Sensor fault dynamic diagnosis method, system, medium and equipment

Abstract

The invention discloses a sensor fault dynamic diagnosis method and system for fault tolerance of an engine control system, a medium and equipment, and the method comprises the steps: calculating a predicted value of a gas path parameter through an engine part-level model according to an input parameter; calculating a residual signal between the measured value of each gas path parameter sensor and the corresponding gas path parameter predicted value; filtering the gas path parameter residual signal; calculating a root-mean-square error between the predicted value of the low-pressure rotor speed of the engine and the measured value of the low-pressure rotating speed sensor, and recording the root-mean-square error as a predicted error of the low-pressure rotor speed; calculating corresponding dynamic thresholds for fault diagnosis of other gas path sensors by taking the prediction error of the rotating speed of the low-pressure rotor as a reference; setting a fault indicator, if a residual error between a sensor measurement value and a model prediction value is greater than a dynamic threshold value, increasing an indicator value, otherwise, decreasing the indicator value; when the fault indicator value is greater than a set counting boundary, a sensor fault is reported.

Description

Technical Field

[0001] The present invention relates to the technical field of engine sensor fault diagnosis, and in particular to a sensor fault dynamic diagnosis method, system, medium and equipment for engine control system fault tolerance. Background Art

[0002] Sensors are important information sources for engine control systems, and the reliability of their measurement signals directly affects the safe operation of the engine. As important components working in harsh working environments such as high temperature, high pressure, and strong vibration, sensors are prone to failure, which in turn affects the calculation results of the engine controller. Sensor fault detection, isolation, and disposal are important aspects of the fault-tolerant design of engine control systems.

[0003] Sensor fault diagnosis based on the residual signal between the sensor measurement value and the engine model prediction value is an important diagnostic method. The residual size is compared with the fault threshold to determine the fault condition of the sensor. Due to the complexity of the engine service conditions and the variability of the working state, the size of the prediction residual will change with the thermal state of the engine. In addition, a larger fixed fault threshold may lead to a large number of faults being missed, while a smaller fixed fault threshold may cause false alarms, affecting the effectiveness of the subsequent control actions of the control system. Therefore, it is necessary to design a dynamic fault threshold related to the thermal state of the engine to accurately and reliably diagnose sensor faults.

[0004] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the invention

[0005] The present invention provides a sensor fault dynamic diagnosis method, system, medium and equipment for engine control system fault tolerance, which takes the prediction error of parameters related to the engine thermal state as a benchmark, such as low-pressure speed, and calculates the dynamic thresholds corresponding to other sensors except low-pressure speed for sensor fault diagnosis.

[0006] The dynamic diagnosis method of sensor faults for engine control system fault tolerance includes:

[0007] Step 100, detecting and recording sensor measurement values ​​of the engine, and calculating gas path parameter prediction values ​​of the engine component level model based on the engine component level model corresponding to the engine;

[0008] Step 200, calculating a residual signal between a measured value of each gas path parameter sensor and a corresponding predicted value of the gas path parameter, and filtering the residual signal;

[0009] Step 300, calculating the root mean square error of the low-pressure rotor speed prediction value, recorded as the low-pressure rotor speed prediction error, and using the prediction error as a reference, calculating the dynamic threshold corresponding to the fault diagnosis of other gas path sensors;

[0010] Step 400, setting a sensor fault detection counter, and calculating the value of the fault detection counter based on the comparison between the filtered residual signal and the dynamic threshold;

[0011] Step 500, compare the counter value with the counter setting value, if the counter value exceeds the setting value, report a fault.

[0012] In the sensor fault dynamic diagnosis method for engine control system fault tolerance, the engine includes a low-pressure rotor, a high-pressure rotor, a low-pressure compressor, a high-pressure compressor, a high-pressure turbine and a low-pressure turbine.

[0013] In the sensor fault dynamic diagnosis method for engine control system fault tolerance, the sensor measurement value includes engine input parameters and gas path parameters. The input parameter I at time t E (t)={T t0 (t), P t0 (t), W f (t),A8(t)}, where T t0 (t) is the total intake air temperature, P t0 (t) is the total intake pressure, W f (t) is the fuel flow rate, A8(t) is the nozzle area, and the gas path parameter O at time t E (t)={N L,E (t), N H,E (t), P t25,E (t), P t31,E (t), T t6,E (t)}, where N L,E (t) is the measured value of the low-pressure rotor speed, N H,E (t) is the measured value of the high pressure rotor speed, P t25,E (t) is the measured value of the pressure at the outlet of the low-pressure compressor, P t31,E (t) is the measured value of the pressure at the outlet of the high pressure compressor, T t6,E (t) is the measured value of the temperature at the low-pressure turbine outlet.

[0014] In the sensor fault dynamic diagnosis method for engine control system fault tolerance, according to the engine input parameter I E (t) Calculate the predicted value of the gas path parameter at time t O M (t)={N L,M (t), N H,M (t), Pt25,M (t), P t31,M (t), T t6,M (t)}, where N L,M (t) is the predicted value of low-pressure rotor speed calculated by the engine component level model, N H,M (t) is the predicted value of the high-pressure rotor speed calculated by the engine component level model, P t25,M (t) is the predicted value of the pressure at the outlet of the low-pressure compressor calculated by the engine component level model, P t31,M (t) is the predicted value of the pressure at the high pressure compressor outlet calculated by the engine component level model, T t6,M (t) is the predicted value of the temperature at the low-pressure turbine outlet calculated by the engine component level model.

[0015] In the sensor fault dynamic diagnosis method for engine control system fault tolerance, in step 200, the prediction residual is calculated by: H , P t25 , P t31 and T t6 The numbers are recorded from 1 to 4 in sequence, and the measurement value of the i-th sensor at time t is recorded as O E,i (t), the predicted value of the i-th sensor at time t is recorded as O M,i (t), calculate the prediction residual of the i-th sensor at time t .

[0016] In the sensor fault dynamic diagnosis method for engine control system fault tolerance, in step 200, the filtering calculation formula of the residual signal is:

[0017]

[0018] in, is the smoothed residual at time t, and θ is a smoothing factor between 0 and 1.

[0019] In the sensor fault dynamic diagnosis method for engine control system fault tolerance, in step 300, the low-pressure rotor speed prediction value N at time t is calculated. L,M The root mean square error R(t) corresponding to (t) is used as the dynamic threshold for fault diagnosis of the high-pressure rotor speed sensor, the low-pressure compressor outlet pressure sensor, the high-pressure compressor outlet pressure sensor and the low-pressure turbine outlet temperature sensor. The iterative calculation formula of the root mean square error R(t) is:

[0020] , where L R is the calculation window length, R(t-1) is the root mean square error at time t-1, and N L,M (tL R) is tL R The predicted value of low-pressure rotor speed at time N L,E (tL R ) is tL R The measured value of the low-pressure rotor speed sensor at time.

[0021] A sensor fault dynamic diagnosis system for engine control system fault tolerance includes:

[0022] A measuring unit detects and records the measured values ​​of the gas path parameter sensor of the engine, and calculates the predicted values ​​of the gas path parameters of the engine component level model based on the engine component level model corresponding to the engine;

[0023] A residual unit, which is used to: calculate the residual signal between the measured value of each gas path parameter sensor and the corresponding gas path parameter predicted value, and filter the residual signal;

[0024] A threshold calculation unit, which is used to: calculate the root mean square error of the low-pressure rotor speed prediction value, recorded as the low-pressure rotor speed prediction error, and use the prediction error as a reference to calculate the dynamic threshold corresponding to the fault diagnosis of other gas path sensors;

[0025] A fault detection counter is used to calculate the value of the fault detection counter based on the comparison between the residual signal after filtering and the dynamic threshold;

[0026] The comparison unit is used to compare the counter value with the counter setting value, and report a fault if the counter value exceeds the setting value.

[0027] A computer storage medium includes computer instructions, which, when executed on a computer, cause the computer to execute the method described above.

[0028] An electronic device, comprising:

[0029] A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein:

[0030] When the processor executes the program, the method described is implemented.

[0031] Compared with the prior art, the beneficial effects of the present disclosure are as follows: the low-pressure rotor speed of the present method is an important parameter representing the thermal state of the engine, the measurement reliability and accuracy of the speed signal are higher, and the low-pressure rotor speed prediction error is used as the design basis for the dynamic threshold of other sensor fault diagnosis. Combining sensor signal filtering, dynamic threshold and fault counter, the high fault missed detection rate and high false alarm rate problems existing in the sensor fault diagnosis method based on fixed threshold are solved, and the bias and drift faults of the sensor can be diagnosed in time, which has the characteristics of simple algorithm and easy implementation. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] By reading the detailed description of the preferred specific embodiments below, various other advantages and benefits of the present invention will become clear to those of ordinary skill in the art. The drawings in the specification are only for the purpose of illustrating the preferred embodiments and are not considered to be limitations of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative work. Moreover, the same reference numerals are used to represent the same components throughout the drawings.

[0033] In the attached picture:

[0034] Figure 1 It is an architecture diagram of a sensor fault dynamic diagnosis method for engine control system fault tolerance provided by an embodiment of the present disclosure;

[0035] FIG. 2( a ) is a diagram of a sensor P provided by an embodiment of the present disclosure. t25 Schematic diagram of bias failure, FIG2(b) is a sensor P provided by an embodiment of the present disclosure t25 Drift fault diagram;

[0036] FIG. 3( a ) is a diagram of a sensor P provided by an embodiment of the present disclosure. t25 Schematic diagram of bias fault diagnosis results, FIG3(b) is a diagram of a sensor P provided by an embodiment of the present disclosure t25 Schematic diagram of drift fault diagnosis results.

[0037] The present invention is further explained below in conjunction with the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0038] The specific embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the specific embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0039] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present invention, but the description is based on the general principles of the specification and is not intended to limit the scope of the present invention. The scope of protection of the present invention shall be determined by the attached claims.

[0040] To facilitate understanding of the embodiments of the present invention, further explanation will be given below by taking specific embodiments as examples in conjunction with the accompanying drawings, and each of the accompanying drawings does not constitute a limitation on the embodiments of the present invention.

[0041] like Figure 1 to Figure 3(b) As shown, the dynamic diagnosis method of sensor faults for engine control system fault tolerance includes:

[0042] Step 100, detecting and recording sensor measurement values ​​of the engine, and calculating gas path parameter prediction values ​​of the engine component level model based on the engine component level model corresponding to the engine;

[0043] Step 200, calculating a residual signal between a measured value of each gas path parameter sensor and a corresponding predicted value of the gas path parameter, and filtering the residual signal;

[0044] Step 300, calculating the root mean square error of the low-pressure rotor speed prediction value, recorded as the low-pressure rotor speed prediction error, and using the prediction error as a reference, calculating the dynamic threshold corresponding to the fault diagnosis of other gas path sensors;

[0045] Step 400, setting a sensor fault detection counter, and calculating the value of the fault detection counter according to the comparison between the filtered residual signal and the dynamic threshold;

[0046] Step 500, compare the counter value with the counter setting value, if the counter value exceeds the setting value, report a fault.

[0047] In a preferred embodiment of the sensor fault dynamic diagnosis method for engine control system fault tolerance, the engine includes a low-pressure rotor, a high-pressure rotor, a low-pressure compressor, a high-pressure compressor, a high-pressure turbine and a low-pressure turbine.

[0048] In a preferred embodiment of the sensor fault dynamic diagnosis method for engine control system fault tolerance, the sensor measurement value includes engine input parameters and gas path parameters, and the input parameter I at time tE (t)={T t0 (t),P t0 (t), W f (t), A8(t)}, where T t0 (t) is the total intake air temperature, P t0 (t) is the total intake pressure, W f (t) is the fuel flow rate, A8(t) is the nozzle area, and the gas path parameter O at time t E (t)={N L,E (t), N H,E (t), P t25,E (t), P t31,E (t), T t6,E (t)}, where N L,E (t) is the measured value of the low-pressure rotor speed, N H,E (t) is the measured value of the high pressure rotor speed, P t25,E (t) is the measured value of the pressure at the outlet of the low-pressure compressor, P t31,E (t) is the measured value of the pressure at the outlet of the high pressure compressor, T t6,E (t) is the measured value of the temperature at the low-pressure turbine outlet.

[0049] In a preferred embodiment of the sensor fault dynamic diagnosis method for engine control system fault tolerance, according to the engine input parameter I E (t) Calculate the predicted value of the gas path parameter at time t O M (t)={N L,M (t), N H,M (t),P t25,M (t), P t31,M (t), T t6,M (t)}, where N L,M (t) is the predicted value of low-pressure rotor speed calculated by the engine component level model, N H,M (t) is the predicted value of the high-pressure rotor speed calculated by the engine component level model, P t25,M (t) is the predicted value of the pressure at the outlet of the low-pressure compressor calculated by the engine component level model, P t31,M (t) is the predicted value of the pressure at the high pressure compressor outlet calculated by the engine component level model, T t6,M (t) is the predicted value of the temperature at the low-pressure turbine outlet calculated by the engine component level model.

[0050] In the preferred implementation of the sensor fault dynamic diagnosis method for engine control system fault tolerance, in step 200, the prediction residual is calculated by: H , P t25 , P t31 and Tt6 The numbers are recorded from 1 to 4 in sequence, and the measurement value of the i-th sensor at time t is recorded as O E,i (t), the predicted value of the i-th sensor at time t is recorded as O M,i (t), calculate the prediction residual of the i-th sensor at time t .

[0051] In a preferred implementation of the sensor fault dynamic diagnosis method for engine control system fault tolerance, the filtering calculation formula of the residual signal is:

[0052]

[0053] in, is the smoothed residual at time t, and θ is a smoothing factor between 0 and 1.

[0054] In the preferred embodiment of the sensor fault dynamic diagnosis method for engine control system fault tolerance, in step 300, the low-pressure rotor speed prediction value N at time t is calculated. L,M The root mean square error R(t) of (t) is used to calculate the predicted value of low-pressure rotor speed N L,M The dynamic threshold value of the fault diagnosis of the high-pressure rotor speed sensor, the low-pressure compressor outlet pressure sensor, the high-pressure compressor outlet pressure sensor and the low-pressure turbine outlet temperature sensor other than (t) is calculated by the iterative calculation formula of the root mean square error R(t):

[0055] , where L R is the calculation window length, R(t-1) is the root mean square error at time t-1, and N L,M (tL R ) is tL R The predicted value of low-pressure rotor speed at time N L,E (tL R ) is tL R The measured value of the low-pressure rotor speed sensor at time.

[0056] In the preferred embodiment of the sensor fault dynamic diagnosis method for engine control system fault tolerance, the root mean square error of the low-pressure rotor speed is used to calculate the i-th sensor fault diagnosis dynamic threshold as a function of the root mean square error R(t), expressed as

[0057] ,

[0058] Among them, δ i (t) is the dynamic threshold for fault diagnosis of the i-th sensor, ε i,k is the proportionality coefficient, ε i,b is the bias coefficient.

[0059] In a preferred embodiment of the sensor fault dynamic diagnosis method for engine control system fault tolerance, in step 400, the fault detection counter counts the fault detection of the i-th sensor as follows:

[0060]

[0061] Among them, the value of the counter is a non-negative number, that is, m i (t)≥0.

[0062] In a preferred embodiment of the sensor fault dynamic diagnosis method for engine control system fault tolerance, in step 400, the method for calculating the value of the fault detection counter is as follows: when the residual The absolute value of is less than the dynamic threshold δ i (t), counter m i (t) decreases, if m i (t)<0, then m i (t) is set to 0, when the residual The absolute value of exceeds the dynamic threshold δ i (t), counter m i (t)Increase.

[0063] In one embodiment, in step 500, the fault detection counter reports a fault in the following manner: Exceeding the dynamic threshold δ for a period of time i (t), that is, satisfying m i (t)>m f,i When , the i-th sensor is reported to be faulty. Among them, the counting boundary m f,i It is a constant and the value can be set according to specific needs.

[0064] In one embodiment, Figure 1 As shown, the method includes,

[0065] Step 100, recording the measured values ​​of the gas path parameter sensors of the engine and the predicted values ​​of the gas path parameters of the engine component level model;

[0066] Step 200, calculating the prediction residuals of the high-pressure rotor speed, the low-pressure compressor outlet pressure, the high-pressure compressor outlet pressure and the low-pressure turbine outlet temperature, and filtering the residual signal;

[0067] Step 300, calculating the root mean square error corresponding to the low-pressure rotor speed prediction value, which is used for the fault diagnosis dynamic threshold of the high-pressure rotor speed sensor, the low-pressure compressor outlet pressure sensor, the high-pressure compressor outlet pressure sensor and the low-pressure turbine outlet temperature sensor;

[0068] Step 400, setting a sensor fault detection counter, and calculating the value of the fault detection counter based on the comparison between the filtered residual signal and the dynamic threshold;

[0069] Step 500, compare the counter value with the counter setting value, if the counter value exceeds the setting value, report a fault.

[0070] In step 100, the sensor measurement values ​​of the engine include engine input parameters and gas path parameters. The input parameter I at time t E (t)={T t0 (t), P t0 (t), W f (t), A8(t)}, where T t0 (t) is the total intake air temperature, P t0 (t) is the total intake pressure, W f (t) is the fuel flow rate, A8(t) is the nozzle area. The gas path parameters O at time t E (t)={N L,E (t), N H,E (t),P t25,E (t), P t31,E (t), T t6,E (t)}, where N L,E (t) is the measured value of the low-pressure rotor speed, N H,E (t) is the measured value of the high pressure rotor speed, P t25,E (t) is the measured value of the pressure at the outlet of the low-pressure compressor, P t31,E (t) is the measured value of the pressure at the outlet of the high pressure compressor, T t6,E (t) is the measured value of the temperature at the low-pressure turbine outlet.

[0071] In step 100, the predicted value of the gas path parameter of the engine component level model is based on the engine input parameter I E (t) is calculated, and the predicted value of the gas path parameter at time t is O M (t)={N L,M (t), N H,M (t), P t25,M (t), P t31,M (t),T t6,M (t)}, where N L,M (t) is the predicted value of low-pressure rotor speed calculated by the model, N H,M (t) is the predicted value of high-pressure rotor speed calculated by the model, P t25,M (t) is the predicted value of the pressure at the outlet of the low-pressure compressor calculated by the model, P t31,M (t) is the predicted value of the pressure at the high pressure compressor outlet calculated by the model, Tt6,M (t) is the predicted value of the temperature at the low-pressure turbine outlet calculated by the model.

[0072] In step 200, the prediction residual is calculated by: H , P t25 , P t31 and T t6 The numbers are recorded from 1 to 4 in sequence, and the measurement value of the i-th sensor at time t is recorded as O E,i (t), the predicted value of the i-th sensor at time t is recorded as O M,i (t), calculate the prediction residual of the i-th sensor at time t .

[0073] In step 200, the filtering calculation formula of the residual signal is:

[0074]

[0075] in, is the smoothed residual at time t, and θ is a smoothing factor between 0 and 1.

[0076] In step 300, the low-pressure rotor speed prediction value N is calculated. L,M The root mean square error R(t) corresponding to (t) is calculated iteratively using the formula:

[0077]

[0078] Among them, L R is the calculation window length, R(t-1) is the root mean square error at time t-1, and N L,M (tL R ) is tL R The predicted value of low-pressure rotor speed at time N L,E (tL R ) is tL R The measured value of the low-pressure rotor speed sensor at time.

[0079] In step 300, the root mean square error of the low pressure rotor speed, the dynamic threshold for the i-th sensor fault diagnosis is designed as a function of the root mean square error R(t), which can be expressed as

[0080]

[0081] Among them, δ i (t) is the dynamic threshold for fault diagnosis of the i-th sensor, ε i,k is the proportionality coefficient, ε i,b is the bias coefficient.

[0082] In step 400, the fault detection counter for the i-th sensor can be expressed as

[0083]

[0084] Among them, the value of the counter is a non-negative number, that is, m i (t)≥0.

[0085] In step 400, the method for calculating the value of the fault detection counter is as follows: when the residual The absolute value of is less than the dynamic threshold δ i (t), counter m i (t) decreases, if m i (t)<0, then m i (t) is set to 0. The absolute value of exceeds the dynamic threshold δ i (t), counter m i (t) increase,

[0086] In step 500, the fault detection counter reports a fault in the following manner: Exceeding the dynamic threshold δ for a period of time i (t), that is, satisfying m i (t)>m f,i When , the i-th sensor is reported to be faulty. Among them, the counting boundary m f,i It is a constant and the value can be set according to specific needs.

[0087] In one embodiment, the present disclosure provides a sensor fault dynamic diagnosis method for engine control system fault tolerance, based on sensor P t25 Take the fault as an example:

[0088] Step 100, record engine input parameter I E (t)={T t0 (t), P t0 (t), W f (t), A8(t)}, where T t0 (t) is the total intake air temperature, P t0 (t) is the total intake pressure, W f (t) is the fuel flow rate, A8(t) is the nozzle area. Record the engine sensor measurement value O E (t)={N L,E (t), N H,E (t), P t25,E (t), P t31,E (t), T t6,E (t)}, where N L,E(t) is the measured value of the low-pressure rotor speed, N H,E (t) is the measured value of the high pressure rotor speed, P t25,E (t) is the measured value of the pressure at the outlet of the low-pressure compressor, P t31,E (t) is the measured value of the pressure at the outlet of the high pressure compressor, T t6,E (t) is the measured value of the temperature at the low-pressure turbine outlet.

[0089] Step 200, according to the engine input parameter I E (t), calculate the output O of the component-level model M (t)={N L,M (t), N H,M (t), P t25,M (t), P t31,M (t), T t6,M (t)}, where N L,M (t) is the predicted value of low-pressure rotor speed calculated by the model, N H,M (t) is the predicted value of high-pressure rotor speed calculated by the model, P t25,M (t) is the predicted value of the pressure at the outlet of the low-pressure compressor calculated by the model, P t31,M (t) is the predicted value of the pressure at the high pressure compressor outlet calculated by the model, T t6,M (t) is the predicted value of the temperature at the low-pressure turbine outlet calculated by the model.

[0090] Step 300: Sensor N H , P t25 , P t31 and T t6 The numbers are 1 to 4, then sensor P t25 The measured value is recorded as O E,2 (t), sensor P t25 The predicted value is recorded as O M,2 (t), calculate sensor P t25 The prediction residuals .

[0091] Step 400, sensor P t25 The residual signal r2(t) is filtered, and the filtering calculation formula is:

[0092]

[0093] in, is the sensor P at time t t25 The smoothed residual of , θ is taken as 0.8.

[0094] Step 500, calculating the low pressure rotor speed prediction value N L,M The root mean square error R(t) corresponding to (t) is calculated iteratively using the formula:

[0095]

[0096] Among them, the calculation window length L R Set to 20.

[0097] Step 600, for sensor P t25 The dynamic threshold δ2(t) of fault diagnosis is a function of the root mean square error R(t) of low-pressure speed prediction, and the calculation formula is:

[0098]

[0099] Among them, the proportionality coefficient ε i,k Set to 1.1, bias coefficient ε i,b Set to 0.005.

[0100] Step 700, set sensor P t25 Set the fault detection counter, the counting method is

[0101]

[0102] Among them, the counter value m2(t) is a non-negative number, that is, m2(t)≥0.

[0103] Step 800, calculate sensor P t25 The value of the fault detection counter. When the absolute value of is less than the dynamic threshold δ2(t), the counter m2(t) decreases. If m2(t) < 0, m2(t) is set to 0. When the absolute value of exceeds the dynamic threshold δ2(t), the counter m2(t) increases.

[0104] Step 900, if the smoothed residual If the dynamic threshold δ2(t) is exceeded for a period of time, that is, m2(t)>m f,2 When the sensor P t25 Fault. Among them, the counting boundary m f,2 Set to 20.

[0105] Bias fault is manifested as a large fixed deviation of the sensor measurement value starting from a certain moment, which can be simulated as follows:

[0106]

[0107] Drift fault is manifested as the sensor measurement value deviating at a certain rate from a certain moment, and its simulation method is

[0108]

[0109] Among them, y i (t) represents the signal value when the i-th sensor is fault-free, y i,bf (t) represents the signal value when the i-th sensor has a bias fault, y i,df (t) represents the signal value when the i-th sensor drifts, Δy i Indicates the magnitude of the sensor signal bias amplitude, t f represents the time when the sensor failure occurs, k df Indicates the drift rate of the sensor signal.

[0110] Sensor faults are injected into the engine model to verify the method disclosed in the present invention.

[0111] Figure 2(a) shows the sensor P t25 The fault occurred as an offset fault, the offset size Δy2 = 5000Pa, and the fault occurred at 16.06s.

[0112] Figure 2(b) shows the sensor P t25 The fault occurs drift fault, the drift rate k df = 2500Pa / s, the fault occurred at 16.06s.

[0113] Figure 3(a) shows the sensor P t25 The diagnostic result of the bias fault shows that the sensor fault was diagnosed at 16.54s and the diagnostic time was 0.48s.

[0114] Figure 3(b) shows the sensor P t25 The diagnostic result of the drift fault shows that the sensor fault was diagnosed at 18.24s and the diagnostic time was 2.18s.

[0115] As can be seen from Figure 3(a) and Figure 3(b), the proposed method for dynamic diagnosis of sensor faults for engine control system fault tolerance has good diagnostic effects on both sensor bias faults and drift faults. The method can quickly and accurately diagnose sensor faults without triggering false alarms.

[0116] In one embodiment, the method includes,

[0117] The engine component-level model calculates the predicted value of the sensor according to the input parameters; calculates the predicted residual of each sensor; filters the sensor residual signal; calculates the root mean square error between the predicted value of the engine low-pressure rotor speed and the measured value of the low-pressure speed; uses the low-pressure rotor speed error as a reference to calculate the dynamic threshold corresponding to other sensors except the low-pressure speed; designs a fault indicator, if the residual between the sensor measurement value and the model prediction value is greater than the dynamic threshold, the indicator value increases, otherwise, the indicator value decreases; when the fault indicator value is greater than the set counting boundary, the sensor fault is reported. The present invention can solve the problems of high fault missed detection rate and high false alarm rate in the sensor fault diagnosis method based on fixed thresholds, can timely diagnose the bias and drift faults of the sensor, and has the characteristics of simple algorithm and easy implementation.

[0118] A sensor fault dynamic diagnosis system for engine control system fault tolerance includes:

[0119] A measuring unit detects and records the measured values ​​of the gas path parameter sensor of the engine, and calculates the predicted values ​​of the gas path parameters of the engine component level model based on the engine component level model corresponding to the engine;

[0120] A residual unit, calculating a residual signal between a measured value of each gas path parameter sensor and a corresponding predicted value of the gas path parameter, and filtering the residual signal;

[0121] A threshold calculation unit calculates a root mean square error of the low-pressure rotor speed prediction value, recorded as the low-pressure rotor speed prediction error, and uses the prediction error as a reference to calculate a dynamic threshold corresponding to other gas path sensor fault diagnosis;

[0122] A fault detection counter, which calculates the value of the fault detection counter based on the comparison between the residual signal after filtering and the dynamic threshold;

[0123] The comparison unit compares the counter value with the counter setting value. If the counter value exceeds the setting value, a fault is reported.

[0124] A computer storage medium includes computer instructions, which, when executed on a computer, cause the computer to execute the method described.

[0125] An electronic device, comprising:

[0126] A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein:

[0127] When the processor executes the program, the method described is implemented.

[0128] Although the embodiments of the present invention are described above in conjunction with the accompanying drawings, the present invention is not limited to the above specific embodiments and application fields, and the above specific embodiments are only illustrative and instructive, rather than restrictive. A person of ordinary skill in the art can also make many forms under the guidance of this specification and without departing from the scope of protection of the claims of the present invention, all of which belong to the protection of the present invention.

Claims

1. A sensor fault dynamic diagnosis method for engine control system fault tolerance, characterized in that: The steps include: Step 100, detecting and recording sensor measurement values ​​of the engine, and calculating gas path parameter prediction values ​​of the engine component level model based on the engine component level model corresponding to the engine; Step 200, calculating a residual signal between a measured value of a gas path parameter sensor and a corresponding predicted value of the gas path parameter, and filtering the residual signal; Step 300, calculating the root mean square error of the low-pressure rotor speed prediction value, recorded as the low-pressure rotor speed prediction error, and using the prediction error as a reference, calculating the dynamic threshold corresponding to the fault diagnosis of other gas path sensors; Step 400, setting a sensor fault detection counter, and calculating the value of the fault detection counter based on the comparison between the filtered residual signal and the dynamic threshold; Step 500, compare the counter value with the counter setting value, if the counter value exceeds the setting value, report a fault.

2. The sensor fault dynamic diagnosis method for engine control system fault tolerance according to claim 1, characterized in that: Preferably, the engine includes a low-pressure rotor, a high-pressure rotor, a low-pressure compressor, a high-pressure compressor, a high-pressure turbine and a low-pressure turbine.

3. The sensor fault dynamic diagnosis method for engine control system fault tolerance according to claim 2, characterized in that: The sensor measurement value includes engine input parameters and gas path parameters. The engine input parameter I at time t E (t)={T t0 (t), P t0 (t), W f (t), A8(t)}, where T t0 (t) is the total intake air temperature, P t0 (t) is the total intake pressure, W f (t) is the fuel flow rate, A8(t) is the nozzle area, and the gas path parameter O at time t E (t)={N L,E (t), N H,E (t), P t25,E (t), P t31,E (t), T t6,E (t)}, where N L,E (t) is the measured value of the low-pressure rotor speed, N H,E (t) is the measured value of the high pressure rotor speed, P t25,E (t) is the measured value of the pressure at the outlet of the low-pressure compressor, P t31,E (t) is the measured value of the pressure at the outlet of the high pressure compressor, T t6,E (t) is the measured value of the temperature at the low-pressure turbine outlet.

4. The sensor fault dynamic diagnosis method for engine control system fault tolerance according to claim 3, characterized in that: According to the engine input parameter I E (t) Calculate the predicted value of the gas path parameter at time t O M (t)={N L,M (t), N H,M (t), P t25,M (t), P t31,M (t), T t6,M (t)}, where N L,M (t) is the predicted value of low-pressure rotor speed calculated by the engine component level model, N H,M (t) is the predicted value of the high-pressure rotor speed calculated by the engine component level model, P t25,M (t) is the predicted value of the pressure at the outlet of the low-pressure compressor calculated by the engine component level model, P t31,M (t) is the predicted value of the pressure at the high pressure compressor outlet calculated by the engine component level model, T t6,M (t) is the predicted value of the temperature at the low-pressure turbine outlet calculated by the engine component level model.

5. The sensor fault dynamic diagnosis method for engine control system fault tolerance according to claim 4, characterized in that: In step 200, the prediction residual is calculated by: H , P t25 , P t31 and T t6 The numbers are recorded from 1 to 4 in sequence, and the measurement value of the i-th sensor at time t is recorded as O E,i (t), the predicted value of the i-th sensor at time t is recorded as O M,i (t), calculate the prediction residual of the i-th sensor at time t .

6. The sensor fault dynamic diagnosis method for engine control system fault tolerance according to claim 5, characterized in that: In step 200, the filtering calculation formula of the residual signal is: ， in, is the smoothed residual at time t, and θ is a smoothing factor between 0 and 1.

7. The sensor fault dynamic diagnosis method for engine control system fault tolerance according to claim 6, characterized in that: In step 300, the low-pressure rotor speed prediction value N at time t is calculated. L,M The root mean square error R(t) of (t) is used to calculate the predicted value of low-pressure rotor speed N L,M The dynamic threshold value of the fault diagnosis of the high-pressure rotor speed sensor, the low-pressure compressor outlet pressure sensor, the high-pressure compressor outlet pressure sensor and the low-pressure turbine outlet temperature sensor other than (t) is calculated by the iterative calculation formula of the root mean square error R(t): , where L R is the calculation window length, R(t-1) is the root mean square error at time t-1, and N L,M (tL R ) is tL R The predicted value of low-pressure rotor speed at time N L,E (tL R ) is tL R The measured value of the low-pressure rotor speed sensor at time.

8. A sensor fault dynamic diagnosis system for engine control system fault tolerance, characterized in that: include: A measuring unit, which is used to: detect and record the measured value of the gas path parameter sensor of the engine, and calculate the predicted value of the gas path parameter of the engine component level model based on the engine component level model corresponding to the engine; A residual unit, which is used to: calculate the residual signal between the measured value of each gas path parameter sensor and the corresponding gas path parameter predicted value, and filter the residual signal; A threshold calculation unit, which is used to: calculate the root mean square error of the low-pressure rotor speed prediction value, recorded as the low-pressure rotor speed prediction error, and use the prediction error as a reference to calculate the dynamic threshold corresponding to the fault diagnosis of other gas path sensors; A fault detection counter is used to calculate the value of the fault detection counter based on the comparison between the residual signal after filtering and the dynamic threshold; The comparison unit is used to compare the counter value with the counter setting value, and report a fault if the counter value exceeds the setting value.

9. A computer storage medium, characterized in that The storage medium includes computer instructions, which, when executed on a computer, enable the computer to execute the method according to any one of claims 1 to 7.

10. An electronic device, characterized in that: The electronic device comprises: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the method according to any one of claims 1 to 7 is implemented.

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