Abstract: A system and method of estimating the torque value of an engine are provided. The method includes generating corrected variable values from engine measured parameters and using a plurality of steady state tables that output corrected engine torque estimates based on various corrected variable values as inputs. In a preferred embodiment, the method also includes a phase compensation technique that converts each steady state table torque estimate into a dynamic torque estimate that closely matches the torque sensor measurements during both transient and steady state engine operations. In addition, also in a preferred embodiment, the method further includes a weighted averaging scheme that combines multiple torque estimates with weighting factors that are optimized based on the accuracy attributes of each torque estimate.

Abstract: A system and method of estimating the torque value of an engine are provided. The method includes generating corrected variable values from engine measured parameters and using a plurality of steady state tables that output corrected engine torque estimates based on various corrected variable values as inputs. In a preferred embodiment, the method also includes a phase compensation technique that converts each steady state table torque estimate into a dynamic torque estimate that closely matches the torque sensor measurements during both transient and steady state engine operations. In addition, also in a preferred embodiment, the method further includes a weighted averaging scheme that combines multiple torque estimates with weighting factors that are optimized based on the accuracy attributes of each torque estimate.

Abstract: A method and a system is provided, useable in electrical control sensors for shaft speed signal frequency change rate tests, detecting intermittent or “in-range”failures. The method estimates a short-term variance of the measured signal or signal rate of change, using the equation: Var[x]=E[x2]?E2[x], where E[x2] is an estimated average of the squared measured signal or rate of change over the short term, and E2[x] is a squared estimated average of the measured signal or rate of change over the short term. The estimated variance is compared with a predefined variance limit for a predefined amount of time, and if the estimated variance exceeds the predefined variance limit for the predefined amount of time, the measured signal is deemed invalid. A latching counter is used for timing, and its time out rate is preferably proportional to the time period the measured input is true. The step for estimating a short-term variance of the measured signal uses several filters performing averaging function.

Abstract: A method and a system is provided, useable in electrical control sensors for shaft speed signal frequency change rate tests, detecting intermittent or “in-range” failures. The method estimates a short-term variance (standard deviation) of the measured signal or signal rate of change, using the equation: Var[x]=E[x2]−E2[x], where E[x2] is an estimated average of the squared measured signal or rate of change over the short term, and E2[x] is a squared estimated average of the measured signal or rate of change over the short term. The estimated variance is compared with a predefined variance limit for a predefined amount of time, and if the estimated variance exceeds the predefined variance limit for the predefined amount of time, the measured signal is deemed invalid. A latching counter is used for timing, and its time out rate is preferably proportional to the time period the measured input is true.

Abstract: Improved methods and systems are provided for detecting surge bleed valve faults and analyzing the performance of surge bleed valves in gas turbines. The method includes monitoring the rates of rotation of an engine fan and an engine gas generator in a gas turbine engine. While so doing, a valve status change signal is transmitted to a surge bleed valve in the gas turbine engine. The difference between the two monitored rates of rotation is determined. A surge bleed valve fault signal is generated if the difference between the two monitored rates of rotation does not change by at least a predetermined amount immediately following transmission of the valve status change signal to the surge bleed valve.

Abstract: Improved methods and systems are provided for detecting surge bleed valve faults and analyzing the performance of surge bleed valves in gas turbines. The method includes monitoring the rates of rotation of an engine fan and an engine gas generator in a gas turbine engine. While so doing, a valve status change signal is transmitted to a surge bleed valve in the gas turbine engine. The difference between the two monitored rates of rotation is determined. A surge bleed valve fault signal is generated if the difference between the two monitored rates of rotation does not change by at least a predetermined amount immediately following transmission of the valve status change signal to the surge bleed valve.

Abstract: A method and a system is provided, useable in electrical control sensors for shaft speed signal frequency change rate tests, detecting intermittent or “in-range” failures. The method estimates a short-term variance (standard deviation) of the measured signal or signal rate of change, using the equation: Var[x]=E[x2]−E2[x], where E[x2] is ] is an estimated average of the squared measured signal or rate of change over the short term, and E2[x] is a squared estimated average of the measured signal or rate of change over the short term. The estimated variance is compared with a predefined variance limit for a predefined amount of time, and if the estimated variance exceeds the predefined variance limit for the predefined amount of time, the measured signal is deemed invalid. A latching counter is used for timing, and its time out rate is preferably proportional to the time period the measured input is true.