The subject matter of this specification can be embodied in, among other things, a method that includes receiving one or more surge value parameters, selecting a first value from a selected parameter of the one of the parameters, determining a moving average, determining a rate of change, identifying a first phase of a surge cycle based on determining that the rate of change exceeds a threshold rate change, memorializing the first value, the moving average value, and a first time index, receiving a second value of the selected parameter, identifying a second phase of the surge cycle, receiving a third value of the selected parameter, identifying a third phase of the surge cycle, and providing an indication that one or more compressor surge cycles have occurred.

A thrust scheduling method for a gas turbine engine that includes a plurality of blades having a variable pitch beta angle is provided. The method can include receiving into a control system at least one condition input from a respective sensor; receiving into a control system a low pressure shaft speed from a low pressure shaft speed sensor; receiving a control command from a full authority digital engine control (FADEC) in the control system; generating a low pressure shaft speed base reference from a first schedule logic in the control system based upon the at least one condition input received and the control command received; generating a beta angle base reference from a second schedule logic from the at least one condition input received, the low pressure shaft speed, and the control command received; and supplying the low pressure shaft speed base reference and the beta angle base reference to an engine control system, wherein the engine control system adjusts at least the pitch angle of the plurality of fan blades or a fuel flow to the engine.

An anti-surge system capable of anticipating a surge event in a compressor for readying the actuator to quickly actuate the anti-surge valve from the closed position to the open position. The control system includes a compressor surge controller configured to transmit a signal to the valve positioner when the operating point of the valve is approaching the surge control line. The compressor surge controller may monitor an operating margin equal to the difference between the operating point and the surge control line, and when the operating margin falls below a prescribed threshold, the compressor surge controller may send a signal to the positioner. In turn, the positioner may vent some pressure from the actuator. In this way, the dead time of the anti-surge valve on the valve seat is minimized and the valve will react more promptly to an opening signal.

A gas compressing system including a plurality of n compressors connected in parallel. Each compressor has a suction line connected to a common suction manifold and a discharge line connected to a common discharge manifold configured to deliver compressed gas to a downstream load. The system also includes a process controller configured to control an average speed of the compressors based upon a discharge pressure in the common discharge manifold or a discharge flow through the common discharge manifold. The system further includes an adaptive load sharing optimizing controller configured to determine the speed of each compressor in the plurality of n compressors. A method of controlling a gas compressing system is also provided.

A controller for a system having an evaporator, a condenser, and a dynamic compressor includes a processor and a memory, which stores instructions that program the processor to determine a first heat transfer fluid temperature at a first heat transfer fluid path of the evaporator, determine a first pressure at a first working fluid path based on first heat transfer fluid temperature, determine a second heat transfer fluid temperature at a second heat transfer fluid path of the condenser, determine a second pressure at a second working fluid path based on the second heat transfer fluid temperature, calculate an estimated pressure ratio of the compressor from the first and second pressures, determine a speed setpoint of the compressor based on the estimated pressure ratio, and operate the compressor at the speed setpoint to compress a working fluid until a condition is met.

A control device that controls a fuel gas supply system that has: a compressor that supplies compressed fuel gas to a load apparatus; an inflow amount regulating means that regulates the amount of fuel gas that flows into the compressor; an anti-surge valve that is for returning to an inlet side of the compressor fuel gas that is discharged from the compressor; and an inlet pressure-regulating valve that regulates the pressure of fuel gas supplied toward the inflow amount regulating means. The control device includes: a main pressure-regulating unit that controls the inflow amount regulating means and the anti-surge valve using a first feedforward control value that is generated on the basis of the load of the load apparatus and of a first conversion process and using a feedback control value that is generated on the basis of the deviation between a set value and a measured value for the discharge pressure of the compressor; and an inlet pressure-regulating unit that controls the inlet pressure-regulating valve using a second feedforward control value that is generated on the basis of the load of the load apparatus and of a second conversion process.

A measurement method for a steam valve according to at least one embodiment of the present disclosure, includes: a step of measuring acceleration of a valve stem when a slave valve is opened by driving the valve stem with an actuator from a fully closed state of a master valve and the slave valve; a step of detecting a timing at which the slave valve is fully opened, based on the measured acceleration of the valve stem; and a step of calculating an amount of movement of the valve stem from a reference position to a position where the slave valve is fully opened.

A fuel supply line system used for a gas turbine, including: fuel gas control valves used for controlling delivery to the gas turbine; a first line used for connecting the fuel gas source to the control valves; a second line used for connecting the control valves to the gas turbine; a monitoring device, configured to be used for determining the pressure inside the pipe at the outlet of the second line near said control valve; and a controller, configured to reduce the effective flow area of the pressure control valves or close the control valves when the determined pressure inside the pipe of the second line is greater than a predetermined pressure.

The subject matter of this specification can be embodied in, among other things, a method that includes receiving one or more surge value parameters, selecting a first value from a selected parameter of the one of the parameters, determining a moving average, determining a rate of change, identifying a first phase of a surge cycle based on determining that the rate of change exceeds a threshold rate change, memorializing the first value, the moving average value, and a first time index, receiving a second value of the selected parameter, identifying a second phase of the surge cycle, receiving a third value of the selected parameter, identifying a third phase of the surge cycle, and providing an indication that one or more compressor surge cycles have occurred.

A steam valve according to at least one embodiment of the present disclosure, includes: a valve body that includes a steam flow path through which steam flows, and a valve seat disposed in the middle of the steam flow path and having an opening portion; and a stop valve that includes a valve stem which extends in an axial direction, where an axis extends, and is movable back and forth in the axial direction, and a first valve disc which is fixed to a distal end part of the valve stem and is abutted against the valve seat to close the steam flow path. The valve stem is partitioned into a first valve stem to which the first valve disc is fixed and a second valve stem different from the first valve stem.