Abstract: A system for simulating and optimizing a powerhouse, designed to furnish electrical power to a process plant, incorporates a plurality of units for simulating operation of the individual components of the powerhouse, and for calculating the cost of operation of the system as a whole, including the cost of fuel for the powerhouse components and the cost of purchased power needed to satisfy the power demand of the process plant beyond the capacity of the powerhouse. An adaptive search routine varies all of the operative parameters of the powerhouse, on a random basis, and repeats the simulation, in order to identify a combination of parameters which represents a lower cost solution. The range of random variation is reduced, as lower cost solutions are not found within a given number of repetitions, in order to identify a precise convergence on the optimum solution.

Abstract: A plant activation tracking and display apparatus for use in a plant in which various points of plant components are represented by nodes including at least one system input node and at least one system output node, the adjacent nodes being connected to one another by means of fluid passages, with a pump unit and/or valve unit for creating a fluid flow in a specified direction being provided in the middle of each of the fluid passages in desired positions. An output device successively tracks each of the categorized fluids with a specified phase from the system input node to the system output node, and sequentially displays the array of the tracked nodes in one direction.

Abstract: Method for improving the heat rate of a steam turbine operated in a partial-arc mode includes sequential closing of control valves to establish a first arc of admission at which pressure drop on a first control stage reaches a predetermined level. Steam pressure to the turbine may then be reduced in combination with valve closing to maintain first stage pressure at or below the predetermined level. In a further method, low power operation is achieved by maintaining a constant arc of admission while simultaneously moving all open valves toward a closed position.

Abstract: An engine system using refrigerant fluid is capable of utilizing the heat produced by an external high-efficiency hydrocarbon fuel combustion process. The heat from that process is utilized to transform the refrigerant fluid from a liquid state to a gaseous state in a cycle which includes extracting work from the fluid in the gaseous state in a high-compression-ratio piston engine. The cycle further includes transforming the fluid in the gaseous state back to the liquid state in a condenser, and then feeding that fluid under pressure to a heating chamber where the combustion process heat again returns it to the gaseous state at high pressure and temperature. The engine system has a higher efficiency than hydrocarbon fuel combustion engines, and has particular application to use in automobiles. One preferred refrigerant fluid for this engine system is 2,2,Dichloro-1,1,1,Trifluoro-Ethane.

Abstract: An adaptive oil lubrication system for a marine propulsion system having a variable speed oil pump controlled by a microprocessor. The speed of the pump and, thus, the oil flow rate is varied to track the demand for lubrication by the propulsion system. A microprocessor monitors the propulsion system and calculates the appropriate speed of the oil pump to generate the oil flow needed by the propulsion system.

Abstract: In conjunction with a method and apparatus for regulating the power of a steam power plant block, an improved method and an improved apparatus for restoration of a given throttling of the turbine inlet valves as a conclusion to a regulating process for stabilizing a sudden or abrupt elevation of the load set point is proposed by the invention. The necessary storage of fresh steam takes place without influencing the electrical output power or the regulating devices necessary for regulating it with the aid of a separate closed control circuit.

Abstract: The present invention provides a method and corresponding apparatus for detecting open and short circuit faults in a valve position sensor. According to one aspect of the invention, a fuel or steam valve (2) in a turbine system is automatically opened and closed by a positioner/sensor combination (1, 36, 32). In the event a fault occurs in the position sensing circuitry, a fault signal is immediately produced which allows appropriate action to be taken, e.g., closing the valve, before the turbine is damaged.

Abstract: A steam turbine system has a plurality of moisture-separator-reheaters (MSR) each connected via a respective drain line to a corresponding drain receiver. Each drain receiver includes a further drain line coupled through a flow control valve to a common line. The common line empties into a drain cooler connected at the highest pressure end of a series of feedwater reheaters. The drain cooler dumps through another flow control valve to one of the feedwater heaters. Each of the drain receivers includes a pressure sensor and liquid level sensor. A control processor monitors the pressure sensors and selects the drain receiver subjected to the lowest pressure. The processor then fully opens the valve associated with the selected drain receiver and thereafter regulates the liquid level in the others of the drain receivers by adjustment of their respective flow control valves in response to their respective level sensors.

Abstract: A method and apparatus for controlling the operation of a steam turbine system, which system includes a source of steam under a controllable pressure, a plurality of governor valves connected between the source and the turbine first stage, each governor valve being movable between two selected positions each creating minimum steam flow throttling losses, a system control device (2) for producing a system control signal representative of the desired power level to be supplied by the turbine system, and a governor valve control (8) connected for producing a valve control signal in response to an input signal and for positioning each governor valve in accordance with the value of the valve control signal. During operation, the input signal to the governor valve control (8) is given a value which is based on the system control signal and which causes the valve control signal to have a value which will place each governor valve at least approximately at a selected position.

Abstract: 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.

Abstract: Method for improving the heat rate of a steam turbine operated in a partial-arc mode includes sequential closing of control valves to establish a first arc of admission followed by a reduction of steam pressure to a predetermined level. Additional valves are closed to bring the admission arc to an optimum value and power reduction is thereafter affected by pressure reduction. In a further method, low power operation is achieved by reducing the arc of admission below optimum when steam pressure has been reduced to a minimum value.

Abstract: A method and apparatus for continually monitoring the operating state of a set of governor valves (42,60) in a steam supply system for the first stage of a high pressure turbine during operation of the turbine, the system including a source including a throttle valve (40) for supplying steam at a defined pressure to the governor valves (42,60) and a plurality of nozzles (44) each connected to deliver steam from a respective governor valve (42,60) to a respective turbine inlet region, by the steps of: monitoring (52) the pressure at the outlet of each governor valve (42,60); monitoring (50,54) the pressure at the inlet to the throttle valve(s) (40) and at the turbine first stage; and comparing (56) the monitored outlet pressure of each governor valve (42,60) with the monitored pressure at the throttle valve inlet and at the turbine first stage in order to provide an indication of the operating state of each governor valve (42,60) and to detect and alert power plant operators of valve malfunctions or inefficien

Abstract: A thermally powered electrical generating system for use in a space vehicle is disclosed. The rate of storage in a thermal energy storage medium is controlled by varying the rate of generation and dissipation of electrical energy in a thermally powered electrical generating system which is powered from heat stored in the thermal energy storage medium without exceeding a maximum quantity of heat. A control system (10) varies the rate at which electrical energy is generated by the electrical generating system and the rate at which electrical energy is consumed by a variable parasitic electrical load to cause storage of an amount of thermal energy in the thermal energy storage system at the end of a period of insolation which is sufficient to satisfy the scheduled demand for electrical power to be generated during the next period of eclipse. The control system is based upon Kalman filter theory.

Abstract: A method for automatically calibrating a controller for a valve controlled system follows consistent procedures to make precise adjustments to valve characteristics. The controller is placed in a calibration mode, then the valve settings are modified over a full range of operation. At predetermined levels of operation, the valve settings are maintained at preset values while system performance is measured. After the full range of valve operation has been covered, adjustments are made to the correspondence between the valve settings and the levels of operation in dependence upon the differences between the measured system performance and the predetermined levels of operation. This procedure is repeated to provide average values and also to make changes to valve characteristic curves corresponding to different modes of operation such as single valve and sequential valve modes. Other control parameters may be adjusted by evaluating system performance during normal operation.

Abstract: A method and apparatus for determining the steam temperature in the impulse chamber at the first stage exit of a multistage high pressure steam turbine utilizes measurement of steam pressure in the impulse chamber and steam pressure and temperature at the exhaust as inputs to a digital computer. The functional relationships among steam pressure, temperature, specific volume, enthalpy and entropy are stored in the computer memory, and used with these measured quantities to iteratively calculate the steam temperature at the impulse chamber.

Abstract: In a steam turbine power plant, a deaerator is heated and pressurized by extraction steam from the steam turbine for the purpose of preheating feedwater to the power plant boiler. Under certain conditions, the available steam to the deaerator is insufficient to adequately maintain pressure in the deaerator leading to steam voids with a rapid rise in deaerator water level which could cause damage to the deaerator, feedwater pumps or the turbine and lead to a power plant shutdown. A second source of steam is available to provide steam under these conditions and a control system for controlling the steam input into the deaerator is shown. Under conditions of falling pressure, if a certain rate is exceeded, the second source of steam is input into the deaerator to maintain adequate pressure for stable operation.

Abstract: A steam turbine inlet valve control system includes separately tunable valve characteristics for single valve and sequential valve operation modes. The sequential valve characteristics include both normal and alternate sequences which can be selected during operation of the steam turbine. The characteristics may be displayed to an operator and modified by graphical manipulation to simplify tuning the control system's characteristics to the steam turbine's operation. The control system also performs direct tracking of flow through the valves by converting sensed position signals to individual valve flow signals using a lift-to-flow conversion characteristic. Individual valve flow signals are summed and corrected for choked flow conditions to produce a tracked flow demand signal.

Abstract: Control sub-systems, modularized on both a hardware and software basis are configurable to supplement an existing cogeneration system package, controlling and/or monitoring only essential control points of such cogeneration system to select thermal or electrical load following modes, or on and off modes, and to optimize the operation of the cogeneration system handling only a few control points. Various inputs of the cogenerator system are sensed and used in generating diagnostic or performance evaluation routines. Personality modules adapt the sub-systems to a particular cogeneration package type, and permit tailoring for economic considerations, such as local rates and schedules, performance characteristics and operating constraints of the associated cogeneration package and the like.

Abstract: A closed loop solar collector system (10) includes a fluid receiver (12) for collecting solar heat to vaporize a working fluid therein. A uniflow engine (15), connected to the receiver (12), is powered by the vaporized fluid to power a water wheel (19). The engine (15) includes a single piston (37) acting directly upon a pair of normally closed intake valves (50) projecting into the engine cylinder (35). Under low boiler pressure conditions, a spring loaded connecting rod (62) having depending arms (64) each engaging one of the intake valve rods (54b) when in a normally raised position coordinates simultaneous opening or closing of the valves (50) with a detent mechanism (63), enabling the piston (37) to operate in a nonexpanding state.

Abstract: The invention is a solar-powered, Rankine cycle, two fluid engine useable for many functions, especially for pumping liquids from the ground such as water or oil in remote locations. The engine driven by heat energy collected in standard collectors or in solar ponds utilizes a heated fluid such as water to transfer the heat from the collectors to a tank where a volatile working medium is transformed into a pressurized vapor. The heated working medium is then fed to a double acting cylinder where work is extracted from the working medium. The engine's valving is controlled by electric switches. The storage batteries are continuously charged by solar energy. If the source of energy is heat collected by standard collectors, a tracking device for the collectors, also driven by solar power, is incorporated in order to attain high collection efficiencies. The engine is used to drive either mechanical or hydraulic pumping devices.

Abstract: A control apparatus for electric power plant comprises turbine speed control means for detecting the speed of a turbine coupled to an electric generator to control the turbine speed by controlling a steam flow supplied to the turbine on the basis of the detected speed, pressure control means for controlling the pressure in a steam generator on the basis of the pressure of the steam generator, and correcting means for correcting the steam flow supplied to the turbine only when fluctuation in the pressure of the steam generator brought about by rapid change of a set load value is deviated from a predetermined range in which the steam pressure is allowed to vary, the correction of the steam flow being made in correspondence to the deviation.

Abstract: A power system for use in converting solar energy into useful and stored energy available as output power capable of operating diverse types of power-driven units, such as electric generators, air conditioners, etc. The power system includes solar heat collector means, motor means a compressor system and power storage means. The solar collector system utilizes the sun's rays to heat a liquid medium, such as a refrigerant and convert it into a gas, with the expanded gas being delivered to large motor means. The large motor means is used in part to operate a power-driven unit and in part to drive a substantially smaller motor means operable to pressurize a compressor gas in accordance with the principle of hydraulic pressurization. The combination of the large and small motor means allows the pressure of the solar heated medium to greatly magnify the pressure developed on the compressor gas, which is transferred to the power storage system.

Abstract: A system for the operation of once-through boilers which utilizes variable throttle pressure over a very wide load operating range is disclosed. The system utilizes a valving arrangement permitting the turbine valve (22) to be opened to a predetermined open position, typically 70 percent of its full open position, as soon as possible during the system loading process, maintaining the turbine valve (22) in this predetermined open position while the flow of steam from the boiler is being varied by a control valve (40) and the output pressure of the boiler is varying accordingly, and then allowing the turbine valve (22) to open further from the predetermined open position when the system reaches full design pressure so as to vary the flow of steam from the boiler while the output pressure thereof is maintained substantially constant. In this manner, the boiler is operated at a variable output pressure over a very wide load operating range.

Abstract: A steam turbine governor system including two governor electronic sections for producing a turbine valve opening command to control the opening of steam valves thereby controlling a flow of steam into the turbine in dependence upon a difference between an actual turbine speed and a target turbine speed and a target turbine load. One governor electronic sections is actually used for controlling the opening of the steam valves, while the other governor electronic section is a stand-by. A first value relating to the turbine speed acceleration rate based on the turbine valve opening command produced by each of the governor electronic sections is obtained so that the first values are obtained parallelly and independently of each other in the two governor electronic sections. Turbine valve opening commands produced by the respective governor electronic sections are compared with each other and produce a start signal when the difference between them exceeds a predetermined level.

Abstract: An automatic control system for a thermal power plant comprises a master controller controlling a turbine in response to an externally applied load command signal, and producing a boiler input command signal by correcting the load command signal on the basis of the detected pressure of main steam generated from a boiler, and a water/steam process controller, a fuel process controller, a combustion process controller and a draft process controller to all of which the boiler input command signal is applied from the master controller. The process controllers apply control signals to equipments controlling a water/steam process, a fuel process, a combustion process and a draft process respectively among the terminal actuating equipments of the various parts of the boiler.

Abstract: A fluid-driven power plant includes a motor and a combustion energy input device combined in a closed, pressurized system. A balanced cylinder provides variable low pressure fluid storage within the system and also operates the compression stroke of the combustion device. A compression acceleration cylinder in direct fluid communication with the accumulator assists in the compression stroke allowing the balance cylinder to be operated at a lower pressure. An opposed combustion piston configuration balances the forces within the system. A device for monitoring the speed of the combustion pistons allows for compensation for misfires and variations in the heating value of fuel. Apparatus is provided to adjust the sensitivity of the power demand controls and to anticipate a future demand for high power output.

Abstract: In a steam and power cogeneration system optimization results for steam flow and power are calculated off-line recurrently based on actual demand and control is effected on a multiplane basis upon selection of a new plane of control defined by a new status and configuration of the system network, the optimization results for such particular plane being selected and control performed at the time of plane change. Pressure reducing valves are positioned initially at the time of plane change in accordance with the optimization results for the new plane. Pressure reducing valves are positioned for flow tuning about such initial valve positioning.

Abstract: A microprocessor-based controller for an extraction type steam turbine-generator unit capable of selecting from a variety of predetermined control strategies and implementing corresponding valve position control loops by generating appropriate valve position control signals in accordance with operator-chosen setpoint signals and turbine operating level signals. In a particular control strategy, automatic system frequency correction is achieved in a load control mode upon separation of the turbine-generator from the utility power grid, by detecting turbine speed deviation beyond predetermined limits and correcting turbine speed to synchronous speed without the need for operator intervention.

Abstract: A chemical energy power plant includes control of steam temperature to prevent turbine damage while allowing throttling of the power output level and rapid response to commands for changed power output level.

Abstract: In a power plant comprising an evaporator for transferring heat to the working fluid from a heat source whose temperature is subject to variation, thereby evaporating a working fluid, and a turbine driven by the evaporated working fluid, the temperature of the heat source is detected, an optimum physical value relating to the evaporation at the evaporator is caluculated in accordance with the detected temperature, and evaporation of the working fluid at the evaporator is controlled in accordance with the calculated optimum value.

Abstract: A speed feedback loop for load control regulation of a steam turbine. A difference between rated and actual turbine speed results in a speed error to which a deadband function is applied. Operation is such that the deadband, rather than being centered about a fixed value, moves as a function of speed error.

Abstract: A steam turbine plant includes a steam turbine with a shrink-fit type rotor and a gland seal steam supply apparatus that supplies gland seal steam into the gland portion of the steam turbine. The gland seal steam supply apparatus has an evaporator that uses main steam or turbine extraction steam as a heating medium. A steam supply apparatus supplies steam generated within the evaporator into the portions of the turbine which are in danger of developing stress corrosion cracks. The steam supply apparatus includes a pressure reducing apparatus for supplying steam at a reduced pressure into the portions which are in danger of developing stress corrosion cracks. A steam detecting apparatus detects the steam conditions in the rotor as a function of the turbine load and a control apparatus receives the detected signal from the steam detecting apparatus for the purpose of controlling either the pressure of steam generated within the evaporator or the operation of the pressure reducing apparatus.

Abstract: In a steam power plant, a system is provided for early detection of a rupture or extensive leak from the feedwater tubing in the feedwater heaters. The system senses the temperature and pressure in the steam space of each feedwater heater. A pressure rise followed by a temperature drop in the steam space of a feedwater heater is recognized as being caused by a rupture or extensive leak in the feedwater heater and in response to such occurrance, an alarm is activated and a power assisted check valve is closed in the extraction line feeding extraction steam from the turbine to the feedwater heater.

Abstract: A microprocessor-based controller for an extraction type steam turbine-generator unit capable of selecting from a variety of predetermined control strategies and implementing corresponding valve position control loops by generating appropriate valve position control signals in accordance with operator-chosen setpoint signals and turbine operating level signals. In a particular control strategy, automatic compensation of megawatt output is achieved during the extraction mode of turbine operation by summing a megawatt setpoint signal from a feedback loop with a feedforward extraction valve setpoint signal and a megawatt reference signal, which sum is then applied to the turbine control valves to enable tight megawatt control during the extraction operation.

Abstract: An apparatus for controlling an operation of a turbine plant on a reduction of the load on a turbine operates to compute a saturation pressure corresponding to the temperature in the downcomer pipe by using the detected values representing the conditions of the plant, and to control the reduction of the turbine to maintain the pressure in the downcomer pipe higher than the computed saturation pressure so as to prevent an occurrence of flashing.

Abstract: In a combined steam generator-turbine system, a drain type is provided in front of the stop valve to drain the first steam supply with the stop valve closed until the temperature of the valve and/or the temperature of the steam exceeds the temperature of saturation by a predetermined amount, and logic circuitry is provided to generate permissive signals which combine to allow successive admission of steam to the gland seal and to the steam turbine.

Abstract: In a combined cycle steam generation power plant, until steam extraction can be used to reheat the deaerator, the economizer and/or the pegging recirculation are controlled so as to track the pressure upwards of the autocirculation reheater from the low pressure evaporator with a certain lag in pressure, and to establish pressure in the deaerator on the decreasing trend of the autocirculation reheater at a slower rate and without lowering below a minimum pressure so as to prevent the occurrence of bubbling and cavitation effect.

Abstract: Hydraulically operated turbine steam admission valves wherein each valve has its own microcomputer control. In the event the valve gets stuck due to possible contamination in the hydraulic system, the microcomputer control provides an oscillatory control signal to dither the valve. If the valve remains stuck after dithering action it is provided with a control signal of an initial magnitude greater than that normally required to close the valve.

Abstract: A microprocessor-based controller for an extraction type steam turbine-generator unit capable of selecting from a variety of predetermined control strategies and implementing corresponding valve position control loops by generating appropriate valve position control signals in accordance with operator-chosen setpoint signals and turbine operating level signals. The extraction mode of turbine operation is subdivided into a provided set of mutually exclusive extraction control loops, each of which can be placed in service in a bumpless fashion upon transition from any other extraction control loop in a predetermined sequence. Upon a return from the manual mode of turbine operation to the automatic mode, a particular extraction control loop is automatically placed in service without the need for operator intervention.

Abstract: A high pressure steam turbine having a sealing gland where the turbine rotor penetrates the casing of the turbine. Under certain conditions the gland is sealed by an auxiliary steam supply, and under other conditions the gland is self sealed by turbine inlet steam. A control system is provided to modify the temperature of the auxiliary steam to be more compatible with the self sealing steam, so as to eliminate thermal shock to the turbine rotor.

Abstract: A low pressure steam turbine which is subject to an extremely narrow corrosive salt deposition zone includes rotating and stationary blades. One of the stationary blades has an array of sensors thereon divided up into a plurality of rows, one near the tip of the blade, one near the root of the blade and the third intermediate the two. The sensors are of the type which are flexible so as to conform to the curvature of the blade and will provide an output signal indicative of the presence of a salt solution. The outputs from the sensors are analyzed to provide an indication of the location of the salt solution zone.

Abstract: A test apparatus and method tests for closure of ganged, cam operated main control valves in a steam turbine. Cam actuation of a set of upper main control valves is separated from cam actuation of a lower set of main control valves. A test controller actuates one of the sets of main control valves in the opening or closing direction and holds the other set stationary while monitoring turbine power output. When the power output has changed by a predetermined amount, the test controller halts actuation of the first-actuated set of main control valves and begins actuating the other set of main control valves in the opposite direction until the turbine power output has changed a predetermined amount in the opposite direction. The process of incrementally closing one set while incrementally opening the other set of main control valves is continued until the set of main control valves being moved in the closing direction should be fully closed.

Abstract: A variable pressure power cycle and control system that is adjustable to a variable heat source is disclosed. The power cycle adjusts itself to the heat source so that a minimal temperature difference is maintained between the heat source fluid and the power cycle working fluid, thereby substantially matching the thermodynamic envelope of the power cycle to the thermodynamic envelope of the heat source. Adjustments are made by sensing the inlet temperature of the heat source fluid and then setting a superheated vapor temperature and pressure to achieve a minimum temperature difference between the heat source fluid and the working fluid.

Abstract: This invention provides for regulating the generation of a generator at a local power station whose governor receives control signals from a central load dispatcher effective to change the generation so long as there is a change in generation required to meet desired system conditions and wherein a signal representative of actual generation of the generator is fed back to the load dispatchers office. The improvement provides means for producing a signal representative of the ratio of the throttle pressure set point to the actual throttle pressure as well as means for multiplying the signal representative of actual generation by that ratio and supplying the product as the sole feedback to the load dispatcher for determining the control signals to the governor.

Abstract: A combined valve including in combination a stop valve for blocking heating steam introduced into a steam turbine and a control valve assembled in a valve casing in opposed relation. The stop valve is located upstream of the control valve with respect to the stream of the heating steam, and the stop valve and the control valve are each formed in the valve body of a main valve thereof with a bypass valve for allowing the heating steam to flow therethrough. The arrangement enables steam to flow in a volume necessary for starting the steam turbine and allows the limitations placed on the stop valve in opening same to be eliminated.

Abstract: An overspeed detection circuit for producing an overspeed trip signal for shutting off a supply of motive fluid to a prime mover upon the prime mover exceeding an overspeed trip limit includes a differentiating circuit effective to differentiate a speed signal to produce an acceleration signal related to the rate of change in the speed signal. The acceleration signal is summed with the speed signal to produce an effective speed signal which anticipates the crossing of an overspeed threshold when a fault permits a constant speed increase to occur but does not force the summed signal to cross the overspeed threshold when normal speed control is exercised.

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.

Abstract: In a steam turbine used with a power plant operated under variable pressure of the steam which is fed to the turbine through control valves, the control apparatus is arranged to control the control valves according to a signal obtained by adding an opening set signal with a compensation signal which is determined in dependence on a difference between a turbine stage steam pressure signal and a signal derived by multiplying the opening set signal with a ratio of the actual value of the control valve inlet steam pressure to a rated value thereof.

Abstract: A solar pond power plant has a solar pond with a heat storage layer for storing heat absorbed from solar radiation incident on the pond, and a low-temperature, closed Rankine-cycle turbogenerator operating on heat extracted from the heat storage layer. The turbogenerator has a generating capacity of Q.sub.I watts/m.sup.2 of pond area, this capacity being in excess of Q.sub.e watts/m.sup.2 of pond area where Q.sub.e is the net electrical energy that can be generated by the turbogenerator when heat is extracted from the heat storage layer at substantially the same average rate at which heat is absorbed by the layer. According to the invention, the generating capacity Q.sub.I of the turbogenerator is in the range 2-10 times Q.sub.e, whereby the solar pond power plant can be utilized for peak power requirements of a regional electrical generating system.

Abstract: A steam turbine is provided with an electrohydraulic control system having an automatic control which includes a digital computer and further having a manual backup control for operating the turbine on automatic or operator switchover to backup control. The automatic control includes control elements and logic elements associated with valve control loops coupled to the turbine and high and low limits and other constants, setpoints and other parameters are characteristic to these control and logic elements and the interrelations among them and the turbine. A switch arrangement is provided for generating parameter value signals corresponding to changed values for the system parameters and for coupling the parameter value signals to the automatic control system where they are registered. The automatic control system is structured to reject invalid parameter value changes and to register only those parameter value changes which can be validly entered as part of the system structure.