A turboexpander and driven turbomachine system comprising a turboexpander configured for expanding a first fluid and comprising an expander stage with one expander impeller; a first set of moveable inlet guide vanes at the inlet of the expander stage; a driven turbomachine configured for processing a second fluid and comprising a turbomachine impeller; a second set of moveable inlet guide vanes at the inlet of the turbomachine impeller; a mechanical transmission between the turboexpander and the driven turbomachine; and a controller connected to the second set of moveable inlet guide vanes and configured for controlling the second set of moveable inlet guide vanes for adjusting the rotary speed of the driven turbomachine and said turboexpander.

Herein provided are methods and systems for controlling an engine having a variable geometry mechanism. A pressure ratio between a first pressure at an inlet of the engine and a predetermined reference pressure is determined. An output power for the engine is determined. The output power is adjusted based at least in part on the pressure ratio to obtain a corrected output power. A position control signal for a variable geometry mechanism of the engine is generated based on the corrected output power and the pressure ratio. The position control signal is output to a controller of the engine to control the variable geometry mechanism.

The present invention is directed to a direct-drive fan system and a variable process control system for efficiently managing the operation of fans in a cooling system such as a wet-cooling tower or air-cooled heat exchanger (ACHE), HVAC systems, mechanical towers or chiller systems. The present invention is based on the integration of key features and characteristics such as tower thermal performance, fan speed and airflow, motor torque, fan pitch, fan speed, fan aerodynamic properties, and pump flow. The variable process control system processes feedback signals from multiple locations in order control a high torque, variable speed, permanent magnet motor to drive the fan. Such feedback signals represent certain operating conditions including motor temperature, basin temperature, vibrations, and pump flow rates. Other data processed by the variable process control system in order to control the motor include turbine back pressure set-point, condenser temperature set-point and plant part-load setting. The variable process control system processes this data and the aforesaid feedback signals to optimize the operation of the cooling system in order to prevent disruption of the industrial process and prevent equipment (turbine) failure or trip. The variable process control system alerts the operators for the need to conduct maintenance actions to remedy deficient operating conditions such as condenser fouling. The variable process control system increases cooling for cracking crude and also adjusts the motor RPM, and hence the fan RPM, accordingly during plant part-load conditions in order to save energy.

A method includes obtaining a steady state model that models a process controlled by a controller of a gas turbine. The steady state model estimates at least one output of the process based on at least one input. The method includes creating a transient model by perturbing at least one input of the steady state model to estimate the at least one output, the at least one output comprising transient characteristics of the gas turbine. The method includes adjusting a gain of the controller continuously, at predetermined intervals, or based on a requirement trigger, or any combination thereof, based on the transient model. The gain defines a response to a difference between a reference signal and a feedback signal of the controller of the gas turbine. The method includes sending the adjusted gain to the controller. The controller controls the process based on the adjusted gain.

A method of operating a compression system includes determining, by a controller, at least one of an operational point distance to surge and a surge margin based upon at least one of an electrical power consumed by a compressor and an electrical current consumed by the compressor, and at least one thermodynamic state measurement associated with the compressor.

A steam turbine include a steam chest casing that is provided with a plurality of nozzle openings along a circumferential direction; a partition wall to partition the steam chest casing into the main steam chest and a sub-steam chest with smaller capacity than the main steam chest; a main steam pipe that supplies steam to the main steam chest; a steam chest connection pipe that distributes part of the steam, which is supplied to the main steam chest, to the sub-steam chest; a steam chest connection valve; a pressure gauge that measures the pressure of the steam flowing in the main steam pipe; and a control unit that closes the steam chest connection valve when the measured pressure is less than more than or equal to a predetermined threshold value, and opens the steam chest connection valve when the measured pressure is less than the predetermined threshold value.

The present invention provides a gear pump having one or more gears with bearing shafts supported by respective pressure-loaded gear pump bearing blocks. Each pressure-loaded bearing block has: a bore adapted to receive the bearing shaft of a gear of the pump; a thrust face at one end adapted to slidingly engage with a side surface of the gear, and an opposing rear face at the other end, the pump being adapted such that, in use, pressurised fluid is supplied to the rear face to provide a hydraulic load urging the thrust face of the bearing block towards the side surface of the gear; and a seal carried by the rear face, the seal, in use, partitioning higher fluid pressure and lower fluid pressure portions of the rear face. The gear pump further has a pressure regulating valve arranged such that, in use, the fluid pressure difference between the higher and lower fluid pressure portions of the rear face of the bearing block is adjustable by the valve to vary said hydraulic load.

A compressor surge avoidance control system and method for a gas turbine engine includes sensing a plurality of engine inlet parameters, and receiving a fuel command value. The sensed parameters are processed to determine a surge fuel value that is representative of a fuel flow above which, for the sensed engine inlet parameters, a compressor surge will likely occur. The surge fuel value and the fuel command value are compared, and a protective action signal is generated if the fuel command value exceeds the surge fuel value.

Systems and methods for adjusting airflow distortion in a gas turbine engine using a secondary airflow passage assembly are disclosed. A gas turbine engine can include a compressor section, a combustion section, and a turbine section in series flow and defining at least in part an engine airflow path. A casing can enclose the gas turbine engine and be at least partially exposed to a bypass airflow. The gas turbine engine can further include a secondary airflow passage assembly comprising a door and a duct, the duct defining an inlet located on the casing, the duct defining an outlet in airflow communication with the engine airflow path, the duct comprising an airflow passage extending between the inlet and outlet. The door can be moveable between an open and closed position to allow a portion of the bypass airflow to flow through the airflow passage to adjust airflow distortion.

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.