Aero-engine low-pressure turbine rear temperature sensor signal reconstruction method, system and control system

Abstract

The application discloses an aero-engine low-pressure turbine rear temperature sensor signal reconstruction method, system and control system and belongs to the technical field of aero-engine control. The method comprises the following steps: acquiring the measurement values of multiple temperature sensors under multiple steady-state working conditions, and establishing the proportional relationship among the sensors; when a sensor fault is detected during operation, determining the number of faults; if the number of faults is less than or equal to the number of reconstructable sensors, determining the proportional coefficient according to the current rotating speed, reconstructing the fault sensor signal by using normal sensors, and fusing the reconstructed value and the measurement value of the normal sensors as the control temperature; and if the number of faults is greater than the number of reconstructable sensors, taking the average value of the measurement values of the normal sensors as the control temperature. The application overcomes the measurement deviation caused by the non-uniform turbine rear temperature field by offline calibration of the proportional relationship and online dynamic reconstruction, and can still provide high-precision temperature parameters when the sensor fails, thereby ensuring the safe operation of the engine.

Description

Technical Field

[0001] This invention belongs to the field of aero-engine control technology, specifically relating to a method, system, and control system for reconstructing signals from a low-pressure turbine back temperature sensor in an aero-engine. Background Technology

[0002] Turbine temperature signals from aircraft engines are typically used to limit engine conditions to prevent them from exceeding maximum operating limits, ensuring the engine can operate without damage and for an extended period. Currently, turbine back-end temperature sensors for aircraft engines are usually thermocouples. Due to the non-uniform temperature field behind the turbine, six sensors are generally deployed for data acquisition, and the acquired temperature signals are averaged for engine condition control.

[0003] Temperature sensors all have a certain probability of failure. When one or more temperature sensors fail, the traditional method uses the remaining working sensors for averaging calculations. However, due to the significant non-uniformity of the temperature field after the turbine, averaging calculations using only the working sensors leads to large temperature deviations. When the engine encounters a turbine-side temperature limiting control program, this deviation causes the engine's actual operating state to deviate from the limit value: if the calculated temperature is too low, the engine may operate beyond the actual limit, reducing engine lifespan over time; if the calculated temperature is too high, the engine cannot achieve maximum performance. In severe cases, temperature deviations may damage the turbine, leading to safety malfunctions.

[0004] Therefore, how to obtain accurate turbine back-end temperature parameters even when the temperature sensor fails has become a pressing technical problem in the field of aero-engine control. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by providing a method, system, and control system for reconstructing the signal of a low-pressure turbine rear temperature sensor in an aero-engine. This system can obtain accurate temperature parameters through a reconstruction algorithm when one or more temperature sensors fail, thereby reducing temperature control deviations caused by uneven temperature fields.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for reconstructing a signal from a low-pressure turbine rear temperature sensor in an aero-engine, comprising the following steps: The measurement values ​​of multiple temperature sensors after the low-pressure turbine of an aero-engine are obtained under multiple steady-state operating conditions, and the proportional relationship between the multiple temperature sensors is established. During engine operation, when a temperature sensor malfunction is detected, the number of malfunctioning sensors is determined. If the number of faulty temperature sensors is less than or equal to the number of reconfigurable sensors, then the proportional coefficients between the multiple temperature sensors are determined according to the current engine speed. Based on the real-time measurement values ​​of the temperature sensors that have not failed and the proportional coefficients, the signals of the faulty temperature sensors are reconstructed to obtain reconstructed values. The reconstructed values ​​are then fused with the measurement values ​​of the temperature sensors that have not failed to obtain the control temperature after the low-pressure turbine of the engine. If the number of faulty temperature sensors is greater than the number of reconfigurable sensors, the average value of the measurements from the non-faulty temperature sensors will be used as the control temperature after the low-pressure turbine of the engine.

[0008] Furthermore, the plurality of temperature sensors consists of six units, which are evenly arranged in the temperature field behind the low-pressure turbine.

[0009] Furthermore, the multiple steady-state operating conditions include at least an idle state, a throttling state, and a maximum state, each corresponding to a different engine speed.

[0010] Furthermore, the proportional relationship is established as follows: under each steady-state condition, the ratio between the measurements of any two temperature sensors is calculated as the proportional coefficient under that condition, and a proportional coefficient matrix is ​​formed.

[0011] Furthermore, the number of reconfigurable sensors is determined in the following way: Assuming the number of faulty temperature sensors is n, for each possible combination of n faulty temperature sensors, the signals of the n faulty temperature sensors are reconstructed using the measurement values ​​of the remaining normal temperature sensors to obtain the reconstructed values. The reconstructed value is averaged with the measured value of an actual normal temperature sensor to obtain the temperature for analog control. Calculate the error between the simulated control temperature and the average temperature measured by all actual temperature sensors; The maximum value n that makes the error less than the preset allowable error is used as the number of reconfigurable sensors.

[0012] Furthermore, determining the proportionality coefficients among the multiple temperature sensors based on the current engine speed includes: When the current engine speed is between the speeds corresponding to the two steady-state operating conditions, the proportional coefficient at the current speed is calculated using a linear interpolation method.

[0013] Furthermore, the fusion is to calculate the arithmetic mean of all normal temperature sensor measurements and all faulty temperature sensor reconstructed values.

[0014] Furthermore, when all temperature sensors fail, the control temperature at the moment before the failure is used as the current control temperature.

[0015] In a second aspect, the present invention provides a signal reconstruction system for a low-pressure turbine after-temperature sensor in an aero-engine, comprising: The proportional relationship establishment module is used to acquire the measurement values ​​of multiple temperature sensors under multiple steady-state operating conditions during the engine factory test run phase, and to establish the proportional relationship between the multiple temperature sensors. The fault detection module is used to detect whether the temperature sensor has failed in real time during engine operation and to determine the number of failed sensors. A module for determining the number of reconfigurable sensors is used to determine the number of reconfigurable temperature sensors. The number of reconfigurable sensors is determined in the following way: assuming the number of faulty temperature sensors is n, for each possible combination of n faulty temperature sensors, the signals of the n faulty temperature sensors are reconstructed using the measurement values ​​of the remaining normal temperature sensors to obtain a reconstructed value; the reconstructed value is averaged with the measurement values ​​of the actual normal temperature sensors to obtain the simulated control temperature; the error between the simulated control temperature and the average temperature of all actual temperature sensor measurements is calculated; the maximum value n that makes the error less than a preset allowable error is counted, and this value n is taken as the number of reconfigurable sensors. The reconstructing module is used to determine the proportional coefficient between the multiple temperature sensors based on the current engine speed when the number of faulty temperature sensors is less than or equal to the number of reconstructable sensors, and to reconstruct the signal of the faulty temperature sensor based on the measurement value of the non-faulty temperature sensor to obtain the reconstructed value. The temperature fusion module is used to fuse the reconstructed value with the measurement value of the non-faulty temperature sensor to obtain the control temperature when the number of faulty temperature sensors is less than or equal to the number of reconfigurable sensors; and to use the average value of the measurement value of the non-faulty temperature sensor as the control temperature when the number of faulty temperature sensors is greater than the number of reconfigurable sensors.

[0016] Thirdly, the present invention provides an aero-engine control system, including the aforementioned aero-engine low-pressure turbine after-temperature sensor signal reconstruction system.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects: 1. This invention overcomes measurement deviations caused by uneven temperature fields after the turbine by establishing a proportional relationship between temperature sensors and reconstructing the faulty sensor signal using normal temperature sensors and proportional coefficients during a fault. The reconstructed temperature value is fused with the normal temperature sensor value, accurately reflecting the true temperature after the turbine, preventing the engine from exceeding its operating limits due to temperature deviations, extending engine life, and preventing turbine damage.

[0018] 2. This invention uses the proportional coefficient calibrated during the factory test run, eliminating the need to rely on historical operating data to train the model, thus avoiding online computational overhead. This is suitable for the stringent requirements of real-time performance and reliability of embedded control systems for aero-engines.

[0019] 3. This invention determines the number of reconfigurable sensors that meet the accuracy requirements by statistically analyzing the error between the reconstructed value and the true value under different fault combinations. This ensures that within the allowable number of faults for reconfiguration, the temperature error for control after reconfiguration is less than the preset allowable value. When there are too many faults, it automatically switches to the average value of the normal temperature sensor to avoid control deviation due to excessive reconfiguration error.

[0020] 4. This invention adopts strategies such as reconstruction fusion, averaging, and preserving previous values ​​for different numbers of faults (less than or equal to the number of reconfigurable sensors, greater than the number of reconfigurable sensors, and all faults), thereby achieving temperature parameter fault tolerance under all fault scenarios and significantly improving the robustness and safety of the engine control system. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the flowchart for the method of reconstructing the low-pressure turbine back temperature sensor signal of an aero-engine according to an embodiment of the present invention; Figure 2 This is a flowchart illustrating the temperature sensor signal reconstruction method in an embodiment of the present invention. Detailed Implementation

[0023] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0024] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0025] Example 1 This embodiment provides a method for reconstructing the signal of a low-pressure turbine rear temperature sensor in an aero-engine. This method can obtain accurate temperature parameters through a reconstruction algorithm when one or more temperature sensors fail, thus ensuring engine control accuracy. Figure 1 As shown, the method includes the following steps: S1: Establish the proportional relationship between multiple temperature sensors In this embodiment, six temperature sensors are uniformly arranged in the temperature field behind the low-pressure turbine of the aero-engine, denoted as T. t5-1A T t5-1B T t5-2A T t5-2B T t5-3A T t5-3B .

[0026] Specifically, such as Figure 2 As shown, during the engine factory test run, the measured values ​​of each temperature sensor under multiple steady-state conditions are obtained. The multiple steady-state conditions include at least the idle state, the throttling state, and the maximum state, which correspond to different engine speeds (idle state Nf=30%, throttling state Nf=60%, maximum state Nf=90%).

[0027] Under each steady-state condition, the ratio between the measurements of any two temperature sensors is calculated as the proportionality coefficient for that condition, and a proportionality coefficient matrix is ​​formed to establish the proportional relationship between the multiple temperature sensors under the multiple steady-state conditions. Table 1 shows the proportionality coefficient matrix between each temperature sensor.

[0028] Table 1. Proportional Relationship Among Temperature Sensors

[0029] In Table 1, K1a1b represents the steady-state time T t5-1A T t5-1BThe proportionality coefficient between temperature sensors, i.e., K1a1b=T t5-1A / T t5-1B And so on for the rest.

[0030] Using the above method, proportional coefficient matrices can be established for slow, throttling, and maximum states, as shown in Tables 2, 3, and 4, respectively.

[0031] Table 2 Matrix of proportional coefficients between temperature sensors under slow operation

[0032] Table 3 Matrix of proportional coefficients between temperature sensors under throttling conditions

[0033] Table 4 Matrix of proportional coefficients between temperature sensors under maximum conditions

[0034] After establishing the proportional relationship between temperature sensors under the above stable operating conditions, the proportional relationship is written into the adjustable parameters of the engine control system.

[0035] This step, through factory test calibration, pre-obtains a fixed proportional relationship between temperature sensors under different operating conditions, providing a benchmark for subsequent fault reconstruction. It avoids the computational overhead required for online model training and is suitable for the real-time requirements of embedded control systems for aero-engines.

[0036] S2: Determine the number of reconfigurable sensors Before the engine is put into use, the number of reconfigurable sensors needs to be determined in advance. This parameter indicates that when the number of faulty sensors does not exceed this value, the control temperature obtained by the reconfiguration method described in this embodiment of the invention can meet the accuracy requirements; when the number of faulty sensors exceeds this value, the reconfiguration error may exceed the allowable range, and in this case, the average value of the normal sensors should be used directly.

[0037] In this embodiment, the example is taken as having 3 reconfigurable sensors. The process for determining this value is as follows: Assuming the number of faulty sensors is n, for each possible combination of n faulty temperature sensors, the signals of the n faulty temperature sensors are reconstructed using the measurements from the remaining normal temperature sensors to obtain reconstructed values. Specifically, for a given fault combination, a corresponding proportionality coefficient is determined based on the engine speed at the time of the fault (using the method in step S3), and the reconstructed values ​​of each faulty temperature sensor are calculated using the measurements from the remaining normal temperature sensors and the proportionality coefficient.

[0038] The reconstructed value is averaged with the measured value from a normal temperature sensor to obtain the simulated control temperature. This simulated control temperature represents the final temperature value used for engine control if the reconstruction is performed using the method described in this embodiment of the invention.

[0039] Calculate the error between the simulated control temperature and the actual average temperature measured by all temperature sensors. The actual average temperature measured by all sensors is the arithmetic mean of the measurements from the six temperature sensors, assuming all sensors are functioning normally.

[0040] The maximum value n that makes the error less than the preset allowable error is used as the number of reconfigurable sensors.

[0041] In this embodiment, the preset allowable error is ±20℃. This allowable error can be determined based on factors such as engine model and control accuracy requirements. The ±20℃ setting in this embodiment is merely an example. By traversing all possible fault combinations, statistical results show that when n=3, the temperature error for simulation control under all fault combinations is less than 20℃. Therefore, the number of reconfigurable sensors is determined to be 3. This means that when 1, 2, or 3 temperature sensors fail, the reconfiguration method described in this invention can be used; when 4 or more sensors fail, the reconfiguration error may exceed the allowable range, and the average value of the normal sensors should be directly taken.

[0042] This step uses offline statistics to scientifically determine the number of reconfigurable sensors based on the accuracy requirements of the final control temperature, providing accurate decision-making basis for online fault handling and ensuring that the engine can obtain temperature parameters that meet the accuracy requirements under any fault condition.

[0043] S3: Fault Detection and Handling During Online Operation like Figure 2 As shown, the operating status of six temperature sensors is monitored in real time during actual engine operation. If all temperature sensors are functioning correctly, the average value of the measurements from the six sensors is taken as the control temperature T after the low-pressure turbine of the engine. t5 The control temperature T after the low-pressure turbine of the engine is calculated using the following formula. t5 : T t5 = (T t5-1A + T t5-1B + T t5-2A + T t5-2B + T t5-3A + T t5-3B ) / 6 When at least one temperature sensor is detected to be faulty, determine the number of faulty sensors.

[0044] Scenario 1: The number of faulty sensors is less than or equal to the number of reconfigurable sensors (3 in this example). At this point, the proportional coefficients between multiple temperature sensors are determined based on the current engine speed (which can be obtained from the engine control system). Specifically, when the current engine speed is between the speeds corresponding to two steady-state operating conditions, a linear interpolation method is used to calculate the proportional coefficients at the current speed.

[0045] (1) Example of a single sensor failure Assume that there is only T at present t5-1A If a fault occurs, the current engine speed Nf = 50% (between 30% and 60%). The proportional coefficients between each temperature sensor are obtained from the idle state proportional coefficient matrix (Table 2) and the throttle state proportional coefficient matrix (Table 3). Then, linear interpolation is performed according to the engine speed to obtain the proportional coefficients between each temperature sensor at Nf = 50%, forming a proportional coefficient matrix as shown in Table 5.

[0046] Table 5 Matrix of proportional coefficients between temperature sensors at current rotational speed

[0047] According to Table 5, obtain the information related to T. t5-1A The relevant proportionality coefficients (K1a1b, K1a2a, K1a2b, K1a3a, K1a3b) are used to calculate the faulty temperature sensor T based on the real-time measurements of the five temperature sensors that are not faulty. t5-1A The signal is reconstructed to obtain the reconstructed value. The reconstruction formula is as follows: T t5-1A-rec = (T t5-1B ×K1a1b +T t5-2A ×K1a2a + T t5-2B ×K1a2b + T t5-3A ×K1a3a +T t5-3B ×K1a3b) / 5 This formula uses the measurements from the other five temperature sensors, and converts them to T values ​​through a proportional relationship. t5-1A The position is determined, and then the average value is taken as T. t5-1A The reason for this processing is that the temperature field after the turbine is not uniform, and the temperature at different locations has a fixed proportional relationship. By combining and calculating from multiple sensors, the random error of single-point measurement can be offset, and a more accurate temperature value can be obtained.

[0048] After obtaining the reconstructed value, it is fused with the measurements from the five temperature sensors that did not malfunction to obtain the control temperature T after the low-pressure turbine of the engine. t5In this embodiment, the fusion method is to calculate the arithmetic mean of the measured values ​​of all normal temperature sensors and the reconstructed values ​​of all faulty temperature sensors, that is: T t5 = (T t5-1A-rec + T t5-1B + T t5-2A + T t5-2B + T t5-3A + T t5-3B ) / 6 Using the above method, when any one temperature sensor fails, its temperature value can be reconstructed, and the control temperature after the low-pressure turbine of the engine can be calculated based on the reconstructed value. The reconstruction method for the other temperature sensors is the same as described above, and will not be repeated here.

[0049] (2) Example of failure of two sensors Suppose that two temperature sensors are currently malfunctioning (e.g., T). t5-1A T t5-1B (Faulty), the other four temperature sensors are working normally. The proportional coefficient between each temperature sensor is determined based on the current engine speed, and then the normal temperature sensor T is used. t5-2A T t5-2B T t5-3A T t5-3B For T respectively t5-1A T t5-1B The signal is reconstructed to obtain the reconstructed value. The reconstruction formula is as follows: T t5-1A-rec = (T t5-2A ×K1a2a + T t5-2B ×K1a2b + T t5-3A ×K1a3a + T t5-3B ×K1a3b) / 4; T t5-1B-rec = (T t5-2A ×K1b2a + T t5-2B ×K1b2b + T t5-3A ×K1b3a + T t5-3B ×K1b3b) / 4; After obtaining the reconstructed values ​​from the two faulty temperature sensors, they are averaged and fused with the measured values ​​from the four normal temperature sensors to obtain the control temperature T after the low-pressure turbine of the engine. t5 : T t5 = (T t5-1A-rec + T t5-1B-rec + T t5-2A + T t5-2B + T t5-3A + T t5-3B) / 6 The reconstruction method for any two temperature sensors malfunctioning is the same as described above, and will not be repeated here.

[0050] (3) Example of three sensor failures Suppose that three temperature sensors fail simultaneously (e.g., T). t5-1A T t5-1B T t5-2A (The fault was detected), while the other three temperature sensors were functioning normally. The proportional coefficient between each temperature sensor was determined based on the current engine speed, and then T... t5-2B T t5-3A T t5-3B For T respectively t5-1A T t5-1B T t5-2A The signal is reconstructed to obtain the reconstructed value. The reconstruction formula is as follows: T t5-1A-rec = ( T t5-2B ×K1a2b + T t5-3A ×K1a3a + T t5-3B ×K1a3b) / 3; T t5-1B-rec = (T t5-2B ×K1b2b + T t5-3A ×K1b3a + T t5-3B ×K1b3b) / 3; T t5-2A-rec = (T t5-2B ×K2a2b + T t5-3A ×K2a3a + T t5-3B ×K2a3b) / 3; After obtaining the reconstructed values ​​from the three faulty temperature sensors, they are averaged and fused with the measured values ​​from the three normal temperature sensors to obtain the control temperature T after the low-pressure turbine of the engine. t5 : T t5 = (T t5-1A-rec + T t5-1B-rec + T t5-2A-rec + T t5-2B + T t5-3A + T t5-3B ) / 6 The reconstruction method for any three temperature sensors malfunctioning is the same as described above, and will not be repeated here.

[0051] When the number of faulty sensors does not exceed the number of reconfigurable sensors (3), the temperature value of the faulty sensor is dynamically reconstructed using the pre-calibrated proportional relationship and current operating data, and participates in the average value calculation, so as to retain the information of the 6 sensors to the maximum extent and overcome the deviation caused by the uneven temperature field.

[0052] Scenario 2: The number of faulty sensors is greater than the number of reconfigurable sensors (3), and not all temperature sensors are faulty. At this point, without signal reconstruction, the average value of the measurements from the temperature sensors that have not malfunctioned is directly used as the control temperature T after the low-pressure turbine of the engine. t5 .

[0053] For example, suppose there are 4 temperature sensors (T t5-1A T t5-1B T t5-2A T t5-2B The first temperature sensor malfunctioned, leaving two temperature sensors (T) remaining. t5-3A T t5-3B It is working normally. At this time, T t5 = (T t5-3A +T t5-3B ) / 2.

[0054] For example, suppose 5 temperature sensors fail, and the remaining 1 stable sensor works normally, then T t5 It equals the measured value of that sensor.

[0055] When the number of faulty sensors is too large (≥4), the reconstruction error may exceed the allowable range. In this case, abandoning reconstruction and directly using the average value of the normal sensors, although some information is lost, can ensure that the error of the temperature control is within an acceptable range. This is a safe fault-tolerant strategy.

[0056] Scenario 3: All temperature sensors malfunction (all 6 sensors fail) At this point, the control temperature at the moment before the fault is detected is used as the current control temperature until the sensor recovers or the engine stops.

[0057] This strategy can keep the engine running safely for a short period of time in the extreme case of a complete failure, giving the pilot or control system time to react.

[0058] Example 2 This embodiment provides a signal reconstruction system for a low-pressure turbine back temperature sensor in an aero-engine, which is used to implement the method described in Embodiment 1.

[0059] The system includes: The proportional relationship establishment module is used during the engine factory testing phase to acquire the measured values ​​of multiple temperature sensors under various steady-state operating conditions and establish the proportional relationship between the multiple temperature sensors. Specifically, this module calculates the ratio between the measured values ​​of any two temperature sensors under idle, throttling, and maximum operating conditions, forming a proportional coefficient matrix for each operating condition, and writes these matrices into the adjustable parameters of the engine control system.

[0060] This module establishes quantitative relationships between temperature sensors in advance through offline calibration, providing benchmark data for subsequent online reconstruction and avoiding the real-time pressure brought by online calculation.

[0061] The fault detection module is used to detect whether temperature sensors have malfunctioned in real time during engine operation and to determine the number of malfunctioning temperature sensors. Fault detection can employ conventional sensor self-test methods, such as open circuit detection, range checks, and rate of change checks.

[0062] This module monitors the temperature sensor status in real time, identifies faults promptly, and counts the number of faults, providing input for subsequent decision-making.

[0063] A module for determining the number of reconfigurable sensors is used to determine the number of reconfigurable temperature sensors. This module determines the number as follows: assuming the number of faulty sensors is n, for each possible combination of n faulty temperature sensors, the signals of the n faulty temperature sensors are reconstructed using the measurement values ​​of the remaining normal and stable sensors to obtain reconstructed values; the reconstructed values ​​are averaged with the measurement values ​​of the actual normal temperature sensors to obtain the simulated control temperature; the error between the simulated control temperature and the average temperature of all actual temperature sensor measurements is calculated; and the maximum value n that makes the error less than a preset allowable error is calculated, and this value n is taken as the number of reconfigurable sensors.

[0064] Based on the accuracy requirements of the final control temperature, this module scientifically determines the number of reconfigurable sensors, providing accurate decision thresholds for online fault handling.

[0065] The reconstruction module is used to determine the proportional coefficients between multiple temperature sensors based on the current engine speed when the number of faulty temperature sensors is less than or equal to the number of reconstructable sensors (e.g., 3). It then reconstructs the signal of the faulty temperature sensor based on the measured values ​​of the non-faulty temperature sensors to obtain a reconstructed value. Specifically, when the current engine speed is between the speeds corresponding to two steady-state operating conditions, a linear interpolation method is used to calculate the proportional coefficients at the current speed. Then, using the measured values ​​of the non-faulty temperature sensors and the interpolated proportional coefficients, the reconstructed value of the faulty temperature sensor is calculated according to the reconstruction formula in Example 1.

[0066] Within the allowed number of reconfigurable faults, this module dynamically calculates the reconfiguration value of the faulty sensor to recover the missing measurement information to the greatest extent possible.

[0067] The temperature fusion module is used to fuse the reconstructed value with the measurement value of the non-faulty temperature sensor to obtain the control temperature when the number of faulty temperature sensors is less than or equal to the number of reconfigurable sensors; when the number of faulty temperature sensors is greater than the number of reconfigurable sensors, the average value of the measurement values ​​of the non-faulty temperature sensors is used as the control temperature; and when all temperature sensors are faulty, the temperature value at the moment before the fault is output as the control temperature.

[0068] Based on the number of faults and the feasibility of reconfiguration, this module selects the optimal temperature fusion strategy to ensure that the control temperature after the low-pressure turbine of the engine can meet the accuracy requirements under any circumstances.

[0069] Example 3 This embodiment provides an aero-engine control system, including the aero-engine low-pressure turbine after-temperature sensor signal reconstruction system described in Embodiment 2. This control system can be a full-authority digital electronic control system (FADEC), integrating the reconstruction system as a functional module.

[0070] During engine operation, when a temperature sensor malfunctions, the control system invokes the temperature sensor signal reconstruction system to reconstruct the faulty temperature sensor signal according to the method described in Example 1, or employs a backup strategy, ultimately outputting an accurate T value. t5 Temperature values ​​are used for engine condition limits and control.

[0071] This control system integrates the fault tolerance capability of the temperature sensor directly into the core engine control system, without requiring additional hardware, increasing system weight and complexity, while improving the engine's safety and availability in fault conditions.

[0072] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, various modifications and variations can be made to the embodiments of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for reconstructing a low-pressure turbine after-temperature sensor signal in an aero-engine, characterized in that, Includes the following steps: The measurement values ​​of multiple temperature sensors after the low-pressure turbine of an aero-engine are obtained under multiple steady-state conditions, and the proportional relationship between the multiple temperature sensors under the multiple steady-state conditions is established respectively. During engine operation, when a temperature sensor malfunction is detected, the number of malfunctioning temperature sensors is determined. If the number of faulty temperature sensors is less than or equal to the number of reconfigurable sensors, then the proportional coefficients between the multiple temperature sensors are determined based on the current engine speed. Based on the real-time measurement values ​​of the temperature sensors that are not malfunctioning and the proportional coefficient, the signals of the malfunctioning temperature sensors are reconstructed to obtain reconstructed values. These reconstructed values ​​are then fused with the measurement values ​​of the temperature sensors that are not malfunctioning to obtain the control temperature after the low-pressure turbine of the engine. The number of reconstructable sensors is determined in the following way: Assuming the number of faulty temperature sensors is n, for each possible combination of n faulty temperature sensors, the signals of the n faulty temperature sensors are reconstructed using the measurement values ​​of the remaining normal temperature sensors to obtain the reconstructed values. The reconstructed value is averaged with the measured value of an actual normal temperature sensor to obtain the temperature for analog control. Calculate the error between the simulated control temperature and the average temperature measured by all actual temperature sensors; The maximum value n that makes the error less than the preset allowable error is used as the number of reconfigurable sensors. The step of determining the proportional coefficients between the multiple temperature sensors based on the current engine speed includes: when the current engine speed is between the speeds corresponding to two steady-state operating conditions, using a linear interpolation method to calculate the proportional coefficients at the current speed; If the number of faulty temperature sensors is greater than the number of reconfigurable sensors, the average value of the measurements from the non-faulty temperature sensors will be used as the control temperature after the low-pressure turbine of the engine.

2. The method for reconstructing the low-pressure turbine after-temperature sensor signal of an aero-engine according to claim 1, characterized in that, The multiple temperature sensors consist of six units, which are evenly arranged in the temperature field after the low-pressure turbine.

3. The method for reconstructing the low-pressure turbine after-temperature sensor signal of an aero-engine according to claim 1, characterized in that, The multiple steady-state operating conditions include at least the idle state, the throttling state, and the maximum state, each corresponding to a different engine speed.

4. The method for reconstructing the low-pressure turbine after-temperature sensor signal of an aero-engine according to claim 3, characterized in that, The proportional relationship is established as follows: under each steady-state condition, the ratio between the measurements of any two temperature sensors is calculated as the proportional coefficient under that condition, and a proportional coefficient matrix is ​​formed.

5. The method for reconstructing the low-pressure turbine after-temperature sensor signal of an aero-engine according to claim 1, characterized in that, The fusion is calculated as the arithmetic mean of all normal temperature sensor measurements and all faulty temperature sensor reconstructed values.

6. The method for reconstructing the low-pressure turbine after-temperature sensor signal of an aero-engine according to claim 1, characterized in that, When all temperature sensors fail, the control temperature at the moment before the failure is used as the current control temperature.

7. A signal reconstruction system for a low-pressure turbine after-temperature sensor in an aero-engine, characterized in that, include: The proportional relationship establishment module is used to acquire the measurement values ​​of multiple temperature sensors under multiple steady-state operating conditions during the engine factory test run phase, and to establish the proportional relationship between the multiple temperature sensors. The fault detection module is used to detect whether the temperature sensor has failed in real time during engine operation and to determine the number of temperature sensors that have failed. A module for determining the number of reconfigurable sensors is used to determine the number of reconfigurable temperature sensors. The number of reconfigurable sensors is determined in the following way: assuming that the number of faulty temperature sensors is n, for each possible combination of n faulty temperature sensors, the signals of the n faulty temperature sensors are reconstructed using the measurement values ​​of the remaining normal temperature sensors to obtain a reconstructed value; the reconstructed value is averaged with the measurement values ​​of the actual normal temperature sensors to obtain the temperature for analog control. Calculate the error between the simulated control temperature and the average temperature measured by all actual temperature sensors; count the maximum n value that makes the error less than the preset allowable error, and use this n value as the number of reconfigurable sensors; The reconstructing module is used to determine the proportional coefficient between the multiple temperature sensors based on the current engine speed when the number of faulty temperature sensors is less than or equal to the number of reconstructable sensors, and to reconstruct the signal of the faulty temperature sensor based on the measurement value of the non-faulty temperature sensor to obtain the reconstructed value. The step of determining the proportional coefficients between the multiple temperature sensors based on the current engine speed includes: when the current engine speed is between the speeds corresponding to two steady-state operating conditions, using a linear interpolation method to calculate the proportional coefficients at the current speed; The temperature fusion module is used to fuse the reconstructed value with the measurement value of the non-faulty temperature sensor to obtain the control temperature when the number of faulty temperature sensors is less than or equal to the number of reconfigurable sensors; and to use the average value of the measurement value of the non-faulty temperature sensor as the control temperature when the number of faulty temperature sensors is greater than the number of reconfigurable sensors.

8. An aircraft engine control system, characterized in that, Includes the aircraft engine low-pressure turbine after-temperature sensor signal reconstruction system as described in claim 7.

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