Abstract: Oil system components for a turbine engine are used to provide a vacuum system for a fuel stabilization unit (FSU). A vacuum system pulls oxygen and other contaminants from fuel into a vacuum chamber within the FSU. The vacuum system pumps the discharge through a vacuum outlet in the FSU toward a vacuum pump. Due to the quality of vacuum required, a two-stage vacuum pump is used. A first stage vacuum pump is an oil system scavenge pump for the turbine engine and the second stage vacuum is provided by a second stage vacuum pump. The discharge flows from the vacuum chamber through to the second stage vacuum pump and is then added to the oil supply. The oil and discharge mixture is sent through an oil system de-oiler and a de-aerator to clean the oil supply prior to pumping the oil back through the oil system.

Abstract: A fuel system includes a turbine engine, and an electric motor that are independently drivable relative to one another. The electric motor has a speed that is selectively controlled based upon a desired fuel flow. A centrifugal pump is driven by the turbine engine. The centrifugal pump provides a desired fuel pressure for the fuel system. A positive displacement pump is driven by the electric motor The positive displacement pump is in fluid communication with the centrifugal pump, for example in a series arrangement. The positive displacement pump meters a desired volume in response to the speed of the second drive assembly.

Abstract: A turbine engine inspection arrangement utilizes a motor that is otherwise utilized for starting the engine. An inspection interface allows for communicating with a motor controller to operate the motor in an inspection mode. During inspection, the motor moves the components of the engine very slowly or in an incremental fashion to facilitate visual inspection of the engine components, such as the turbine blades.

Abstract: A fuel system includes a turbine engine, and an electric motor that are independently drivable relative to one another. The electric motor has a speed that is selectively controlled based upon a desired fuel flow. A centrifugal pump is driven by the turbine engine. The centrifugal pump provides a desired fuel pressure for the fuel system. A positive displacement pump is driven by the electric motor The positive displacement pump is in fluid communication with the centrifugal pump, for example in a series arrangement. The positive displacement pump meters a desired volume in response to the speed of the second drive assembly.

Abstract: An electric start system (20) includes a controller (40) that controls operation of a motor (22) used to start a device such as a gas turbine engine (24). In one example, the controller (40) determines when an acceleration rate of the motor (22) is outside of a desired range and dynamically controls the acceleration rate. In another example, the controller (40) determines when the motor (22) is disengaged from the engine (24) and controls a torque reference value to facilitate smoother reengagement. In another example, the controller (40) provides an initial starting torque value that allows for soft starting capabilities of the motor (22).

Abstract: A turbine engine inspection arrangement utilizes a motor that is otherwise utilized for starting the engine. An inspection interface allows for communicating with a motor controller to operate the motor in an inspection mode. During inspection, the motor moves the components of the engine very slowly or in an incremental fashion to facilitate visual inspection of the engine components, such as the turbine blades.

Abstract: An integrated skid system integrates the functions of multiple skids into a single skid to reduce the skid footprint and the complexity of the overall system. A multi-motor controller monitors the devices on the integrated skid to maintain proper temperature, pressure and current draw in the devices. Base on this information, the multi-motor controller can make decisions on faults and fault accommodation and communicate with a main controller regarding the operating states of the skid devices via a single serial or Ethernet-type connection.

Abstract: An electric engine starting system includes a permanent magnet motor that is used to start the engine and then to generate power for powering a load while the engine is running. A disclosed system includes a first phase controlled rectifier in series with a power converter and a second phase controlled rectifier. During an engine starting operation, the first phase controlled rectifier is switched to couple the permanent magnet motor to a power source for starting the engine. Once the engine is running, the first phase controlled rectifier is switched off and the second phase controlled rectifier is switched on. The second phase control rectifier converts variable AC power from the motor into DC power. The power converter converts the DC power into an appropriate power for driving the load. One disclosed example includes a filter between the power converter and the load to ensure that the load receives a selected quality of power.

Abstract: An electric motor has at least one component that is submerged in a cooling fluid held in a fluid-filled cavity. The stator, rotor, and rotor shaft bearings are all possible components that may be submerged. The cooling fluid floods the stator, rotor, and/or bearings to cool the components. The fluid may have a high electrical resistance to isolate the motor components from any contact with flammable gasses as well as prevent arcs or sparks. The cavity holding the fluid also ensures continuous lubrication by preventing fluid from leaking or evaporating out of the motor.

Abstract: A fluid scavenging system is provided for a lubrication system including a gas turbine engine having bearing compartments. A valve includes a housing with an outlet and a plurality of fluid inlets respectively in fluid communication with the bearing compartments. The valve includes a rotationally driven member arranged within the housing with the member having a plurality of ports arranged thereon each defining an arcuate slot. Each of the ports are selectively in fluid communication with one of the fluid inlets through the arcuate slot during rotation of the member for selectively permitting fluid flow between the opening of one of the fluid inlets through one of the corresponding ports in the member. A fluid pump is fluidly connected to the outlet for drawing fluid from each of the plurality of fluid compartments during fluid rotation of the member.

Abstract: A fuel supply control system for a gas turbine includes a plurality of solenoid valves. The solenoid valves are energized in a timing sequence with a phase relationship designed to achieve a desired fuel flow. In one example, one solenoid valve is associated with a primary portion of a fuel manifold while at least two other solenoids are associated with a secondary portion of the manifold. A controller that energizes the solenoids to achieve the desired fuel flow can receive feedback information regarding turbine performance to make adjustments to the solenoid operation to bring the turbine performance closer to a desired level.

Abstract: A fluid scavenging system is provided for a lubrication system including a gas turbine engine having bearing compartments. A valve includes a housing with an outlet and a plurality of fluid inlets respectively in fluid communication with the bearing compartments. The valve includes a rotationally driven member arranged within the housing with the member having a plurality of ports arranged thereon each defining an arcuate slot. Each of the ports are selectively in fluid communication with one of the fluid inlets through the arcuate slot during rotation of the member for selectively permitting fluid flow between the opening of one of the fluid inlets through one of the corresponding ports in the member. A fluid pump is fluidly connected to the outlet for drawing fluid from each of the plurality of fluid compartments during fluid rotation of the member.

Abstract: The present invention provides a fuel system for an engine including a water supply source for providing water and a fuel supply source for providing fuel. A centrifugal pump is fluidly connected to the water and fuel supply sources, respectively at water and fuel inputs. The pump receives the water and the fuel from the inputs and produces a homogeneous mixture without using other pumps or mixing devices. A metering device is arranged between the pump and one of the supply sources, preferably the water supply source, to produce the desired ratio of water and fuel. The speed of the pump is varied to deliver the desired total volume and pressure of fuel and water to the engine through the pump output. The water metering device may be closed to deliver only fuel to the engine during special conditions such as engine startup and rapid load dumps. Operation of the system is simplified because only one pump and metering device is used.

Abstract: A fuel supply control system for a gas turbine includes a plurality of solenoid valves. The solenoid valves are energized in a timing sequence with a phase relationship designed to achieve a desired fuel flow. In one example, one solenoid valve is associated with a primary portion of a fuel manifold while at least two other solenoids are associated with a secondary portion of the manifold. A controller that energizes the solenoids to achieve the desired fuel flow can receive feedback information regarding turbine performance to make adjustments to the solenoid operation to bring the turbine performance closer to a desired level.

Abstract: A engine control system for helicopters and the like in which free turbine speed is isochronously controlled by a more robust control system having increased bandwidth due to loop architecture and filter implementation accomplished via closed loop control. Dual notch (feedback compensation) is used with design forward path compensation, including variable lead/position of the lead, variable gain and implementation of integrator/proportional. Superior transient control is achieved by the use of a multi-loop governing design using different error compensations when on "NF" loop control and when not on "NF" loop control, and with "bumpless" inner loop reference by the combination of compensation switching and re-initialization of a common integrator. Parallel select logic with dynamic compensation is used separating the system control loops and the selection process of the controlling functions, as they pertain to the application of control loops designed form small signal stability to large transients.

Abstract: A engine control system for helicopters and the like in which free turbine speed is isochronously controlled by a more robust control system having increased bandwidth due to loop architecture and filter implementation accomplished via closed loop control. Dual notch (feedback compensation) is used with design forward path compensation, including variable lead/position of the lead, variable gain and implementation of integrator/proportional. Superior transient control is achieved by the use of a multi-loop governing design using different error compensations when on "NF" loop control and when not on "NF" loop control, and with "bumpless" inner loop reference by the combination of compensation switching and re-initialization of a common integrator. Parallel select logic with dynamic compensation is used separating the system control loops and the selection process of the controlling functions, as they pertain to the application of control loops designed form small signal stability to large transients.

Abstract: Parameters indicative of gas turbine engine operational characteristics are sensed and the signals processed to derive further operational characteristic information therefrom, each information signal being compared in a subroutine to a corresponding threshold signal for exceedence thereof, the magnitude of each threshold signal being indicative of incipiency of compressor stall, a counter being incremented in the subroutine upon any threshold exceedence occurrence, the amount of counter increment depending on the ability of each information signal to predict the incipiency of stall, the higher the counter value the greater the stall incipiency. The counter is decremented during each subroutine execution, the counter value during the current subroutine execution being compared to that of the previous subroutine execution to determine the direction of stall incipiency. The counter is utilized as a bias signal to an engine acceleration schedule to vary the rate of acceleration as the counter is varied.

Abstract: The existence of autorotation of a load (e.g., a helicopter rotor system) coupled to the free turbine of a gas turbine engine is determined and a signal indicative thereof enables an integrator which, upon autorotation, integrates rate-based recovery anticipation provided thereto, the integrator output providing a time-composite bias signal to the main control portion of the engine fuel control to increase the speed of the gas generator of the engine in anticipation of rotor reengagement with the free turbine. The amount of recovery error is determined from the rotor speed error and is multiplied with the integrator output, the product being fed, upon completion of autorotation recovery, to the integrator input whose output now provides a controlled removal of the bias signal from the main control portion so as to minimize transients induced therein.

Abstract: The speed of the gas generator of a gas turbine engine is measured and summed with the rate of change of the gas generator speed and the sum is input to a schedule which outputs desired engine acceleration as a function of gas generator speed, the input thereby providing an anticipation to the schedule output so as to result in a dynamic shift of the schedule. In an exemplary embodiment of the invention in a helicopter fuel control, the amount of anticipation provided by the schedule input allows the fuel control to accurately control the engine to the desired acceleration schedule.