Abstract: A turbine valve control system is provided. The turbine valve control system includes a variable flow metering device, a first sensor, a second sensor, a third sensor, a fourth sensor, memory, and processing circuitry. The variable flow metering device is capable of meeting a plurality of predetermined mass flow rates by varying positioning of the flow metering device. The first sensor is configured for detecting variable positioning of the flow metering device and generating a first output signal that is a function of the positioning of the flow metering device. The second sensor is configured for detecting fluid pressure upstream of the flow metering device and generating a second output signal that is a function of the detected upstream fluid pressure. The third sensor is configured for detecting fluid pressure downstream of the flow metering device and generating a third output signal that is a function of the detected downstream fluid pressure.

Abstract: A method of operating a turboalternator when the turbine engine speed is between synchronous speed and self-sustaining speed.

Abstract: A transient fault detection system and method is provided that facilitates improved fault detection performance in transient conditions. The transient fault detection system provides the ability to detect symptoms of fault in engine that occur in transient conditions. The transient fault detection system includes a feature extractor that measures sensor data during transient conditions and extracts salient features from the measured sensor data. The extracted salient features are passed to a classifier that analyzes the extracted salient features to determine if a fault has occurred during the transient conditions. Detected faults can then be passed to a diagnostic system where they can be passed as appropriate to maintenance personnel.

Abstract: A microprocessor-based control system for a gas turbine electrical powerplant the microprocessor-based control system controls the startup, operation, and shutdown of the gas turbine electric powerplant. The microprocessor-based control system of the present invention dispenses with the need to utilize relays, timers, or other control hardware. Rather, the microprocessor-based control system employs software that replaces the control hardware, and directly reads the inputs, calculates the control actions, and writes the outputs. The microprocessor-based control system is also in electrical communication with an overspeed control system, provided to ensure that a runaway condition of the gas turbine engine does not occur should the gas turbine engine become disconnected from the speed reducer (gearbox) or generator. Sensors are used to monitor multiple operating conditions of the powerplant.

Abstract: A method of operating a turboalternator when the turbine engine speed is between synchronous speed and self-sustaining speed.

Abstract: Maintenance procedures for an article such as a component of a gas turbine engine are analyzed by defining a set of workscopes that may be performed upon the article, gathering maintenance frequency information for each type of subsequent trailing workscope that may be performed after a prior leading workscope, for a sample set of maintenance procedures, and determining a measured sample workscope mix in the form of a set of trailing workscope probabilities as a function of each leading workscope. A projected workscope mix is projected for a set of maintenance procedures from the measured sample workscope mix. From the projected workscope mix, labor, supplies, and monetary estimates for maintenance procedures may be calculated. Alternative maintenance strategies may be readily compared using this approach.

Abstract: A decision making process for evaluating performance shifts identified during a diagnostic trend analysis of gas turbine engine data includes first determining whether each performance shift is actionable, and then determining what maintenance action is required for actionable performance shifts. The maintenance action is determined by identifying potential causes of the actionable performance shifts and ranking the identified potential causes in most likely order. A manual is provided for guiding a user through the decision making process. The manual includes a flow chart flow chart setting forth the steps of the decision making process and a number of tables used in the process.

Abstract: In a control system for a gas turbine aeroengine having a control unit made up of an electronic control unit (ECU) which calculates a fuel flow rate command value based at least on the detected rotational speed of the turbine and the desired power output and a fuel control unit (FCU) including at least a fuel metering valve which meters fuel to be supplied to the engine based on the calculated fuel flow rate command value, the ECU is integrally connected to the FCU, thereby reducing the size and weight of the control units and hence, reducing the occurrence of resonance which would otherwise be likely to occur. In the system, an alternator is integrally connected to the FCU and the rotational speed of the turbine is detected based on the wave form generated by the alternator. Moreover, the ECU calculates the fuel flow rate command value such that the fuel flow rate to be supplied to the engine is brought to a prescribed value. This makes it unnecessary to provide the overspeed protector.

Abstract: At a torque converter characteristic assuming unit, during non gear shift, gear ratio and an input shaft torque are assumed and also during gear shift, accessory torque is assumed. So as to correct the accessory torque a deviation between pump torque and engine torque is learned and this value is given to the accessory torque, thereby the input shaft torque can be executed and assumed. A drive shaft torque is obtained from a drive shaft torque calculating unit, a control period of the drive shaft torque is determined, a reference drive shaft torque is determined during torque control period from a reference drive shaft torque setting unit. A deviation between the reference drive shaft torque and the drive shaft torque is obtained from a torque deviation executing unit. An engine controlling unit varies the engine torque by controlling an ignition period so as to decrease substantially zero the deviation.

Abstract: A horsepower limiting engine control limits the maximum engine horsepower output during operating conditions that might result in torque outputs that are greater than the transmission component ratings. The control includes an electronic controller connected to solenoid driver circuitry, an engine speed sensor and a gear selector. The solenoid driver circuitry energizes a solenoid in response to an engine speed less than a first predetermined engine speed value. The solenoid causes a moveable stop to retract permitting the engine to produce full rated power. The electronic controller causes the solenoid circuitry to de-energize and extend the moveable stop in response to the engine speed exceeding a second predetermined engine speed value and the gear selector being in a predetermined position.