An electrical layer fault time determination method employing a multi-value discrimination comparison

Abstract

The application provides an electrical layer fault time determination method adopting multi-value discriminant comparison, and is used for a height measurement system adopting four kinds of measurement devices, namely, inertial components, radio altimeter, diaphragm capsule barometric altimeter and GPS height measurement device, for redundancy fusion measurement; four kinds of signals, namely, inertial height, radio height, diaphragm capsule barometric height and GPS height, are respectively subjected to nonlinear filtering transformation, and then four kinds of filtering speed signals and filtering signals are obtained; the inertial components are independently measured, the interference probability is small, therefore, the relative error data and the absolute error data are obtained by comparing the latter three with the inertial components; the threshold valve is set to judge the time when the fault occurs, and the component causing the fault is further judged according to the mutation of the filtering speed signal; the method has the advantages of accurate judgment and simple implementation.

Description

Technical Field

[0001] This invention relates to the fields of altitude measurement, inertial navigation and fault location, and more specifically, to a method for determining electrical layer fault time using multi-value discrimination comparison. Background Technology

[0002] Altitude information plays a crucial role in the safety and mission execution of aircraft control. Therefore, redundancy-based altitude measurement schemes using multi-sensor data fusion have garnered significant research attention from engineers. Different sensors have their own advantages and limitations, and combined altitude measurement offers reliability advantages that cannot be achieved by a single sensor. However, if a sensor malfunctions, it must be identified and removed to prevent adverse effects on measurement accuracy. Therefore, accurately determining the fault time of a faulty sensor through simple, accurate, and rapid comparison with existing sensor data is a highly valuable research area. Based on this background, this invention proposes a method that uses nonlinear filtering to smooth data, utilizes abrupt changes in the altitude rate data generated by the filter to determine the location of the faulty sensor, and employs relative and absolute errors to determine the fault occurrence time. This method has significant engineering value, is easy to implement, and is more accurate than traditional methods.

[0003] It should be noted that the information in the background section above is only used to enhance the understanding of the background of the present invention, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide a method for determining electrical layer fault time using multi-value discrimination comparison, thereby overcoming the problems of inaccurate fault time judgment and overly complex fault discrimination implementation caused by the limitations and defects of related technologies.

[0005] According to one aspect of the present invention, a method for determining electrical layer fault time using multi-value discrimination comparison is provided, comprising the following steps:

[0006] Step S10: For the altitude redundancy measurement system that uses a combination of inertial altitude measurement, radio altimeter, diaphragm barometric altimeter, and GPS altimeter to measure aircraft altitude using Kalman filtering and redundancy technology, firstly, nonlinear filtering is applied to the inertial altitude data to remove non-smooth data and spike interference data, resulting in an inertial altitude filtered velocity signal; then, integration is performed to obtain the inertial altitude filtered signal; next, nonlinear filtering is applied to the radio altimeter data to remove non-smooth data and spike interference data, resulting in a radio altitude filtered velocity signal, which is then integrated to obtain the radio altitude filtered signal.

[0007] Step S20: For the altitude redundancy measurement system that uses a combination of inertial altitude measurement, radio altimeter, diaphragm barometric altimeter, and GPS altimeter to measure aircraft altitude using Kalman filtering and redundancy techniques, firstly, nonlinear filtering is applied to the diaphragm barometric altimeter to remove non-smooth data and spike interference data, resulting in a diaphragm barometric altimeter filtering velocity signal; then, integration is performed to obtain the diaphragm barometric altimeter filtering signal; next, nonlinear filtering is applied to the GPS altimeter to remove non-smooth data and spike interference data, resulting in a GPS altitude filtering velocity signal, which is then integrated to obtain the GPS altitude filtering signal.

[0008] In step S30, the relative error signal and the absolute error signal of radio altitude are calculated by comparing the inertial altitude filtered signal with the radio altitude filtered signal; the relative error signal and the absolute error signal of diaphragm pressure altitude are calculated by comparing the inertial altitude filtered signal with the diaphragm pressure altitude filtered signal; and the relative error signal and the absolute error signal of GPS altitude are calculated by comparing the inertial altitude filtered signal with the GPS altitude filtered signal.

[0009] In step S40, radio relative fault threshold parameters and radio absolute fault threshold parameters are set, and then the occurrence time of inertial radio fault is determined based on the radio altitude relative error signal and radio altitude absolute error signal; diaphragm pressure relative fault threshold parameters and diaphragm pressure absolute fault threshold parameters are set, and then the occurrence time of inertial diaphragm pressure fault is determined based on the diaphragm pressure altitude relative error signal and diaphragm pressure altitude absolute error signal; GPS relative fault threshold parameters and GPS absolute fault threshold parameters are set, and then the occurrence time of inertial GPS fault is determined based on the GPS altitude relative error signal and GPS altitude absolute error signal.

[0010] In step S50, the inertial altitude filtering speed signal and the radio altitude filtering speed signal are plotted and compared. The presence of abrupt changes in the inertial and radio altitude filtering speed signals at the time of the inertial radio fault determines whether the faulty component is an inertial altimeter or a radio altimeter. Similarly, the inertial altitude filtering speed signal and the diaphragm pressure altimeter filtering speed signal are plotted and compared. The presence of abrupt changes in the inertial and diaphragm pressure altimeter filtering speed signals at the time of the inertial diaphragm pressure fault determines whether the faulty component is an inertial altimeter or a diaphragm pressure altimeter. Finally, the inertial altitude filtering speed signal and the GPS altitude filtering speed signal are plotted and compared. The presence of abrupt changes in the inertial and GPS altitude filtering speed signals at the time of the inertial GPS fault determines whether the faulty component is an inertial altimeter or a GPS altimeter.

[0011] In one exemplary embodiment of the present invention, nonlinear filtering is applied to the inertial altitude data to remove non-smooth and spike interference data, resulting in an inertial altitude filtered velocity signal; then integration is performed to obtain an inertial altitude filtered signal; next, nonlinear filtering is applied to the radio altimeter data to remove non-smooth and spike interference data, resulting in a radio altitude filtered velocity signal, which is then integrated to obtain the following radio altitude filtered signal:

[0012] ;

[0013] ;

[0014] ;

[0015] ;

[0016] ;

[0017] ;

[0018] in For inertial altitude signal, This is a radio altitude signal; This is an inertial highly nonlinear filtering error signal. The velocity signal is filtered by inertial height. This is an inertial height filtered signal; This is a constant time parameter for inertial altitude filtering; , This is the constant gain coefficient for inertial nonlinear filtering; The integral period parameter is a constant value; This is a highly nonlinear filtering error signal for radio waves. This is a radio altitude-filtered speed signal; This is a radio altitude filtered signal; This is a constant time parameter for radio altitude filtering; , This is the constant gain coefficient for radio nonlinear filtering.

[0019] In one exemplary embodiment of the present invention, nonlinear filtering is applied to the diaphragm pressure altitude to remove non-smooth data and spike interference data, resulting in a diaphragm pressure altitude filtered speed signal; then integration is performed to obtain a diaphragm pressure altitude filtered signal; next, nonlinear filtering is applied to the GPS altimeter to remove non-smooth data and spike interference data, resulting in a GPS altitude filtered speed signal, which is then integrated to obtain a GPS altitude filtered signal, including:

[0020] ;

[0021] ;

[0022] ;

[0023] ;

[0024] ;

[0025] ;

[0026] in This is the membrane capsule air pressure height signal. This is a GPS altitude signal; This is the nonlinear filtering error signal for the membrane chamber air pressure. The membrane pressure height is filtered speed signal; The membrane pressure height is filtered signal; This is a constant time parameter for membrane pressure height filtering; , This is the constant gain coefficient for the nonlinear filtering of the membrane air pressure. This is a GPS height nonlinear filtering error signal. The speed signal is filtered by GPS altitude. This is a GPS altitude-filtered signal; This is a constant time parameter for GPS altitude filtering; , This represents the constant gain coefficient for GPS nonlinear filtering.

[0027] In one exemplary embodiment of the present invention, the radio altitude relative error signal and the radio altitude absolute error signal are solved by comparing the inertial altitude filtered signal with the radio altitude filtered signal; the diaphragm pressure altitude relative error signal and the diaphragm pressure altitude absolute error signal are solved by comparing the inertial altitude filtered signal with the diaphragm pressure altitude filtered signal; and the GPS altitude relative error signal and the GPS altitude absolute error signal are solved by comparing the inertial altitude filtered signal with the GPS altitude filtered signal.

[0028] ;

[0029] ;

[0030] ;

[0031] ;

[0032] ;

[0033] ;

[0034] in This is a radio altitude relative error signal. This is the absolute error signal for radio altitude;

[0035] This is the relative error signal of the membrane capsule air pressure height. This is the absolute error signal of the membrane box air pressure height;

[0036] This is the GPS altitude relative error signal. This refers to the GPS altitude absolute error signal.

[0037] In one exemplary embodiment of the present invention, a relative radio fault threshold parameter and an absolute radio fault threshold parameter are set, and then the occurrence time of an inertial radio fault is determined based on the relative radio altitude error signal and the absolute radio altitude error signal; a relative diaphragm pressure fault threshold parameter and an absolute diaphragm pressure fault threshold parameter are set, and then the occurrence time of an inertial diaphragm pressure fault is determined based on the relative diaphragm pressure altitude error signal and the absolute diaphragm pressure altitude error signal; a relative GPS fault threshold parameter and an absolute GPS fault threshold parameter are set, and then the occurrence time of an inertial GPS fault is determined based on the relative GPS altitude error signal and the absolute GPS altitude error signal, including:

[0038] ;

[0039] ,in , ;

[0040] ;

[0041] ,in , ;

[0042] ;

[0043] ,in , ;

[0044] in The time of occurrence of the inertial radio failure; , These are constant parameters, namely the absolute radio fault threshold parameter and the relative radio fault threshold parameter, respectively. This is an inertial radio fault indication signal; An integer representing the starting data sequence number of the inertial radio fault flag transition; The time of occurrence of the inertial diaphragm pressure failure; , These are constant parameters, namely, the absolute fault threshold parameter of the diaphragm pressure and the relative fault threshold parameter of the diaphragm pressure, respectively. This is an inertial diaphragm pressure fault indicator signal; This is an integer, representing the starting data sequence number of the inertial diaphragm pressure fault flag jump; This refers to the time when the inertial GPS malfunction occurred; , These are constant parameters, namely the GPS absolute fault threshold parameter and the GPS relative fault threshold parameter, respectively. This is an inertial GPS fault indication signal; It is an integer, representing the starting data sequence number of the inertial GPS fault flag transition.

[0045] Beneficial effects

[0046] This invention presents a method for determining electrical layer fault time using multi-value discriminant comparison, with the following three main innovations. First, it proposes a nonlinear filtering transformation method to filter data from four measuring devices: inertial components, radio altimeters, diaphragm barometric altimeters, and GPS altimeters. This filters out non-smooth data and spike interference, yielding an inertial height-filtered velocity signal, reducing the probability of misjudgment during fault diagnosis. Second, it leverages the autonomous and independent nature of inertial component measurements and their low probability of interference. Therefore, it compares the data with the radio altimeter, diaphragm barometric altimeter, and GPS altimeter to obtain relative and absolute error data, achieving better accuracy than the traditional method of using only absolute error. Third, it utilizes the image abrupt changes in the height-filtered velocity signal generated during the filtering process to determine whether the altimeter has malfunctioned. This method is not only convenient to implement but also has good identification and high fault identification accuracy.

[0047] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0048] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0049] Figure 1 This is a flowchart of a method for determining electrical layer fault time using multi-value discrimination comparison provided by the present invention;

[0050] Figure 2 This is the inertial altitude filtered signal (unit: meters) provided by the method in the embodiments of the present invention.

[0051] Figure 3 This is the radio altitude filtered signal (unit: meters) provided by the method in the embodiments of the present invention.

[0052] Figure 4 This is the membrane pressure height filtering signal (unit: meters) provided by the method in the embodiments of the present invention.

[0053] Figure 5 This is the GPS altitude filtered signal (unit: meters) provided by the method in the embodiments of the present invention.

[0054] Figure 6 This is the radio altitude absolute error signal (unit: meters) of the method provided in the embodiments of the present invention.

[0055] Figure 7 This is the absolute error signal of membrane box air pressure height (unit: meters) provided in the method of the present invention.

[0056] Figure 8 This is the GPS altitude absolute error signal (unit: meters) provided by the method in the embodiments of the present invention.

[0057] Figure 9 It is the inertial radio fault sign signal (unitless) provided by the method in the embodiments of the present invention;

[0058] Figure 10 This is the inertial diaphragm pressure fault indicator signal (unitless) provided in the embodiments of the present invention.

[0059] Figure 11 It is the inertial GPS fault sign signal (unitless) provided by the method in the embodiments of the present invention;

[0060] Figure 12 It is the inertial height filtered velocity signal (unitless) provided by the method in the embodiments of the present invention;

[0061] Figure 13 It is the radio altitude filtered velocity signal (unitless) provided by the method in the embodiments of the present invention.

[0062] Figure 14 This is the membrane pressure height filtering speed signal (unitless) provided by the method in the embodiments of the present invention.

[0063] Figure 15 It is the GPS altitude filtered speed signal (unitless) provided by the method in the embodiments of the present invention. Detailed Implementation

[0064] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make the invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. The described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a full understanding of embodiments of the invention. However, those skilled in the art will recognize that the technical solutions of the invention may be practiced with one or more of these specific details omitted, or other methods, components, apparatus, steps, etc., may be employed. In other instances, well-known technical solutions are not shown or described in detail to avoid obscuring various aspects of the invention.

[0065] This invention provides a method for determining the time of electrical layer faults using multi-value discrimination comparison. It addresses a height measurement system employing redundancy fusion measurement using four measuring devices: inertial components, radio altimeters, diaphragm barometric altimeters, and GPS altimeters. The method involves nonlinearly filtering and transforming the inertial, radio, diaphragm barometric altimeter, and GPS altitude signals respectively, resulting in four filtered velocity signals and filtered signals. Considering the autonomous and independent nature of inertial measurements and their low probability of interference, the latter three are compared with the inertial components to obtain relative and absolute error data. A threshold is set to determine the time of fault occurrence, and the abrupt changes in the filtered velocity signal are used to further identify the faulty component. This method offers the advantages of accurate judgment and simple implementation.

[0066] The following will, with reference to the accompanying drawings, further explain and illustrate the present invention's method for determining electrical layer fault time using multi-value discrimination comparison. (Reference) Figure 1 As shown, this method for determining electrical layer fault time using multi-value discrimination comparison may include the following steps:

[0067] Step S10: For the altitude redundancy measurement system that uses a combination of inertial altitude measurement, radio altimeter, diaphragm barometric altimeter, and GPS altimeter to measure aircraft altitude using Kalman filtering and redundancy technology, firstly, nonlinear filtering is applied to the inertial altitude data to remove non-smooth data and spike interference data, resulting in an inertial altitude filtered velocity signal; then, integration is performed to obtain the inertial altitude filtered signal; next, nonlinear filtering is applied to the radio altimeter data to remove non-smooth data and spike interference data, resulting in a radio altitude filtered velocity signal, which is then integrated to obtain the radio altitude filtered signal.

[0068] Specifically, this can be broken down into the following four steps. The first step is to calculate the difference between the inertial altitude signal and the filtered inertial altitude signal to obtain the inertial altitude filtering error signal, as follows:

[0069] ;

[0070] in This is an inertial altitude signal; This is an inertial, highly nonlinear filtering error signal.

[0071] The second step involves performing a nonlinear transformation on the inertial altitude filtering error signal to solve for the inertial altitude filtered velocity signal, followed by integration to obtain the inertial altitude filtered signal as follows:

[0072] ;

[0073] ;

[0074] in The velocity signal is filtered by inertial height. This is an inertial height filtered signal; This is a constant time parameter for inertial altitude filtering; , This is the constant gain coefficient for inertial nonlinear filtering; The integral period parameter is a constant.

[0075] The third step involves calculating the difference between the radio altitude and the filtered radio altitude signal to obtain the radio altitude filtering error signal, as follows:

[0076] ;

[0077] in For radio altitude signals, This is a highly nonlinear filtering error signal for radio waves.

[0078] The fourth step involves performing a nonlinear transformation on the radio altitude filtering error signal to solve for the radio altitude filtering velocity signal, followed by integration to obtain the radio altitude filtering signal as follows:

[0079] ;

[0080] ;

[0081] in This is a radio altitude-filtered speed signal; This is a radio altitude filtered signal; This is a constant time parameter for radio altitude filtering; , This is the constant gain coefficient for radio nonlinear filtering.

[0082] Step S20: For the altitude redundancy measurement system that uses a combination of inertial altitude measurement, radio altimeter, diaphragm barometric altimeter, and GPS altimeter to measure aircraft altitude using Kalman filtering and redundancy techniques, firstly, nonlinear filtering is applied to the diaphragm barometric altimeter to remove non-smooth data and spike interference data, resulting in a diaphragm barometric altimeter filtering velocity signal; then, integration is performed to obtain the diaphragm barometric altimeter filtering signal; next, nonlinear filtering is applied to the GPS altimeter to remove non-smooth data and spike interference data, resulting in a GPS altitude filtering velocity signal, which is then integrated to obtain the GPS altitude filtering signal.

[0083] Specifically, it can be broken down into the following four steps. The first step is to calculate the difference between the membrane pressure height and the filtered membrane pressure height signal to obtain the membrane pressure height filtering error signal, as follows:

[0084] ;

[0085] in This is the membrane capsule air pressure height signal. This is the nonlinear filtering error signal for the membrane air pressure height.

[0086] The second step involves performing a nonlinear transformation on the membrane pressure height filtering error signal to solve for the membrane pressure height filtering velocity signal, followed by integration to obtain the membrane pressure height filtering signal as follows:

[0087] ;

[0088] ;

[0089] in The membrane pressure height is filtered speed signal; The membrane pressure height is filtered signal; This is a constant time parameter for membrane pressure height filtering; , This is the constant gain coefficient for the nonlinear filter of the membrane air pressure.

[0090] The third step involves calculating the difference between the GPS altitude and the filtered GPS altitude signal to obtain the GPS altitude filtering error signal, as follows:

[0091] ;

[0092] in This is a GPS altitude signal; This is the GPS height nonlinear filtering error signal.

[0093] The fourth step involves performing a nonlinear transformation on the GPS altitude filtering error signal to solve for the GPS altitude filtering velocity signal, followed by integration to obtain the GPS altitude filtering signal as follows:

[0094] ;

[0095] ;

[0096] in The speed signal is filtered by GPS altitude. This is a GPS altitude-filtered signal; This is a constant time parameter for GPS altitude filtering; , This represents the constant gain coefficient for GPS nonlinear filtering.

[0097] In step S30, the relative error signal and the absolute error signal of radio altitude are calculated by comparing the inertial altitude filtered signal with the radio altitude filtered signal; the relative error signal and the absolute error signal of diaphragm pressure altitude are calculated by comparing the inertial altitude filtered signal with the diaphragm pressure altitude filtered signal; and the relative error signal and the absolute error signal of GPS altitude are calculated by comparing the inertial altitude filtered signal with the GPS altitude filtered signal.

[0098] Specifically, this can be broken down into the following three steps. The first step is to compare the inertial altitude filter signal and the radio altitude filter signal to determine the relative and absolute radio altitude errors as follows:

[0099] ;

[0100] ;

[0101] in This is a radio altitude relative error signal. This is the absolute error signal for radio altitude.

[0102] The second step involves comparing the inertial height filter signal with the diaphragm pressure height filter signal to determine the relative error signal and absolute error signal of the diaphragm pressure height, as follows:

[0103] ;

[0104] ;

[0105] in This is the relative error signal of the membrane capsule air pressure height. This is the absolute error signal for the membrane box air pressure height.

[0106] The third step involves comparing the inertial altitude filter signal with the GPS altitude filter signal to determine the GPS altitude relative error signal and the GPS altitude absolute error signal as follows:

[0107] ;

[0108] ;

[0109] in This is the GPS altitude relative error signal. This refers to the GPS altitude absolute error signal.

[0110] In step S40, radio relative fault threshold parameters and radio absolute fault threshold parameters are set, and then the occurrence time of inertial radio fault is determined based on the radio altitude relative error signal and radio altitude absolute error signal; diaphragm pressure relative fault threshold parameters and diaphragm pressure absolute fault threshold parameters are set, and then the occurrence time of inertial diaphragm pressure fault is determined based on the diaphragm pressure altitude relative error signal and diaphragm pressure altitude absolute error signal; GPS relative fault threshold parameters and GPS absolute fault threshold parameters are set, and then the occurrence time of inertial GPS fault is determined based on the GPS altitude relative error signal and GPS altitude absolute error signal.

[0111] Specifically, this can be broken down into the following three steps. First, set the relative radio fault threshold parameter and the absolute radio fault threshold parameter. Then, based on the relative radio altitude error signal and the absolute radio altitude error signal, determine the occurrence time of the inertial radio fault as follows:

[0112] ;

[0113] ,in , ;

[0114] in The time of occurrence of the inertial radio failure; , These are constant parameters, namely the absolute radio fault threshold parameter and the relative radio fault threshold parameter, respectively. This is an inertial radio fault indication signal; , an integer, is the starting data sequence number of the inertial radio fault flag transition.

[0115] The second step involves setting the relative fault threshold parameter and the absolute fault threshold parameter for diaphragm pressure. Then, based on the relative error signal and the absolute error signal of diaphragm pressure height, the occurrence time of the inertial diaphragm pressure fault is determined as follows:

[0116] ;

[0117] ,in , ;

[0118] in The time of occurrence of the inertial diaphragm pressure failure; , These are constant parameters, namely, the absolute fault threshold parameter of the diaphragm pressure and the relative fault threshold parameter of the diaphragm pressure, respectively. This is an inertial diaphragm pressure fault indicator signal; It is an integer, representing the starting data sequence number of the inertial diaphragm pressure fault flag jump.

[0119] The third step is to set the GPS relative fault threshold parameters and the GPS absolute fault threshold parameters, and then determine the inertial GPS fault occurrence time based on the GPS relative altitude error signal and the GPS absolute altitude error signal as follows:

[0120] ;

[0121] ,in , ;

[0122] in This refers to the time when the inertial GPS malfunction occurred; , These are constant parameters, namely the GPS absolute fault threshold parameter and the GPS relative fault threshold parameter, respectively. This is an inertial GPS fault indication signal; It is an integer, representing the starting data sequence number of the inertial GPS fault flag transition.

[0123] In step S50, the inertial altitude filtering speed signal and the radio altitude filtering speed signal are plotted and compared. The presence of abrupt changes in the inertial and radio altitude filtering speed signals at the time of the inertial radio fault determines whether the faulty component is an inertial altimeter or a radio altimeter. Similarly, the inertial altitude filtering speed signal and the diaphragm pressure altimeter filtering speed signal are plotted and compared. The presence of abrupt changes in the inertial and diaphragm pressure altimeter filtering speed signals at the time of the inertial diaphragm pressure fault determines whether the faulty component is an inertial altimeter or a diaphragm pressure altimeter. Finally, the inertial altitude filtering speed signal and the GPS altitude filtering speed signal are plotted and compared. The presence of abrupt changes in the inertial and GPS altitude filtering speed signals at the time of the inertial GPS fault determines whether the faulty component is an inertial altimeter or a GPS altimeter.

[0124] Case Implementation and Computer Simulation Results Analysis

[0125] In step S10, select , , The inertial height filtered signal is obtained as follows Figure 2 As shown; the obtained radio altitude filtered signal is as follows Figure 3 As shown.

[0126] In step S20, select , The membrane pressure height filtered signal is obtained as follows: Figure 4 As shown, the GPS altitude filtered signal is obtained as follows: Figure 5 As shown.

[0127] In step S30, the absolute error signal of radio altitude is obtained as follows: Figure 6 As shown; the absolute error signal of the membrane box air pressure height is obtained as follows. Figure 7 As shown; the GPS altitude absolute error signal is obtained as follows. Figure 8 As shown.

[0128] In step S40, select , , , , , The inertial radio fault sign signal is obtained as follows: Figure 9 As shown; the inertial diaphragm pressure fault indicator signal is as follows: Figure 10 As shown; inertial GPS fault sign signal such as Figure 11 As shown.

[0129] In step S50, the inertial height filtered velocity signal is obtained as follows: Figure 12 As shown, the radio altitude filtered speed signal is as follows: Figure 13 As shown, the membrane chamber air pressure height filtering speed signal is as follows: Figure 14 As shown, the GPS altitude-filtered speed signal is as follows: Figure 15 As shown.

[0130] Depend on Figure 9 , 10 As can be clearly seen from points 1 and 11, the failure times are 7s, 5.8s, and 8s respectively. Figure 13 , 14 As can be seen from 15, at the fault time, the filtered velocity signal undergoes a significant jump, or the slope changes significantly before and after the jump. Figure 13 As can be seen, the sensor actually malfunctioned within 5 seconds, but the error did not exceed the threshold at this time. Therefore, it was not until 5.8 seconds that the error was detected as exceeding the threshold, and a fault flag was triggered. The above experimental results show that the method provided by this invention can simply and clearly determine the fault time and the faulty component, thus having great practical engineering value.

Claims

1. A method for determining electrical layer fault time using multi-valued discrimination comparison, characterized by the following steps: Step S10: For the altitude redundancy measurement system that combines inertial altitude measurement, radio altimeter, diaphragm barometric altimeter, and GPS altimeter with Kalman filtering and redundancy techniques to measure aircraft altitude, firstly, nonlinear filtering is applied to the inertial altitude data to remove non-smooth and spike interference data, resulting in an inertial altitude filtered velocity signal; then, integration is performed to obtain the inertial altitude filtered signal; next, nonlinear filtering is applied to the radio altimeter data to remove non-smooth and spike interference data, resulting in a radio altitude filtered velocity signal, which is then integrated to obtain the following radio altitude filtered signal: ； ； ； ； ； ； in For inertial altitude signal, This is a radio altitude signal; This is an inertial highly nonlinear filtering error signal. The velocity signal is filtered by inertial height. This is an inertial height filtered signal; This is a constant time parameter for inertial altitude filtering; , This is the constant gain coefficient for inertial nonlinear filtering; The integral period parameter is a constant value; This is a highly nonlinear filtering error signal for radio waves. This is a radio altitude-filtered speed signal; This is a radio altitude filtered signal; This is a constant time parameter for radio altitude filtering; , This is the constant gain coefficient for radio nonlinear filtering; Step S20: For the altitude redundancy measurement system that combines inertial altitude measurement, radio altimeter, diaphragm barometric altimeter, and GPS altimeter with Kalman filtering and redundancy techniques to measure aircraft altitude, firstly, nonlinear filtering is applied to the diaphragm barometric altimeter to remove non-smooth and spike interference data, resulting in a diaphragm barometric altimeter filter velocity signal; then, integration is performed to obtain the diaphragm barometric altimeter filter signal; next, nonlinear filtering is applied to the GPS altimeter to remove non-smooth and spike interference data, resulting in a GPS altitude filter velocity signal, which is then integrated to obtain the following GPS altitude filter signal: ； ； ； ； ； ； in This is the membrane capsule air pressure height signal. This is a GPS altitude signal; This is the nonlinear filtering error signal for the membrane chamber air pressure. The membrane pressure height is filtered speed signal; The membrane pressure height is filtered signal; This is a constant time parameter for membrane pressure height filtering; , This is the constant gain coefficient for the nonlinear filtering of the membrane air pressure. This is a GPS height nonlinear filtering error signal. The speed signal is filtered by GPS altitude. This is a GPS altitude-filtered signal; This is a constant time parameter for GPS altitude filtering; , This is the constant gain coefficient for GPS nonlinear filtering; In step S30, the relative and absolute errors of radio altitude are calculated by comparing the inertial altitude filter signal with the radio altitude filter signal; the relative and absolute errors of diaphragm pressure altitude are calculated by comparing the inertial altitude filter signal with the diaphragm pressure altitude filter signal; and the relative and absolute errors of GPS altitude are calculated by comparing the inertial altitude filter signal with the GPS altitude filter signal, as follows: ； ； ； ； ； ； in This is a radio altitude relative error signal. This is the absolute error signal for radio altitude; This is the relative error signal of the membrane capsule air pressure height. This is the absolute error signal of the membrane box air pressure height; This is the GPS altitude relative error signal. This is the GPS altitude absolute error signal; In step S40, radio relative fault threshold parameters and radio absolute fault threshold parameters are set, and then the occurrence time of inertial radio faults is determined based on the radio altitude relative error signal and radio altitude absolute error signal; diaphragm pressure relative fault threshold parameters and diaphragm pressure absolute fault threshold parameters are set, and then the occurrence time of inertial diaphragm pressure faults is determined based on the diaphragm pressure altitude relative error signal and diaphragm pressure altitude absolute error signal; GPS relative fault threshold parameters and GPS absolute fault threshold parameters are set, and then the occurrence time of inertial GPS faults is determined based on the GPS altitude relative error signal and GPS altitude absolute error signal as follows: ； ,in , ; ； ,in , ; ； ,in , ; in The time of occurrence of the inertial radio failure; , These are constant parameters, namely the absolute radio fault threshold parameter and the relative radio fault threshold parameter, respectively. This is an inertial radio fault indication signal; An integer representing the starting data sequence number of the inertial radio fault flag transition; The time of occurrence of the inertial diaphragm pressure failure; , These are constant parameters, namely, the absolute fault threshold parameter of the diaphragm pressure and the relative fault threshold parameter of the diaphragm pressure, respectively. This is an inertial diaphragm pressure fault indicator signal; This is an integer, representing the starting data sequence number of the inertial diaphragm pressure fault flag jump; This refers to the time when the inertial GPS malfunction occurred; , These are constant parameters, namely the GPS absolute fault threshold parameter and the GPS relative fault threshold parameter, respectively. This is an inertial GPS fault indication signal; An integer representing the starting data sequence number of the inertial GPS fault flag transition; In step S50, the inertial altitude filtering speed signal and the radio altitude filtering speed signal are plotted and compared. The presence of abrupt changes in the inertial and radio altitude filtering speed signals at the time of the inertial radio fault determines whether the faulty component is an inertial altimeter or a radio altimeter. Similarly, the inertial altitude filtering speed signal and the diaphragm pressure altimeter filtering speed signal are plotted and compared. The presence of abrupt changes in the inertial and diaphragm pressure altimeter filtering speed signals at the time of the inertial diaphragm pressure fault determines whether the faulty component is an inertial altimeter or a diaphragm pressure altimeter. Finally, the inertial altitude filtering speed signal and the GPS altitude filtering speed signal are plotted and compared. The presence of abrupt changes in the inertial and GPS altitude filtering speed signals at the time of the inertial GPS fault determines whether the faulty component is an inertial altimeter or a GPS altimeter.

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