Abstract: In a temperature estimation apparatus for an aeroplane gas turbine engine, there are provided with a calculator that calculates a low-pressure turbine outlet temperature change (dEGT) based on low-pressure turbine rotational speed (N1) and ambient temperature (T1), a calculator that calculates a model outlet temperature (MODEL-EGTC) based on corrected high-pressure turbine rotational speed (N2C) and atmospheric pressure (P0) to calculate a model outlet temperature difference (dEGTC) by subtracting the calculated temperature (MODEL-EGTC) from a corrected low-pressure turbine outlet temperature (EGTC), a calculator that calculates a correction amount (dEGTad) relative to the model outlet temperature difference (dEGTC) based on the model outlet temperature difference (dEGTC) and low-pressure turbine rotational speed (N1), and a calculator that calculates an estimation value of the low-pressure turbine inlet temperature (ITT) based on the low-pressure turbine outlet temperature (EGT), etc.

Abstract: In a temperature estimation apparatus for an aeroplane gas turbine engine mounted on an aircraft and having a combustion chamber, a high-pressure turbine rotated by combustion gas exhausted from the combustion chamber, a low-pressure turbine located downstream of the high-pressure turbine to be rotated by low-pressure gas which has passed through the high-pressure turbine, a high-pressure turbine rotational speed sensor, a low-pressure turbine rotational speed sensor, and a temperature sensor, inlet temperature at an inlet of the high-pressure turbine is estimated based on the detected outlet temperature of the low-pressure turbine and the rotational speed of the low-pressure turbine and is corrected with the detected rotational speed of the high-pressure turbine.

Abstract: In a temperature estimation apparatus for an aeroplane gas turbine engine, there are provided with a calculator that calculates a low-pressure turbine outlet temperature change (dEGT) based on low-pressure turbine rotational speed (N1) and ambient temperature (T1), a calculator that calculates a model outlet temperature (MODEL-EGTC) based on corrected high-pressure turbine rotational speed (N2C) and atmospheric pressure (P0) to calculate a model outlet temperature difference (dEGTC) by subtracting the calculated temperature (MODEL-EGTC) from a corrected low-pressure turbine outlet temperature (EGTC), a calculator that calculates a correction amount (dEGTad) relative to the model outlet temperature difference (dEGTC) based on the model outlet temperature difference (dEGTC) and low-pressure turbine rotational speed (N1), and a calculator that calculates an estimation value of the low-pressure turbine inlet temperature (ITT) based on the low-pressure turbine outlet temperature (EGT), etc.

Abstract: In a system for monitoring an output of a sensor for detecting an operating state of a gas turbine engine by comparing a value of an output of the sensor with a prescribed reference value, a calibration map for converting the output of the sensor into a variable that is normally used for controlling the engine is used for defining the reference value for determining the state of the sensor. Thereby, a fault of a sensor can be detected both accurately and promptly by using the existing resource without unduly complicating the control program. It is particularly desirable to monitor the output of the sensor by taking into account the current operating condition of the engine to improve the reliability in detecting a fault in the sensor.

Abstract: In a temperature estimation apparatus for an aeroplane gas turbine engine mounted on an aircraft and having a combustion chamber, a high-pressure turbine rotated by combustion gas exhausted from the combustion chamber, a low-pressure turbine located downstream of the high-pressure turbine to be rotated by low-pressure gas which has passed through the high-pressure turbine, a high-pressure turbine rotational speed sensor, a low-pressure turbine rotational speed sensor, and a temperature sensor, inlet temperature at an inlet of the high-pressure turbine is estimated based on the detected outlet temperature of the low-pressure turbine and the rotational speed of the low-pressure turbine and is corrected with the detected rotational speed of the high-pressure turbine.

Abstract: In a system for monitoring an output of a sensor for detecting an operating state of a gas turbine engine by comparing a value of an output of the sensor with a prescribed reference value, a calibration map for converting the output of the sensor into a variable that is normally used for controlling the engine is used for defining the reference value for determining the state of the sensor. Thereby, a fault of a sensor can be detected both accurately and promptly by using the existing resource without unduly complicating the control program. It is particularly desirable to monitor the output of the sensor by taking into account the current operating condition of the engine to improve the reliability in detecting a fault in the sensor.

Abstract: In a gas turbine aeroengine control system, in Ch-A (first control channel), a first CPU monitors the operation of a second CPU and the second CPU monitors the operation of the first CPU; in Ch-B (second control channel), third and fourth CPUs similarly monitor each other, and when the operation of at least one of the first and second CPUs in Ch-A is found not to be normal, the output sent to an FCU (fuel control unit) is switched from the output of one or the other of the first and second CPUs of Ch-A to the output of one or the other of the third and fourth CPUs of Ch-B, thereby achieving improved CPU failure detection and realizing high redundancy and high reliability.

Abstract: In a system for monitoring an output of a sensor for detecting an operating state of a gas turbine engine by comparing a value of an output of the sensor with a prescribed reference value, a calibration map for converting the output of the sensor into a variable that is normally used for controlling the engine is used for defining the reference value for determining the state of the sensor. Thereby, a fault of a sensor can be detected both accurately and promptly by using the existing resource without unduly complicating the control program. It is particularly desirable to monitor the output of the sensor by taking into account the current operating condition of the engine to improve the reliability in detecting a fault in the sensor.

Abstract: In a gas-turbine engine control system having a first control channel inputting the outputs of sensors to calculate and output a first command value indicative of a quantity of fuel to be supplied to the engine and a second control channel inputting the outputs of the sensors to calculate and output a second command value similarly indicative of the quantity of fuel, the second control channel calculates and outputs the second command value using the first command value so long as the instruction to switch the outputs is not generated, while calculates and outputs the second command value, without using the first command value, when the instruction to switch the outputs is generated. With this, immediately after switching to the second command value, the second command value is made substantially equal to and not greatly different from the preceding first command value.

Abstract: In a control system for a gas turbine engine that uses the outlet pressure of the turbine as an importation control parameter, when the high pressure sensor for detecting the outlet pressure of the turbine is found to be faulty, it is determined if an estimated value of the outlet pressure of the compressor is normal or not, and substitute the output value of the high pressure sensor with the estimated value if the estimated value is normal and with the inlet pressure of the fan or a value proportional thereto if the estimated value is not normal. Thereby, the control system is given with such a substitute value for the output of the high pressure sensor in case of a failure of the high pressure sensor that would prevent any abrupt changes in the behavior of the engine and allow the engine to be operated in a stable manner.

Abstract: In the gas-turbine engine control system having first and second control channels each inputting the outputs of speed sensors and controlling supply of fuel to the engine based on the inputted outputs, four outputs generated by the sensors are compared with each other to determine whether three of the four outputs are within a range that allows the three to be considered identical, and the three are then compared with a remaining one to determine whether the four outputs are within the range that allows the three to be considered identical to the remaining one, and based thereon, each of the four outputs is determined to be the output that is usable in the fuel supply control. With this, through the three-value comparison and the four-value comparison, when the high-pressure turbine speed sensor or the like is installed by plural numbers, it becomes possible to accurately select the sensor output(s) that is usable in the fuel supply control, thereby improving the control accuracy.

Abstract: The sensor malfunction detection system for a gas-turbine engine is configured to determine or check once every first predetermined time period whether the outputted value from the sensor is within a permissible range and determines that the sensor is faulty when the result of the check is at least one result between the case of the number of times the outputted value is found not to be within the permissible range exceeding a first predetermined value and the case of the number of times the outputted value is consecutively found not to be within the permissible range exceeding a second predetermined value.

Abstract: In the gas-turbine engine control system having a first control inputting the outputs of sensors and controlling supply of fuel to the engine based on at least one of the inputted outputs, the first control channel includes a comparator inputting the outputs generated by the sensors and comparing change rates of the outputs with corresponding threshold values once every predetermined time period, and a transient/steady-state discriminator discriminating that the engine is in a transient state when the number of the outputs found to be equal to or greater than the corresponding threshold values are equal to or greater than a predetermined value, while discriminating that the engine is in a steady state when the number of times that the outputs are found to be smaller than the threshold values is more than half of number of comparison time.

Abstract: In a control system for a gas turbine engine that uses the outlet pressure of the turbine as an importation control parameter, when the high pressure sensor for detecting the outlet pressure of the turbine is found to be faulty, it is determined if an estimated value of the outlet pressure of the compressor is normal or not, and substitute the output value of the high pressure sensor with the estimated value if the estimated value is normal and with the inlet pressure of the fan or a value proportional thereto if the estimated value is not normal. Thereby, the control system is given with such a substitute value for the output of the high pressure sensor in case of a failure of the high pressure sensor that would prevent any abrupt changes in the behavior of the engine and allow the engine to be operated in a stable manner.

Abstract: In a gas turbine aeroengine control system, in Ch-A (first control channel), a first CPU monitors the operation of a second CPU and the second CPU monitors the operation of the first CPU; in Ch-B (second control channel), third and fourth CPUs similarly monitor each other, and when the operation of at least one of the first and second CPUs in Ch-A is found not to be normal, the output sent to an FCU (fuel control unit) is switched from the output of one or the other of the first and second CPUs of Ch-A to the output of one or the other of the third and fourth CPUs of Ch-B, thereby achieving improved CPU failure detection and realizing high redundancy and high reliability.

Abstract: In a system for monitoring an output of a sensor for detecting an operating state of a gas turbine engine by comparing a value of an output of the sensor with a prescribed reference value, a calibration map for converting the output of the sensor into a variable that is normally used for controlling the engine is used for defining the reference value for determining the state of the sensor. Thereby, a fault of a sensor can be detected both accurately and promptly by using the existing resource without unduly complicating the control program. It is particularly desirable to monitor the output of the sensor by taking into account the current operating condition of the engine to improve the reliability in detecting a fault in the sensor.

Abstract: In a gas-turbine engine control system having a first control channel inputting the outputs of sensors to calculate and output a first command value indicative of a quantity of fuel to be supplied to the engine and a second control channel inputting the outputs of the sensors to calculate and output a second command value similarly indicative of the quantity of fuel, the second control channel calculates and outputs the second command value using the first command value so long as the instruction to switch the outputs is not generated, while calculates and outputs the second command value, without using the first command value, when the instruction to switch the outputs is generated. With this, immediately after switching to the second command value, the second command value is made substantially equal to and not greatly different from the preceding first command value.

Abstract: In the gas-turbine engine control system having first and second control channels each inputting the outputs of speed sensors and controlling supply of fuel to the engine based on the inputted outputs, four outputs generated by the sensors are compared with each other to determine whether three of the four outputs are within a range that allows the three to be considered identical, and the three are then compared with a remaining one to determine whether the four outputs are within the range that allows the three to be considered identical to the remaining one, and based thereon, each of the four outputs is determined to be the output that is usable in the fuel supply control. With this, through the three-value comparison and the four-value comparison, when the high-pressure turbine speed sensor or the like is installed by plural numbers, it becomes possible to accurately select the sensor output(s) that is usable in the fuel supply control, thereby improving the control accuracy.

Abstract: The sensor malfunction detection system for a gas-turbine engine is configured to determine or check once every first predetermined time period whether the outputted value from the sensor is within a permissible range and determines that the sensor is faulty when the result of the check is at least one result between the case of the number of times the outputted value is found not to be within the permissible range exceeding a first predetermined value and the case of the number of times the outputted value is consecutively found not to be within the permissible range exceeding a second predetermined value.

Abstract: In the gas-turbine engine control system having a first control inputting the outputs of sensors and controlling supply of fuel to the engine based on at least one of the inputted outputs, the first control channel includes a comparator inputting the outputs generated by the sensors and comparing change rates of the outputs with corresponding threshold values once every predetermined time period, and a transient/steady-state discriminator discriminating that the engine is in a transient state when the number of the outputs found to be equal to or greater than the corresponding threshold values are equal to or greater than a predetermined value, while discriminating that the engine is in a steady state when the number of times that the outputs are found to be smaller than the threshold values is more than half of number of comparison time.