapse speed lube oil pumping system for turbomachinery

Apparatus for individually isolating the hydraulic actuators of steam valves for a steam turbine while the turbine remains in operation and while all other steam valves associated with the turbine remain functional. Isolation is achieved by providing a manual isolation valve for blocking the flow of hydraulic fluid from a main supply; a flow restrictor to limit the inflow of hydraulic fluid; and a flow direction control means to limit hydraulic fluid to flow only from the actuator toward an emergency trip hydraulic fluid supply.

Apparatus for individual isolation of hydraulically actuated valves

An apparatus for continuously monitoring the alignment condition of a thrust bearing based on a pair of temperature differences is adapted to utilize either analog or digital means. The monitor is particularly applicable for use in large turbines, particularly those coupled to generators for the production of electric power. Bearing misalignment and other variables are determined from temperature measurements of the oil feed temperature and from two temperature measurements made on diametrically opposite portions of the bearing surface. The apparatus of the present invention is made possible by observed predetermined relations between certain computed temperature differences which relate bearing thrust and misalignment moment and which also relate minimum oil film thickness and actual misalignment slope.

Thrust bearing misalignment monitor

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. The microcomputer hierarchy includes an input and calculations computer having means for interfacing with analog input data sources and sensors which report on various operating parameters of the turbine-generator and from which thermal and mechanical stress and other derived quantities are calculated; a display and communications computer adapted to interface with a plant computer and with an operator control panel and other display and readout devices whereby operating personnel may interact with the control system; and a control computer, standing at the top of the hierarchy, for receiving information from the other computers, for making decisions based on that information and, through input/output ports, for providing the electrohydraulic control system with directions for optimal control of the turbine-generator within its thermal and mechanical limitations. The dedicated supervisory controller provides a plurality of operating modes.

Dedicated microcomputer-based control system for steam turbine-generators

A method and apparatus is disclosed for determining whether certain rotor stress values are exceeded during the thermal cycle of a turbomachine. The invention takes into account the rotor material and the behavioral characteristics of the rotor material above and below the Fracture Appearance Transition Temperature (FATT). The acquired data is stored to develop a rotor history useful in determining a rotor condition for maintenance and longevity purposes and further useful in determining the operating pattern of the turbomachine.

Bore stress limit index

A testable protective system for an operating system is provided with redundant trip components serially connected to redundant lock-out components. The trip components are signalled by fault sensors which monitor critical conditions of the operating system. These trip components produce an output indicative of such conditions, which output is fed to certain actuated devices which may either correct the condition or shut down the operating system until the cause of the problem can be determined and the necessary repairs made. When it is desired to test one of these trip components, the operator activates the corresponding lock-out component and performs the necessary test. The activation of this lock-out component has an effect of making the protective system output signal (the output to the actuated devices to correct the fault or shut the system down) independent of the output of that trip component when it is being tested. Should an operator mistakenly activate both lock-out components at once, the protective system output signal is a function only of the fault sensor input to a first trip component and a driving signal to the protective system. Thus, even if both lock-out components are activated at once, a fault signal to the first trip component will effect a fault output signal from the protective system to the actuated devices.

Growing community of inventors

Schenectady, NY, United States of America

Jens Kure-Jensen