JP2006063975A - Sensor output monitoring device for gas turbine engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sensor output monitoring device for a gas turbine engine without complicated control program configuration, for correctly and quickly determining adequacy of a sensor output depending on an engine operational status. <P>SOLUTION: The sensor output monitoring device for a gas turbine engine determines the adequacy of the sensor output for acquiring environmental information on the inside and outside of an engine, by comparing the sensor output with a predetermined reference value. A calibration value map is provided to acquire a parameter used for an engine control by corresponding to the sensor output, and the reference value for adequacy determination of the sensor output is set to the calibration map. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a sensor output monitoring device for quickly detecting abnormality of various sensors that acquire information inside and outside a gas turbine engine.

  In an aircraft gas turbine engine, information from various sensors is used to optimally control the operating state of the engine. However, if the sensor fails, the control parameters become abnormal and hinder proper engine control. Therefore, countermeasures for sensor failures are extremely important.

As a sensor failure detection method, a method is known in which the sensor output value exceeds a predetermined limit value or the output change rate exceeds a predetermined value (Patent Document 1). See).
JP-A-6-264767

  However, the technique described in the above-mentioned document is exclusively intended for detection of ignition at the time of starting, and is actually not necessarily suitable for prompt determination of sensor abnormality in a normal operation region or a transient state. In addition, in order to determine the suitability of a plurality of sensor outputs depending on the driving state, it is necessary to prepare as many suitability judgment reference value maps as the number of sensors set corresponding to the difference in the driving state. The configuration of the control program tends to be complicated.

  In view of such inconveniences of the prior art, the present invention does not complicate the configuration of the control program, and can more accurately and promptly determine whether the sensor output is appropriate according to the operating state of the engine. Another object of the present invention is to provide a sensor output monitoring device for a gas turbine engine that can be used.

  In order to solve such a problem, claim 1 of the present invention compares the output of a sensor for acquiring environmental information inside and outside the engine with a predetermined reference value to determine whether the sensor output is appropriate. A gas turbine engine sensor output monitoring apparatus comprising a calibration value map for determining a parameter used for engine control in association with a sensor output, and a reference value for determining whether the sensor output is appropriate or not. It was set as the characteristic. In particular, a plurality of the reference values are set corresponding to the difference in the driving state, and a value suitable for the driving state at that time is selected (Claim 2), or a discrimination value for discriminating the driving state of the engine May be set in the calibration value map (claim 3).

  According to the present invention as described above, it is possible to set the appropriateness determination reference value of the sensor and the engine operating state determination value in the parameter map used for normal engine control. There is no need to separately set a value map or a discriminant value map only for discriminating the operating state of the engine, and a great effect can be achieved in simplifying the configuration of the control program. In particular, if the sensor output suitability determination reference value is changed according to the operating state of the engine, it becomes possible to more accurately and promptly determine sensor abnormality, and unexpected sudden changes in engine behavior. It is possible to suppress and increase the reliability of the engine.

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 shows a schematic configuration of a gas turbine engine to which the present invention is applied. This gas turbine engine 1 has a high-pressure shaft 4 that connects a compressor 2 and a high-pressure turbine 3, and a low-pressure shaft 7 that connects a low-pressure turbine 5 and a fan 6, and an outlet pressure P3 of the compressor 2 is measured by a high-pressure sensor 8. The inlet pressure P1 of the fan 6 is the low pressure sensor 9, the rotational speed N2 of the high pressure shaft 4 is the high pressure shaft rotational sensor 10, the rotational speed N1 of the low pressure shaft 7 is the low pressure shaft rotational sensor 11, and the turbine inlet temperature T3 is the high temperature sensor 12. Thus, the fuel metering valve 16 is controlled by the fuel flow controller 15 and supplied to the combustion chamber 17 so that the engine 1 shows an optimum response based on the output values of the sensors 8 to 12. The fuel flow rate is controlled. This control is performed using control parameters obtained by inputting the output values of the sensors 8 to 12 to a calibration value map 24 described later.

  Each of the sensors 8 to 12 is provided with a sensor abnormality determination device so as to be able to quickly cope with a case where the output becomes abnormal due to disconnection, for example. This abnormality determination device includes an operation mode determination unit 21, a comparison reference value setting unit 22, and a sensor abnormality determination unit 23.

  For example, the operation mode discriminating unit 21 compares the output values of the throttle lever angle sensor 14 and the high-pressure shaft rotation sensor 10 with the mode discriminating values (FIGS. 2 and 3) preset in the calibration value map 24. To determine the operation state. As the operation mode discriminated here, a start ST, a low load steady operation LR, an acceleration operation AC, a high load steady operation HR, a deceleration operation DC, an emergency fuel cut-off CO, and the like are set. In this embodiment, the mode discrimination values based on the output values of the throttle lever angle sensor 14 and the high-pressure shaft rotation sensor 10 are exemplified, but not only these values are referred to but also the values of speedometers, altimeters, etc. It may be possible to further improve the discrimination accuracy by referring to a flight schedule set in advance.

  Next, a sensor output abnormality determination processing flow according to the present invention will be described with reference to FIG.

  First, the operation mode discriminating unit 21 performs mode check, and the operation mode at that time (starting ST, low load steady operation LR, acceleration operation AC, high load steady operation HR, deceleration operation DC, emergency fuel cut-off CO). Is discriminated (step 1). Since the initial state is the start mode, the calibration value for each sensor preset in the calibration value map 24 is referred to, and the reference value for the start mode is set by the comparison reference value setting unit 22 (see FIGS. 5 and 6). Read the range A to D). (Step 2). When the start switch is turned on, the output value of each sensor is read (step 3), and this value is compared with the reference value set in the calibration value map 24 by the sensor abnormality determination unit 23. It is determined whether or not there is (step 4).

  If it is determined in step 4 that the output value of the sensor is within the specified range, it is determined that the sensor is normal, and normal start control is continued based on the output of the sensor (step 5). On the other hand, if it is determined in step 4 that the output value of the sensor is out of the specified range, it is determined that the sensor is abnormal, an alarm is issued, and a control mode (1. 2. Control is performed with an estimated value based on another sensor output 3. Control is performed by substituting the control parameter with a fixed value, and the engine is operated (step 6).

  When the start of the engine is confirmed, the result of the mode check in the operation mode discriminating unit 21 is switched to another operation mode accordingly. Therefore, the reference value of the sensor output corresponding to the operation mode (B to B in FIGS. 5 and 6). C range) is read out from each calibration value map, and the suitability of the sensor output is constantly monitored as described above.

  Here, the calibration value map 24 for reading out the discriminating value of the operation mode and the reference value for determining whether the sensor output is correct or not is used. The inlet pressure P1 of the fan 6, the outlet pressure P3 of the compressor 2, and the turbine inlet temperature T3 are in the pattern shown in FIG. The rotational speed N1 of the low pressure shaft 7 and the rotational speed N2 of the high pressure shaft 4 are set in the pattern shown in FIG. In this map, the horizontal axis is the output value of the sensor, and the vertical axis is the calibration value. That is, a calibration value corresponding to a certain sensor output value can be obtained on the vertical axis by drawing a horizontal line from the intersection of the vertical line pattern line raised from the sensor output value on the horizontal axis.

  The calibration value map 24 normally uses the calibration values obtained on the vertical axis as engine control parameters in order to compensate for the lack of linearity and resolution of the actual output of each sensor. The sensor correctness determination reference value and the operation mode determination value are set in the map so that the map can be shared. The pattern is set by adding a theoretical value to an experimental value obtained by a bench test or the like.

  Note that noise may be added to the sensor output, so judgment is not made at one sampling. For example, the output value of the sensor is sampled every 10 msec, and the previous value and the current value are compared appropriately. It is possible to make a more reliable judgment by checking whether the difference is within a predetermined value, that is, whether the output value of the sensor fluctuates and taking the result into consideration for suitability.

1 is a schematic configuration diagram of a gas turbine engine to which the present invention is applied. It is a conceptual diagram of an operation mode discriminant value map. It is a conceptual diagram of another operation mode discriminant value map. It is a control flowchart of this invention apparatus. It is a conceptual diagram of a calibration value map. It is a conceptual diagram of another calibration value map.

Explanation of symbols

21 Operation mode discriminating unit 22 Comparison reference value setting unit 23 Sensor abnormality discriminating unit

Claims (3)

A sensor output monitoring device for a gas turbine engine configured to determine whether or not the sensor output is appropriate by comparing an output of a sensor for acquiring environmental information inside and outside the engine with a predetermined reference value,
A calibration value map for obtaining parameters used for engine control in association with the output of the sensor;
A sensor output monitoring apparatus for a gas turbine engine, wherein the reference value for determining whether or not the sensor output is appropriate is set in the calibration value map.   2. The sensor output monitoring device for a gas turbine engine according to claim 1, wherein a plurality of the reference values are set in accordance with a difference in an operation state, and a value suitable for the operation state at that time is selected.   The sensor output monitoring device for a gas turbine engine according to claim 1 or 2, wherein a discrimination value of an operating state of the engine is set in the calibration value map.

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